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From: skunkwerk <sku...@gm...> - 2008-04-28 00:09:17
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bool MainWindow::textureAtlas()
{
//this function takes every texture in the model and creates a single texture composed of all the individual textures - necessary before calling the Quadric-with-texture filter
//QT has support for all the major image formats (GIF/JPEG/PNG/BMP/TIFF) - though you need to compile QT with -qt-gif to get GIF support (on Ubuntu the package for qt already has this - check your /usr/share/qt4/plugins/imageformats folder
//can't do any collada-specific calls, this has to be generalizable to any model
//TODO:how read image data from images already loaded into Meshlab, to prevent from opening files again?
//TODO:improve atlas-generation algorithm so it tries to minimize whitespace (though saved PNG files don't increase in file size due to whitespace)
int totalWidth=0, totalHeight=0;
int numTextures = GLA()->mm()->cm.textures.size();
if ((numTextures == 0)||(numTextures == 1))
return false;//return false if numTextures == 0 or 1 (no need for an atlas)
QPixmap images[numTextures];//array of images
for (unsigned textureIdx = 0; textureIdx < numTextures; ++textureIdx)//iterate through textures, loading each
{
images[textureIdx] = QPixmap(GLA()->mm()->cm.textures[textureIdx].c_str());//loads image, if fails is a null image. will guess extension from file name
totalWidth += images[textureIdx].width();//get total x dimensions
totalHeight += images[textureIdx].height();//get total y dimensions
}
std::map<int, int> Xoffset;//stl map mapping texture indeces to new U offsets
std::map<int, int> Yoffset;//stl map mapping texture indeces to new V offsets
//query with conversions[integer variable] (will return null array if no match?), or .find
//set with conversions.insert
int dimension;
totalWidth > totalHeight ? dimension = totalWidth : dimension = totalHeight;//if/else shortcut: if totalWidth is greater than totalHeight, assign dimension to totalWidth, otherwise totalHeight
QImage atlas = QImage(dimension, dimension, QImage::Format_ARGB32);//make a square texture of that dimension
//insert textures one after another in one row, starting at 0,0
QPainter painter(&atlas);
int currentX=0; //currentY=0;
for (int index=0; index<numTextures; ++index)
{
painter.drawPixmap(currentX, 0, images[index]);//use drawPixmap instead of deprecated bitBlt() to paste image to a certain position in the texture atlas
currentX += images[index].width();
Xoffset[index] = currentX;//as do, add index & coords to 'conversions' map
}
int tmpX=0,tmpY=0;
for(vcg::tri::io::ConstFaceIterator fit=GLA()->mm()->cm.face.begin(); fit != GLA()->mm()->cm.face.end(); ++fit)//iterate through faces with textures (don't have to check if face is deleted as this should be run before the filter)
{
int mat = fit->cWT(0).N();
if (mat!=-1)
fit->cWT(0).N() = 0; //re-assign N to 0 (only one tex now)
tmpX = Xoffset[mat];//retrieve offsets (currently only x)
for(unsigned int ii = 0; ii < 3;++ii)//UVs are per-vertex?
{
fit->cWT(ii).U() = (fit->cWT(ii).U()*images[mat].width() + tmpX)/dimension;//offset U by coord in map array, then normalize (between 0 & 1)
fit->cWT(ii).V() = (fit->cWT(ii).V()*images[mat].height() + tmpY)/dimension;//offset V by coord in map array, then normalize (between 0 & 1)
}
}
bool result = atlas.save("texture.png","PNG",0);//save image, highest compression
GLA()->mm()->cm.textures.clear();//empty mm.cm.textures vector
GLA()->mm()->cm.textures.push_back("texture.png");//add the texture atlas (at position 0)
//update display-load texture atlas?
return result;
} |
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From: Paolo C. <pao...@is...> - 2008-04-29 09:15:48
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skunkwerk wrote: > i've attached a texture atlas function. > > it compiles except for a ConstFaceIterator error - I've tried using > the template<typename MESHTYPE> but that didn't work either. the > algorithm is VERY basic (textures are added one after another in a > row), but should work. i couldn't find any algorithms for more > closely-packed positioning, but i could look at the code in > openscenegraph's texture atlas generator. Nice Job! The right place for this stuff is the filter_texture plugin that i have just added, Now it is just a placeholder filter you should add your code there. Important: In the plugin dir you can find a rect_packer that should make good job. please use it to build a good packing of the texture size > questions: > 1) if someone could tell me how to iterate through faces from a > function outside vcg, that'd be great so i could test this out We have started to improve the developer documentation: two new pages in the wiki should help you http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh http://meshlab.sourceforge.net/wiki/index.php/Algorithms > 2) paolo, what's the best location of this function? i'm currently > putting it in mainwindow_Runtime.cpp to test it out The right location is inside the filter_texture plugin possible parameter of the plugin: - format of the saved texture (as a enum) - max size of the texture > 3) how do I access the data from already-loaded textures? so i can > prevent having to load all the textures again... Do not worry about that. Feel free to use QT to load again the images and process them, it should not create a significant overhead. Once your processing is ended (and you have saved the new texture) you should update the texture names stored inside the mesh sending a signal to the updateTexture() slot of the mainwindow (the parent of the action) cheers p. -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-04-29 17:45:37
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thanks for the hints paolo, i wanted to use this algorithm: http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm but it seemed like it needed information on the actual models, and was taking in arbitrarily-shaped textures. the only other algorithm i've found for texture packing is a recursive tree-based one: http://www.blackpawn.com/texts/lightmaps/default.html i tried this line (along with everything else i could think of): MeshModel::FaceIterator fit; but it didn't like the 'MeshModel' part - is 'mm' not an object of type MeshModel? if someone could suggest the correct syntax i can get started on testing the texture atlas thanks, imran On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni <pao...@is...> wrote: > skunkwerk wrote: > > i've attached a texture atlas function. > > > > it compiles except for a ConstFaceIterator error - I've tried using > > the template<typename MESHTYPE> but that didn't work either. the > > algorithm is VERY basic (textures are added one after another in a > > row), but should work. i couldn't find any algorithms for more > > closely-packed positioning, but i could look at the code in > > openscenegraph's texture atlas generator. > Nice Job! > > The right place for this stuff is the filter_texture plugin that i have > just added, > Now it is just a placeholder filter you should add your code there. > > Important: > In the plugin dir you can find a rect_packer that should make good job. > please use it to build a good packing of the texture size > > > questions: > > 1) if someone could tell me how to iterate through faces from a > > function outside vcg, that'd be great so i could test this out > We have started to improve the developer documentation: two new pages in > the wiki should help you > > http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh > http://meshlab.sourceforge.net/wiki/index.php/Algorithms > > > 2) paolo, what's the best location of this function? i'm currently > > putting it in mainwindow_Runtime.cpp to test it out > The right location is inside the filter_texture plugin > possible parameter of the plugin: > - format of the saved texture (as a enum) > - max size of the texture > > > 3) how do I access the data from already-loaded textures? so i can > > prevent having to load all the textures again... > Do not worry about that. Feel free to use QT to load again the images > and process them, it should not create a significant overhead. > > Once your processing is ended (and you have saved the new texture) you > should update the texture names stored inside the mesh sending a signal > to the updateTexture() slot of the mainwindow (the parent of the action) > > cheers > p. > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > |
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From: Paolo C. <pao...@is...> - 2008-04-29 21:23:11
|
I like your proposal, but I strongly suggest you to proceed gradually and start and complete and test a functionality at a time. First of all start to just add a simple rectangular packer, - then try to use the rect_packer provided code - then try to look at the code in the trimesh/textcoord_optimization.h file. Before facing LSCM we should solve the issue of what numerical solver use for it and for other issues that we have around in the vcg. I hope we could take some decision in the next weeks about the numeric solver in the vcg. I noticed that some notes on the basic types were missing so i added it in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin Feel also free to contribute to the wiki in the part about the writing of the plugins when you see points needing some clarification or a deeper discussion. cheers p. skunkwerk wrote: > thanks for the hints paolo, > i wanted to use this algorithm: > http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm > but it seemed like it needed information on the actual models, and was > taking in arbitrarily-shaped textures. > > the only other algorithm i've found for texture packing is a recursive > tree-based one: > http://www.blackpawn.com/texts/lightmaps/default.html > > i tried this line (along with everything else i could think of): > MeshModel::FaceIterator fit; > but it didn't like the 'MeshModel' part - is 'mm' not an object of > type MeshModel? > > if someone could suggest the correct syntax i can get started on > testing the texture atlas > > thanks, > imran > > On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > skunkwerk wrote: > > i've attached a texture atlas function. > > > > it compiles except for a ConstFaceIterator error - I've tried using > > the template<typename MESHTYPE> but that didn't work either. the > > algorithm is VERY basic (textures are added one after another in a > > row), but should work. i couldn't find any algorithms for more > > closely-packed positioning, but i could look at the code in > > openscenegraph's texture atlas generator. > Nice Job! > > The right place for this stuff is the filter_texture plugin that i > have > just added, > Now it is just a placeholder filter you should add your code there. > > Important: > In the plugin dir you can find a rect_packer that should make good > job. > please use it to build a good packing of the texture size > > > questions: > > 1) if someone could tell me how to iterate through faces from a > > function outside vcg, that'd be great so i could test this out > We have started to improve the developer documentation: two new > pages in > the wiki should help you > > http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh > http://meshlab.sourceforge.net/wiki/index.php/Algorithms > > > 2) paolo, what's the best location of this function? i'm currently > > putting it in mainwindow_Runtime.cpp to test it out > The right location is inside the filter_texture plugin > possible parameter of the plugin: > - format of the saved texture (as a enum) > - max size of the texture > > > 3) how do I access the data from already-loaded textures? so i can > > prevent having to load all the textures again... > Do not worry about that. Feel free to use QT to load again the images > and process them, it should not create a significant overhead. > > Once your processing is ended (and you have saved the new texture) > you > should update the texture names stored inside the mesh sending a > signal > to the updateTexture() slot of the mainwindow (the parent of the > action) > > cheers > p. > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save > $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-04-30 06:49:04
|
thanks Paolo, i guess CMesh0 is how i'll get the faceiterator - i'm working on some collada importer optimizations right now but might get back to this in a few days. what options do we have for a numerical solver? imran On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni <pao...@is...> wrote: > I like your proposal, but I strongly suggest you to proceed gradually and > start and complete and test a functionality at a time. > > First of all start to just add a simple rectangular packer, > > - then try to use the rect_packer provided code > > - then try to look at the code in the trimesh/textcoord_optimization.h > file. > > Before facing LSCM we should solve the issue of what numerical solver use > for it and for other issues that we have around in the vcg. > I hope we could take some decision in the next weeks about the numeric > solver in the vcg. > > I noticed that some notes on the basic types were missing so i added it in > http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin > Feel also free to contribute to the wiki in the part about the writing of > the plugins when you see points needing some clarification or a deeper > discussion. > > > cheers > p. > > > > > > > > skunkwerk wrote: > > thanks for the hints paolo, > i wanted to use this algorithm: > http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm > but it seemed like it needed information on the actual models, and was > taking in arbitrarily-shaped textures. > > the only other algorithm i've found for texture packing is a recursive > tree-based one: > http://www.blackpawn.com/texts/lightmaps/default.html > > i tried this line (along with everything else i could think of): > MeshModel::FaceIterator fit; > but it didn't like the 'MeshModel' part - is 'mm' not an object of type > MeshModel? > > if someone could suggest the correct syntax i can get started on testing > the texture atlas > > thanks, > imran > > On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni <pao...@is...> > wrote: > > skunkwerk wrote: > > i've attached a texture atlas function. > > > > it compiles except for a ConstFaceIterator error - I've tried using > > the template<typename MESHTYPE> but that didn't work either. the > > algorithm is VERY basic (textures are added one after another in a > > row), but should work. i couldn't find any algorithms for more > > closely-packed positioning, but i could look at the code in > > openscenegraph's texture atlas generator. > Nice Job! > > The right place for this stuff is the filter_texture plugin that i have > just added, > Now it is just a placeholder filter you should add your code there. > > Important: > In the plugin dir you can find a rect_packer that should make good job. > please use it to build a good packing of the texture size > > > questions: > > 1) if someone could tell me how to iterate through faces from a > > function outside vcg, that'd be great so i could test this out > We have started to improve the developer documentation: two new pages in > the wiki should help you > > http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh > http://meshlab.sourceforge.net/wiki/index.php/Algorithms > > > 2) paolo, what's the best location of this function? i'm currently > > putting it in mainwindow_Runtime.cpp to test it out > The right location is inside the filter_texture plugin > possible parameter of the plugin: > - format of the saved texture (as a enum) > - max size of the texture > > > 3) how do I access the data from already-loaded textures? so i can > > prevent having to load all the textures again... > Do not worry about that. Feel free to use QT to load again the images > and process them, it should not create a significant overhead. > > Once your processing is ended (and you have saved the new texture) you > should update the texture names stored inside the mesh sending a signal > to the updateTexture() slot of the mainwindow (the parent of the action) > > cheers > p. > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
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From: skunkwerk <sku...@gm...> - 2008-05-07 15:48:17
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i'm using a CMesh0::FaceIterator but it seems like it's a const for some reason - when I try to change values of the face, like fit->cWT(0).N() i get compilation errors about 'assignment of read-only location.' what's the proper way to modify these values? i was translating some of the italian comments in rect_packer.cpp but couldn't find translations for the following: posiziono - position? pe plus' could someone please translate these to english for me? thanks imran On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> wrote: > thanks Paolo, > i guess CMesh0 is how i'll get the faceiterator - i'm working on some > collada importer optimizations right now but might get back to this in a few > days. what options do we have for a numerical solver? > > imran > > > On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni <pao...@is...> > wrote: > > > I like your proposal, but I strongly suggest you to proceed gradually > > and start and complete and test a functionality at a time. > > > > First of all start to just add a simple rectangular packer, > > > > - then try to use the rect_packer provided code > > > > - then try to look at the code in the trimesh/textcoord_optimization.h > > file. > > > > Before facing LSCM we should solve the issue of what numerical solver > > use for it and for other issues that we have around in the vcg. > > I hope we could take some decision in the next weeks about the numeric > > solver in the vcg. > > > > I noticed that some notes on the basic types were missing so i added it > > in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin > > Feel also free to contribute to the wiki in the part about the writing > > of the plugins when you see points needing some clarification or a deeper > > discussion. > > > > > > cheers > > p. > > > > > > > > > > > > > > > > skunkwerk wrote: > > > > thanks for the hints paolo, > > i wanted to use this algorithm: > > http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm > > but it seemed like it needed information on the actual models, and was > > taking in arbitrarily-shaped textures. > > > > the only other algorithm i've found for texture packing is a recursive > > tree-based one: > > http://www.blackpawn.com/texts/lightmaps/default.html > > > > i tried this line (along with everything else i could think of): > > MeshModel::FaceIterator fit; > > but it didn't like the 'MeshModel' part - is 'mm' not an object of type > > MeshModel? > > > > if someone could suggest the correct syntax i can get started on testing > > the texture atlas > > > > thanks, > > imran > > > > On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < > > pao...@is...> wrote: > > > > skunkwerk wrote: > > > i've attached a texture atlas function. > > > > > > it compiles except for a ConstFaceIterator error - I've tried using > > > the template<typename MESHTYPE> but that didn't work either. the > > > algorithm is VERY basic (textures are added one after another in a > > > row), but should work. i couldn't find any algorithms for more > > > closely-packed positioning, but i could look at the code in > > > openscenegraph's texture atlas generator. > > Nice Job! > > > > The right place for this stuff is the filter_texture plugin that i have > > just added, > > Now it is just a placeholder filter you should add your code there. > > > > Important: > > In the plugin dir you can find a rect_packer that should make good job. > > please use it to build a good packing of the texture size > > > > > questions: > > > 1) if someone could tell me how to iterate through faces from a > > > function outside vcg, that'd be great so i could test this out > > We have started to improve the developer documentation: two new pages > > in > > the wiki should help you > > > > http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh > > http://meshlab.sourceforge.net/wiki/index.php/Algorithms > > > > > 2) paolo, what's the best location of this function? i'm currently > > > putting it in mainwindow_Runtime.cpp to test it out > > The right location is inside the filter_texture plugin > > possible parameter of the plugin: > > - format of the saved texture (as a enum) > > - max size of the texture > > > > > 3) how do I access the data from already-loaded textures? so i can > > > prevent having to load all the textures again... > > Do not worry about that. Feel free to use QT to load again the images > > and process them, it should not create a significant overhead. > > > > Once your processing is ended (and you have saved the new texture) you > > should update the texture names stored inside the mesh sending a signal > > to the updateTexture() slot of the mainwindow (the parent of the > > action) > > > > cheers > > p. > > > > -- > > Paolo Cignoni -- Senior Researcher > > Visual Computing Laboratory - ISTI - CNR > > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > > > ISTI - CNR > > Via Moruzzi 1, > > 56124 Pisa > > ITALY > > > > > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > Don't miss this year's exciting event. There's still time to save $100. > > Use priority code J8TL2D2. > > > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > _______________________________________________ > > Meshlab-devel mailing list > > Mes...@li... > > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > > ------------------------------ > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > Don't miss this year's exciting event. There's still time to save $100. > > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > > > ------------------------------ > > > > _______________________________________________ > > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > > > > -- > > Paolo Cignoni -- Senior Researcher > > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > > > ISTI - CNR > > Via Moruzzi 1, > > 56124 Pisa > > ITALY > > > > > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > Don't miss this year's exciting event. There's still time to save $100. > > Use priority code J8TL2D2. > > > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > _______________________________________________ > > Meshlab-devel mailing list > > Mes...@li... > > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > |
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From: Paolo C. <pao...@is...> - 2008-05-07 22:45:20
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Translated. sorry for the italian comments that are surviving in a lot of places... skunkwerk wrote: > i'm using a CMesh0::FaceIterator but it seems like it's a const for > some reason - when I try to change values of the face, like > fit->cWT(0).N() i get compilation errors about 'assignment of > read-only location.' what's the proper way to modify these values? > > i was translating some of the italian comments in rect_packer.cpp but > couldn't find translations for the following: > posiziono - position? > pe plus' > could someone please translate these to english for me? > > thanks > imran > > On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm... > <mailto:sku...@gm...>> wrote: > > thanks Paolo, > i guess CMesh0 is how i'll get the faceiterator - i'm working > on some collada importer optimizations right now but might get > back to this in a few days. what options do we have for a > numerical solver? > > imran > > > On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > I like your proposal, but I strongly suggest you to proceed > gradually and start and complete and test a functionality at a > time. > > First of all start to just add a simple rectangular packer, > > - then try to use the rect_packer provided code > > - then try to look at the code in the > trimesh/textcoord_optimization.h file. > > Before facing LSCM we should solve the issue of what numerical > solver use for it and for other issues that we have around in > the vcg. > I hope we could take some decision in the next weeks about the > numeric solver in the vcg. > > I noticed that some notes on the basic types were missing so i > added it in > http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin > Feel also free to contribute to the wiki in the part about the > writing of the plugins when you see points needing some > clarification or a deeper discussion. > > > cheers > p. > > > > > > > > skunkwerk wrote: >> thanks for the hints paolo, >> i wanted to use this algorithm: >> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >> but it seemed like it needed information on the actual >> models, and was taking in arbitrarily-shaped textures. >> >> the only other algorithm i've found for texture packing is a >> recursive tree-based one: >> http://www.blackpawn.com/texts/lightmaps/default.html >> >> i tried this line (along with everything else i could think of): >> MeshModel::FaceIterator fit; >> but it didn't like the 'MeshModel' part - is 'mm' not an >> object of type MeshModel? >> >> if someone could suggest the correct syntax i can get started >> on testing the texture atlas >> >> thanks, >> imran >> >> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni >> <pao...@is... >> <mailto:pao...@is...>> wrote: >> >> skunkwerk wrote: >> > i've attached a texture atlas function. >> > >> > it compiles except for a ConstFaceIterator error - I've >> tried using >> > the template<typename MESHTYPE> but that didn't work >> either. the >> > algorithm is VERY basic (textures are added one after >> another in a >> > row), but should work. i couldn't find any algorithms >> for more >> > closely-packed positioning, but i could look at the code in >> > openscenegraph's texture atlas generator. >> Nice Job! >> >> The right place for this stuff is the filter_texture >> plugin that i have >> just added, >> Now it is just a placeholder filter you should add your >> code there. >> >> Important: >> In the plugin dir you can find a rect_packer that should >> make good job. >> please use it to build a good packing of the texture size >> >> > questions: >> > 1) if someone could tell me how to iterate through >> faces from a >> > function outside vcg, that'd be great so i could test >> this out >> We have started to improve the developer documentation: >> two new pages in >> the wiki should help you >> >> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >> >> > 2) paolo, what's the best location of this function? >> i'm currently >> > putting it in mainwindow_Runtime.cpp to test it out >> The right location is inside the filter_texture plugin >> possible parameter of the plugin: >> - format of the saved texture (as a enum) >> - max size of the texture >> >> > 3) how do I access the data from already-loaded >> textures? so i can >> > prevent having to load all the textures again... >> Do not worry about that. Feel free to use QT to load >> again the images >> and process them, it should not create a significant >> overhead. >> >> Once your processing is ended (and you have saved the new >> texture) you >> should update the texture names stored inside the mesh >> sending a signal >> to the updateTexture() slot of the mainwindow (the >> parent of the action) >> >> cheers >> p. >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni >> <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) >> Conference >> Don't miss this year's exciting event. There's still time >> to save $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> ------------------------------------------------------------------------ >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) >> Conference Don't miss this year's exciting event. There's >> still time to save $100. Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni > <http://vcg.isti.cnr.it/%7Ecignoni> ISTI - CNR Via Moruzzi 1, > 56124 Pisa ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to > save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-05-08 01:05:56
|
thanks paolo, any hints on why i can't modify faces with the iterator i'm using? am i using the wrong kind? i saw 'constfaceiterator' in the code somewhere, so I figured 'faceiterator' wouldn't be const. imran On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni <pao...@is...> wrote: > Translated. sorry for the italian comments that are surviving in a lot of > places... > > > > skunkwerk wrote: > > i'm using a CMesh0::FaceIterator but it seems like it's a const for some > reason - when I try to change values of the face, like fit->cWT(0).N() i get > compilation errors about 'assignment of read-only location.' what's the > proper way to modify these values? > > i was translating some of the italian comments in rect_packer.cpp but > couldn't find translations for the following: > posiziono - position? > pe plus' > could someone please translate these to english for me? > > thanks > imran > > On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> wrote: > > > thanks Paolo, > > i guess CMesh0 is how i'll get the faceiterator - i'm working on some > > collada importer optimizations right now but might get back to this in a few > > days. what options do we have for a numerical solver? > > > > imran > > > > On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni < > > pao...@is...> wrote: > > > > > I like your proposal, but I strongly suggest you to proceed gradually > > > and start and complete and test a functionality at a time. > > > > > > First of all start to just add a simple rectangular packer, > > > > > > - then try to use the rect_packer provided code > > > > > > - then try to look at the code in the trimesh/textcoord_optimization.h > > > file. > > > > > > Before facing LSCM we should solve the issue of what numerical solver > > > use for it and for other issues that we have around in the vcg. > > > I hope we could take some decision in the next weeks about the numeric > > > solver in the vcg. > > > > > > I noticed that some notes on the basic types were missing so i added > > > it in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin > > > Feel also free to contribute to the wiki in the part about the writing > > > of the plugins when you see points needing some clarification or a deeper > > > discussion. > > > > > > > > > cheers > > > p. > > > > > > > > > > > > > > > > > > > > > > > > skunkwerk wrote: > > > > > > thanks for the hints paolo, > > > i wanted to use this algorithm: > > > http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm > > > but it seemed like it needed information on the actual models, and was > > > taking in arbitrarily-shaped textures. > > > > > > the only other algorithm i've found for texture packing is a recursive > > > tree-based one: > > > http://www.blackpawn.com/texts/lightmaps/default.html > > > > > > i tried this line (along with everything else i could think of): > > > MeshModel::FaceIterator fit; > > > but it didn't like the 'MeshModel' part - is 'mm' not an object of > > > type MeshModel? > > > > > > if someone could suggest the correct syntax i can get started on > > > testing the texture atlas > > > > > > thanks, > > > imran > > > > > > On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < > > > pao...@is...> wrote: > > > > > > skunkwerk wrote: > > > > i've attached a texture atlas function. > > > > > > > > it compiles except for a ConstFaceIterator error - I've tried using > > > > the template<typename MESHTYPE> but that didn't work either. the > > > > algorithm is VERY basic (textures are added one after another in a > > > > row), but should work. i couldn't find any algorithms for more > > > > closely-packed positioning, but i could look at the code in > > > > openscenegraph's texture atlas generator. > > > Nice Job! > > > > > > The right place for this stuff is the filter_texture plugin that i > > > have > > > just added, > > > Now it is just a placeholder filter you should add your code there. > > > > > > Important: > > > In the plugin dir you can find a rect_packer that should make good > > > job. > > > please use it to build a good packing of the texture size > > > > > > > questions: > > > > 1) if someone could tell me how to iterate through faces from a > > > > function outside vcg, that'd be great so i could test this out > > > We have started to improve the developer documentation: two new pages > > > in > > > the wiki should help you > > > > > > http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh > > > http://meshlab.sourceforge.net/wiki/index.php/Algorithms > > > > > > > 2) paolo, what's the best location of this function? i'm currently > > > > putting it in mainwindow_Runtime.cpp to test it out > > > The right location is inside the filter_texture plugin > > > possible parameter of the plugin: > > > - format of the saved texture (as a enum) > > > - max size of the texture > > > > > > > 3) how do I access the data from already-loaded textures? so i can > > > > prevent having to load all the textures again... > > > Do not worry about that. Feel free to use QT to load again the images > > > and process them, it should not create a significant overhead. > > > > > > Once your processing is ended (and you have saved the new texture) > > > you > > > should update the texture names stored inside the mesh sending a > > > signal > > > to the updateTexture() slot of the mainwindow (the parent of the > > > action) > > > > > > cheers > > > p. > > > > > > -- > > > Paolo Cignoni -- Senior Researcher > > > Visual Computing Laboratory - ISTI - CNR > > > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > > > > > ISTI - CNR > > > Via Moruzzi 1, > > > 56124 Pisa > > > ITALY > > > > > > > > > > > > ------------------------------------------------------------------------- > > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > > Don't miss this year's exciting event. There's still time to save > > > $100. > > > Use priority code J8TL2D2. > > > > > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > > _______________________________________________ > > > Meshlab-devel mailing list > > > Mes...@li... > > > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > > > > > ------------------------------ > > > > > > ------------------------------------------------------------------------- > > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > > Don't miss this year's exciting event. There's still time to save $100. > > > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > > > > > ------------------------------ > > > > > > _______________________________________________ > > > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > > > > > > > > -- > > > Paolo Cignoni -- Senior Researcher > > > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > > > > > ISTI - CNR > > > Via Moruzzi 1, > > > 56124 Pisa > > > ITALY > > > > > > > > > > > > ------------------------------------------------------------------------- > > > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > > > Don't miss this year's exciting event. There's still time to save > > > $100. > > > Use priority code J8TL2D2. > > > > > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > > _______________________________________________ > > > Meshlab-devel mailing list > > > Mes...@li... > > > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > > > > > > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
|
From: Paolo C. <pao...@is...> - 2008-05-08 07:36:10
|
fit->cWT(0).N() the small c before WT means that you are asking for a constant access so you can read the values inside WT but you cannot change them. you should use something like fit->WT(0).N() obviously assuming that fit is not a constfaceiterator. We are building up some tutorial on the vcg foundations you can find a first draft at http://vcg.sourceforge.net/mediawiki/index.php/Tutorial p. skunkwerk wrote: > thanks paolo, > any hints on why i can't modify faces with the iterator i'm using? > am i using the wrong kind? i saw 'constfaceiterator' in the code > somewhere, so I figured 'faceiterator' wouldn't be const. > > imran > > On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > Translated. sorry for the italian comments that are surviving in a > lot of places... > > > > skunkwerk wrote: >> i'm using a CMesh0::FaceIterator but it seems like it's a const >> for some reason - when I try to change values of the face, like >> fit->cWT(0).N() i get compilation errors about 'assignment of >> read-only location.' what's the proper way to modify these values? >> >> i was translating some of the italian comments in rect_packer.cpp >> but couldn't find translations for the following: >> posiziono - position? >> pe plus' >> could someone please translate these to english for me? >> >> thanks >> imran >> >> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm... >> <mailto:sku...@gm...>> wrote: >> >> thanks Paolo, >> i guess CMesh0 is how i'll get the faceiterator - i'm >> working on some collada importer optimizations right now but >> might get back to this in a few days. what options do we >> have for a numerical solver? >> >> imran >> >> >> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni >> <pao...@is... >> <mailto:pao...@is...>> wrote: >> >> I like your proposal, but I strongly suggest you to >> proceed gradually and start and complete and test a >> functionality at a time. >> >> First of all start to just add a simple rectangular packer, >> >> - then try to use the rect_packer provided code >> >> - then try to look at the code in the >> trimesh/textcoord_optimization.h file. >> >> Before facing LSCM we should solve the issue of what >> numerical solver use for it and for other issues that we >> have around in the vcg. >> I hope we could take some decision in the next weeks >> about the numeric solver in the vcg. >> >> I noticed that some notes on the basic types were missing >> so i added it in >> http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >> Feel also free to contribute to the wiki in the part >> about the writing of the plugins when you see points >> needing some clarification or a deeper discussion. >> >> >> cheers >> p. >> >> >> >> >> >> >> >> skunkwerk wrote: >>> thanks for the hints paolo, >>> i wanted to use this algorithm: >>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>> but it seemed like it needed information on the actual >>> models, and was taking in arbitrarily-shaped textures. >>> >>> the only other algorithm i've found for texture packing >>> is a recursive tree-based one: >>> http://www.blackpawn.com/texts/lightmaps/default.html >>> >>> i tried this line (along with everything else i could >>> think of): >>> MeshModel::FaceIterator fit; >>> but it didn't like the 'MeshModel' part - is 'mm' not an >>> object of type MeshModel? >>> >>> if someone could suggest the correct syntax i can get >>> started on testing the texture atlas >>> >>> thanks, >>> imran >>> >>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni >>> <pao...@is... >>> <mailto:pao...@is...>> wrote: >>> >>> skunkwerk wrote: >>> > i've attached a texture atlas function. >>> > >>> > it compiles except for a ConstFaceIterator error - >>> I've tried using >>> > the template<typename MESHTYPE> but that didn't >>> work either. the >>> > algorithm is VERY basic (textures are added one >>> after another in a >>> > row), but should work. i couldn't find any >>> algorithms for more >>> > closely-packed positioning, but i could look at >>> the code in >>> > openscenegraph's texture atlas generator. >>> Nice Job! >>> >>> The right place for this stuff is the filter_texture >>> plugin that i have >>> just added, >>> Now it is just a placeholder filter you should add >>> your code there. >>> >>> Important: >>> In the plugin dir you can find a rect_packer that >>> should make good job. >>> please use it to build a good packing of the texture >>> size >>> >>> > questions: >>> > 1) if someone could tell me how to iterate >>> through faces from a >>> > function outside vcg, that'd be great so i could >>> test this out >>> We have started to improve the developer >>> documentation: two new pages in >>> the wiki should help you >>> >>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>> >>> > 2) paolo, what's the best location of this >>> function? i'm currently >>> > putting it in mainwindow_Runtime.cpp to test it out >>> The right location is inside the filter_texture plugin >>> possible parameter of the plugin: >>> - format of the saved texture (as a enum) >>> - max size of the texture >>> >>> > 3) how do I access the data from already-loaded >>> textures? so i can >>> > prevent having to load all the textures again... >>> Do not worry about that. Feel free to use QT to load >>> again the images >>> and process them, it should not create a significant >>> overhead. >>> >>> Once your processing is ended (and you have saved >>> the new texture) you >>> should update the texture names stored inside the >>> mesh sending a signal >>> to the updateTexture() slot of the mainwindow (the >>> parent of the action) >>> >>> cheers >>> p. >>> >>> -- >>> Paolo Cignoni -- Senior Researcher >>> Visual Computing Laboratory - ISTI - CNR >>> http://vcg.isti.cnr.it/~cignoni >>> <http://vcg.isti.cnr.it/%7Ecignoni> >>> >>> ISTI - CNR >>> Via Moruzzi 1, >>> 56124 Pisa >>> ITALY >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 >>> JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still >>> time to save $100. >>> Use priority code J8TL2D2. >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... >>> <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >>> ------------------------------------------------------------------------ >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) >>> Conference Don't miss this year's exciting event. >>> There's still time to save $100. Use priority code >>> J8TL2D2. >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> >>> ------------------------------------------------------------------------ >>> >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni >> <http://vcg.isti.cnr.it/%7Ecignoni> ISTI - CNR Via >> Moruzzi 1, 56124 Pisa ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) >> Conference >> Don't miss this year's exciting event. There's still time >> to save $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save > $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-05-08 19:31:06
|
thanks Paolo, that solved the immediate problem. I'm having trouble compiling, though. the error i'm getting is: release/moc_filter_texture.o:(.data.rel.ro._ZTV19FilterTexturePlugin[vtable for FilterTexturePlugin]+0x4c): undefined reference to `FilterTexturePlugin::applyFilter(QAction*, MeshModel&, FilterParameterSet&, bool (*)(int, char const*))' I changed the function definition from the above to applyFilter(QAction *filter, MeshModel &m, FilterParameterSet &par, vcg::CallBackPos * cb) but can't figure out where the old definition is still present, as the .h file has the same definition. any ideas? thanks imran On Thu, May 8, 2008 at 12:35 AM, Paolo Cignoni <pao...@is...> wrote: > fit->cWT(0).N() > the small c before WT means that you are asking for a constant access so > you can read the values inside WT but you cannot change them. > you should use something like fit->WT(0).N() obviously assuming that fit is > not a constfaceiterator. > > We are building up some tutorial on the vcg foundations you can find a > first draft at > > http://vcg.sourceforge.net/mediawiki/index.php/Tutorial > > p. > > > > > skunkwerk wrote: > > thanks paolo, > any hints on why i can't modify faces with the iterator i'm using? am i > using the wrong kind? i saw 'constfaceiterator' in the code somewhere, so I > figured 'faceiterator' wouldn't be const. > > imran > > On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni <pao...@is...> > wrote: > >> Translated. sorry for the italian comments that are surviving in a lot of >> places... >> >> >> skunkwerk wrote: >> >> i'm using a CMesh0::FaceIterator but it seems like it's a const for some >> reason - when I try to change values of the face, like fit->cWT(0).N() i get >> compilation errors about 'assignment of read-only location.' what's the >> proper way to modify these values? >> >> i was translating some of the italian comments in rect_packer.cpp but >> couldn't find translations for the following: >> posiziono - position? >> pe plus' >> could someone please translate these to english for me? >> >> thanks >> imran >> >> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> wrote: >> >>> thanks Paolo, >>> i guess CMesh0 is how i'll get the faceiterator - i'm working on some >>> collada importer optimizations right now but might get back to this in a few >>> days. what options do we have for a numerical solver? >>> >>> imran >>> >>> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni < >>> pao...@is...> wrote: >>> >>>> I like your proposal, but I strongly suggest you to proceed gradually >>>> and start and complete and test a functionality at a time. >>>> >>>> First of all start to just add a simple rectangular packer, >>>> >>>> - then try to use the rect_packer provided code >>>> >>>> - then try to look at the code in the trimesh/textcoord_optimization.h >>>> file. >>>> >>>> Before facing LSCM we should solve the issue of what numerical solver >>>> use for it and for other issues that we have around in the vcg. >>>> I hope we could take some decision in the next weeks about the numeric >>>> solver in the vcg. >>>> >>>> I noticed that some notes on the basic types were missing so i added it >>>> in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >>>> Feel also free to contribute to the wiki in the part about the writing >>>> of the plugins when you see points needing some clarification or a deeper >>>> discussion. >>>> >>>> >>>> cheers >>>> p. >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> skunkwerk wrote: >>>> >>>> thanks for the hints paolo, >>>> i wanted to use this algorithm: >>>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>>> but it seemed like it needed information on the actual models, and was >>>> taking in arbitrarily-shaped textures. >>>> >>>> the only other algorithm i've found for texture packing is a recursive >>>> tree-based one: >>>> http://www.blackpawn.com/texts/lightmaps/default.html >>>> >>>> i tried this line (along with everything else i could think of): >>>> MeshModel::FaceIterator fit; >>>> but it didn't like the 'MeshModel' part - is 'mm' not an object of type >>>> MeshModel? >>>> >>>> if someone could suggest the correct syntax i can get started on testing >>>> the texture atlas >>>> >>>> thanks, >>>> imran >>>> >>>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < >>>> pao...@is...> wrote: >>>> >>>> skunkwerk wrote: >>>> > i've attached a texture atlas function. >>>> > >>>> > it compiles except for a ConstFaceIterator error - I've tried using >>>> > the template<typename MESHTYPE> but that didn't work either. the >>>> > algorithm is VERY basic (textures are added one after another in a >>>> > row), but should work. i couldn't find any algorithms for more >>>> > closely-packed positioning, but i could look at the code in >>>> > openscenegraph's texture atlas generator. >>>> Nice Job! >>>> >>>> The right place for this stuff is the filter_texture plugin that i have >>>> just added, >>>> Now it is just a placeholder filter you should add your code there. >>>> >>>> Important: >>>> In the plugin dir you can find a rect_packer that should make good job. >>>> please use it to build a good packing of the texture size >>>> >>>> > questions: >>>> > 1) if someone could tell me how to iterate through faces from a >>>> > function outside vcg, that'd be great so i could test this out >>>> We have started to improve the developer documentation: two new pages >>>> in >>>> the wiki should help you >>>> >>>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>>> >>>> > 2) paolo, what's the best location of this function? i'm currently >>>> > putting it in mainwindow_Runtime.cpp to test it out >>>> The right location is inside the filter_texture plugin >>>> possible parameter of the plugin: >>>> - format of the saved texture (as a enum) >>>> - max size of the texture >>>> >>>> > 3) how do I access the data from already-loaded textures? so i can >>>> > prevent having to load all the textures again... >>>> Do not worry about that. Feel free to use QT to load again the images >>>> and process them, it should not create a significant overhead. >>>> >>>> Once your processing is ended (and you have saved the new texture) you >>>> should update the texture names stored inside the mesh sending a signal >>>> to the updateTexture() slot of the mainwindow (the parent of the >>>> action) >>>> >>>> cheers >>>> p. >>>> >>>> -- >>>> Paolo Cignoni -- Senior Researcher >>>> Visual Computing Laboratory - ISTI - CNR >>>> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>> >>>> ISTI - CNR >>>> Via Moruzzi 1, >>>> 56124 Pisa >>>> ITALY >>>> >>>> >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. >>>> >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>>> ------------------------------ >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> >>>> ------------------------------ >>>> >>>> _______________________________________________ >>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>>> >>>> -- >>>> Paolo Cignoni -- Senior Researcher >>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>> >>>> ISTI - CNR >>>> Via Moruzzi 1, >>>> 56124 Pisa >>>> ITALY >>>> >>>> >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. >>>> >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>> >> ------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. >> >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
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From: skunkwerk <sku...@gm...> - 2008-05-10 19:56:56
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i've committed the version of the filter_texture code i was trying to compile. can anyone try to compile this? i'll keep working on it imran On Thu, May 8, 2008 at 11:08 AM, skunkwerk <sku...@gm...> wrote: > thanks Paolo, that solved the immediate problem. I'm having trouble > compiling, though. the error i'm getting is: > > release/moc_filter_texture.o:(.data.rel.ro._ZTV19FilterTexturePlugin[vtable > for FilterTexturePlugin]+0x4c): undefined reference to > `FilterTexturePlugin::applyFilter(QAction*, MeshModel&, FilterParameterSet&, > bool (*)(int, char const*))' > > I changed the function definition from the above to applyFilter(QAction > *filter, MeshModel &m, FilterParameterSet &par, vcg::CallBackPos * cb) but > can't figure out where the old definition is still present, as the .h file > has the same definition. > > any ideas? > thanks > imran > > > On Thu, May 8, 2008 at 12:35 AM, Paolo Cignoni <pao...@is...> > wrote: > >> fit->cWT(0).N() >> the small c before WT means that you are asking for a constant access so >> you can read the values inside WT but you cannot change them. >> you should use something like fit->WT(0).N() obviously assuming that fit >> is not a constfaceiterator. >> >> We are building up some tutorial on the vcg foundations you can find a >> first draft at >> >> http://vcg.sourceforge.net/mediawiki/index.php/Tutorial >> >> p. >> >> >> >> >> skunkwerk wrote: >> >> thanks paolo, >> any hints on why i can't modify faces with the iterator i'm using? am >> i using the wrong kind? i saw 'constfaceiterator' in the code somewhere, so >> I figured 'faceiterator' wouldn't be const. >> >> imran >> >> On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni <pao...@is...> >> wrote: >> >>> Translated. sorry for the italian comments that are surviving in a lot of >>> places... >>> >>> >>> skunkwerk wrote: >>> >>> i'm using a CMesh0::FaceIterator but it seems like it's a const for some >>> reason - when I try to change values of the face, like fit->cWT(0).N() i get >>> compilation errors about 'assignment of read-only location.' what's the >>> proper way to modify these values? >>> >>> i was translating some of the italian comments in rect_packer.cpp but >>> couldn't find translations for the following: >>> posiziono - position? >>> pe plus' >>> could someone please translate these to english for me? >>> >>> thanks >>> imran >>> >>> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> wrote: >>> >>>> thanks Paolo, >>>> i guess CMesh0 is how i'll get the faceiterator - i'm working on some >>>> collada importer optimizations right now but might get back to this in a few >>>> days. what options do we have for a numerical solver? >>>> >>>> imran >>>> >>>> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni < >>>> pao...@is...> wrote: >>>> >>>>> I like your proposal, but I strongly suggest you to proceed gradually >>>>> and start and complete and test a functionality at a time. >>>>> >>>>> First of all start to just add a simple rectangular packer, >>>>> >>>>> - then try to use the rect_packer provided code >>>>> >>>>> - then try to look at the code in the trimesh/textcoord_optimization.h >>>>> file. >>>>> >>>>> Before facing LSCM we should solve the issue of what numerical solver >>>>> use for it and for other issues that we have around in the vcg. >>>>> I hope we could take some decision in the next weeks about the numeric >>>>> solver in the vcg. >>>>> >>>>> I noticed that some notes on the basic types were missing so i added it >>>>> in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >>>>> Feel also free to contribute to the wiki in the part about the writing >>>>> of the plugins when you see points needing some clarification or a deeper >>>>> discussion. >>>>> >>>>> >>>>> cheers >>>>> p. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> skunkwerk wrote: >>>>> >>>>> thanks for the hints paolo, >>>>> i wanted to use this algorithm: >>>>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>>>> but it seemed like it needed information on the actual models, and was >>>>> taking in arbitrarily-shaped textures. >>>>> >>>>> the only other algorithm i've found for texture packing is a recursive >>>>> tree-based one: >>>>> http://www.blackpawn.com/texts/lightmaps/default.html >>>>> >>>>> i tried this line (along with everything else i could think of): >>>>> MeshModel::FaceIterator fit; >>>>> but it didn't like the 'MeshModel' part - is 'mm' not an object of type >>>>> MeshModel? >>>>> >>>>> if someone could suggest the correct syntax i can get started on >>>>> testing the texture atlas >>>>> >>>>> thanks, >>>>> imran >>>>> >>>>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < >>>>> pao...@is...> wrote: >>>>> >>>>> skunkwerk wrote: >>>>> > i've attached a texture atlas function. >>>>> > >>>>> > it compiles except for a ConstFaceIterator error - I've tried using >>>>> > the template<typename MESHTYPE> but that didn't work either. the >>>>> > algorithm is VERY basic (textures are added one after another in a >>>>> > row), but should work. i couldn't find any algorithms for more >>>>> > closely-packed positioning, but i could look at the code in >>>>> > openscenegraph's texture atlas generator. >>>>> Nice Job! >>>>> >>>>> The right place for this stuff is the filter_texture plugin that i have >>>>> just added, >>>>> Now it is just a placeholder filter you should add your code there. >>>>> >>>>> Important: >>>>> In the plugin dir you can find a rect_packer that should make good job. >>>>> please use it to build a good packing of the texture size >>>>> >>>>> > questions: >>>>> > 1) if someone could tell me how to iterate through faces from a >>>>> > function outside vcg, that'd be great so i could test this out >>>>> We have started to improve the developer documentation: two new pages >>>>> in >>>>> the wiki should help you >>>>> >>>>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>>>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>>>> >>>>> > 2) paolo, what's the best location of this function? i'm currently >>>>> > putting it in mainwindow_Runtime.cpp to test it out >>>>> The right location is inside the filter_texture plugin >>>>> possible parameter of the plugin: >>>>> - format of the saved texture (as a enum) >>>>> - max size of the texture >>>>> >>>>> > 3) how do I access the data from already-loaded textures? so i can >>>>> > prevent having to load all the textures again... >>>>> Do not worry about that. Feel free to use QT to load again the images >>>>> and process them, it should not create a significant overhead. >>>>> >>>>> Once your processing is ended (and you have saved the new texture) you >>>>> should update the texture names stored inside the mesh sending a signal >>>>> to the updateTexture() slot of the mainwindow (the parent of the >>>>> action) >>>>> >>>>> cheers >>>>> p. >>>>> >>>>> -- >>>>> Paolo Cignoni -- Senior Researcher >>>>> Visual Computing Laboratory - ISTI - CNR >>>>> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>> >>>>> ISTI - CNR >>>>> Via Moruzzi 1, >>>>> 56124 Pisa >>>>> ITALY >>>>> >>>>> >>>>> >>>>> ------------------------------------------------------------------------- >>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>> Use priority code J8TL2D2. >>>>> >>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>> _______________________________________________ >>>>> Meshlab-devel mailing list >>>>> Mes...@li... >>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>> >>>>> >>>>> ------------------------------ >>>>> >>>>> ------------------------------------------------------------------------- >>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>> >>>>> ------------------------------ >>>>> >>>>> _______________________________________________ >>>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>> >>>>> >>>>> >>>>> -- >>>>> Paolo Cignoni -- Senior Researcher >>>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>> >>>>> ISTI - CNR >>>>> Via Moruzzi 1, >>>>> 56124 Pisa >>>>> ITALY >>>>> >>>>> >>>>> >>>>> ------------------------------------------------------------------------- >>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>> Use priority code J8TL2D2. >>>>> >>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>> _______________________________________________ >>>>> Meshlab-devel mailing list >>>>> Mes...@li... >>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>> >>>>> >>>> >>> ------------------------------ >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still time to save $100. >>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> >>> ------------------------------ >>> >>> _______________________________________________ >>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >>> >>> -- >>> Paolo Cignoni -- Senior Researcher >>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>> >>> ISTI - CNR >>> Via Moruzzi 1, >>> 56124 Pisa >>> ITALY >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still time to save $100. >>> Use priority code J8TL2D2. >>> >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >> ------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. >> >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> > |
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From: Paolo C. <pao...@is...> - 2008-05-11 07:02:52
|
Committed a compiling version. you forgot the name of the class in front of the implementation of the member function in your cpp. Added getclass and get requirements. Add in getRequirements what you need. Please try to structure a bit more the code. avoid to put everything inside the applyFilter function, that shoiuld be mostly a switch for all the incoming possible actions. Try to keep it short. cheers p. skunkwerk wrote: > i've committed the version of the filter_texture code i was trying to > compile. can anyone try to compile this? i'll keep working on it > > imran > > On Thu, May 8, 2008 at 11:08 AM, skunkwerk <sku...@gm... > <mailto:sku...@gm...>> wrote: > > thanks Paolo, that solved the immediate problem. I'm having > trouble compiling, though. the error i'm getting is: > > release/moc_filter_texture.o:(.data.rel.ro._ZTV19FilterTexturePlugin[vtable > for FilterTexturePlugin]+0x4c): undefined reference to > `FilterTexturePlugin::applyFilter(QAction*, MeshModel&, > FilterParameterSet&, bool (*)(int, char const*))' > > I changed the function definition from the above to > applyFilter(QAction *filter, MeshModel &m, FilterParameterSet > &par, vcg::CallBackPos * cb) but can't figure out where the old > definition is still present, as the .h file has the same definition. > > any ideas? > thanks > imran > > > On Thu, May 8, 2008 at 12:35 AM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > fit->cWT(0).N() > the small c before WT means that you are asking for a constant > access so you can read the values inside WT but you cannot > change them. > you should use something like fit->WT(0).N() obviously > assuming that fit is not a constfaceiterator. > > We are building up some tutorial on the vcg foundations you > can find a first draft at > > http://vcg.sourceforge.net/mediawiki/index.php/Tutorial > > p. > > > > > skunkwerk wrote: >> thanks paolo, >> any hints on why i can't modify faces with the iterator >> i'm using? am i using the wrong kind? i saw >> 'constfaceiterator' in the code somewhere, so I figured >> 'faceiterator' wouldn't be const. >> >> imran >> >> On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni >> <pao...@is... >> <mailto:pao...@is...>> wrote: >> >> Translated. sorry for the italian comments that are >> surviving in a lot of places... >> >> >> >> skunkwerk wrote: >>> i'm using a CMesh0::FaceIterator but it seems like it's >>> a const for some reason - when I try to change values of >>> the face, like fit->cWT(0).N() i get compilation errors >>> about 'assignment of read-only location.' what's the >>> proper way to modify these values? >>> >>> i was translating some of the italian comments in >>> rect_packer.cpp but couldn't find translations for the >>> following: >>> posiziono - position? >>> pe plus' >>> could someone please translate these to english for me? >>> >>> thanks >>> imran >>> >>> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk >>> <sku...@gm... <mailto:sku...@gm...>> wrote: >>> >>> thanks Paolo, >>> i guess CMesh0 is how i'll get the faceiterator - >>> i'm working on some collada importer optimizations >>> right now but might get back to this in a few days. >>> what options do we have for a numerical solver? >>> >>> imran >>> >>> >>> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni >>> <pao...@is... >>> <mailto:pao...@is...>> wrote: >>> >>> I like your proposal, but I strongly suggest you >>> to proceed gradually and start and complete and >>> test a functionality at a time. >>> >>> First of all start to just add a simple >>> rectangular packer, >>> >>> - then try to use the rect_packer provided code >>> >>> - then try to look at the code in the >>> trimesh/textcoord_optimization.h file. >>> >>> Before facing LSCM we should solve the issue of >>> what numerical solver use for it and for other >>> issues that we have around in the vcg. >>> I hope we could take some decision in the next >>> weeks about the numeric solver in the vcg. >>> >>> I noticed that some notes on the basic types >>> were missing so i added it in >>> http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >>> Feel also free to contribute to the wiki in the >>> part about the writing of the plugins when you >>> see points needing some clarification or a >>> deeper discussion. >>> >>> >>> cheers >>> p. >>> >>> >>> >>> >>> >>> >>> >>> skunkwerk wrote: >>>> thanks for the hints paolo, >>>> i wanted to use this algorithm: >>>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>>> but it seemed like it needed information on the >>>> actual models, and was taking in >>>> arbitrarily-shaped textures. >>>> >>>> the only other algorithm i've found for texture >>>> packing is a recursive tree-based one: >>>> http://www.blackpawn.com/texts/lightmaps/default.html >>>> >>>> i tried this line (along with everything else i >>>> could think of): >>>> MeshModel::FaceIterator fit; >>>> but it didn't like the 'MeshModel' part - is >>>> 'mm' not an object of type MeshModel? >>>> >>>> if someone could suggest the correct syntax i >>>> can get started on testing the texture atlas >>>> >>>> thanks, >>>> imran >>>> >>>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni >>>> <pao...@is... >>>> <mailto:pao...@is...>> wrote: >>>> >>>> skunkwerk wrote: >>>> > i've attached a texture atlas function. >>>> > >>>> > it compiles except for a >>>> ConstFaceIterator error - I've tried using >>>> > the template<typename MESHTYPE> but that >>>> didn't work either. the >>>> > algorithm is VERY basic (textures are >>>> added one after another in a >>>> > row), but should work. i couldn't find >>>> any algorithms for more >>>> > closely-packed positioning, but i could >>>> look at the code in >>>> > openscenegraph's texture atlas generator. >>>> Nice Job! >>>> >>>> The right place for this stuff is the >>>> filter_texture plugin that i have >>>> just added, >>>> Now it is just a placeholder filter you >>>> should add your code there. >>>> >>>> Important: >>>> In the plugin dir you can find a >>>> rect_packer that should make good job. >>>> please use it to build a good packing of >>>> the texture size >>>> >>>> > questions: >>>> > 1) if someone could tell me how to >>>> iterate through faces from a >>>> > function outside vcg, that'd be great so >>>> i could test this out >>>> We have started to improve the developer >>>> documentation: two new pages in >>>> the wiki should help you >>>> >>>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>>> >>>> > 2) paolo, what's the best location of >>>> this function? i'm currently >>>> > putting it in mainwindow_Runtime.cpp to >>>> test it out >>>> The right location is inside the >>>> filter_texture plugin >>>> possible parameter of the plugin: >>>> - format of the saved texture (as a enum) >>>> - max size of the texture >>>> >>>> > 3) how do I access the data from >>>> already-loaded textures? so i can >>>> > prevent having to load all the textures >>>> again... >>>> Do not worry about that. Feel free to use >>>> QT to load again the images >>>> and process them, it should not create a >>>> significant overhead. >>>> >>>> Once your processing is ended (and you have >>>> saved the new texture) you >>>> should update the texture names stored >>>> inside the mesh sending a signal >>>> to the updateTexture() slot of the >>>> mainwindow (the parent of the action) >>>> >>>> cheers >>>> p. >>>> >>>> -- >>>> Paolo Cignoni -- Senior Researcher >>>> Visual Computing Laboratory - ISTI - CNR >>>> http://vcg.isti.cnr.it/~cignoni >>>> <http://vcg.isti.cnr.it/%7Ecignoni> >>>> >>>> ISTI - CNR >>>> Via Moruzzi 1, >>>> 56124 Pisa >>>> ITALY >>>> >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 >>>> JavaOne(SM) Conference >>>> Don't miss this year's exciting event. >>>> There's still time to save $100. >>>> Use priority code J8TL2D2. >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... >>>> <mailto:Mes...@li...> >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>>> ------------------------------------------------------------------------ >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 >>>> JavaOne(SM) Conference Don't miss this year's >>>> exciting event. There's still time to save >>>> $100. Use priority code J8TL2D2. >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> >>>> ------------------------------------------------------------------------ >>>> >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... <mailto:Mes...@li...> >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>> >>> >>> -- >>> Paolo Cignoni -- Senior Researcher >>> Visual Computing Laboratory - ISTI - CNR >>> http://vcg.isti.cnr.it/~cignoni >>> <http://vcg.isti.cnr.it/%7Ecignoni> ISTI - CNR >>> Via Moruzzi 1, 56124 Pisa ITALY >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 >>> JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's >>> still time to save $100. >>> Use priority code J8TL2D2. >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... >>> <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >>> >>> ------------------------------------------------------------------------ >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still time to save $100. >>> Use priority code J8TL2D2. >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> >>> ------------------------------------------------------------------------ >>> >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) >> Conference >> Don't miss this year's exciting event. There's still time >> to save $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> ------------------------------------------------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to > save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
|
From: skunkwerk <sku...@gm...> - 2008-05-18 17:53:33
|
thanks Paolo, sorry - i should have caught that. I'm testing out the code right now, and I need confirmation of UV coordinate formats: 1) if the coordinates are >1 that means the textures are to be repeated/tiled, correct? but meshlab can handle this, I don't need to change anything. 2) what do negative uv coordinates mean? I assumed the origin (0,0) was at the top-left corner of the textures. I don't see how you could have negative uv coordinates (as i'm seeing in some models) unless the origin is in the center. cheers, imran 2008/5/11 Paolo Cignoni <pao...@is...>: > Committed a compiling version. > you forgot the name of the class in front of the implementation of the > member function in your cpp. > Added getclass and get requirements. Add in getRequirements what you need. > > Please try to structure a bit more the code. > avoid to put everything inside the applyFilter function, that shoiuld be > mostly a switch for all the incoming possible actions. > > Try to keep it short. > > cheers p. > > > > skunkwerk wrote: > > i've committed the version of the filter_texture code i was trying to > compile. can anyone try to compile this? i'll keep working on it > > imran > > On Thu, May 8, 2008 at 11:08 AM, skunkwerk <sku...@gm...> wrote: > >> thanks Paolo, that solved the immediate problem. I'm having trouble >> compiling, though. the error i'm getting is: >> >> release/moc_filter_texture.o:(.data.rel.ro._ZTV19FilterTexturePlugin[vtable >> for FilterTexturePlugin]+0x4c): undefined reference to >> `FilterTexturePlugin::applyFilter(QAction*, MeshModel&, FilterParameterSet&, >> bool (*)(int, char const*))' >> >> I changed the function definition from the above to applyFilter(QAction >> *filter, MeshModel &m, FilterParameterSet &par, vcg::CallBackPos * cb) but >> can't figure out where the old definition is still present, as the .h file >> has the same definition. >> >> any ideas? >> thanks >> imran >> >> On Thu, May 8, 2008 at 12:35 AM, Paolo Cignoni <pao...@is...> >> wrote: >> >>> fit->cWT(0).N() >>> the small c before WT means that you are asking for a constant access so >>> you can read the values inside WT but you cannot change them. >>> you should use something like fit->WT(0).N() obviously assuming that fit >>> is not a constfaceiterator. >>> >>> We are building up some tutorial on the vcg foundations you can find a >>> first draft at >>> >>> http://vcg.sourceforge.net/mediawiki/index.php/Tutorial >>> >>> p. >>> >>> >>> >>> skunkwerk wrote: >>> >>> thanks paolo, >>> any hints on why i can't modify faces with the iterator i'm using? am >>> i using the wrong kind? i saw 'constfaceiterator' in the code somewhere, so >>> I figured 'faceiterator' wouldn't be const. >>> >>> imran >>> >>> On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni <pao...@is...> >>> wrote: >>> >>>> Translated. sorry for the italian comments that are surviving in a lot >>>> of places... >>>> >>>> >>>> skunkwerk wrote: >>>> >>>> i'm using a CMesh0::FaceIterator but it seems like it's a const for some >>>> reason - when I try to change values of the face, like fit->cWT(0).N() i get >>>> compilation errors about 'assignment of read-only location.' what's the >>>> proper way to modify these values? >>>> >>>> i was translating some of the italian comments in rect_packer.cpp but >>>> couldn't find translations for the following: >>>> posiziono - position? >>>> pe plus' >>>> could someone please translate these to english for me? >>>> >>>> thanks >>>> imran >>>> >>>> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> >>>> wrote: >>>> >>>>> thanks Paolo, >>>>> i guess CMesh0 is how i'll get the faceiterator - i'm working on >>>>> some collada importer optimizations right now but might get back to this in >>>>> a few days. what options do we have for a numerical solver? >>>>> >>>>> imran >>>>> >>>>> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni < >>>>> pao...@is...> wrote: >>>>> >>>>>> I like your proposal, but I strongly suggest you to proceed gradually >>>>>> and start and complete and test a functionality at a time. >>>>>> >>>>>> First of all start to just add a simple rectangular packer, >>>>>> >>>>>> - then try to use the rect_packer provided code >>>>>> >>>>>> - then try to look at the code in the trimesh/textcoord_optimization.h >>>>>> file. >>>>>> >>>>>> Before facing LSCM we should solve the issue of what numerical solver >>>>>> use for it and for other issues that we have around in the vcg. >>>>>> I hope we could take some decision in the next weeks about the numeric >>>>>> solver in the vcg. >>>>>> >>>>>> I noticed that some notes on the basic types were missing so i added >>>>>> it in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >>>>>> Feel also free to contribute to the wiki in the part about the writing >>>>>> of the plugins when you see points needing some clarification or a deeper >>>>>> discussion. >>>>>> >>>>>> >>>>>> cheers >>>>>> p. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> skunkwerk wrote: >>>>>> >>>>>> thanks for the hints paolo, >>>>>> i wanted to use this algorithm: >>>>>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>>>>> but it seemed like it needed information on the actual models, and was >>>>>> taking in arbitrarily-shaped textures. >>>>>> >>>>>> the only other algorithm i've found for texture packing is a recursive >>>>>> tree-based one: >>>>>> http://www.blackpawn.com/texts/lightmaps/default.html >>>>>> >>>>>> i tried this line (along with everything else i could think of): >>>>>> MeshModel::FaceIterator fit; >>>>>> but it didn't like the 'MeshModel' part - is 'mm' not an object of >>>>>> type MeshModel? >>>>>> >>>>>> if someone could suggest the correct syntax i can get started on >>>>>> testing the texture atlas >>>>>> >>>>>> thanks, >>>>>> imran >>>>>> >>>>>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < >>>>>> pao...@is...> wrote: >>>>>> >>>>>> skunkwerk wrote: >>>>>> > i've attached a texture atlas function. >>>>>> > >>>>>> > it compiles except for a ConstFaceIterator error - I've tried using >>>>>> > the template<typename MESHTYPE> but that didn't work either. the >>>>>> > algorithm is VERY basic (textures are added one after another in a >>>>>> > row), but should work. i couldn't find any algorithms for more >>>>>> > closely-packed positioning, but i could look at the code in >>>>>> > openscenegraph's texture atlas generator. >>>>>> Nice Job! >>>>>> >>>>>> The right place for this stuff is the filter_texture plugin that i >>>>>> have >>>>>> just added, >>>>>> Now it is just a placeholder filter you should add your code there. >>>>>> >>>>>> Important: >>>>>> In the plugin dir you can find a rect_packer that should make good >>>>>> job. >>>>>> please use it to build a good packing of the texture size >>>>>> >>>>>> > questions: >>>>>> > 1) if someone could tell me how to iterate through faces from a >>>>>> > function outside vcg, that'd be great so i could test this out >>>>>> We have started to improve the developer documentation: two new pages >>>>>> in >>>>>> the wiki should help you >>>>>> >>>>>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>>>>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>>>>> >>>>>> > 2) paolo, what's the best location of this function? i'm currently >>>>>> > putting it in mainwindow_Runtime.cpp to test it out >>>>>> The right location is inside the filter_texture plugin >>>>>> possible parameter of the plugin: >>>>>> - format of the saved texture (as a enum) >>>>>> - max size of the texture >>>>>> >>>>>> > 3) how do I access the data from already-loaded textures? so i can >>>>>> > prevent having to load all the textures again... >>>>>> Do not worry about that. Feel free to use QT to load again the images >>>>>> and process them, it should not create a significant overhead. >>>>>> >>>>>> Once your processing is ended (and you have saved the new texture) >>>>>> you >>>>>> should update the texture names stored inside the mesh sending a >>>>>> signal >>>>>> to the updateTexture() slot of the mainwindow (the parent of the >>>>>> action) >>>>>> >>>>>> cheers >>>>>> p. >>>>>> >>>>>> -- >>>>>> Paolo Cignoni -- Senior Researcher >>>>>> Visual Computing Laboratory - ISTI - CNR >>>>>> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>>> >>>>>> ISTI - CNR >>>>>> Via Moruzzi 1, >>>>>> 56124 Pisa >>>>>> ITALY >>>>>> >>>>>> >>>>>> >>>>>> ------------------------------------------------------------------------- >>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>> Don't miss this year's exciting event. There's still time to save >>>>>> $100. >>>>>> Use priority code J8TL2D2. >>>>>> >>>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>> _______________________________________________ >>>>>> Meshlab-devel mailing list >>>>>> Mes...@li... >>>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>> >>>>>> >>>>>> ------------------------------ >>>>>> >>>>>> ------------------------------------------------------------------------- >>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>> >>>>>> ------------------------------ >>>>>> >>>>>> _______________________________________________ >>>>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Paolo Cignoni -- Senior Researcher >>>>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>>> >>>>>> ISTI - CNR >>>>>> Via Moruzzi 1, >>>>>> 56124 Pisa >>>>>> ITALY >>>>>> >>>>>> >>>>>> >>>>>> ------------------------------------------------------------------------- >>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>> Don't miss this year's exciting event. There's still time to save >>>>>> $100. >>>>>> Use priority code J8TL2D2. >>>>>> >>>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>> _______________________________________________ >>>>>> Meshlab-devel mailing list >>>>>> Mes...@li... >>>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>> >>>>>> >>>>> >>>> ------------------------------ >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> >>>> ------------------------------ >>>> >>>> _______________________________________________ >>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>>> >>>> -- >>>> Paolo Cignoni -- Senior Researcher >>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>> >>>> ISTI - CNR >>>> Via Moruzzi 1, >>>> 56124 Pisa >>>> ITALY >>>> >>>> >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. >>>> >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>> ------------------------------ >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still time to save $100. >>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> >>> ------------------------------ >>> >>> _______________________________________________ >>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >>> >>> -- >>> Paolo Cignoni -- Senior Researcher >>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>> >>> ISTI - CNR >>> Via Moruzzi 1, >>> 56124 Pisa >>> ITALY >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>> Don't miss this year's exciting event. There's still time to save $100. >>> Use priority code J8TL2D2. >>> >>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >> > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
|
From: Imran A. <im...@os...> - 2008-05-18 23:11:26
|
i've committed a few changes to the filter_texture plugin that I needed to make it compile: syntax errors in rect_packer: the proper typedef for point2i is Point2i (capitalized P), and the include file to point2.h needed an absolute path added filter_texture.cpp to the filter_texture.pro file tried calling rect_packer::pack from the filter_texture.cpp file. is the following interpretation of the rect_packer::pack function correct: 1) 'sizes' is a vector of points corresponding to the width/height of each texture 2) 'max_size' is a single point that represents the maximum height/width of the texture atlas you want to create 3) 'posiz' is a vector of points that indicate for each texture in 'sizes', where to place this texture in the texture atlas (initially this would be empty) 4) 'global_size' represents the minimum height/width necessary to encompass the resulting texture atlas (initially null) suggestions? imran On Sun, May 18, 2008 at 10:53 AM, skunkwerk <sku...@gm...> wrote: > thanks Paolo, > sorry - i should have caught that. I'm testing out the code right now, > and I need confirmation of UV coordinate formats: > > 1) if the coordinates are >1 that means the textures are to be > repeated/tiled, correct? but meshlab can handle this, I don't need to > change anything. > 2) what do negative uv coordinates mean? I assumed the origin (0,0) was > at the top-left corner of the textures. I don't see how you could have > negative uv coordinates (as i'm seeing in some models) unless the origin is > in the center. > > cheers, > imran > > 2008/5/11 Paolo Cignoni <pao...@is...>: > > Committed a compiling version. >> you forgot the name of the class in front of the implementation of the >> member function in your cpp. >> Added getclass and get requirements. Add in getRequirements what you need. >> >> Please try to structure a bit more the code. >> avoid to put everything inside the applyFilter function, that shoiuld be >> mostly a switch for all the incoming possible actions. >> >> Try to keep it short. >> >> cheers p. >> >> >> >> skunkwerk wrote: >> >> i've committed the version of the filter_texture code i was trying to >> compile. can anyone try to compile this? i'll keep working on it >> >> imran >> >> On Thu, May 8, 2008 at 11:08 AM, skunkwerk <sku...@gm...> wrote: >> >>> thanks Paolo, that solved the immediate problem. I'm having trouble >>> compiling, though. the error i'm getting is: >>> >>> release/moc_filter_texture.o:(.data.rel.ro._ZTV19FilterTexturePlugin[vtable >>> for FilterTexturePlugin]+0x4c): undefined reference to >>> `FilterTexturePlugin::applyFilter(QAction*, MeshModel&, FilterParameterSet&, >>> bool (*)(int, char const*))' >>> >>> I changed the function definition from the above to applyFilter(QAction >>> *filter, MeshModel &m, FilterParameterSet &par, vcg::CallBackPos * cb) but >>> can't figure out where the old definition is still present, as the .h file >>> has the same definition. >>> >>> any ideas? >>> thanks >>> imran >>> >>> On Thu, May 8, 2008 at 12:35 AM, Paolo Cignoni < >>> pao...@is...> wrote: >>> >>>> fit->cWT(0).N() >>>> the small c before WT means that you are asking for a constant access so >>>> you can read the values inside WT but you cannot change them. >>>> you should use something like fit->WT(0).N() obviously assuming that fit >>>> is not a constfaceiterator. >>>> >>>> We are building up some tutorial on the vcg foundations you can find a >>>> first draft at >>>> >>>> http://vcg.sourceforge.net/mediawiki/index.php/Tutorial >>>> >>>> p. >>>> >>>> >>>> >>>> skunkwerk wrote: >>>> >>>> thanks paolo, >>>> any hints on why i can't modify faces with the iterator i'm using? >>>> am i using the wrong kind? i saw 'constfaceiterator' in the code somewhere, >>>> so I figured 'faceiterator' wouldn't be const. >>>> >>>> imran >>>> >>>> On Wed, May 7, 2008 at 3:44 PM, Paolo Cignoni < >>>> pao...@is...> wrote: >>>> >>>>> Translated. sorry for the italian comments that are surviving in a lot >>>>> of places... >>>>> >>>>> >>>>> skunkwerk wrote: >>>>> >>>>> i'm using a CMesh0::FaceIterator but it seems like it's a const for >>>>> some reason - when I try to change values of the face, like fit->cWT(0).N() >>>>> i get compilation errors about 'assignment of read-only location.' what's >>>>> the proper way to modify these values? >>>>> >>>>> i was translating some of the italian comments in rect_packer.cpp but >>>>> couldn't find translations for the following: >>>>> posiziono - position? >>>>> pe plus' >>>>> could someone please translate these to english for me? >>>>> >>>>> thanks >>>>> imran >>>>> >>>>> On Tue, Apr 29, 2008 at 11:48 PM, skunkwerk <sku...@gm...> >>>>> wrote: >>>>> >>>>>> thanks Paolo, >>>>>> i guess CMesh0 is how i'll get the faceiterator - i'm working on >>>>>> some collada importer optimizations right now but might get back to this in >>>>>> a few days. what options do we have for a numerical solver? >>>>>> >>>>>> imran >>>>>> >>>>>> On Tue, Apr 29, 2008 at 2:22 PM, Paolo Cignoni < >>>>>> pao...@is...> wrote: >>>>>> >>>>>>> I like your proposal, but I strongly suggest you to proceed gradually >>>>>>> and start and complete and test a functionality at a time. >>>>>>> >>>>>>> First of all start to just add a simple rectangular packer, >>>>>>> >>>>>>> - then try to use the rect_packer provided code >>>>>>> >>>>>>> - then try to look at the code in the >>>>>>> trimesh/textcoord_optimization.h file. >>>>>>> >>>>>>> Before facing LSCM we should solve the issue of what numerical solver >>>>>>> use for it and for other issues that we have around in the vcg. >>>>>>> I hope we could take some decision in the next weeks about the >>>>>>> numeric solver in the vcg. >>>>>>> >>>>>>> I noticed that some notes on the basic types were missing so i added >>>>>>> it in http://meshlab.sourceforge.net/wiki/index.php/Writing_a_Plugin >>>>>>> Feel also free to contribute to the wiki in the part about the >>>>>>> writing of the plugins when you see points needing some clarification or a >>>>>>> deeper discussion. >>>>>>> >>>>>>> >>>>>>> cheers >>>>>>> p. >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> skunkwerk wrote: >>>>>>> >>>>>>> thanks for the hints paolo, >>>>>>> i wanted to use this algorithm: >>>>>>> http://alice.loria.fr/php/article.php?pub=../publications/papers/2002/lscm >>>>>>> but it seemed like it needed information on the actual models, and >>>>>>> was taking in arbitrarily-shaped textures. >>>>>>> >>>>>>> the only other algorithm i've found for texture packing is a >>>>>>> recursive tree-based one: >>>>>>> http://www.blackpawn.com/texts/lightmaps/default.html >>>>>>> >>>>>>> i tried this line (along with everything else i could think of): >>>>>>> MeshModel::FaceIterator fit; >>>>>>> but it didn't like the 'MeshModel' part - is 'mm' not an object of >>>>>>> type MeshModel? >>>>>>> >>>>>>> if someone could suggest the correct syntax i can get started on >>>>>>> testing the texture atlas >>>>>>> >>>>>>> thanks, >>>>>>> imran >>>>>>> >>>>>>> On Tue, Apr 29, 2008 at 2:13 AM, Paolo Cignoni < >>>>>>> pao...@is...> wrote: >>>>>>> >>>>>>> skunkwerk wrote: >>>>>>> > i've attached a texture atlas function. >>>>>>> > >>>>>>> > it compiles except for a ConstFaceIterator error - I've tried using >>>>>>> > the template<typename MESHTYPE> but that didn't work either. the >>>>>>> > algorithm is VERY basic (textures are added one after another in a >>>>>>> > row), but should work. i couldn't find any algorithms for more >>>>>>> > closely-packed positioning, but i could look at the code in >>>>>>> > openscenegraph's texture atlas generator. >>>>>>> Nice Job! >>>>>>> >>>>>>> The right place for this stuff is the filter_texture plugin that i >>>>>>> have >>>>>>> just added, >>>>>>> Now it is just a placeholder filter you should add your code there. >>>>>>> >>>>>>> Important: >>>>>>> In the plugin dir you can find a rect_packer that should make good >>>>>>> job. >>>>>>> please use it to build a good packing of the texture size >>>>>>> >>>>>>> > questions: >>>>>>> > 1) if someone could tell me how to iterate through faces from a >>>>>>> > function outside vcg, that'd be great so i could test this out >>>>>>> We have started to improve the developer documentation: two new >>>>>>> pages in >>>>>>> the wiki should help you >>>>>>> >>>>>>> http://meshlab.sourceforge.net/wiki/index.php/Accessing_the_mesh >>>>>>> http://meshlab.sourceforge.net/wiki/index.php/Algorithms >>>>>>> >>>>>>> > 2) paolo, what's the best location of this function? i'm >>>>>>> currently >>>>>>> > putting it in mainwindow_Runtime.cpp to test it out >>>>>>> The right location is inside the filter_texture plugin >>>>>>> possible parameter of the plugin: >>>>>>> - format of the saved texture (as a enum) >>>>>>> - max size of the texture >>>>>>> >>>>>>> > 3) how do I access the data from already-loaded textures? so i >>>>>>> can >>>>>>> > prevent having to load all the textures again... >>>>>>> Do not worry about that. Feel free to use QT to load again the >>>>>>> images >>>>>>> and process them, it should not create a significant overhead. >>>>>>> >>>>>>> Once your processing is ended (and you have saved the new texture) >>>>>>> you >>>>>>> should update the texture names stored inside the mesh sending a >>>>>>> signal >>>>>>> to the updateTexture() slot of the mainwindow (the parent of the >>>>>>> action) >>>>>>> >>>>>>> cheers >>>>>>> p. >>>>>>> >>>>>>> -- >>>>>>> Paolo Cignoni -- Senior Researcher >>>>>>> Visual Computing Laboratory - ISTI - CNR >>>>>>> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>>>> >>>>>>> ISTI - CNR >>>>>>> Via Moruzzi 1, >>>>>>> 56124 Pisa >>>>>>> ITALY >>>>>>> >>>>>>> >>>>>>> >>>>>>> ------------------------------------------------------------------------- >>>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>>> Don't miss this year's exciting event. There's still time to save >>>>>>> $100. >>>>>>> Use priority code J8TL2D2. >>>>>>> >>>>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>>> _______________________________________________ >>>>>>> Meshlab-devel mailing list >>>>>>> Mes...@li... >>>>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>>> >>>>>>> >>>>>>> ------------------------------ >>>>>>> >>>>>>> ------------------------------------------------------------------------- >>>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>>> >>>>>>> ------------------------------ >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> Paolo Cignoni -- Senior Researcher >>>>>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>>>> >>>>>>> ISTI - CNR >>>>>>> Via Moruzzi 1, >>>>>>> 56124 Pisa >>>>>>> ITALY >>>>>>> >>>>>>> >>>>>>> >>>>>>> ------------------------------------------------------------------------- >>>>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>>>> Don't miss this year's exciting event. There's still time to save >>>>>>> $100. >>>>>>> Use priority code J8TL2D2. >>>>>>> >>>>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>>>> _______________________________________________ >>>>>>> Meshlab-devel mailing list >>>>>>> Mes...@li... >>>>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>>>> >>>>>>> >>>>>> >>>>> ------------------------------ >>>>> >>>>> ------------------------------------------------------------------------- >>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>> >>>>> ------------------------------ >>>>> >>>>> _______________________________________________ >>>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>> >>>>> >>>>> >>>>> -- >>>>> Paolo Cignoni -- Senior Researcher >>>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>>> >>>>> ISTI - CNR >>>>> Via Moruzzi 1, >>>>> 56124 Pisa >>>>> ITALY >>>>> >>>>> >>>>> >>>>> ------------------------------------------------------------------------- >>>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>>> Don't miss this year's exciting event. There's still time to save $100. >>>>> Use priority code J8TL2D2. >>>>> >>>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>>> _______________________________________________ >>>>> Meshlab-devel mailing list >>>>> Mes...@li... >>>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>>> >>>>> >>>> ------------------------------ >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> >>>> ------------------------------ >>>> >>>> _______________________________________________ >>>> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>>> >>>> -- >>>> Paolo Cignoni -- Senior Researcher >>>> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >>>> >>>> ISTI - CNR >>>> Via Moruzzi 1, >>>> 56124 Pisa >>>> ITALY >>>> >>>> >>>> >>>> ------------------------------------------------------------------------- >>>> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >>>> Don't miss this year's exciting event. There's still time to save $100. >>>> Use priority code J8TL2D2. >>>> >>>> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >>>> _______________________________________________ >>>> Meshlab-devel mailing list >>>> Mes...@li... >>>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>>> >>>> >>> >> ------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> >> ------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save $100. >> Use priority code J8TL2D2. >> >> http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> > |
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From: Paolo C. <pao...@is...> - 2008-05-19 07:03:35
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skunkwerk wrote: > thanks Paolo, > sorry - i should have caught that. I'm testing out the code right > now, and I need confirmation of UV coordinate formats: > > 1) if the coordinates are >1 that means the textures are to be > repeated/tiled, correct? but meshlab can handle this, I don't need to > change anything. > 2) what do negative uv coordinates mean? I assumed the origin (0,0) > was at the top-left corner of the textures. I don't see how you could > have negative uv coordinates (as i'm seeing in some models) unless the > origin is in the center. > > cheers, > imran > yes texture coords out of the [0..1] range mean that the mesh is using tiling and assuming that the texture is tiled. Tiling works also in the negative space. Note that when a mesh is using tiling the atalsing procedure it is not very simple. a simple clamping the the coords does not work verywell and can produce weird results. For example a triangle spanning from 0.9 to 1.1. cannot be replaced with a triangle spanning from 0.9 to 0.1, instead of simply crossing the border thenewe traiangle crosses the whole texture. In this case the only correct solution, i fear, is to split the triangle in two along the 1.0 tex coord value, so that we have two trianbgles, a first one spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. - as a first option do a modulo and simply issue a warning. - as a second option we should clip the mesh. It can be done by using the refineE and using a edge predicate that splits the edge only if its textture coords are not inside the 0.1 range. Multiple passes could be required (separately for each texture coord axis) cheers p. -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-05-19 19:01:21
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thanks Paolo, page 10 of the paper here: ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf discusses this issue, and says you can either use pixel shaders (which might be possible in meshlab, but not generic viewers) or just repeat the texture however many times necessary in the atlas itself (wrap or mirror modes) - i did a quick test in photoshop with a single and tiled texture to see if it would be able to detect the tiling and not increase the file size - however the original file was 240k, and the tiled file ended up being 342k when using PNG. the other option might be to simply resize the tiled textures to fit into the size occupied by the original texture - but you would decrease the resolution by doing so. but the 3d viewer at the default zoom would already display a lower-resolution version of the texture if it must be repeated within a fixed area, right? so the issue would only be visible at higher zoom levels - when you might expect the resolution of a tiled texture to increase, but doesn't. perhaps we could have a user-selectable value that determines how we tradeoff texture atlas size and tiled texture resolution? graci, imran On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni <pao...@is...> wrote: > skunkwerk wrote: > > thanks Paolo, > > sorry - i should have caught that. I'm testing out the code right > > now, and I need confirmation of UV coordinate formats: > > > > 1) if the coordinates are >1 that means the textures are to be > > repeated/tiled, correct? but meshlab can handle this, I don't need to > > change anything. > > 2) what do negative uv coordinates mean? I assumed the origin (0,0) > > was at the top-left corner of the textures. I don't see how you could > > have negative uv coordinates (as i'm seeing in some models) unless the > > origin is in the center. > > > > cheers, > > imran > > > yes texture coords out of the [0..1] range mean that the mesh is using > tiling and assuming that the texture is tiled. Tiling works also in the > negative space. > > Note that when a mesh is using tiling the atalsing procedure it is not > very simple. > a simple clamping the the coords does not work verywell and can produce > weird results. > > For example a triangle spanning from 0.9 to 1.1. cannot be replaced with > a triangle spanning from 0.9 to 0.1, instead of simply crossing the > border thenewe traiangle crosses the whole texture. In this case the > only correct solution, i fear, is to split the triangle in two along the > 1.0 tex coord value, so that we have two trianbgles, a first one > spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. > > - as a first option do a modulo and simply issue a warning. > - as a second option we should clip the mesh. It can be done by using > the refineE and using a edge predicate that splits the edge only if its > textture coords are not inside the 0.1 range. Multiple passes could be > required (separately for each texture coord axis) > > cheers > p. > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > |
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From: Paolo C. <pao...@is...> - 2008-05-19 21:05:43
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I would like to avoid the use of shaders, it seems to me a too not general solution. Far from the mesh processing spirit of MeshLab. There are two solutions 1) repeating. surely works, but increase the size of the final texture. 2) clipping the triangles. a bit harder. as a negative side it changes the topology of the mesh, increasing its complexity in terms of number of triangles and vertices. Luckyly enough the vcg library offers methods for this kind of clipping that make it in a almost automatic way. Look at the refine classes. Imho both of the two solution are viable. The best things could be to offer both options to the user and let him choose :) I would not consider resampling here. it is somethng that you can always perform (and probably in a better way) outside meshlab with any image tool, without touching at all the mesh. Do not concentrate too much on the size of the compressed textures. I do not think that it is the most important issue here. Cheers and thanks for your help p. skunkwerk wrote: > thanks Paolo, > page 10 of the paper here: > ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf > discusses this issue, and says you can either use pixel shaders (which > might be possible in meshlab, but not generic viewers) or just repeat > the texture however many times necessary in the atlas itself (wrap or > mirror modes) - i did a quick test in photoshop with a single and > tiled texture to see if it would be able to detect the tiling and not > increase the file size - however the original file was 240k, and the > tiled file ended up being 342k when using PNG. the other option might > be to simply resize the tiled textures to fit into the size occupied > by the original texture - but you would decrease the resolution by > doing so. but the 3d viewer at the default zoom would already display > a lower-resolution version of the texture if it must be repeated > within a fixed area, right? so the issue would only be visible at > higher zoom levels - when you might expect the resolution of a tiled > texture to increase, but doesn't. perhaps we could have a > user-selectable value that determines how we tradeoff texture atlas > size and tiled texture resolution? > > graci, > imran > > On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > skunkwerk wrote: > > thanks Paolo, > > sorry - i should have caught that. I'm testing out the code > right > > now, and I need confirmation of UV coordinate formats: > > > > 1) if the coordinates are >1 that means the textures are to be > > repeated/tiled, correct? but meshlab can handle this, I don't > need to > > change anything. > > 2) what do negative uv coordinates mean? I assumed the origin > (0,0) > > was at the top-left corner of the textures. I don't see how you > could > > have negative uv coordinates (as i'm seeing in some models) > unless the > > origin is in the center. > > > > cheers, > > imran > > > yes texture coords out of the [0..1] range mean that the mesh is using > tiling and assuming that the texture is tiled. Tiling works also > in the > negative space. > > Note that when a mesh is using tiling the atalsing procedure it is not > very simple. > a simple clamping the the coords does not work verywell and can > produce > weird results. > > For example a triangle spanning from 0.9 to 1.1. cannot be > replaced with > a triangle spanning from 0.9 to 0.1, instead of simply crossing the > border thenewe traiangle crosses the whole texture. In this case the > only correct solution, i fear, is to split the triangle in two > along the > 1.0 tex coord value, so that we have two trianbgles, a first one > spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. > > - as a first option do a modulo and simply issue a warning. > - as a second option we should clip the mesh. It can be done by using > the refineE and using a edge predicate that splits the edge only > if its > textture coords are not inside the 0.1 range. Multiple passes could be > required (separately for each texture coord axis) > > cheers > p. > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-05-20 21:23:16
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thanks Paolo, i'm working on supporting tiling textures right now for the atlas. i was looking at some 3d models - i have UVs in some of them that are 67,-43. That would mean I would have to repeat that texture 67 times in the x direction, and 43 times in the y, correct? Do I have to find the maximum U & V coordinate of each textures' faces, and scale by that factor? what if a different face is using the same texture, but not tiled? are there any resources on the web for how to do this correctly? regards, imran On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni <pao...@is...> wrote: > I would like to avoid the use of shaders, it seems to me a too not general > solution. Far from the mesh processing spirit of MeshLab. > > There are two solutions > 1) repeating. surely works, but increase the size of the final texture. > 2) clipping the triangles. a bit harder. as a negative side it changes the > topology of the mesh, increasing its complexity in terms of number of > triangles and vertices. Luckyly enough the vcg library offers methods for > this kind of clipping that make it in a almost automatic way. Look at the > refine classes. > > Imho both of the two solution are viable. The best things could be to offer > both options to the user and let him choose :) > > I would not consider resampling here. it is somethng that you can always > perform (and probably in a better way) outside meshlab with any image tool, > without touching at all the mesh. > > Do not concentrate too much on the size of the compressed textures. I do > not think that it is the most important issue here. > > Cheers and thanks for your help > p. > > > > skunkwerk wrote: > > thanks Paolo, > page 10 of the paper here: > ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf > discusses this issue, and says you can either use pixel shaders (which > might be possible in meshlab, but not generic viewers) or just repeat the > texture however many times necessary in the atlas itself (wrap or mirror > modes) - i did a quick test in photoshop with a single and tiled texture to > see if it would be able to detect the tiling and not increase the file size > - however the original file was 240k, and the tiled file ended up being 342k > when using PNG. the other option might be to simply resize the tiled > textures to fit into the size occupied by the original texture - but you > would decrease the resolution by doing so. but the 3d viewer at the default > zoom would already display a lower-resolution version of the texture if it > must be repeated within a fixed area, right? so the issue would only be > visible at higher zoom levels - when you might expect the resolution of a > tiled texture to increase, but doesn't. perhaps we could have a > user-selectable value that determines how we tradeoff texture atlas size and > tiled texture resolution? > > graci, > imran > > On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni <pao...@is...> > wrote: > > skunkwerk wrote: > > thanks Paolo, > > sorry - i should have caught that. I'm testing out the code right > > now, and I need confirmation of UV coordinate formats: > > > > 1) if the coordinates are >1 that means the textures are to be > > repeated/tiled, correct? but meshlab can handle this, I don't need to > > change anything. > > 2) what do negative uv coordinates mean? I assumed the origin (0,0) > > was at the top-left corner of the textures. I don't see how you could > > have negative uv coordinates (as i'm seeing in some models) unless the > > origin is in the center. > > > > cheers, > > imran > > > yes texture coords out of the [0..1] range mean that the mesh is using > tiling and assuming that the texture is tiled. Tiling works also in the > negative space. > > Note that when a mesh is using tiling the atalsing procedure it is not > very simple. > a simple clamping the the coords does not work verywell and can produce > weird results. > > For example a triangle spanning from 0.9 to 1.1. cannot be replaced with > a triangle spanning from 0.9 to 0.1, instead of simply crossing the > border thenewe traiangle crosses the whole texture. In this case the > only correct solution, i fear, is to split the triangle in two along the > 1.0 tex coord value, so that we have two trianbgles, a first one > spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. > > - as a first option do a modulo and simply issue a warning. > - as a second option we should clip the mesh. It can be done by using > the refineE and using a edge predicate that splits the edge only if its > textture coords are not inside the 0.1 range. Multiple passes could be > required (separately for each texture coord axis) > > cheers > p. > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
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From: Paolo C. <pao...@is...> - 2008-05-20 23:09:30
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I think that with a bit of care you can safely apply a same modulo operation to the tex coords of the vertex of a same face so that you can relocate it as close as possible to the origin of the uv coord system Explaining better. consider a model of a wall, tessllated (100x100 vertexes arranged in a regular grid), this wall is textured with a brick texture that is tiled 30 times along u and 40 times along v. There is no need to repeat 30x40 times the original texture simply because each triangle will not span over many copies of the original texture but in the worst case at most two. So in this particular case the needed texture size will be only 2x2 times In other words you have to look at the maximum span of each triangle, not the absolute maximum/minimum. I have not seen good documents on the web explaining all the gory details of this process. Keep this sturff them documented in the wiki :) Cheers p. skunkwerk wrote: > thanks Paolo, > i'm working on supporting tiling textures right now for the atlas. > > i was looking at some 3d models - i have UVs in some of them that are > 67,-43. That would mean I would have to repeat that texture 67 times > in the x direction, and 43 times in the y, correct? Do I have to find > the maximum U & V coordinate of each textures' faces, and scale by > that factor? what if a different face is using the same texture, but > not tiled? are there any resources on the web for how to do this > correctly? > > regards, > imran > > On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > I would like to avoid the use of shaders, it seems to me a too not > general solution. Far from the mesh processing spirit of MeshLab. > > There are two solutions > 1) repeating. surely works, but increase the size of the final > texture. > 2) clipping the triangles. a bit harder. as a negative side it > changes the topology of the mesh, increasing its complexity in > terms of number of triangles and vertices. Luckyly enough the vcg > library offers methods for this kind of clipping that make it in > a almost automatic way. Look at the refine classes. > > Imho both of the two solution are viable. The best things could be > to offer both options to the user and let him choose :) > > I would not consider resampling here. it is somethng that you can > always perform (and probably in a better way) outside meshlab with > any image tool, without touching at all the mesh. > > Do not concentrate too much on the size of the compressed > textures. I do not think that it is the most important issue here. > > Cheers and thanks for your help > p. > > > > skunkwerk wrote: >> thanks Paolo, >> page 10 of the paper here: >> ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf >> discusses this issue, and says you can either use pixel shaders >> (which might be possible in meshlab, but not generic viewers) or >> just repeat the texture however many times necessary in the atlas >> itself (wrap or mirror modes) - i did a quick test in photoshop >> with a single and tiled texture to see if it would be able to >> detect the tiling and not increase the file size - however the >> original file was 240k, and the tiled file ended up being 342k >> when using PNG. the other option might be to simply resize the >> tiled textures to fit into the size occupied by the original >> texture - but you would decrease the resolution by doing so. but >> the 3d viewer at the default zoom would already display a >> lower-resolution version of the texture if it must be repeated >> within a fixed area, right? so the issue would only be visible >> at higher zoom levels - when you might expect the resolution of a >> tiled texture to increase, but doesn't. perhaps we could have a >> user-selectable value that determines how we tradeoff texture >> atlas size and tiled texture resolution? >> >> graci, >> imran >> >> On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni >> <pao...@is... <mailto:pao...@is...>> wrote: >> >> skunkwerk wrote: >> > thanks Paolo, >> > sorry - i should have caught that. I'm testing out the >> code right >> > now, and I need confirmation of UV coordinate formats: >> > >> > 1) if the coordinates are >1 that means the textures are to be >> > repeated/tiled, correct? but meshlab can handle this, I >> don't need to >> > change anything. >> > 2) what do negative uv coordinates mean? I assumed the >> origin (0,0) >> > was at the top-left corner of the textures. I don't see >> how you could >> > have negative uv coordinates (as i'm seeing in some models) >> unless the >> > origin is in the center. >> > >> > cheers, >> > imran >> > >> yes texture coords out of the [0..1] range mean that the mesh >> is using >> tiling and assuming that the texture is tiled. Tiling works >> also in the >> negative space. >> >> Note that when a mesh is using tiling the atalsing procedure >> it is not >> very simple. >> a simple clamping the the coords does not work verywell and >> can produce >> weird results. >> >> For example a triangle spanning from 0.9 to 1.1. cannot be >> replaced with >> a triangle spanning from 0.9 to 0.1, instead of simply >> crossing the >> border thenewe traiangle crosses the whole texture. In this >> case the >> only correct solution, i fear, is to split the triangle in >> two along the >> 1.0 tex coord value, so that we have two trianbgles, a first one >> spanning from 0.9 to 1.0 and a second one spanning from 0.0 >> to 0.1. >> >> - as a first option do a modulo and simply issue a warning. >> - as a second option we should clip the mesh. It can be done >> by using >> the refineE and using a edge predicate that splits the edge >> only if its >> textture coords are not inside the 0.1 range. Multiple passes >> could be >> required (separately for each texture coord axis) >> >> cheers >> p. >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni >> <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft Defy all challenges. >> Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni > <http://vcg.isti.cnr.it/%7Ecignoni> ISTI - CNR Via Moruzzi 1, > 56124 Pisa ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
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From: skunkwerk <sku...@gm...> - 2008-05-21 01:33:32
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thanks Paolo, I think I know what you mean, but is that the worst-case? In the drawing I made here: www.akbars.net/texcoords.png assume each square is composed of two triangles (denoted by the red line). The first square shows the normal 0-1 texcoords, no problem. the second square shows what I think it would look like when the texture is repeated twice along both axes, and likewise for the last square. The reason I was thinking about finding the maximum UV coordinates was that I could then generate that many copies (so the texture looks like the last square) and then for faces that have UVs < 4 (in this case), i'd divide by the maximum UVs. So for the second square 2,0 would correspond to 2/4=1/2, 0. by the span of each triangle, i assume you mean the difference between the maximum & mininum of the vertexes UV coordinates? with my example, both our approaches would be the same I think as the last square's triangle starts at 0 and goes to 4 at the bottom. but that obviously wouldn't always be the case. so to finalize, what you are suggesting is: 1) generate an array of Point2f that will store the maximum difference in the u & v coordinates for each texture index 2) iterate through all faces, and for each face do 6 subtractions to figure out the maximum difference for the U & V coordinates of vertexes in that face 3) if the value computed in 2) is greater than the value stored in the array from 1), assign that value to the array 4) when done, copy the texture the necessary number of times (as indicated in the array), with values rounded up to the nearest integer 5) iterate through faces and adjust UV coordinates by the new dimensions of each texture imran On Tue, May 20, 2008 at 4:08 PM, Paolo Cignoni <pao...@is...> wrote: > I think that with a bit of care you can safely apply a same modulo > operation to the tex coords of the vertex of a same face so that you can > relocate it as close as possible to the origin of the uv coord system > > Explaining better. consider a model of a wall, tessllated (100x100 vertexes > arranged in a regular grid), this wall is textured with a brick texture that > is tiled 30 times along u and 40 times along v. There is no need to repeat > 30x40 times the original texture simply because each triangle will not span > over many copies of the original texture but in the worst case at most two. > So in this particular case the needed texture size will be only 2x2 times > In other words you have to look at the maximum span of each triangle, not > the absolute maximum/minimum. > > I have not seen good documents on the web explaining all the gory details > of this process. Keep this sturff them documented in the wiki :) > > Cheers > > p. > > > skunkwerk wrote: > > thanks Paolo, > i'm working on supporting tiling textures right now for the atlas. > > i was looking at some 3d models - i have UVs in some of them that are > 67,-43. That would mean I would have to repeat that texture 67 times in the > x direction, and 43 times in the y, correct? Do I have to find the maximum > U & V coordinate of each textures' faces, and scale by that factor? what if > a different face is using the same texture, but not tiled? are there any > resources on the web for how to do this correctly? > > regards, > imran > > On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni <pao...@is...> > wrote: > > I would like to avoid the use of shaders, it seems to me a too not general > solution. Far from the mesh processing spirit of MeshLab. > > There are two solutions > 1) repeating. surely works, but increase the size of the final texture. > 2) clipping the triangles. a bit harder. as a negative side it changes the > topology of the mesh, increasing its complexity in terms of number of > triangles and vertices. Luckyly enough the vcg library offers methods for > this kind of clipping that make it in a almost automatic way. Look at the > refine classes. > > Imho both of the two solution are viable. The best things could be to offer > both options to the user and let him choose :) > > I would not consider resampling here. it is somethng that you can always > perform (and probably in a better way) outside meshlab with any image tool, > without touching at all the mesh. > > Do not concentrate too much on the size of the compressed textures. I do > not think that it is the most important issue here. > > Cheers and thanks for your help > p. > > > > skunkwerk wrote: > > thanks Paolo, > page 10 of the paper here: > ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf > discusses this issue, and says you can either use pixel shaders (which > might be possible in meshlab, but not generic viewers) or just repeat the > texture however many times necessary in the atlas itself (wrap or mirror > modes) - i did a quick test in photoshop with a single and tiled texture to > see if it would be able to detect the tiling and not increase the file size > - however the original file was 240k, and the tiled file ended up being 342k > when using PNG. the other option might be to simply resize the tiled > textures to fit into the size occupied by the original texture - but you > would decrease the resolution by doing so. but the 3d viewer at the default > zoom would already display a lower-resolution version of the texture if it > must be repeated within a fixed area, right? so the issue would only be > visible at higher zoom levels - when you might expect the resolution of a > tiled texture to increase, but doesn't. perhaps we could have a > user-selectable value that determines how we tradeoff texture atlas size and > tiled texture resolution? > > graci, > imran > > On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni <pao...@is...> > wrote: > > skunkwerk wrote: > > thanks Paolo, > > sorry - i should have caught that. I'm testing out the code right > > now, and I need confirmation of UV coordinate formats: > > > > 1) if the coordinates are >1 that means the textures are to be > > repeated/tiled, correct? but meshlab can handle this, I don't need to > > change anything. > > 2) what do negative uv coordinates mean? I assumed the origin (0,0) > > was at the top-left corner of the textures. I don't see how you could > > have negative uv coordinates (as i'm seeing in some models) unless the > > origin is in the center. > > > > cheers, > > imran > > > yes texture coords out of the [0..1] range mean that the mesh is using > tiling and assuming that the texture is tiled. Tiling works also in the > negative space. > > Note that when a mesh is using tiling the atalsing procedure it is not > very simple. > a simple clamping the the coords does not work verywell and can produce > weird results. > > For example a triangle spanning from 0.9 to 1.1. cannot be replaced with > a triangle spanning from 0.9 to 0.1, instead of simply crossing the > border thenewe traiangle crosses the whole texture. In this case the > only correct solution, i fear, is to split the triangle in two along the > 1.0 tex coord value, so that we have two trianbgles, a first one > spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. > > - as a first option do a modulo and simply issue a warning. > - as a second option we should clip the mesh. It can be done by using > the refineE and using a edge predicate that splits the edge only if its > textture coords are not inside the 0.1 range. Multiple passes could be > required (separately for each texture coord axis) > > cheers > p. > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
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From: skunkwerk <sku...@gm...> - 2008-05-21 06:18:21
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hi folks, i committed an updated version of the filter texture atlas builder that should handle tiled textures, if my algorithm is correct. it compiles, it doesn't crash, but the results don't seem to be correct. could someone take a look at the code/saved file/atlas and suggest possible problems? i don't know if i'm handling negative uv coordinates correctly. imran On Tue, May 20, 2008 at 6:33 PM, skunkwerk <sku...@gm...> wrote: > thanks Paolo, > I think I know what you mean, but is that the worst-case? In the > drawing I made here: > www.akbars.net/texcoords.png > assume each square is composed of two triangles (denoted by the red line). > The first square shows the normal 0-1 texcoords, no problem. the second > square shows what I think it would look like when the texture is repeated > twice along both axes, and likewise for the last square. The reason I was > thinking about finding the maximum UV coordinates was that I could then > generate that many copies (so the texture looks like the last square) and > then for faces that have UVs < 4 (in this case), i'd divide by the maximum > UVs. So for the second square 2,0 would correspond to 2/4=1/2, 0. > > by the span of each triangle, i assume you mean the difference between the > maximum & mininum of the vertexes UV coordinates? with my example, both our > approaches would be the same I think as the last square's triangle starts at > 0 and goes to 4 at the bottom. but that obviously wouldn't always be the > case. so to finalize, what you are suggesting is: > > 1) generate an array of Point2f that will store the maximum difference in > the u & v coordinates for each texture index > 2) iterate through all faces, and for each face do 6 subtractions to > figure out the maximum difference for the U & V coordinates of vertexes in > that face > 3) if the value computed in 2) is greater than the value stored in the > array from 1), assign that value to the array > 4) when done, copy the texture the necessary number of times (as indicated > in the array), with values rounded up to the nearest integer > 5) iterate through faces and adjust UV coordinates by the new dimensions > of each texture > > imran > > > On Tue, May 20, 2008 at 4:08 PM, Paolo Cignoni <pao...@is...> > wrote: > >> I think that with a bit of care you can safely apply a same modulo >> operation to the tex coords of the vertex of a same face so that you can >> relocate it as close as possible to the origin of the uv coord system >> >> Explaining better. consider a model of a wall, tessllated (100x100 >> vertexes arranged in a regular grid), this wall is textured with a brick >> texture that is tiled 30 times along u and 40 times along v. There is no >> need to repeat 30x40 times the original texture simply because each triangle >> will not span over many copies of the original texture but in the worst case >> at most two. So in this particular case the needed texture size will be only >> 2x2 times >> In other words you have to look at the maximum span of each triangle, not >> the absolute maximum/minimum. >> >> I have not seen good documents on the web explaining all the gory details >> of this process. Keep this sturff them documented in the wiki :) >> >> Cheers >> >> p. >> >> >> skunkwerk wrote: >> >> thanks Paolo, >> i'm working on supporting tiling textures right now for the atlas. >> >> i was looking at some 3d models - i have UVs in some of them that are >> 67,-43. That would mean I would have to repeat that texture 67 times in the >> x direction, and 43 times in the y, correct? Do I have to find the maximum >> U & V coordinate of each textures' faces, and scale by that factor? what if >> a different face is using the same texture, but not tiled? are there any >> resources on the web for how to do this correctly? >> >> regards, >> imran >> >> On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni <pao...@is...> >> wrote: >> >> I would like to avoid the use of shaders, it seems to me a too not general >> solution. Far from the mesh processing spirit of MeshLab. >> >> There are two solutions >> 1) repeating. surely works, but increase the size of the final texture. >> 2) clipping the triangles. a bit harder. as a negative side it changes the >> topology of the mesh, increasing its complexity in terms of number of >> triangles and vertices. Luckyly enough the vcg library offers methods for >> this kind of clipping that make it in a almost automatic way. Look at the >> refine classes. >> >> Imho both of the two solution are viable. The best things could be to >> offer both options to the user and let him choose :) >> >> I would not consider resampling here. it is somethng that you can always >> perform (and probably in a better way) outside meshlab with any image tool, >> without touching at all the mesh. >> >> Do not concentrate too much on the size of the compressed textures. I do >> not think that it is the most important issue here. >> >> Cheers and thanks for your help >> p. >> >> >> >> skunkwerk wrote: >> >> thanks Paolo, >> page 10 of the paper here: >> ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf >> discusses this issue, and says you can either use pixel shaders (which >> might be possible in meshlab, but not generic viewers) or just repeat the >> texture however many times necessary in the atlas itself (wrap or mirror >> modes) - i did a quick test in photoshop with a single and tiled texture to >> see if it would be able to detect the tiling and not increase the file size >> - however the original file was 240k, and the tiled file ended up being 342k >> when using PNG. the other option might be to simply resize the tiled >> textures to fit into the size occupied by the original texture - but you >> would decrease the resolution by doing so. but the 3d viewer at the default >> zoom would already display a lower-resolution version of the texture if it >> must be repeated within a fixed area, right? so the issue would only be >> visible at higher zoom levels - when you might expect the resolution of a >> tiled texture to increase, but doesn't. perhaps we could have a >> user-selectable value that determines how we tradeoff texture atlas size and >> tiled texture resolution? >> >> graci, >> imran >> >> On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni < >> pao...@is...> wrote: >> >> skunkwerk wrote: >> > thanks Paolo, >> > sorry - i should have caught that. I'm testing out the code right >> > now, and I need confirmation of UV coordinate formats: >> > >> > 1) if the coordinates are >1 that means the textures are to be >> > repeated/tiled, correct? but meshlab can handle this, I don't need to >> > change anything. >> > 2) what do negative uv coordinates mean? I assumed the origin (0,0) >> > was at the top-left corner of the textures. I don't see how you could >> > have negative uv coordinates (as i'm seeing in some models) unless the >> > origin is in the center. >> > >> > cheers, >> > imran >> > >> yes texture coords out of the [0..1] range mean that the mesh is using >> tiling and assuming that the texture is tiled. Tiling works also in the >> negative space. >> >> Note that when a mesh is using tiling the atalsing procedure it is not >> very simple. >> a simple clamping the the coords does not work verywell and can produce >> weird results. >> >> For example a triangle spanning from 0.9 to 1.1. cannot be replaced with >> a triangle spanning from 0.9 to 0.1, instead of simply crossing the >> border thenewe traiangle crosses the whole texture. In this case the >> only correct solution, i fear, is to split the triangle in two along the >> 1.0 tex coord value, so that we have two trianbgles, a first one >> spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. >> >> - as a first option do a modulo and simply issue a warning. >> - as a second option we should clip the mesh. It can be done by using >> the refineE and using a edge predicate that splits the edge only if its >> textture coords are not inside the 0.1 range. Multiple passes could be >> required (separately for each texture coord axis) >> >> cheers >> p. >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> >> _______________________________________________ >> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> ------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> ------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> > |
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From: Paolo C. <pao...@is...> - 2008-05-21 06:52:06
|
Yes, it is not the worst case, but it is something that can happen. I think that you just need to compute the max span, relocate each triangle as close as possible to the origin and then repeat the texture as needed, Obviously the approach 2): clipping the mesh along the integer values of the tex coords is always a good safe option. in your case it would have transformed the two triangle mesh in a grid of 5x5 vertices and 32 triangles arranges in a regular grid. You have to define the edge predicate that says what edges have to be splitten (the one with texcoords spanning more than 1 and the rule to find the position and interpolated values of the new vertices. Look at the refine.h file and to the midpoint and EdgeLen classes. P. skunkwerk wrote: > thanks Paolo, > I think I know what you mean, but is that the worst-case? In the > drawing I made here: > www.akbars.net/texcoords.png <http://www.akbars.net/texcoords.png> > assume each square is composed of two triangles (denoted by the red > line). The first square shows the normal 0-1 texcoords, no problem. > the second square shows what I think it would look like when the > texture is repeated twice along both axes, and likewise for the last > square. The reason I was thinking about finding the maximum UV > coordinates was that I could then generate that many copies (so the > texture looks like the last square) and then for faces that have UVs < > 4 (in this case), i'd divide by the maximum UVs. So for the second > square 2,0 would correspond to 2/4=1/2, 0. > > by the span of each triangle, i assume you mean the difference between > the maximum & mininum of the vertexes UV coordinates? with my > example, both our approaches would be the same I think as the last > square's triangle starts at 0 and goes to 4 at the bottom. but that > obviously wouldn't always be the case. so to finalize, what you are > suggesting is: > > 1) generate an array of Point2f that will store the maximum > difference in the u & v coordinates for each texture index > 2) iterate through all faces, and for each face do 6 subtractions to > figure out the maximum difference for the U & V coordinates of > vertexes in that face > 3) if the value computed in 2) is greater than the value stored in > the array from 1), assign that value to the array > 4) when done, copy the texture the necessary number of times (as > indicated in the array), with values rounded up to the nearest integer > 5) iterate through faces and adjust UV coordinates by the new > dimensions of each texture > > imran > > On Tue, May 20, 2008 at 4:08 PM, Paolo Cignoni > <pao...@is... <mailto:pao...@is...>> wrote: > > I think that with a bit of care you can safely apply a same modulo > operation to the tex coords of the vertex of a same face so that > you can relocate it as close as possible to the origin of the uv > coord system > > Explaining better. consider a model of a wall, tessllated (100x100 > vertexes arranged in a regular grid), this wall is textured with a > brick texture that is tiled 30 times along u and 40 times along > v. There is no need to repeat 30x40 times the original texture > simply because each triangle will not span over many copies of the > original texture but in the worst case at most two. So in this > particular case the needed texture size will be only 2x2 times > In other words you have to look at the maximum span of each > triangle, not the absolute maximum/minimum. > > I have not seen good documents on the web explaining all the gory > details of this process. Keep this sturff them documented in the > wiki :) > > Cheers > > p. > > > skunkwerk wrote: >> thanks Paolo, >> i'm working on supporting tiling textures right now for the atlas. >> >> i was looking at some 3d models - i have UVs in some of them that >> are 67,-43. That would mean I would have to repeat that texture >> 67 times in the x direction, and 43 times in the y, correct? Do >> I have to find the maximum U & V coordinate of each textures' >> faces, and scale by that factor? what if a different face is >> using the same texture, but not tiled? are there any resources >> on the web for how to do this correctly? >> >> regards, >> imran >> >> On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni >> <pao...@is... <mailto:pao...@is...>> wrote: >> >> I would like to avoid the use of shaders, it seems to me a >> too not general solution. Far from the mesh processing spirit >> of MeshLab. >> >> There are two solutions >> 1) repeating. surely works, but increase the size of the >> final texture. >> 2) clipping the triangles. a bit harder. as a negative side >> it changes the topology of the mesh, increasing its >> complexity in terms of number of triangles and vertices. >> Luckyly enough the vcg library offers methods for this kind >> of clipping that make it in a almost automatic way. Look at >> the refine classes. >> >> Imho both of the two solution are viable. The best things >> could be to offer both options to the user and let him choose :) >> >> I would not consider resampling here. it is somethng that you >> can always perform (and probably in a better way) outside >> meshlab with any image tool, without touching at all the mesh. >> >> Do not concentrate too much on the size of the compressed >> textures. I do not think that it is the most important issue >> here. >> >> Cheers and thanks for your help >> p. >> >> >> >> skunkwerk wrote: >>> thanks Paolo, >>> page 10 of the paper here: >>> ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf >>> discusses this issue, and says you can either use pixel >>> shaders (which might be possible in meshlab, but not generic >>> viewers) or just repeat the texture however many times >>> necessary in the atlas itself (wrap or mirror modes) - i did >>> a quick test in photoshop with a single and tiled texture to >>> see if it would be able to detect the tiling and not >>> increase the file size - however the original file was 240k, >>> and the tiled file ended up being 342k when using PNG. the >>> other option might be to simply resize the tiled textures to >>> fit into the size occupied by the original texture - but you >>> would decrease the resolution by doing so. but the 3d >>> viewer at the default zoom would already display a >>> lower-resolution version of the texture if it must be >>> repeated within a fixed area, right? so the issue would >>> only be visible at higher zoom levels - when you might >>> expect the resolution of a tiled texture to increase, but >>> doesn't. perhaps we could have a user-selectable value that >>> determines how we tradeoff texture atlas size and tiled >>> texture resolution? >>> >>> graci, >>> imran >>> >>> On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni >>> <pao...@is... >>> <mailto:pao...@is...>> wrote: >>> >>> skunkwerk wrote: >>> > thanks Paolo, >>> > sorry - i should have caught that. I'm testing out >>> the code right >>> > now, and I need confirmation of UV coordinate formats: >>> > >>> > 1) if the coordinates are >1 that means the textures >>> are to be >>> > repeated/tiled, correct? but meshlab can handle this, >>> I don't need to >>> > change anything. >>> > 2) what do negative uv coordinates mean? I assumed >>> the origin (0,0) >>> > was at the top-left corner of the textures. I don't >>> see how you could >>> > have negative uv coordinates (as i'm seeing in some >>> models) unless the >>> > origin is in the center. >>> > >>> > cheers, >>> > imran >>> > >>> yes texture coords out of the [0..1] range mean that the >>> mesh is using >>> tiling and assuming that the texture is tiled. Tiling >>> works also in the >>> negative space. >>> >>> Note that when a mesh is using tiling the atalsing >>> procedure it is not >>> very simple. >>> a simple clamping the the coords does not work verywell >>> and can produce >>> weird results. >>> >>> For example a triangle spanning from 0.9 to 1.1. cannot >>> be replaced with >>> a triangle spanning from 0.9 to 0.1, instead of simply >>> crossing the >>> border thenewe traiangle crosses the whole texture. In >>> this case the >>> only correct solution, i fear, is to split the triangle >>> in two along the >>> 1.0 tex coord value, so that we have two trianbgles, a >>> first one >>> spanning from 0.9 to 1.0 and a second one spanning from >>> 0.0 to 0.1. >>> >>> - as a first option do a modulo and simply issue a warning. >>> - as a second option we should clip the mesh. It can be >>> done by using >>> the refineE and using a edge predicate that splits the >>> edge only if its >>> textture coords are not inside the 0.1 range. Multiple >>> passes could be >>> required (separately for each texture coord axis) >>> >>> cheers >>> p. >>> >>> >>> >>> -- >>> Paolo Cignoni -- Senior Researcher >>> Visual Computing Laboratory - ISTI - CNR >>> http://vcg.isti.cnr.it/~cignoni >>> <http://vcg.isti.cnr.it/%7Ecignoni> >>> >>> ISTI - CNR >>> Via Moruzzi 1, >>> 56124 Pisa >>> ITALY >>> >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by: Microsoft >>> Defy all challenges. Microsoft(R) Visual Studio 2008. >>> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... >>> <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >>> >>> >>> ------------------------------------------------------------------------- >>> This SF.net email is sponsored by: Microsoft Defy all >>> challenges. Microsoft(R) Visual Studio 2008. >>> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >>> >>> _______________________________________________ >>> Meshlab-devel mailing list >>> Mes...@li... <mailto:Mes...@li...> >>> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >>> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni >> <http://vcg.isti.cnr.it/%7Ecignoni> ISTI - CNR Via Moruzzi 1, >> 56124 Pisa ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... <mailto:Mes...@li...> >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > <mailto:Mes...@li...> > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------------------------------------------------ > > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
|
From: skunkwerk <sku...@gm...> - 2008-05-21 15:00:42
|
thanks Paolo, i want to get the first approach working before I try the second one. 1) is the current way I'm computing the maximum span correct? 2) could you please explain what you mean by 'relocating each triangle as close as possible to the origin'? by origin, you mean the top-left corner of the texture? are you talking about moving the vertices of the triangle, or the UV coordinates? imran On Tue, May 20, 2008 at 10:17 PM, Paolo Cignoni <pao...@is...> wrote: > Yes, it is not the worst case, but it is something that can happen. > > I think that you just need to compute the max span, relocate each triangle > as close as possible to the origin and then repeat the texture as needed, > > Obviously the approach 2): clipping the mesh along the integer values of > the tex coords is always a good safe option. > in your case it would have transformed the two triangle mesh in a grid of > 5x5 vertices and 32 triangles arranges in a regular grid. > > You have to define the edge predicate that says what edges have to be > splitten (the one with texcoords spanning more than 1 > and the rule to find the position and interpolated values of the new > vertices. Look at the refine.h file and to the midpoint and EdgeLen classes. > > P. > > > > skunkwerk wrote: > > thanks Paolo, > I think I know what you mean, but is that the worst-case? In the > drawing I made here: > www.akbars.net/texcoords.png > assume each square is composed of two triangles (denoted by the red line). > The first square shows the normal 0-1 texcoords, no problem. the second > square shows what I think it would look like when the texture is repeated > twice along both axes, and likewise for the last square. The reason I was > thinking about finding the maximum UV coordinates was that I could then > generate that many copies (so the texture looks like the last square) and > then for faces that have UVs < 4 (in this case), i'd divide by the maximum > UVs. So for the second square 2,0 would correspond to 2/4=1/2, 0. > > by the span of each triangle, i assume you mean the difference between the > maximum & mininum of the vertexes UV coordinates? with my example, both our > approaches would be the same I think as the last square's triangle starts at > 0 and goes to 4 at the bottom. but that obviously wouldn't always be the > case. so to finalize, what you are suggesting is: > > 1) generate an array of Point2f that will store the maximum difference in > the u & v coordinates for each texture index > 2) iterate through all faces, and for each face do 6 subtractions to > figure out the maximum difference for the U & V coordinates of vertexes in > that face > 3) if the value computed in 2) is greater than the value stored in the > array from 1), assign that value to the array > 4) when done, copy the texture the necessary number of times (as indicated > in the array), with values rounded up to the nearest integer > 5) iterate through faces and adjust UV coordinates by the new dimensions > of each texture > > imran > > On Tue, May 20, 2008 at 4:08 PM, Paolo Cignoni <pao...@is...> > wrote: > > I think that with a bit of care you can safely apply a same modulo > operation to the tex coords of the vertex of a same face so that you can > relocate it as close as possible to the origin of the uv coord system > > Explaining better. consider a model of a wall, tessllated (100x100 vertexes > arranged in a regular grid), this wall is textured with a brick texture that > is tiled 30 times along u and 40 times along v. There is no need to repeat > 30x40 times the original texture simply because each triangle will not span > over many copies of the original texture but in the worst case at most two. > So in this particular case the needed texture size will be only 2x2 times > In other words you have to look at the maximum span of each triangle, not > the absolute maximum/minimum. > > I have not seen good documents on the web explaining all the gory details > of this process. Keep this sturff them documented in the wiki :) > > Cheers > p. > > > skunkwerk wrote: > > thanks Paolo, > i'm working on supporting tiling textures right now for the atlas. > > i was looking at some 3d models - i have UVs in some of them that are > 67,-43. That would mean I would have to repeat that texture 67 times in the > x direction, and 43 times in the y, correct? Do I have to find the maximum > U & V coordinate of each textures' faces, and scale by that factor? what if > a different face is using the same texture, but not tiled? are there any > resources on the web for how to do this correctly? > > regards, > imran > > On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni <pao...@is...> > wrote: > > I would like to avoid the use of shaders, it seems to me a too not general > solution. Far from the mesh processing spirit of MeshLab. > > There are two solutions > 1) repeating. surely works, but increase the size of the final texture. > 2) clipping the triangles. a bit harder. as a negative side it changes the > topology of the mesh, increasing its complexity in terms of number of > triangles and vertices. Luckyly enough the vcg library offers methods for > this kind of clipping that make it in a almost automatic way. Look at the > refine classes. > > Imho both of the two solution are viable. The best things could be to offer > both options to the user and let him choose :) > > I would not consider resampling here. it is somethng that you can always > perform (and probably in a better way) outside meshlab with any image tool, > without touching at all the mesh. > > Do not concentrate too much on the size of the compressed textures. I do > not think that it is the most important issue here. > > Cheers and thanks for your help > p. > > > > skunkwerk wrote: > > thanks Paolo, > page 10 of the paper here: > ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf > discusses this issue, and says you can either use pixel shaders (which > might be possible in meshlab, but not generic viewers) or just repeat the > texture however many times necessary in the atlas itself (wrap or mirror > modes) - i did a quick test in photoshop with a single and tiled texture to > see if it would be able to detect the tiling and not increase the file size > - however the original file was 240k, and the tiled file ended up being 342k > when using PNG. the other option might be to simply resize the tiled > textures to fit into the size occupied by the original texture - but you > would decrease the resolution by doing so. but the 3d viewer at the default > zoom would already display a lower-resolution version of the texture if it > must be repeated within a fixed area, right? so the issue would only be > visible at higher zoom levels - when you might expect the resolution of a > tiled texture to increase, but doesn't. perhaps we could have a > user-selectable value that determines how we tradeoff texture atlas size and > tiled texture resolution? > > graci, > imran > > On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni <pao...@is...> > wrote: > > skunkwerk wrote: > > thanks Paolo, > > sorry - i should have caught that. I'm testing out the code right > > now, and I need confirmation of UV coordinate formats: > > > > 1) if the coordinates are >1 that means the textures are to be > > repeated/tiled, correct? but meshlab can handle this, I don't need to > > change anything. > > 2) what do negative uv coordinates mean? I assumed the origin (0,0) > > was at the top-left corner of the textures. I don't see how you could > > have negative uv coordinates (as i'm seeing in some models) unless the > > origin is in the center. > > > > cheers, > > imran > > > yes texture coords out of the [0..1] range mean that the mesh is using > tiling and assuming that the texture is tiled. Tiling works also in the > negative space. > > Note that when a mesh is using tiling the atalsing procedure it is not > very simple. > a simple clamping the the coords does not work verywell and can produce > weird results. > > For example a triangle spanning from 0.9 to 1.1. cannot be replaced with > a triangle spanning from 0.9 to 0.1, instead of simply crossing the > border thenewe traiangle crosses the whole texture. In this case the > only correct solution, i fear, is to split the triangle in two along the > 1.0 tex coord value, so that we have two trianbgles, a first one > spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. > > - as a first option do a modulo and simply issue a warning. > - as a second option we should clip the mesh. It can be done by using > the refineE and using a edge predicate that splits the edge only if its > textture coords are not inside the 0.1 range. Multiple passes could be > required (separately for each texture coord axis) > > cheers > p. > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR > http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > ------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > ------------------------------ > > _______________________________________________ > Meshlab-devel mailing lis...@li...https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > > > -- > Paolo Cignoni -- Senior Researcher > Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> > > ISTI - CNR > Via Moruzzi 1, > 56124 Pisa > ITALY > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Meshlab-devel mailing list > Mes...@li... > https://lists.sourceforge.net/lists/listinfo/meshlab-devel > > |
|
From: skunkwerk <sku...@gm...> - 2008-05-22 02:25:10
|
i've made further changes to the texture atlas plugin - it should now work with negative uv coords. it is crashing, however on line 197: it causes a segmentation fault, that i've backtraced to qpainter. This does not crash when I do not try to scale the qimage before converting it to a qpixmap. any suggestions? I've tried calling the qpainter destructor before resizing, but that doesn't help. http://meshlab.svn.sourceforge.net/viewvc/meshlab/trunk/meshlab/src/meshlabplugins/filter_texture/filter_texture.cpp?revision=2258&view=markup imran On Wed, May 21, 2008 at 8:00 AM, skunkwerk <sku...@gm...> wrote: > thanks Paolo, > i want to get the first approach working before I try the second one. > > 1) is the current way I'm computing the maximum span correct? > 2) could you please explain what you mean by 'relocating each triangle as > close as possible to the origin'? by origin, you mean the top-left corner > of the texture? are you talking about moving the vertices of the triangle, > or the UV coordinates? > > imran > > > On Tue, May 20, 2008 at 10:17 PM, Paolo Cignoni <pao...@is...> > wrote: > >> Yes, it is not the worst case, but it is something that can happen. >> >> I think that you just need to compute the max span, relocate each triangle >> as close as possible to the origin and then repeat the texture as needed, >> >> Obviously the approach 2): clipping the mesh along the integer values of >> the tex coords is always a good safe option. >> in your case it would have transformed the two triangle mesh in a grid of >> 5x5 vertices and 32 triangles arranges in a regular grid. >> >> You have to define the edge predicate that says what edges have to be >> splitten (the one with texcoords spanning more than 1 >> and the rule to find the position and interpolated values of the new >> vertices. Look at the refine.h file and to the midpoint and EdgeLen classes. >> >> P. >> >> >> >> skunkwerk wrote: >> >> thanks Paolo, >> I think I know what you mean, but is that the worst-case? In the >> drawing I made here: >> www.akbars.net/texcoords.png >> assume each square is composed of two triangles (denoted by the red >> line). The first square shows the normal 0-1 texcoords, no problem. the >> second square shows what I think it would look like when the texture is >> repeated twice along both axes, and likewise for the last square. The >> reason I was thinking about finding the maximum UV coordinates was that I >> could then generate that many copies (so the texture looks like the last >> square) and then for faces that have UVs < 4 (in this case), i'd divide by >> the maximum UVs. So for the second square 2,0 would correspond to 2/4=1/2, >> 0. >> >> by the span of each triangle, i assume you mean the difference between the >> maximum & mininum of the vertexes UV coordinates? with my example, both our >> approaches would be the same I think as the last square's triangle starts at >> 0 and goes to 4 at the bottom. but that obviously wouldn't always be the >> case. so to finalize, what you are suggesting is: >> >> 1) generate an array of Point2f that will store the maximum difference in >> the u & v coordinates for each texture index >> 2) iterate through all faces, and for each face do 6 subtractions to >> figure out the maximum difference for the U & V coordinates of vertexes in >> that face >> 3) if the value computed in 2) is greater than the value stored in the >> array from 1), assign that value to the array >> 4) when done, copy the texture the necessary number of times (as >> indicated in the array), with values rounded up to the nearest integer >> 5) iterate through faces and adjust UV coordinates by the new dimensions >> of each texture >> >> imran >> >> On Tue, May 20, 2008 at 4:08 PM, Paolo Cignoni <pao...@is...> >> wrote: >> >> I think that with a bit of care you can safely apply a same modulo >> operation to the tex coords of the vertex of a same face so that you can >> relocate it as close as possible to the origin of the uv coord system >> >> Explaining better. consider a model of a wall, tessllated (100x100 >> vertexes arranged in a regular grid), this wall is textured with a brick >> texture that is tiled 30 times along u and 40 times along v. There is no >> need to repeat 30x40 times the original texture simply because each triangle >> will not span over many copies of the original texture but in the worst case >> at most two. So in this particular case the needed texture size will be only >> 2x2 times >> In other words you have to look at the maximum span of each triangle, not >> the absolute maximum/minimum. >> >> I have not seen good documents on the web explaining all the gory details >> of this process. Keep this sturff them documented in the wiki :) >> >> Cheers >> p. >> >> >> skunkwerk wrote: >> >> thanks Paolo, >> i'm working on supporting tiling textures right now for the atlas. >> >> i was looking at some 3d models - i have UVs in some of them that are >> 67,-43. That would mean I would have to repeat that texture 67 times in the >> x direction, and 43 times in the y, correct? Do I have to find the maximum >> U & V coordinate of each textures' faces, and scale by that factor? what if >> a different face is using the same texture, but not tiled? are there any >> resources on the web for how to do this correctly? >> >> regards, >> imran >> >> On Mon, May 19, 2008 at 2:04 PM, Paolo Cignoni <pao...@is...> >> wrote: >> >> I would like to avoid the use of shaders, it seems to me a too not general >> solution. Far from the mesh processing spirit of MeshLab. >> >> There are two solutions >> 1) repeating. surely works, but increase the size of the final texture. >> 2) clipping the triangles. a bit harder. as a negative side it changes the >> topology of the mesh, increasing its complexity in terms of number of >> triangles and vertices. Luckyly enough the vcg library offers methods for >> this kind of clipping that make it in a almost automatic way. Look at the >> refine classes. >> >> Imho both of the two solution are viable. The best things could be to >> offer both options to the user and let him choose :) >> >> I would not consider resampling here. it is somethng that you can always >> perform (and probably in a better way) outside meshlab with any image tool, >> without touching at all the mesh. >> >> Do not concentrate too much on the size of the compressed textures. I do >> not think that it is the most important issue here. >> >> Cheers and thanks for your help >> p. >> >> >> >> skunkwerk wrote: >> >> thanks Paolo, >> page 10 of the paper here: >> ftp://download.nvidia.com/developer/NVTextureSuite/Atlas_Tools/Texture_Atlas_Whitepaper.pdf >> discusses this issue, and says you can either use pixel shaders (which >> might be possible in meshlab, but not generic viewers) or just repeat the >> texture however many times necessary in the atlas itself (wrap or mirror >> modes) - i did a quick test in photoshop with a single and tiled texture to >> see if it would be able to detect the tiling and not increase the file size >> - however the original file was 240k, and the tiled file ended up being 342k >> when using PNG. the other option might be to simply resize the tiled >> textures to fit into the size occupied by the original texture - but you >> would decrease the resolution by doing so. but the 3d viewer at the default >> zoom would already display a lower-resolution version of the texture if it >> must be repeated within a fixed area, right? so the issue would only be >> visible at higher zoom levels - when you might expect the resolution of a >> tiled texture to increase, but doesn't. perhaps we could have a >> user-selectable value that determines how we tradeoff texture atlas size and >> tiled texture resolution? >> >> graci, >> imran >> >> On Sun, May 18, 2008 at 10:58 PM, Paolo Cignoni < >> pao...@is...> wrote: >> >> skunkwerk wrote: >> > thanks Paolo, >> > sorry - i should have caught that. I'm testing out the code right >> > now, and I need confirmation of UV coordinate formats: >> > >> > 1) if the coordinates are >1 that means the textures are to be >> > repeated/tiled, correct? but meshlab can handle this, I don't need to >> > change anything. >> > 2) what do negative uv coordinates mean? I assumed the origin (0,0) >> > was at the top-left corner of the textures. I don't see how you could >> > have negative uv coordinates (as i'm seeing in some models) unless the >> > origin is in the center. >> > >> > cheers, >> > imran >> > >> yes texture coords out of the [0..1] range mean that the mesh is using >> tiling and assuming that the texture is tiled. Tiling works also in the >> negative space. >> >> Note that when a mesh is using tiling the atalsing procedure it is not >> very simple. >> a simple clamping the the coords does not work verywell and can produce >> weird results. >> >> For example a triangle spanning from 0.9 to 1.1. cannot be replaced with >> a triangle spanning from 0.9 to 0.1, instead of simply crossing the >> border thenewe traiangle crosses the whole texture. In this case the >> only correct solution, i fear, is to split the triangle in two along the >> 1.0 tex coord value, so that we have two trianbgles, a first one >> spanning from 0.9 to 1.0 and a second one spanning from 0.0 to 0.1. >> >> - as a first option do a modulo and simply issue a warning. >> - as a second option we should clip the mesh. It can be done by using >> the refineE and using a edge predicate that splits the edge only if its >> textture coords are not inside the 0.1 range. Multiple passes could be >> required (separately for each texture coord axis) >> >> cheers >> p. >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> ------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> ------------------------------ >> >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> >> >> -- >> Paolo Cignoni -- Senior Researcher >> Visual Computing Laboratory - ISTI - CNR >> http://vcg.isti.cnr.it/~cignoni <http://vcg.isti.cnr.it/%7Ecignoni> >> >> ISTI - CNR >> Via Moruzzi 1, >> 56124 Pisa >> ITALY >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Meshlab-devel mailing list >> Mes...@li... >> https://lists.sourceforge.net/lists/listinfo/meshlab-devel >> >> > |
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From: Paolo C. <pao...@is...> - 2008-05-22 06:50:28
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skunkwerk wrote: > i've made further changes to the texture atlas plugin - it should now > work with negative uv coords. it is crashing, however on line 197: > > it causes a segmentation fault, that i've backtraced to qpainter. > This does not crash when I do not try to scale the qimage before > converting it to a qpixmap. any suggestions? I've tried calling the > qpainter destructor before resizing, but that doesn't help. > > http://meshlab.svn.sourceforge.net/viewvc/meshlab/trunk/meshlab/src/meshlabplugins/filter_texture/filter_texture.cpp?revision=2258&view=markup > <http://meshlab.svn.sourceforge.net/viewvc/meshlab/trunk/meshlab/src/meshlabplugins/filter_texture/filter_texture.cpp?revision=2258&view=markup> > > imran > I gave a very short look at the code. A few suggestions (that in most cases holds for all my students too....) - keep the implementation of the filters out of the apply methods unless it is a very short one (e.g. less than 10~20 lines of code). The ApplyFilter function should be mostly a switch. - try to structure your code a little more. Avoid very lengthy functions. - multiple atlases seems to me a bit a weird concept. The idea of atlases is exactly the fact of having a single unique object. Let us assume that the objective is an unique single atlas. - You are doing a quite restructuring algorighm so it reasonable an initial purging step. Perform at beginning a compactVertex and comapctface call and get rid of all the IsD() tests in your loops. - Do not take any care of number of multiplications, sums and operations. Performance is affected by other things. Forget old style optimizations.... - stl has min and max, use them. - pay attention to use int for truncating a value, floor and ceil make a more predictable work, particualrly when negative numbers are around - 2880 seems to me a quite weird value for a maximum texture size. Where do it came from? why not a plain 4096 or 8192? - on my machine, on the input mesh sample/texture_double.ply it does not crash, but simply create trashed tex coords. From the log: created atlas of dimensions: 1024 , 512 inserted texture 0 into atlas at position: 0 0 inserted texture 1 into atlas at position: 512 0 saved texture atlas original U: 0 original V: 0 new U: 2.82017 new V: 9300.4 original U: 1 original V: 0 new U: 2.82017 new V: 9300.4 original U: 1 original V: 1 new U: 2.82017 new V: 9300.41 original U: 0 original V: 0 ... Cheers p. -- Paolo Cignoni -- Senior Researcher Visual Computing Laboratory - ISTI - CNR http://vcg.isti.cnr.it/~cignoni ISTI - CNR Via Moruzzi 1, 56124 Pisa ITALY |
