Re: [Clusterviz-devel] Change rotation center

[Jonas M. <na...@us...>]

Hey,

On Monday 23 January 2006 16:33, K.W...@gm... wrote:
> Hello!
> Changing the rotation center is not that difficult. Here is
> a revised version of recalculateTransformationMatrix:
>
>     def recalculateTransformationMatrix(self):
>         glPushMatrix()
>         glLoadIdentity()
>         glTranslatef(-self.center[0], -self.center[1], -self.center[2])
>         glRotated(self.angle, self.axis[0], self.axis[1], self.axis[2])
>         glTranslatef(*self.center)
>         glMultMatrixf(self.transform)
>         self.transform = glGetFloatv(GL_MODELVIEW_MATRIX)
>         glPopMatrix()
>
> Note the two calls of glTranslate.

Great! It works exactly the way I imagined it.

> I could not access the svn respository. It says
> svn: PROPFIND Anfrage fehlgeschlagen auf '/InfoTheory'
> svn: PROPFIND von '/InfoTheory': Autorisierung fehlgeschlagen
> (https://cvs.molgen.mpg.de)
> after I entered the username Janne sent me.

I can not reproduce any problems with the repository, so the problem must be 
related to your credentials. Maybe Janne can help out?
Otherwise I might reconsider duplicating the svn-content into my private 
svn-server which I can readily administrate.

I commited your above cited recalculateTransformationMatrix in the meanwhile.

> Concerning the scale parameter, I am stuck. What do the near and far
> parameter in gluPerspective mean?

These two are distances from the eye point to clipping planes. Variable near 
specifies the minimum distance in front of which the objects are clipped and 
not shown. Variable far specifies the farthest distance behind which objects 
are clipped. Consider this (please use fixed font):

                            /-------|---
                /-----------        |
         /---|--                    |
    _/---    |                      |
x-<=_        |     Objects shown    |  Objects clipped
     \---    |                      |
         \---|--                    |
                \-----------        |
                            \-------|---
|<--near---->|              
 Objects
 clipped

|<----------far-------------------->|


Hope to help,
kind regards, Jonas.