Re: [sgl-dev] SGL and TuxFleet

[Scott M. <mcm...@ca...>]

First, it is unfortunate you use the testLoader program has
the example for some aspects of SGL.  It illustrates a complex
way of doing traversals.  Some of the simpler test programs
are better for this.  I am enclosing changes that I have made
to your class (I have not compiled this b/c I don't have the
TuxFleet or PLIB installed)....


Here are some comments:

- In order to better help you I need to understand what the
member functions are supposed to do.  For
example what does it mean to "setup the ith light", are fov's
in radians, are fov values half field values, how are the
lights supposed to behave? etc. etc.

- You must make sure that a proper graphics context is current
when calling sgl::initialize() which means when you construct
this object.

- Also are you driving the view postion and orientation by
setting the camera view matrix?  That is, do you have some
external code that determines where you are in the 3D
world and then you call FleetSceneSGL::setCamera.  If
this is the case, then you do not really need the zup_camera.
In the code I am sending back I have removed this.
I also may need to know what the implied coordinate system of
the viewing camera is supposed to be.

- SGL does nothing to set up the proper viewport or GL projection
matrix.  If you do not do this elsewhere than there need to be
commands in FleetSceneSGL (the sglu cameras do not do this
for you).  I have added a call to set up the projection matrix
but the glViewport command is missing.

- SGL does not currently have support for lights in the scene.
If these lights need to in a constant position relative to the
scene (and not the viewer) then additional code is needed in
cullAndDraw to make sure they are positioned after the camera
matrix is applied.  I have implemented a crude way to do this
in the code I am sending you, but I really don't know what the
proper functionality was so I made some guesses.

scott

P.S. If the intent is to not depend on any PLIB code, then the
interface to wrapper classes like this (and any other core code)
should not depend on types defined in PLIB (or SGL).  That is,
you should not pass parameters of type sgVec4.  Instead you
should use something more generic like float[4];


Alexander Rawass wrote:
> 
> Hi,
> 
> I've been working a bit on fleet_scene_sgl* for TuxFleet.
> 
> TuxFleet compiles for sgl now, it even runs with sgl - but no 3d models
> get drawn yet.
> 
> Please have a look at the files in attachment.
> Did I make any obvious mistakes there?
> 
> Do I set the Camera correctly?
> 
> Do I initialize the scene correcly?
> 
> Is the cullAndDraw()-routines okay somehow?
> 
> Alex

-- 
Scott McMillan                        mailto:mcm...@ca...