Re: [Plib-users] plib and shadows

[Steve B. <sjb...@ai...>]

> I'm still trying to get shadows.
> Now I reduced the code so that stencil buffer is not (yet) used, I just want 
> to see the projection of my scene to the ground.
> There is a callback function for predraw which is being called.
> I tried two ways :
> - use a glMultMatrixf((GLfloat *) floorShadow) in the callback function, 
> where floorShadow is the projection matrix

You can't do that because SSG culls the scene to the view frustum prior to
drawing it - so if you go and change the transforms without SSG knowing about
it, you'll get into problems.

 > - use a setTransform(floorshadow) before calling ssgCullAndFace

> Both don't show a projection, the second shows parts of the scene at a 
> different place.
> My guess is the first is superseded by ssg functions and the second is a 
> transformation but not a projection. Could that be ?

Yes - transforms are limited to rotates and translates.  It's not possible
to do bounding sphere culling when the transform is not shape-preserving.

----------------------------- Steve Baker -------------------------------
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