Shadowmaps....again :)

glMatrixMode(GL_TEXTURE);
glLoadIdentity();
SetupCam(light);

something like this.. go for projected textures.. never have i done this, but its supported in gl. good luck. hope someone can help more precicely

"take a look around" - limp bizkit
www.google.com

The depth texture projection is not a separate pass, it''s included in your DrawModel and DrawTerrain passes. It uses multitexturing on an additional texture unit.

You have to use projective texture mapping. You have different options to create the required texture coordinates. The easiest is simply to feed the 3D position of your vertex (the one you give to glVertex() or similar) also to the textue coordinates of the shadowmap unit: just assign s=x, t=y, r=z, q=1. For that to work, you''ll have to load the projection matrix you used to render the view from the light into the texture matrix, including the premultiplied modelview matrix. The s,t,r,q coordinates will now be transformed and projected, just the same way they were when you rendered the light. The difference is, that now they are texture coordinates.

You''ll have to do some range and offset adjustments to your texture projection matrix, so that the projection and the rendered lightview match. Once you have that working, all you have to do is enable the shadowmap test through SGIX_shadow and create an appropriate combiner environment, so that you can see the shadow effect (best done through register combiners).

/ Yann

when I suggested textur based shadows in the other topic, I did not mean shadow depth textures. It''s my opinion they are more a gimmik than really useful.
All I meant was draw the model black, on a white background (no depth writing/teststing needed) then render it onto the terrain as a lightmap. Will run on any hardware, and be a LOT faster, while looking just as good. Just you''d have to do the alpha component trick I mentioned.