Hi!! Can you please help me with this lightmapping problem: I seem to have seams at the edges of polygons and can't understand why, take a look here please http://www.godsofasgard.as.ro/engleza/images/uniform%20density1.JPG http://www.godsofasgard.as.ro/engleza/images/bad1.JPG http://www.godsofasgard.as.ro/engleza/images/wireframe.bmp.JPG So what could possibile be wrong? Here's how I create the lightmaps glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexImage2D(GL_TEXTURE_2D, 0, 3, LIGHTMAP_SIZEW, LIGHTMAP_SIZEH, 0, GL_RGB, GL_UNSIGNED_BYTE, pPolygon->lightmap); Please, where could the problem be?

In fact each triangle there get's a different texture for lightmapping, but how are the pixels from the edges are affected by filtering with illegal pixels? I mean there's no way out of the texture is it? and the seams do not appear on the diagonal edges there... They only appear on the sides of the texture, so how and by what illegal pixels(out of the map, that do not show on the screen) are affected the good pixels around the edges? Please clarify this for me, I'm a little :) confused

You are using bilinear filtering so each pixel is a blend of four texels. When you sample in the middle of your lightmap texture you are averaging four *different* texels. Not so at the edges, due to the clamping. In the corners, where both u and u are clamped, the four sampled texels will be the same.

one solution for this problem is to scale down the UVs a little bit (about a half texel) to the center of your polygon.