I’m making an application that shows differences between different texture filtering methods. In my mind, from worse to best, it is:
normal->linear->bilinear->trilinear->anisotropic.
Linear works well, smoothing the texture. Then bilinear makes the texture looks better when it’s far, and it’s also faster. Anisotropic is a great effect that is easily noticeable over any other filter.
But I just can’t see any difference between bilinear and trilinear. I know trilinear is supposed to have a less foggy effect that bilinear, like a trilinear texture at 10 meters have the same quality as a bilinear texture at 5 meters.
It just doesn’t work for me. I have a Geforce Titanium with latest drivers and Windows XP. I know it does support trilinear because I can change it in my drivers settings(force bilinear, force trilinear or force none, but it doesn’t seems to change anything). Now I was thinking that my card may use trilinear whatever I choose, just because trilinear looks better without too much performance loss.
Or maybe my coding is wrong? I simply use
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
for bilinear, and then
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR_MIPMAP_LINEAR);
for trilinear. Mip mapping is actived for both indeed. Anyone have experienced with bilinear and trilinear?