i have big problem when opengl display very small triangle in texture mapping, it displays as red segments… there is a opengl call to eleminate this noisy effect=

Try downloading the texture as mipmaps and use GL_LINEAR_MIPMAP_LINEAR as minfilter.

Thx for your solution but doesn’t work i just use mipmapping!!

Everything else would be guesses. Here are some:
Where does the red come from?
Is there red on your texture?
Could it be a wrong texture level of detail?
Do you overclock your board?
Is this deterministic or random?
Can you isolate a single faulty polygon?
Debug it!

if you’re using mipmapping and the small triangle is red, that mean that the small textures in your mipmaps is red !!!
how do you generate the mipmaps ??? gluBuild2DMipmaps ???

maybe the glu function is not appropriate for this texture. generate your own mipmap with a good filter function which doesn’t make your texture red when approching small textures.