while i am getting 52fps when using GL_LINEAR_MIPMAP_LINEAR for my textures,when i use GL_LINEAR only, fps drops to 27s. what’s wrong?

my main problem is here: opengl do not read the alpha values of a tga file when i use mipmapping(transperant pixels seems black), when i don’t use mipmapping alpha is ok, but performance drops to its half.

help me, please!!!

Mipmapped textures are more cache-friendly then non-mipmapped textures. This means with mipmapped textures, you have a greater chance of finding a desired texel in the cache instead of going all the way out to the memory to get it. This performance hit is most notable when you map a large (relative) texture onto a small primitive.

Show us some code regarding the problem with the alpha channel.