I’m trying to make an impostor of a tree, so
I render this object and read a subregion of the framebuffer with glCopyTexSubImage2D(GL_TEXTURE_2D,0,0,0,x,y,width,heigth);
I’m loading in a RGBA texture.
But it’s impossible to get the alpha channel from the framebuffer.
Before rendering my object, I have cleared the alpha channel of the buffer by
glClearColor (1.0,1.0,1.0, 0.0) but it doesn’t work either.
Can anybody help me, please?