I've problems with the alpha value when I read from a textured image from the screen.
First of all, I use glReadPixels(0,0,width,hight,GL_RGBA,GL_UNSIGNED_B YTE, *frame);
After chanching the Blue with the Red values, I get a tga file. But when I see it with the Photoshop, the alpha chanel is completely white!!
Can I read RGBA from the screen or I can get only RGB values?