   Is there a simple way to test for alpha in a texture?
  I want to be able to flag my sprites as having translucent areas or not. I'd also like to be able to do this at the point the texture is created, and without the knowledge of the user of the texture. Is there an easy way of doing this, or can I just search through the texture like an array and test each pixel's alpha value? Or should I just force the user to tell whether the sprite is translucent when the sprite is created?   
  You can test the pixels on the CPU side, or use an occlusion query (I have an example of this here).   