Alpha Optimization

Ok, me again with another question for the gurus… (Hopefully my questions are becoming less newbie… ;))

In another post I mentioned that I’ve been porting a particle system. In that system, each particle can have an alpha value. When the alpha value is less than 1.0, the system slows down quite a bit. iirc, this is do to how blending works. Is this something I can optimize…? I’ve thought about using an off screen buffer to render the particles and then blend them all at once into the scene, but that seems like it might not give the same effect unless I use blending on that other buffer anyhow.

Any thoughts?

No, there’s nothing you can do about this. If you want blending, you’ve got to pay for it.

Orangytang had a suggestion of setting the alpha test to some slightly higher value, say 0.1f, which would cut out a lot of almost-completely-invisible pixels and maybe save you a bit of fill rate.

Cas :slight_smile: