Quote:Original post by ZipsterThat method is only accurate for additive blending, since straight addition is commutative. But other blending modes such as SRC/INVSRC give different results depending on render order.
While this may be technically true, the method of using the z-buffer without z-write is still useful in a lot of particle situations. Even without additive blending (smoke, etc.) the particle system will usually look fine unless you have very few or very large particles. I think it's visually more important for the 'primary' geometry to blend correctly with the particles than for the particles to blend in proper z-order with each other.
Basically all I am saying is don't throw this technique out the window as an inferior hack, it has many valid uses!
