Original Post
Is there any way to render a particle system (with additive blending) such that particles blend with each other, but not anything else? i.e., say I render a particle system against a black background with additive blending (src = D3DBLEND_ONE, dest = D3DBLEND_ONE). This achieves the effect I want to have, but whenever I render the particle system agains't a non-black background, it adds in the background colors, as would be expected. Is there any way to blend particles with each other, but not with anything else, say the background? So far the only way I can think of/found is to render the particles twice, the first pass with the renderstates set to (D3DBLEND_INVSRCALPHA,D3DBLEND_ZERO) then the second time set to (ONE,ONE). However, when trying this, the resulting image has black around the edges. (the particle's texture is a dot, white at the center fading towards black at the edges) What I currently have working is a particle engine that works fine against a black background, but when rendered against say a green background, the edges turn up a bright green tint. Not good since of the effect I'm going for is an explosion... Has anyone achieved this effect? Whether by setting up renderstates a certain way, or giving up and doing it through a new approach. I envision the final effect to be something like d000hg has... How'd you do that d000hg? -_-
