Particle Shader, is there any example?

[Shadowsong]

Hey I want to create a particle shader. So in fact a shader which I can pass to TVParticleSystem.SetBillboardShader(...).

I guess that such a shader is different from a mesh shader and would probably look more like a minimesh shader using a matrix array or something like that. But it seems like nobody has ever written a particle shader.

So, is it even possible?

Actually, what I want to do is very simple: I have particle emitters set up with keyframes which store a color. Now I need to multiply that color with a float. And this needs to be done every frame because this factor changes over time. Is there any way to do this without a shader?