I’m trying to reproduce something that can be done in Houdini where you can change a vertex color according to its velocity. Like the faster it moves the whiter it becomes. Would it be possible?
This one should work (cycles only though I think) Made happier colors though.
you can control it better with adding a math node after the velocity output, set it to exponent or something nice.
Yeah, I tried but it didn’t work. And I’m trying to do this on vertices, not particles. But thanks for trying. 
Ah, misread it, sorry. Vertex velocity… not that I know if, even if you have a static particle on a vert of a deforming mesh to transfer the color information from, it wouldn’t have velocity to measure. No clue how to do that, maybe with animation nodes it’s possible, but I didn’t really look into that that much yet.