particle age UVW gradient

[ldotchopz]

Did you look at the UVW Gradient official sample scene? That's the standard way to control particle colors by age or other triggers.

I guess your setup is slightly different because you're not controlling particle colors on the whole, but instead having a gradient travel up a spline once triggered. That's an interesting dilemma....my intuition would be to have 2 map channels...one to set the UVWs required to have the gradient go from bottom to top, and the other to control the V offset of the first channel (this would be what you control with particle data). Might have to involve some OSL as well to get it to work (read the V value of map channel 2 and apply that as an offset to the V value of map channel 1).

Believe it or not i actually found a solution an acient vray forum using the original Pflow.

check it out. would be awesome to have this as easy in tyflow, could make for some great effects. 
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