Question by metervara · Mar 23, 2012 at 11:32 AM · particles particlesystem

Particle distribution on mesh: How to implement a density map?

I'm trying to control the density of particles across a mesh when using a mesh-shape for the emitter. I have vertex colors on the original mesh to be used for the density map and need help on finding a good approach to the problem.

My current idea is to iterate through the triangles in the mesh and calculate a percentage of the surface area for that triangle compared to the entire mesh. Then multiply that percentage with the averaged density (vertex color) of the 3 vertices for that triangle to get a particle count(percentage) for the triangle. Finally I would randomly distribute the particles on the triangle.

I think the main problem with this approach that the density will be per triangle, so large triangles where the vertices have different colors won't get a nice 'gradient' distribution.

Input appreciated.

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DaveA · Mar 23, 2012 at 08:11 PM 1

Are you writing your own particle system, or are you planning to instantiate particle emitters over the faces of the mesh?

metervara · Mar 26, 2012 at 08:04 AM 0

I'm using unity particles, only want to tweak the distribution a bit. $$anonymous$$ost likely I'll use SetParticles and the $$anonymous$$esh interface to distribute the particles.