De-intersecting extruded polygons in for each loop

[hmihalis1]

Hi there, 

I'm working on adapting this effect to grow crystals on an animated character. 

so far I have created a color map which drives the density of the crystals, which i've bound to a mesh_density value fed to a remesh node to remesh the body of the character with bigger polygons at the centre and smaller ones as the color falls off, then divided it to get hexagons and extruded them out  using some VEX that i've just guessed at, the zscale is calculated from the mesh_density but remapped a bit, and with some randomness applied: 

My main problem now is how to de-intersect the extruded geometry. I was thinking I could use a measure SOP in the loop and all the crystals into a large group and a small group, then cut the ones in the small group off wherever they intersect a larger crystal. 

Once I have this done the plan is to take the crystals in the large group and extend the loop for them so they can cut off at random angles at the top+some additional details as explained in the CGMonkey/Entagma tutorials covering minerals. 

So my questions are: 

1. How to check for intersections in extruded geometry and bool a smaller group from a larger group

2. How to make the VEX in this wrangle better so I can control the random heights and fall offs with values and curves.

2. Will point deform work to stick this geometry back onto my animated creature? 

To be clear, my effect is a static encrustation of crystals on this lizard which is animated, I don't need to figure out the crawl on animation in the above video.

Any help is very much appreciated! 

Thanks, 

H

 

 

 

crystal_growth_001.hipnc