voronoi seed points

[MENOZ]

Hello people!

I was thinking if there is a way to use some scattered points ad "seed points" for the voronoi texture, basically the same thing that happens with the voronoi fracturing, but at shader level. I want to control the placement of the cells.

cheers!

[DanBode]

Sure, you can do this pretty easily with point clouds. I don't have time to make an example at the moment, but if you first write out a bunch of points to a .pc file (or .bgeo I guess but .pc is a little faster). In the shader throw down a "point cloud open" vop, point the file param to your .pc file, then make the radius really huge, and set the max points to 1. Take P from the global inputs, run it through a transform vop, to move it from current to object space, then pipe it into the P input on your "point cloud open". Pipe the handle output of "point cloud open" into a "point cloud import by index" vop, set the Channel to "point.number" and the signature to integer. This will grab the number of the point in your point cloud that is closest to the current point being shaded. To get the classic voronoi look, pipe that point number into a random and output a vector, and pipe that vector into Cf.

[MENOZ]

hey thank you. I was thinking about using point clouds, but i didn't think to use the point cloud import by index. I will try that. Thank you!

[DanBode]

Good luck! Point Cloud Import By Index and Point Cloud Num Found are two of my favorite additions in Houdini 12.