2d Convex Hull

A 2d convex hull is nothing new, but here we can control the number of vertices.

First we create the hull with Triangulate 2d and Divide, and measure edge lengths. Then we recursively collapse edges by finding the shortest edge and collapsing it into the intersection of the neighboring edges. Repeat until N points remain.



Wispy Clouds

You can get wispy clouds by doing extreme extreme volume displacement by some nice noise. Here I have a planar volume and I’m only displacing along the volume (Y displacement multiplied by 0) so I don’t even need to enlarge the displacement bounds.



Face Contours

Back again. This started as something else, but ended up with finding contours. I calculate the difference between a sphere and a face, and in uv-space get the curl, which is then projected back onto the mesh.


Max velocity volume blending

Velocity volume blending has always had a glaring omission in my opinion. Add mode gets out of hand, Blended Average values are hard to nail down, what I want is to pick the greater velocity from the existing vel and my new source vel. I’m sure most users think that’s what Maximum mode is, but it is not! In fact it picks the larger numeric value for each component – so if you have a volume of {0,0,0} and you try to blend in some {-2,0,-2}, you still end up with a volume of all zeros. This is easy to confirm with the attached scene by bypassing the added switch node.


The attached scene has an additional Field VOP that overrides the default Maximum behaviour with what I think is the more logical operation – the longer velocity vector is picked for each voxel.