Archives For Animation

I’ve been having a serious look at using spheres and also boxes to represent the collision
shape in bullet simulations. Spheres are great in that you can rely on the geometry to not get caught and hang on to each other. Boxes offer a nicer settling motion in certain setups too. The main reason I wanted to look at it, was to avoid always needing to use glue constraints. Sometimes I want a nice quick voronoi fracture that uses the clustering option, and this yields shitty collision approximations with convex hulls.

Enter vdb sphere packing! It allows me to fill the wacky geometry shapes and use those as colliders. I just save out my points, and transform the original pieces. Voila!



Houdini Coordinate System

December 18, 2016

Here’s a quick visual for understanding the right-hand coordinate system that Houdini uses. Note in the second image, if you point your thumb in the + direction of an axis, and curl your fingers, the curl direction is the positive direction for rotation around that axis.

This is a product of being a right-hand coordinate system. It also controls the default direction of the cross product.



[vimeo 131941068 w=660 h=281]

Houdini Contact Maps

March 7, 2015


March 7, 2015


FLIP Variable Viscosity

January 1, 2015

Let us kick this thing off!

December 7, 2014

So here we go!