Monday, August 21, 2017

Moment of Inertia of a Distance Field

While adding physics support to my voxel engine I needed a reasonable accurate & fast method to calculate the moment of inertia, volume, and center of mass for an arbitrary distance field.

I've written this C++ code to do so.
Feed it a regularly spaced grid of points and distances.
The points must fully bound the negative space of the field to be accurate.

The common primitives, such as a sphere, there are established formulas that we can compare against.

For a 10^3 distance field of a sphere, the estimate is off by about 1%, close enough for me.
If more accuracy is needed, the sample rate can be increased.

Thursday, January 5, 2017

Video of my Distance Field Engine

This is a short clip showing my engine. 
It uses distance fields to represent all geometry.
Don't confuse it with a minecraft like engine--those use 1 bit filled/not filled.
It is written in very SIMD heavy C++.