Game Development Reference
An important point to note before we move on is that Bullet assumes the center of
mass of the object is at ( 0 , 0 , 0 ) relative to the given points, ergo the points must be
defined around that location. If we wish to set the center of mass to a different loc-
ation, then we must call the setCenterOfMassTransform() function on the ob-
ject's rigid body.
Creating convex hulls from mesh data
Building a convex hull by manually typing in the vertex data can be incredibly tedi-
ous. So Bullet provides methods for loading customized mesh file data into the de-
sired vertex format that we used earlier, provided the data has been stored in the
.obj format (a common format that every 3D modeling tool supports these days).