calculateMassInfo method
Calculate the mass information of the shape.
Implementation
@override
void calculateMassInfo( out ) {
double mass = volume() * radius * radius * density;
out.mass = mass;
double inertia = mass * radius * radius * 0.4;
out.inertia.set( inertia, 0, 0, 0, inertia, 0, 0, 0, inertia );
}