/// <summary>
///
/// </summary>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <returns></returns>
public static Vec3d GetIncenter(Vec3d p0, Vec3d p1, Vec3d p2)
{
double d01 = p0.DistanceTo(p1);
double d12 = p1.DistanceTo(p2);
double d20 = p2.DistanceTo(p0);
double pInv = 1.0 / (d01 + d12 + d20); // inverse perimeter
return(p0 * (d12 * pInv) + p1 * (d20 * pInv) + p2 * (d01 * pInv));
}