public Matrix3d getViewMatrix(int index) {
Matrix3d m = new Matrix3d();
switch (index) {
case 0:
m.setIdentity(); // C4 vertex-centered
break;
case 1:
m.rotX(-0.5 * TETRAHEDRAL_ANGLE); // C3 face-centered 2.0*Math.PI/3
Matrix3d m1 = new Matrix3d();
m1.rotZ(Math.PI / 4);
m.mul(m1);
break;
case 2:
m.rotY(Math.PI / 4); // side face-centered
break;
default:
throw new IllegalArgumentException("getViewMatrix: index out of range:" + index);
}
return m;
}
public IfcPosition3d(Vector3d origin) {
this.origin = origin;
M = new Matrix3d();
M.setIdentity();
}