makePlaneReflection function
Returns a transformation matrix that transforms points by reflecting
them through the plane specified with planeNormal
and planePoint
.
Implementation
Matrix4 makePlaneReflection(Vector3 planeNormal, Vector3 planePoint) {
final v = Vector4(planeNormal.storage[0], planeNormal.storage[1],
planeNormal.storage[2], 0.0);
final outer = Matrix4.outer(v, v)..scale(2.0);
var r = Matrix4.zero();
r = r - outer;
final scale = 2.0 * planePoint.dot(planeNormal);
final scaledNormal = planeNormal.scaled(scale);
final T = Vector4(scaledNormal.storage[0], scaledNormal.storage[1],
scaledNormal.storage[2], 1.0);
r.setColumn(3, T);
return r;
}