update method

void update()

Implementation

void update() {
  _v1.setFromMatrixPosition(light.matrixWorld);
  _v2.setFromMatrixPosition(light.target!.matrixWorld);
  _v3.sub2(_v2, _v1);

  lightPlane.lookAt(_v2);

  if (color != null) {
    lightPlane.material?.color.setFrom(color!);
    targetLine.material?.color.setFrom(color!);
  } else {
    lightPlane.material?.color.setFrom(light.color!);
    targetLine.material?.color.setFrom(light.color!);
  }

  targetLine.lookAt(_v2);
  targetLine.scale.z = _v3.length;
}