docs: private void perturb(double disturbance , Point2D_F64 pixel , Point2D3D p23 ) {
  		double x;
  		double y = pixel.y;
  
  		x = pixel.x + disturbance;
  		computeDisturbance( x,y, p23);
  		x = pixel.x - disturbance;
  		computeDisturbance( x,y, p23);
  		x = pixel.x;
  		y = pixel.y + disturbance;
  		computeDisturbance( x,y, p23);
  		y = pixel.y - disturbance;
  		computeDisturbance( x,y, p23);
  	}