code: public void clip() {
          int x = (int) (projection.canvas.getWidth() * projection.canvas.margin);
          int y = (int) (projection.canvas.getHeight() * projection.canvas.margin);
          int w = (int) (projection.canvas.getWidth() * (1 - 2 * projection.canvas.margin));
          int h = (int) (projection.canvas.getHeight() * (1 - 2 * projection.canvas.margin));
          originalClip = g2d.getClip();
          g2d.clipRect(x, y, w, h);
      }
docs: Restrict the draw area to the valid base coordinate space.