int jswrap_graphics_getPixel(JsVar *parent, int x, int y) {
  JsGraphics gfx; if (!graphicsGetFromVar(&gfx, parent)) return 0;
  return (int)graphicsGetPixel(&gfx, (short)x, (short)y);
}

The product reads data past the end, or before the beginning, of the intended buffer.