InputHandler#pixelPerfectOver

Set to true to use pixel perfect hit detection when checking if the pointer is over this Sprite.
The x/y coordinates of the pointer are tested against the image in combination with the InputHandler.pixelPerfectAlpha value.
This feature only works for display objects with image based textures such as Sprites. It won't work on BitmapText or Rope.
Warning: This is expensive, especially on mobile (where it's not even needed!) so only enable if required. Also see the less-expensive InputHandler.pixelPerfectClick. Use a pixel perfect check when testing for pointer over.