A Sprite is a Raster


	class Sprite extends Raster {
	    int x, y;                       // position of sprite on playfield
	    public void Draw(Raster bgnd);  // draws sprite on a Raster
	}

    Things to consider:



The Draw( ) method must handle transparent pixels, and it must
also handle all cases where the sprite overhangs the playfield.
Lecture 2   Slide 12   6.837 Fall '01