public PixelEval(Scene scene, RGBImage image, int rs, int re, int cs, int ce, double dx, double dy) {
			super();
			this.scene = scene;
			this.image = image;
			this.rs = rs;
			this.re = re;
			this.cs = cs;
			this.ce = ce;
			this.dx = dx;
			this.dy = dy;
		}