1. A method for simulating the effects of layered fog in a computer-generated synthetic environment, wherein aliasing is eliminated at a boundary between regions of the layered fog that have different densities, and wherein the boundary of the regions of the layered fog lies between adjacent pixels, said method comprising the steps of: (1) generating a plurality of sample points for each of the adjacent pixels that lie on the boundary of the layered fog regions; (2) calculating a layered fog density for each of the plurality of sample points; and (3) blending the layered fog density that is calculated for each of the plurality of sample points to thereby form an anti-aliased pixel layered fog density value for each of the adjacent pixels.