You probably want to draw curves and polygons then fill them. It's possible to imagine drawing extra thick lines by modifying the algorithm but the equivalent

You probably want to draw curves and polygons then fill them. It's possible to imagine drawing extra thick lines by modifying the algorithm but the equivalent changes to a curve would leave gaps. I suppose you could figure out how eg boundary paths for beziers are calculated and transform your algorithm so each step draws to the boundary. It seems like more work for something less general than filling though.