1. A method, comprising: performing, by one or more computing devices: accessing a predicted background color for a shape, wherein the shape corresponds to a bitmap generated from a mask of the shape; compositing the predicted background color with a background color of the bitmap for the shape to create a composited background; generating a rendering of the shape, wherein the rendering is based on the composited background, a color of the shape, and the mask; removing one or more elements of the composited background from the rendering of the shape; and creating a smoothed bitmap of the shape, wherein said creating comprises compositing, after said removing, the rendering of the shape with a destination background.