1. A computing device that comprises: a processor; and a memory that comprises a paint simulation system that is executed by the processor, the paint simulation system comprising: a computer-implemented canvas that comprises a paint map that comprises first cells, the first cells have first values assigned thereto, each value in the first values is indicative of a color and an amount of paint at a location on the computer-implemented canvas of a respective cell in the first cells; and a plurality of components, comprising: a brush component that outputs a three-dimensional computer-implemented model of an image editing tool in contact with the computer-implemented canvas, a footprint defines a region on the computer-implemented canvas where the three-dimensional model of the image editing tool is in contact with the computer-implemented canvas; and a paint component that generates a two-dimensional paint pickup map for the footprint, the paint pickup map comprises second cells that have second values assigned thereto, each value in the second values is indicative of a color and an amount of paint on the model at a location of a respective cell in the second cells of the footprint, resolution of the paint pickup map matches resolution of the paint map, the paint component updates values of the second cells based upon values of the first cells when the model is transitioned over the computer-implemented canvas.