Description: We present a technique to create rich vector graphics using intuitive controls, as the solution of a global relaxation. In the simplest setting, an artist sketches outline curves, and then sprinkles interior color constraints to obtain a smooth interpolation. This “ink and paint” style of interaction is similar to traditional hand drawing. It is fun to use, as minimal user input expands to create free-flowing graphics. Additional features such as creases, contour lines, and gradient curves offer powerful editing control to refine the drawing.

Our key contribution is to perform interpolation using a least-squares harmonic function, and to adjust this functional to support the myriad desired features. We present a system that evaluates the graphics in real-time on a dual-processor PC.