Conventional digital painting systems rely on procedural rules
and physical simulation to render paint strokes. We present an
interactive, data-driven painting system that uses scanned images
of real natural media to synthesize both new strokes and complex
stroke interactions, obviating the need for physical simulation.
First, users capture images of real media, including examples
of isolated strokes, pairs of overlapping strokes, and smudged
strokes. Online, the user inputs a new stroke path, and our system
synthesizes its 2D texture appearance with optional smearing or
smudging when strokes overlap. We demonstrate high-fidelity
paintings that closely resemble the captured media style, and also
quantitatively evaluate our synthesis quality via user studies.