ShadowPix: Multiple Images from Self Shadowing

ShadowPixare white surfaces that display several prescribed images formed by the self‐shadowing of the surface when lit from certain directions. The effect is surprising and not commonly seen in the real world. We present algorithms for constructing ShadowPixthat allow up to four images to be embedded in a single surface. ShadowPixcan produce a variety of unusual effects depending on the embedded images: moving the light can animate or relight the object in the image, or three colored lights may be used to produce a single colored image. ShadowPixare easy to manufacture using a 3D printer and we present photographs, videos, and renderings demonstrating these effects.