Structural coloration means that the microstructure of an object causes various colors to appear. For industry, this is an attractive alternative to coloring with pigments. But so far, scientists had primarily experimented with nanostructures observed in nature, or with simple, regular designs. Computer scientists now take a different, innovative approach: their tool automatically creates 3D print templates for nanostructures for user-defined colors, and their structures do not follow any particular pattern.