† Joint first authors (a) (b) (c) (d) Figure 1: Closed space-filling curves optimized under (a) anisotropy, (b) boundary alignment (c) isotropy inside the E and boundary alignment inside the G. Isotropy and anisotropy are optimized in terms of distribution of angles, while alignment is specified in a vector field (here parallel to the boundary). For the three curves, the number of transitions between the two letters of the logo is minimized. (d) Multi-material 3D printed cube, with isotropic layers optimized by our approach.