  We introduce a framework for the generation of grid-shell structures that is
based on Voronoi diagrams and allows us to design tessellations that achieve
excellent static performances. We start from an analysis of stress on the input
surface and we use the resulting tensor field to induce an anisotropic
non-Euclidean metric over it. Then we compute a Centroidal Voronoi Tessellation
under the same metric. The resulting mesh is hex-dominant and made of cells
with a variable density, which depends on the amount of stress, and anisotropic
shape, which depends on the direction of maximum stress. This mesh is further
optimized taking into account symmetry and regularity of cells to improve
aesthetics. We demonstrate that our grid-shells achieve better static
performances with respect to quad-based grid shells, while offering an
innovative and aesthetically pleasing look.
