“…Such contours share the characteristics of set diagrams such as Euler diagrams. Contour shapes are versatile, for instance, rectangles [DGC*05, DHRMM13, HRD10, YDG*15] (Figures b.2 and b.3), circle sections [ET07] or circles [Hol06, KG06, NIS15] (Figure b.1), convex hulls [BPF14, ST08, WWY*15], arbitrary two‐dimensional curves or splines [BBT06, BD05, BT06, BT09b, DEKB*14, DvKSW12, EHKP14, GHK10, HGK10, HKV14, LQB12, VPF*14] (Figure c), or three‐dimensional bubbles [BD07, SBG00]. The GMap approach [GHK10, HGK10, HKV14] creates a map of contours that are adjacent to each other using a Voronoi tessellation.…”