Convex treemap Sometimes also called ：( Voronoi treemap, Polygonal partition )
Similar to a regular square treemap, but convex polygons are used instead of rectangles e.g. a new hierarchical partition scheme, also called a polygonal partition, which uses convex polygons rather than just rectangles.
Treemaps display hierarchical (tree-structured) data as a set of nested polygons. Each branch of the tree is given a polygons, which is then tiled with smaller polygons representing sub-branches.
The use of Convex Treemaps compared to regular tree maps would be when you want to show grouping and realtions instead of the strict hierachical structure of a a normal treemap.