Hi Terence, thanks for sharing this! You may be aware already, but I just want to point out that treemapify includes a layout algorithm called 'fixed' which is intended for use with animated treemaps. It places the tiles deterministically, such that if the same set of tiles is used for each frame of the treemap (which means including tiles with an area value of 0), they will appear in the same location in each frame. The downside is that the layout is less aesthetically pleasing than the squarified layout, and smaller tiles may be harder to appreciate.