Large tree visualization

Help
1

I have a tree of ~4M of nodes which I want to visualize, and I did it successfully with sfdp layout, but I want improvement. Nodes are too dense, they gravitate to center too much.

Below are visualizations of a tree which has 100K nodes, each with 4 children. Four main branches are colored. I’ve tried to make a tree more distributed by lowering K factor, but it increased branch overlapping as well. How to make readable as many branches as possible? Without overlapping, with sufficient space. In Gephi ForceAtlas2 I’d lowered Gravity value, but in sfdp I don’t see this param.

Since it’s a tree, maybe some preprocessing could help - e.g. computing a number of descendants for each node and using it as a parameter in visualization.

tree_20250829T122214683
tree_20250829T1222146831024×1024 205 KB

tree_20250829T123040249
tree_20250829T1230402491024×1024 281 KB

tree_20250829T123538073
tree_20250829T1235380731024×1024 256 KB

2

Non-graphviz people have worked specifically on large tree layout. I don’t know what’s state of the art in 2025, but this might be a starting point for a search: https://www.youtube.com/watch?v=aEgz4ca9FgU

Extra points just because Greg Humphreys was in an undergraduate system programming class I once taught in the … 1980s? wow.

3

It looks like interactive tool with folding/unfolding, while I’m interested in assigning x,y coordinates to each node. But I’m also trying to layout taxonomy tree: Full Tree of Life - Show and Tell - Graphviz