This layout is the Ploeg adaptation of the extended Reingold-Tilford algorithm as described in the paper van der Ploeg, A. (2014), Drawing non-layered tidy trees in linear time, Softw. Pract. Exper., 44, pages 1467– 1484, doi: 10.1002/spe.2213
The original implementation can be found on github at: non-layered-tidy-trees
This code is in the public domain, use it any way you wish. A reference to the paper is appreciated!
Non-layered tidy tree layout of a tree
Non-layered tidy tree layout of a forest
This implementation isolates the algorithm from the tree datastructure. The tree is obtained through via
List<V> Function() roots;
List<V> Function(V) next; Map<int, List<int>> simpleTree = {
0: [1, 2],
1: [3],
2: [4, 5],
3: [],
4: [],
5: []
};
Map<int, Offset> nodePositions = {};
Map<int, Size> nodeSizes = {};
var algo = PloegTreeLayout(
roots: () => [0],
next: (v) => simpleTree[v]!,
sizeGetter: (v) {
Size size =
Size(Random().nextInt(90) + 30, Random().nextInt(60) + 20);
nodeSizes[v] = size;
return size;
},
onPositionChange: (v, offset) => {nodePositions[v] = offset});
algo.layout();