cytoscape-tidytree/lib/src/alg/layout.js

Cytoscape.js layout extension for positioning trees

import { Tree } from "./tree.js";
export class Layout {
    options;
    constructor(options) {
        this.options = {
            horizontalSpacing: 10,
            verticalSpacing: 20,
            lineWidth: 3,
            layerHeight: undefined,
            ...options
        };
    }
    run(data) {
        const tree = this.makeTree(data, data.customY);
        tree.layout();
        this.setLayoutResult(data, tree);
        return tree;
    }
    makeTree(data, root_y = 0) {
        const outerWidth = data.w + this.options.horizontalSpacing;
        let outerHeight = data.h + this.options.verticalSpacing;
        let extraSpacing = data.extraVerticalSpacing ?? 0;
        const layerHeight = this.options.layerHeight;
        if (layerHeight !== undefined) {
            outerHeight = Math.ceil(outerHeight / layerHeight) * layerHeight;
            extraSpacing = Math.round(extraSpacing / layerHeight) * layerHeight;
        }
        if (data.customY !== undefined) {
            extraSpacing = data.customY - root_y;
            data.y = root_y + extraSpacing;
        }
        data.y = root_y + extraSpacing;
        const vertex = new Tree(outerWidth, outerHeight, data.y, data.children.map((child) => this.makeTree(child, data.y + outerHeight)));
        if (extraSpacing < 0) {
            console.warn("Node has negative extra space, ignoring", data);
        }
        if (extraSpacing > 0) {
            return new Tree(this.options.lineWidth, extraSpacing, root_y, [vertex], true);
        }
        return vertex;
    }
    setLayoutResult(data, tree) {
        if (tree.isExtra) {
            tree = tree.c[0];
        }
        data.x = tree.x + this.options.horizontalSpacing / 2;
        data.children.forEach((child, i) => this.setLayoutResult(child, tree.c[i]));
    }
}