gojs
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Interactive diagrams, charts, and graphs, such as trees, flowcharts, orgcharts, UML, BPMN, or business diagrams
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JavaScript
/*
* Copyright (C) 1998-2020 by Northwoods Software Corporation. All Rights Reserved.
*/
/*
* This is an extension and not part of the main GoJS library.
* Note that the API for this class may change with any version, even point releases.
* If you intend to use an extension in production, you should copy the code to your own source directory.
* Extensions can be found in the GoJS kit under the extensions or extensionsTS folders.
* See the Extensions intro page (https://gojs.net/latest/intro/extensions.html) for more information.
*/
import * as go from '../release/go-module.js';
/**
* Given a root {@link Node}, this arranges connected nodes in concentric rings,
* layered by the minimum link distance from the root.
*
* If you want to experiment with this extension, try the <a href="../../extensionsTS/Radial.html">Radial Layout</a> sample.
* @category Layout Extension
*/
export class RadialLayout extends go.Layout {
constructor() {
super(...arguments);
this._root = null;
this._layerThickness = 100; // how thick each ring should be
this._maxLayers = Infinity;
}
/**
* Gets or sets the {@link Node} that acts as the root or central node of the radial layout.
*/
get root() { return this._root; }
set root(value) {
if (this._root !== value) {
this._root = value;
this.invalidateLayout();
}
}
/**
* Gets or sets the thickness of each ring representing a layer.
*
* The default value is 100.
*/
get layerThickness() { return this._layerThickness; }
set layerThickness(value) {
if (this._layerThickness !== value) {
this._layerThickness = value;
this.invalidateLayout();
}
}
/**
* Gets or sets the maximum number of layers to be shown, in addition to the root node at layer zero.
*
* The default value is Infinity.
*/
get maxLayers() { return this._maxLayers; }
set maxLayers(value) {
if (this._maxLayers !== value) {
this._maxLayers = value;
this.invalidateLayout();
}
}
/**
* Copies properties to a cloned Layout.
*/
cloneProtected(copy) {
super.cloneProtected(copy);
// don't copy .root
copy._layerThickness = this._layerThickness;
copy._maxLayers = this._maxLayers;
}
/**
* Use a LayoutNetwork that always creates RadialVertexes.
*/
createNetwork() {
const net = new go.LayoutNetwork(this);
net.createVertex = () => new RadialVertex(net);
return net;
}
/**
* Find distances between root and vertexes, and then lay out radially.
* @param {Diagram|Group|Iterable.<Part>} coll A {@link Diagram} or a {@link Group} or a collection of {@link Part}s.
*/
doLayout(coll) {
if (this.network === null) {
this.network = this.makeNetwork(coll);
}
if (this.network.vertexes.count === 0)
return;
if (this.root === null) {
// If no root supplied, choose one without any incoming edges
const rit = this.network.vertexes.iterator;
while (rit.next()) {
const v = rit.value;
if (v.node !== null && v.sourceEdges.count === 0) {
this.root = v.node;
break;
}
}
}
if (this.root === null && this.network !== null) {
// If could not find any default root, choose a random one
const first = this.network.vertexes.first();
this.root = first === null ? null : first.node;
}
if (this.root === null)
return; // nothing to do
const rootvert = this.network.findVertex(this.root);
if (rootvert === null)
throw new Error('RadialLayout.root must be a Node in the LayoutNetwork that the RadialLayout is operating on');
this.arrangementOrigin = this.initialOrigin(this.arrangementOrigin);
this.findDistances(rootvert);
// sort all results into Arrays of RadialVertexes with the same distance
const verts = [];
let maxlayer = 0;
const it = this.network.vertexes.iterator;
while (it.next()) {
const vv = it.value;
vv.laid = false;
const layer = vv.distance;
if (layer === Infinity)
continue; // Infinity used as init value (set in findDistances())
if (layer > maxlayer)
maxlayer = layer;
let layerverts = verts[layer];
if (layerverts === undefined) {
layerverts = [];
verts[layer] = layerverts;
}
layerverts.push(vv);
}
// now recursively position nodes (using radlay1()), starting with the root
rootvert.centerX = this.arrangementOrigin.x;
rootvert.centerY = this.arrangementOrigin.y;
this.radlay1(rootvert, 1, 0, 360);
// Update the "physical" positions of the nodes and links.
this.updateParts();
this.network = null;
}
/**
* Recursively position vertexes in a radial layout
*/
radlay1(vert, layer, angle, sweep) {
if (layer > this.maxLayers)
return; // no need to position nodes outside of maxLayers
const verts = []; // array of all RadialVertexes connected to 'vert' in layer 'layer'
const vit = vert.vertexes.iterator;
while (vit.next()) {
const v = vit.value;
if (v.laid)
continue;
if (v.distance === layer)
verts.push(v);
}
// vert.vertexes.each((v: go.LayoutVertex) => {
// if (!(v instanceof RadialVertex)) return; // typeguard
// if (v.laid) return;
// if (v.distance === layer) verts.push(v);
// });
const found = verts.length;
if (found === 0)
return;
const radius = layer * this.layerThickness;
const separator = sweep / found; // distance between nodes in their sweep portion
const start = angle - sweep / 2 + separator / 2;
// for each vertex in this layer, place it in its correct layer and position
for (let i = 0; i < found; i++) {
const v = verts[i];
let a = start + i * separator; // the angle to rotate the node to
if (a < 0)
a += 360;
else if (a > 360)
a -= 360;
// the point to place the node at -- this corresponds with the layer the node is in
// all nodes in the same layer are placed at a constant point, then rotated accordingly
const p = new go.Point(radius, 0);
p.rotate(a);
v.centerX = p.x + this.arrangementOrigin.x;
v.centerY = p.y + this.arrangementOrigin.y;
v.laid = true;
v.angle = a;
v.sweep = separator;
v.radius = radius;
// keep going for all layers
this.radlay1(v, layer + 1, a, sweep / found);
}
}
/**
* Update RadialVertex.distance for every vertex.
*/
findDistances(source) {
if (this.network === null)
return;
// keep track of distances from the source node
const vit = this.network.vertexes.iterator;
while (vit.next()) {
const v = vit.value;
v.distance = Infinity;
}
// this.network.vertexes.each((v: go.LayoutVertex) => {
// if (!(v instanceof RadialVertex)) return; // typeguard
// v.distance = Infinity;
// });
// the source node starts with distance 0
source.distance = 0;
// keep track of nodes for we have set a non-Infinity distance,
// but which we have not yet finished examining
const seen = new go.Set();
seen.add(source);
// local function for finding a vertex with the smallest distance in a given collection
function leastVertex(coll) {
let bestdist = Infinity;
let bestvert = null;
const it = coll.iterator;
while (it.next()) {
const v = it.value;
const dist = v.distance;
if (dist < bestdist) {
bestdist = dist;
bestvert = v;
}
}
return bestvert;
}
// keep track of vertexes we have finished examining;
// this avoids unnecessary traversals and helps keep the SEEN collection small
const finished = new go.Set();
while (seen.count > 0) {
// look at the unfinished vertex with the shortest distance so far
const least = leastVertex(seen);
if (least === null)
return;
const leastdist = least.distance;
// by the end of this loop we will have finished examining this LEAST vertex
seen.remove(least);
finished.add(least);
// look at all edges connected with this vertex
least.edges.each(function (e) {
if (least === null)
return;
const neighbor = e.getOtherVertex(least);
// skip vertexes that we have finished
if (finished.contains(neighbor))
return;
const neighbordist = neighbor.distance;
// assume "distance" along a link is unitary, but could be any non-negative number.
const dist = leastdist + 1;
if (dist < neighbordist) {
// if haven't seen that vertex before, add it to the SEEN collection
if (neighbordist === Infinity) {
seen.add(neighbor);
}
// record the new best distance so far to that node
neighbor.distance = dist;
}
});
}
}
/**
* This override positions each Node and also calls {@link #rotateNode}.
*/
commitLayout() {
super.commitLayout();
if (this.network !== null) {
const it = this.network.vertexes.iterator;
while (it.next()) {
const v = it.value;
const n = v.node;
if (n !== null) {
n.visible = (v.distance <= this.maxLayers);
this.rotateNode(n, v.angle, v.sweep, v.radius);
}
}
}
this.commitLayers();
}
/**
* Override this method in order to modify each node as it is laid out.
* By default this method does nothing.
* @expose
*/
rotateNode(node, angle, sweep, radius) { }
/**
* Override this method in order to create background circles indicating the layers of the radial layout.
* By default this method does nothing.
* @expose
*/
commitLayers() { }
} // end RadialLayout
/**
* RadialVertex, a LayoutVertex that holds additional info
*/
class RadialVertex extends go.LayoutVertex {
constructor(network) {
super(network);
this.distance = Infinity; // number of layers from the root, non-negative integers
this.laid = false; // used internally to keep track
this.angle = 0; // the direction at which the node is placed relative to the root node
this.sweep = 0; // the angle subtended by the vertex
this.radius = 0; // the inner radius of the layer containing this vertex
}
}