-
Notifications
You must be signed in to change notification settings - Fork 5
/
springy.js
697 lines (580 loc) · 18.3 KB
/
springy.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
/**
* Springy v2.0.1
*
* Copyright (c) 2010 Dennis Hotson
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
(function() {
// Enable strict mode for EC5 compatible browsers
"use strict";
// Establish the root object, `window` in the browser, or `global` on the server.
var root = this;
// The top-level namespace. All public Springy classes and modules will
// be attached to this. Exported for both CommonJS and the browser.
var Springy;
if (typeof exports !== 'undefined') {
Springy = exports;
} else {
Springy = root.Springy = {};
}
var Graph = Springy.Graph = function() {
this.nodeSet = {};
this.nodes = [];
this.edges = [];
this.adjacency = {};
this.nextNodeId = 0;
this.nextEdgeId = 0;
this.eventListeners = [];
};
var Node = Springy.Node = function(id, data) {
this.id = id;
this.data = (data !== undefined) ? data : {};
// Data fields used by layout algorithm in this file:
// this.data.mass
// Data used by default renderer in springyui.js
// this.data.label
};
var Edge = Springy.Edge = function(id, source, target, data) {
this.id = id;
this.source = source;
this.target = target;
this.data = (data !== undefined) ? data : {};
// Edge data field used by layout alorithm
// this.data.length
// this.data.type
};
Graph.prototype.addNode = function(node) {
if (!(node.id in this.nodeSet)) {
this.nodes.push(node);
}
this.nodeSet[node.id] = node;
this.notify();
return node;
};
Graph.prototype.addNodes = function() {
// accepts variable number of arguments, where each argument
// is a string that becomes both node identifier and label
for (var i = 0; i < arguments.length; i++) {
var name = arguments[i];
var node = new Node(name, {label:name});
this.addNode(node);
}
};
Graph.prototype.addEdge = function(edge) {
var exists = false;
this.edges.forEach(function(e) {
if (edge.id === e.id) { exists = true; }
});
if (!exists) {
this.edges.push(edge);
}
if (!(edge.source.id in this.adjacency)) {
this.adjacency[edge.source.id] = {};
}
if (!(edge.target.id in this.adjacency[edge.source.id])) {
this.adjacency[edge.source.id][edge.target.id] = [];
}
exists = false;
this.adjacency[edge.source.id][edge.target.id].forEach(function(e) {
if (edge.id === e.id) { exists = true; }
});
if (!exists) {
this.adjacency[edge.source.id][edge.target.id].push(edge);
}
this.notify();
return edge;
};
Graph.prototype.addEdges = function() {
// accepts variable number of arguments, where each argument
// is a triple [nodeid1, nodeid2, attributes]
for (var i = 0; i < arguments.length; i++) {
var e = arguments[i];
var node1 = this.nodeSet[e[0]];
if (node1 == undefined) {
throw new TypeError("invalid node name: " + e[0]);
}
var node2 = this.nodeSet[e[1]];
if (node2 == undefined) {
throw new TypeError("invalid node name: " + e[1]);
}
var attr = e[2];
this.newEdge(node1, node2, attr);
}
};
Graph.prototype.newNode = function(data) {
var node = new Node(this.nextNodeId++, data);
this.addNode(node);
return node;
};
Graph.prototype.newEdge = function(source, target, data) {
var edge = new Edge(this.nextEdgeId++, source, target, data);
this.addEdge(edge);
return edge;
};
// add nodes and edges from JSON object
Graph.prototype.loadJSON = function(json) {
/**
Springy's simple JSON format for graphs.
historically, Springy uses separate lists
of nodes and edges:
{
"nodes": [
"center",
"left",
"right",
"up",
"satellite"
],
"edges": [
["center", "left"],
["center", "right"],
["center", "up"]
]
}
**/
// parse if a string is passed (EC5+ browsers)
if (typeof json == 'string' || json instanceof String) {
json = JSON.parse( json );
}
if ('nodes' in json || 'edges' in json) {
this.addNodes.apply(this, json['nodes']);
this.addEdges.apply(this, json['edges']);
}
}
// find the edges from node1 to node2
Graph.prototype.getEdges = function(node1, node2) {
if (node1.id in this.adjacency
&& node2.id in this.adjacency[node1.id]) {
return this.adjacency[node1.id][node2.id];
}
return [];
};
// remove a node and it's associated edges from the graph
Graph.prototype.removeNode = function(node) {
if (node.id in this.nodeSet) {
delete this.nodeSet[node.id];
}
for (var i = this.nodes.length - 1; i >= 0; i--) {
if (this.nodes[i].id === node.id) {
this.nodes.splice(i, 1);
}
}
this.detachNode(node);
};
// removes edges associated with a given node
Graph.prototype.detachNode = function(node) {
var tmpEdges = this.edges.slice();
tmpEdges.forEach(function(e) {
if (e.source.id === node.id || e.target.id === node.id) {
this.removeEdge(e);
}
}, this);
this.notify();
};
// remove a node and it's associated edges from the graph
Graph.prototype.removeEdge = function(edge) {
for (var i = this.edges.length - 1; i >= 0; i--) {
if (this.edges[i].id === edge.id) {
this.edges.splice(i, 1);
}
}
for (var x in this.adjacency) {
for (var y in this.adjacency[x]) {
var edges = this.adjacency[x][y];
for (var j=edges.length - 1; j>=0; j--) {
if (this.adjacency[x][y][j].id === edge.id) {
this.adjacency[x][y].splice(j, 1);
}
}
// Clean up empty edge arrays
if (this.adjacency[x][y].length == 0) {
delete this.adjacency[x][y];
}
}
// Clean up empty objects
if (isEmpty(this.adjacency[x])) {
delete this.adjacency[x];
}
}
this.notify();
};
/* Merge a list of nodes and edges into the current graph. eg.
var o = {
nodes: [
{id: 123, data: {type: 'user', userid: 123, displayname: 'aaa'}},
{id: 234, data: {type: 'user', userid: 234, displayname: 'bbb'}}
],
edges: [
{from: 0, to: 1, type: 'submitted_design', directed: true, data: {weight: }}
]
}
*/
Graph.prototype.merge = function(data) {
var nodes = [];
data.nodes.forEach(function(n) {
nodes.push(this.addNode(new Node(n.id, n.data)));
}, this);
data.edges.forEach(function(e) {
var from = nodes[e.from];
var to = nodes[e.to];
var id = (e.directed)
? (id = e.type + "-" + from.id + "-" + to.id)
: (from.id < to.id) // normalise id for non-directed edges
? e.type + "-" + from.id + "-" + to.id
: e.type + "-" + to.id + "-" + from.id;
var edge = this.addEdge(new Edge(id, from, to, e.data));
edge.data.type = e.type;
}, this);
};
Graph.prototype.filterNodes = function(fn) {
var tmpNodes = this.nodes.slice();
tmpNodes.forEach(function(n) {
if (!fn(n)) {
this.removeNode(n);
}
}, this);
};
Graph.prototype.filterEdges = function(fn) {
var tmpEdges = this.edges.slice();
tmpEdges.forEach(function(e) {
if (!fn(e)) {
this.removeEdge(e);
}
}, this);
};
Graph.prototype.addGraphListener = function(obj) {
this.eventListeners.push(obj);
};
Graph.prototype.notify = function() {
this.eventListeners.forEach(function(obj){
obj.graphChanged();
});
};
// -----------
var Layout = Springy.Layout = {};
Layout.ForceDirected = function(graph, stiffness, repulsion, damping) {
this.graph = graph;
this.stiffness = stiffness; // spring stiffness constant
this.repulsion = repulsion; // repulsion constant
this.damping = damping; // velocity damping factor
this.nodePoints = {}; // keep track of points associated with nodes
this.edgeSprings = {}; // keep track of springs associated with edges
};
Layout.ForceDirected.prototype.point = function(node) {
if (!(node.id in this.nodePoints)) {
var mass = (node.data.mass !== undefined) ? node.data.mass : 1.0;
this.nodePoints[node.id] = new Layout.ForceDirected.Point(Vector.random(), mass);
}
return this.nodePoints[node.id];
};
Layout.ForceDirected.prototype.spring = function(edge) {
if (!(edge.id in this.edgeSprings)) {
var length = (edge.data.length !== undefined) ? edge.data.length : 1.0;
var existingSpring = false;
var from = this.graph.getEdges(edge.source, edge.target);
from.forEach(function(e) {
if (existingSpring === false && e.id in this.edgeSprings) {
existingSpring = this.edgeSprings[e.id];
}
}, this);
if (existingSpring !== false) {
return new Layout.ForceDirected.Spring(existingSpring.point1, existingSpring.point2, 0.0, 0.0);
}
var to = this.graph.getEdges(edge.target, edge.source);
from.forEach(function(e){
if (existingSpring === false && e.id in this.edgeSprings) {
existingSpring = this.edgeSprings[e.id];
}
}, this);
if (existingSpring !== false) {
return new Layout.ForceDirected.Spring(existingSpring.point2, existingSpring.point1, 0.0, 0.0);
}
this.edgeSprings[edge.id] = new Layout.ForceDirected.Spring(
this.point(edge.source), this.point(edge.target), length, this.stiffness
);
}
return this.edgeSprings[edge.id];
};
// callback should accept two arguments: Node, Point
Layout.ForceDirected.prototype.eachNode = function(callback) {
var t = this;
this.graph.nodes.forEach(function(n){
callback.call(t, n, t.point(n));
});
};
// callback should accept two arguments: Edge, Spring
Layout.ForceDirected.prototype.eachEdge = function(callback) {
var t = this;
this.graph.edges.forEach(function(e){
callback.call(t, e, t.spring(e));
});
};
// callback should accept one argument: Spring
Layout.ForceDirected.prototype.eachSpring = function(callback) {
var t = this;
this.graph.edges.forEach(function(e){
callback.call(t, t.spring(e));
});
};
// Physics stuff
Layout.ForceDirected.prototype.applyCoulombsLaw = function() {
this.eachNode(function(n1, point1) {
this.eachNode(function(n2, point2) {
if (point1 !== point2)
{
var d = point1.p.subtract(point2.p);
var distance = d.magnitude() + 0.1; // avoid massive forces at small distances (and divide by zero)
var direction = d.normalise();
// apply force to each end point
point1.applyForce(direction.multiply(this.repulsion).divide(distance * distance * 0.5));
point2.applyForce(direction.multiply(this.repulsion).divide(distance * distance * -0.5));
}
});
});
};
Layout.ForceDirected.prototype.applyHookesLaw = function() {
this.eachSpring(function(spring){
var d = spring.point2.p.subtract(spring.point1.p); // the direction of the spring
var displacement = spring.length - d.magnitude();
var direction = d.normalise();
// apply force to each end point
spring.point1.applyForce(direction.multiply(spring.k * displacement * -0.5));
spring.point2.applyForce(direction.multiply(spring.k * displacement * 0.5));
});
};
Layout.ForceDirected.prototype.attractToCentre = function() {
this.eachNode(function(node, point) {
var direction = point.p.multiply(-1.0);
point.applyForce(direction.multiply(this.repulsion / 50.0));
});
};
Layout.ForceDirected.prototype.updateVelocity = function(timestep) {
this.eachNode(function(node, point) {
// Is this, along with updatePosition below, the only places that your
// integration code exist?
point.v = point.v.add(point.a.multiply(timestep)).multiply(this.damping);
point.a = new Vector(0,0);
});
};
Layout.ForceDirected.prototype.updatePosition = function(timestep) {
this.eachNode(function(node, point) {
// Same question as above; along with updateVelocity, is this all of
// your integration code?
point.p = point.p.add(point.v.multiply(timestep));
});
};
// Calculate the total kinetic energy of the system
Layout.ForceDirected.prototype.totalEnergy = function(timestep) {
var energy = 0.0;
this.eachNode(function(node, point) {
var speed = point.v.magnitude();
energy += 0.5 * point.m * speed * speed;
});
return energy;
};
var __bind = function(fn, me){ return function(){ return fn.apply(me, arguments); }; }; // stolen from coffeescript, thanks jashkenas! ;-)
Springy.requestAnimationFrame = __bind(root.requestAnimationFrame ||
root.webkitRequestAnimationFrame ||
root.mozRequestAnimationFrame ||
root.oRequestAnimationFrame ||
root.msRequestAnimationFrame ||
(function(callback, element) {
root.setTimeout(callback, 10);
}), root);
// start simulation
Layout.ForceDirected.prototype.start = function(render, done) {
var t = this;
if (this._started) return;
this._started = true;
this._stop = false;
Springy.requestAnimationFrame(function step() {
t.applyCoulombsLaw();
t.applyHookesLaw();
t.attractToCentre();
t.updateVelocity(0.03);
t.updatePosition(0.03);
if (render !== undefined) {
render();
}
// stop simulation when energy of the system goes below a threshold
if (t._stop || t.totalEnergy() < 0.01) {
t._started = false;
if (done !== undefined) { done(); }
} else {
Springy.requestAnimationFrame(step);
}
});
};
Layout.ForceDirected.prototype.stop = function() {
this._stop = true;
}
// Find the nearest point to a particular position
Layout.ForceDirected.prototype.nearest = function(pos) {
var min = {node: null, point: null, distance: null};
var t = this;
this.graph.nodes.forEach(function(n){
var point = t.point(n);
var distance = point.p.subtract(pos).magnitude();
if (min.distance === null || distance < min.distance) {
min = {node: n, point: point, distance: distance};
}
});
return min;
};
// returns [bottomleft, topright]
Layout.ForceDirected.prototype.getBoundingBox = function() {
var bottomleft = new Vector(-2,-2);
var topright = new Vector(2,2);
this.eachNode(function(n, point) {
if (point.p.x < bottomleft.x) {
bottomleft.x = point.p.x;
}
if (point.p.y < bottomleft.y) {
bottomleft.y = point.p.y;
}
if (point.p.x > topright.x) {
topright.x = point.p.x;
}
if (point.p.y > topright.y) {
topright.y = point.p.y;
}
});
var padding = topright.subtract(bottomleft).multiply(0.07); // ~5% padding
return {bottomleft: bottomleft.subtract(padding), topright: topright.add(padding)};
};
// Vector
var Vector = Springy.Vector = function(x, y) {
this.x = x;
this.y = y;
};
Vector.random = function() {
return new Vector(10.0 * (Math.random() - 0.5), 10.0 * (Math.random() - 0.5));
};
Vector.prototype.add = function(v2) {
return new Vector(this.x + v2.x, this.y + v2.y);
};
Vector.prototype.subtract = function(v2) {
return new Vector(this.x - v2.x, this.y - v2.y);
};
Vector.prototype.multiply = function(n) {
return new Vector(this.x * n, this.y * n);
};
Vector.prototype.divide = function(n) {
return new Vector((this.x / n) || 0, (this.y / n) || 0); // Avoid divide by zero errors..
};
Vector.prototype.magnitude = function() {
return Math.sqrt(this.x*this.x + this.y*this.y);
};
Vector.prototype.normal = function() {
return new Vector(-this.y, this.x);
};
Vector.prototype.normalise = function() {
return this.divide(this.magnitude());
};
// Point
Layout.ForceDirected.Point = function(position, mass) {
this.p = position; // position
this.m = mass; // mass
this.v = new Vector(0, 0); // velocity
this.a = new Vector(0, 0); // acceleration
};
Layout.ForceDirected.Point.prototype.applyForce = function(force) {
this.a = this.a.add(force.divide(this.m));
};
// Spring
Layout.ForceDirected.Spring = function(point1, point2, length, k) {
this.point1 = point1;
this.point2 = point2;
this.length = length; // spring length at rest
this.k = k; // spring constant (See Hooke's law) .. how stiff the spring is
};
// Layout.ForceDirected.Spring.prototype.distanceToPoint = function(point)
// {
// // hardcore vector arithmetic.. ohh yeah!
// // .. see http://stackoverflow.com/questions/849211/shortest-distance-between-a-point-and-a-line-segment/865080#865080
// var n = this.point2.p.subtract(this.point1.p).normalise().normal();
// var ac = point.p.subtract(this.point1.p);
// return Math.abs(ac.x * n.x + ac.y * n.y);
// };
// Renderer handles the layout rendering loop
var Renderer = Springy.Renderer = function(layout, clear, drawEdge, drawNode) {
this.layout = layout;
this.clear = clear;
this.drawEdge = drawEdge;
this.drawNode = drawNode;
this.layout.graph.addGraphListener(this);
}
Renderer.prototype.graphChanged = function(e) {
this.start();
};
Renderer.prototype.start = function() {
var t = this;
this.layout.start(function render() {
t.clear();
t.layout.eachEdge(function(edge, spring) {
t.drawEdge(edge, spring.point1.p, spring.point2.p);
});
t.layout.eachNode(function(node, point) {
t.drawNode(node, point.p);
});
});
};
Renderer.prototype.stop = function() {
this.layout.stop();
};
// Array.forEach implementation for IE support..
//https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/forEach
if ( !Array.prototype.forEach ) {
Array.prototype.forEach = function( callback, thisArg ) {
var T, k;
if ( this == null ) {
throw new TypeError( " this is null or not defined" );
}
var O = Object(this);
var len = O.length >>> 0; // Hack to convert O.length to a UInt32
if ( {}.toString.call(callback) != "[object Function]" ) {
throw new TypeError( callback + " is not a function" );
}
if ( thisArg ) {
T = thisArg;
}
k = 0;
while( k < len ) {
var kValue;
if ( k in O ) {
kValue = O[ k ];
callback.call( T, kValue, k, O );
}
k++;
}
};
}
var isEmpty = function(obj) {
for (var k in obj) {
if (obj.hasOwnProperty(k)) {
return false;
}
}
return true;
};
}).call(this);