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Force Dragging III
Raw
.block
license: gpl-3.0
height: 600
Raw
README.md

This example demonstrates applying d3-drag to a force-directed graph computed using d3-force. When the drag gesture starts, the targeted node is fixed to the pointer; it is released when the gesture ends. In addition, the simulation is temporarily “heated” during interaction by setting the target alpha to a non-zero value.

Compare to the SVG version.

Raw
index.html
<!DOCTYPE html>
<meta charset="utf-8">
<canvas width="960" height="600"></canvas>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
var canvas = document.querySelector("canvas"),
context = canvas.getContext("2d"),
width = canvas.width,
height = canvas.height;
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(width / 2, height / 2));
d3.json("miserables.json", function(error, graph) {
if (error) throw error;
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
d3.select(canvas)
.call(d3.drag()
.container(canvas)
.subject(dragsubject)
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
function ticked() {
context.clearRect(0, 0, width, height);
context.beginPath();
graph.links.forEach(drawLink);
context.strokeStyle = "#aaa";
context.stroke();
context.beginPath();
graph.nodes.forEach(drawNode);
context.fill();
context.strokeStyle = "#fff";
context.stroke();
}
function dragsubject() {
return simulation.find(d3.event.x, d3.event.y);
}
});
function dragstarted() {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d3.event.subject.fx = d3.event.subject.x;
d3.event.subject.fy = d3.event.subject.y;
}
function dragged() {
d3.event.subject.fx = d3.event.x;
d3.event.subject.fy = d3.event.y;
}
function dragended() {
if (!d3.event.active) simulation.alphaTarget(0);
d3.event.subject.fx = null;
d3.event.subject.fy = null;
}
function drawLink(d) {
context.moveTo(d.source.x, d.source.y);
context.lineTo(d.target.x, d.target.y);
}
function drawNode(d) {
context.moveTo(d.x + 3, d.y);
context.arc(d.x, d.y, 3, 0, 2 * Math.PI);
}
</script>
Raw
miserables.json
{
"nodes": [
{"id": "Myriel", "group": 1},
{"id": "Napoleon", "group": 1},
{"id": "Mlle.Baptistine", "group": 1},
{"id": "Mme.Magloire", "group": 1},
{"id": "CountessdeLo", "group": 1},
{"id": "Geborand", "group": 1},
{"id": "Champtercier", "group": 1},
{"id": "Cravatte", "group": 1},
{"id": "Count", "group": 1},
{"id": "OldMan", "group": 1},
{"id": "Labarre", "group": 2},
{"id": "Valjean", "group": 2},
{"id": "Marguerite", "group": 3},
{"id": "Mme.deR", "group": 2},
{"id": "Isabeau", "group": 2},
{"id": "Gervais", "group": 2},
{"id": "Tholomyes", "group": 3},
{"id": "Listolier", "group": 3},
{"id": "Fameuil", "group": 3},
{"id": "Blacheville", "group": 3},
{"id": "Favourite", "group": 3},
{"id": "Dahlia", "group": 3},
{"id": "Zephine", "group": 3},
{"id": "Fantine", "group": 3},
{"id": "Mme.Thenardier", "group": 4},
{"id": "Thenardier", "group": 4},
{"id": "Cosette", "group": 5},
{"id": "Javert", "group": 4},
{"id": "Fauchelevent", "group": 0},
{"id": "Bamatabois", "group": 2},
{"id": "Perpetue", "group": 3},
{"id": "Simplice", "group": 2},
{"id": "Scaufflaire", "group": 2},
{"id": "Woman1", "group": 2},
{"id": "Judge", "group": 2},
{"id": "Champmathieu", "group": 2},
{"id": "Brevet", "group": 2},
{"id": "Chenildieu", "group": 2},
{"id": "Cochepaille", "group": 2},
{"id": "Pontmercy", "group": 4},
{"id": "Boulatruelle", "group": 6},
{"id": "Eponine", "group": 4},
{"id": "Anzelma", "group": 4},
{"id": "Woman2", "group": 5},
{"id": "MotherInnocent", "group": 0},
{"id": "Gribier", "group": 0},
{"id": "Jondrette", "group": 7},
{"id": "Mme.Burgon", "group": 7},
{"id": "Gavroche", "group": 8},
{"id": "Gillenormand", "group": 5},
{"id": "Magnon", "group": 5},
{"id": "Mlle.Gillenormand", "group": 5},
{"id": "Mme.Pontmercy", "group": 5},
{"id": "Mlle.Vaubois", "group": 5},
{"id": "Lt.Gillenormand", "group": 5},
{"id": "Marius", "group": 8},
{"id": "BaronessT", "group": 5},
{"id": "Mabeuf", "group": 8},
{"id": "Enjolras", "group": 8},
{"id": "Combeferre", "group": 8},
{"id": "Prouvaire", "group": 8},
{"id": "Feuilly", "group": 8},
{"id": "Courfeyrac", "group": 8},
{"id": "Bahorel", "group": 8},
{"id": "Bossuet", "group": 8},
{"id": "Joly", "group": 8},
{"id": "Grantaire", "group": 8},
{"id": "MotherPlutarch", "group": 9},
{"id": "Gueulemer", "group": 4},
{"id": "Babet", "group": 4},
{"id": "Claquesous", "group": 4},
{"id": "Montparnasse", "group": 4},
{"id": "Toussaint", "group": 5},
{"id": "Child1", "group": 10},
{"id": "Child2", "group": 10},
{"id": "Brujon", "group": 4},
{"id": "Mme.Hucheloup", "group": 8}
],
"links": [
{"source": "Napoleon", "target": "Myriel", "value": 1},
{"source": "Mlle.Baptistine", "target": "Myriel", "value": 8},
{"source": "Mme.Magloire", "target": "Myriel", "value": 10},
{"source": "Mme.Magloire", "target": "Mlle.Baptistine", "value": 6},
{"source": "CountessdeLo", "target": "Myriel", "value": 1},
{"source": "Geborand", "target": "Myriel", "value": 1},
{"source": "Champtercier", "target": "Myriel", "value": 1},
{"source": "Cravatte", "target": "Myriel", "value": 1},
{"source": "Count", "target": "Myriel", "value": 2},
{"source": "OldMan", "target": "Myriel", "value": 1},
{"source": "Valjean", "target": "Labarre", "value": 1},
{"source": "Valjean", "target": "Mme.Magloire", "value": 3},
{"source": "Valjean", "target": "Mlle.Baptistine", "value": 3},
{"source": "Valjean", "target": "Myriel", "value": 5},
{"source": "Marguerite", "target": "Valjean", "value": 1},
{"source": "Mme.deR", "target": "Valjean", "value": 1},
{"source": "Isabeau", "target": "Valjean", "value": 1},
{"source": "Gervais", "target": "Valjean", "value": 1},
{"source": "Listolier", "target": "Tholomyes", "value": 4},
{"source": "Fameuil", "target": "Tholomyes", "value": 4},
{"source": "Fameuil", "target": "Listolier", "value": 4},
{"source": "Blacheville", "target": "Tholomyes", "value": 4},
{"source": "Blacheville", "target": "Listolier", "value": 4},
{"source": "Blacheville", "target": "Fameuil", "value": 4},
{"source": "Favourite", "target": "Tholomyes", "value": 3},
{"source": "Favourite", "target": "Listolier", "value": 3},
{"source": "Favourite", "target": "Fameuil", "value": 3},
{"source": "Favourite", "target": "Blacheville", "value": 4},
{"source": "Dahlia", "target": "Tholomyes", "value": 3},
{"source": "Dahlia", "target": "Listolier", "value": 3},
{"source": "Dahlia", "target": "Fameuil", "value": 3},
{"source": "Dahlia", "target": "Blacheville", "value": 3},
{"source": "Dahlia", "target": "Favourite", "value": 5},
{"source": "Zephine", "target": "Tholomyes", "value": 3},
{"source": "Zephine", "target": "Listolier", "value": 3},
{"source": "Zephine", "target": "Fameuil", "value": 3},
{"source": "Zephine", "target": "Blacheville", "value": 3},
{"source": "Zephine", "target": "Favourite", "value": 4},
{"source": "Zephine", "target": "Dahlia", "value": 4},
{"source": "Fantine", "target": "Tholomyes", "value": 3},
{"source": "Fantine", "target": "Listolier", "value": 3},
{"source": "Fantine", "target": "Fameuil", "value": 3},
{"source": "Fantine", "target": "Blacheville", "value": 3},
{"source": "Fantine", "target": "Favourite", "value": 4},
{"source": "Fantine", "target": "Dahlia", "value": 4},
{"source": "Fantine", "target": "Zephine", "value": 4},
{"source": "Fantine", "target": "Marguerite", "value": 2},
{"source": "Fantine", "target": "Valjean", "value": 9},
{"source": "Mme.Thenardier", "target": "Fantine", "value": 2},
{"source": "Mme.Thenardier", "target": "Valjean", "value": 7},
{"source": "Thenardier", "target": "Mme.Thenardier", "value": 13},
{"source": "Thenardier", "target": "Fantine", "value": 1},
{"source": "Thenardier", "target": "Valjean", "value": 12},
{"source": "Cosette", "target": "Mme.Thenardier", "value": 4},
{"source": "Cosette", "target": "Valjean", "value": 31},
{"source": "Cosette", "target": "Tholomyes", "value": 1},
{"source": "Cosette", "target": "Thenardier", "value": 1},
{"source": "Javert", "target": "Valjean", "value": 17},
{"source": "Javert", "target": "Fantine", "value": 5},
{"source": "Javert", "target": "Thenardier", "value": 5},
{"source": "Javert", "target": "Mme.Thenardier", "value": 1},
{"source": "Javert", "target": "Cosette", "value": 1},
{"source": "Fauchelevent", "target": "Valjean", "value": 8},
{"source": "Fauchelevent", "target": "Javert", "value": 1},
{"source": "Bamatabois", "target": "Fantine", "value": 1},
{"source": "Bamatabois", "target": "Javert", "value": 1},
{"source": "Bamatabois", "target": "Valjean", "value": 2},
{"source": "Perpetue", "target": "Fantine", "value": 1},
{"source": "Simplice", "target": "Perpetue", "value": 2},
{"source": "Simplice", "target": "Valjean", "value": 3},
{"source": "Simplice", "target": "Fantine", "value": 2},
{"source": "Simplice", "target": "Javert", "value": 1},
{"source": "Scaufflaire", "target": "Valjean", "value": 1},
{"source": "Woman1", "target": "Valjean", "value": 2},
{"source": "Woman1", "target": "Javert", "value": 1},
{"source": "Judge", "target": "Valjean", "value": 3},
{"source": "Judge", "target": "Bamatabois", "value": 2},
{"source": "Champmathieu", "target": "Valjean", "value": 3},
{"source": "Champmathieu", "target": "Judge", "value": 3},
{"source": "Champmathieu", "target": "Bamatabois", "value": 2},
{"source": "Brevet", "target": "Judge", "value": 2},
{"source": "Brevet", "target": "Champmathieu", "value": 2},
{"source": "Brevet", "target": "Valjean", "value": 2},
{"source": "Brevet", "target": "Bamatabois", "value": 1},
{"source": "Chenildieu", "target": "Judge", "value": 2},
{"source": "Chenildieu", "target": "Champmathieu", "value": 2},
{"source": "Chenildieu", "target": "Brevet", "value": 2},
{"source": "Chenildieu", "target": "Valjean", "value": 2},
{"source": "Chenildieu", "target": "Bamatabois", "value": 1},
{"source": "Cochepaille", "target": "Judge", "value": 2},
{"source": "Cochepaille", "target": "Champmathieu", "value": 2},
{"source": "Cochepaille", "target": "Brevet", "value": 2},
{"source": "Cochepaille", "target": "Chenildieu", "value": 2},
{"source": "Cochepaille", "target": "Valjean", "value": 2},
{"source": "Cochepaille", "target": "Bamatabois", "value": 1},
{"source": "Pontmercy", "target": "Thenardier", "value": 1},
{"source": "Boulatruelle", "target": "Thenardier", "value": 1},
{"source": "Eponine", "target": "Mme.Thenardier", "value": 2},
{"source": "Eponine", "target": "Thenardier", "value": 3},
{"source": "Anzelma", "target": "Eponine", "value": 2},
{"source": "Anzelma", "target": "Thenardier", "value": 2},
{"source": "Anzelma", "target": "Mme.Thenardier", "value": 1},
{"source": "Woman2", "target": "Valjean", "value": 3},
{"source": "Woman2", "target": "Cosette", "value": 1},
{"source": "Woman2", "target": "Javert", "value": 1},
{"source": "MotherInnocent", "target": "Fauchelevent", "value": 3},
{"source": "MotherInnocent", "target": "Valjean", "value": 1},
{"source": "Gribier", "target": "Fauchelevent", "value": 2},
{"source": "Mme.Burgon", "target": "Jondrette", "value": 1},
{"source": "Gavroche", "target": "Mme.Burgon", "value": 2},
{"source": "Gavroche", "target": "Thenardier", "value": 1},
{"source": "Gavroche", "target": "Javert", "value": 1},
{"source": "Gavroche", "target": "Valjean", "value": 1},
{"source": "Gillenormand", "target": "Cosette", "value": 3},
{"source": "Gillenormand", "target": "Valjean", "value": 2},
{"source": "Magnon", "target": "Gillenormand", "value": 1},
{"source": "Magnon", "target": "Mme.Thenardier", "value": 1},
{"source": "Mlle.Gillenormand", "target": "Gillenormand", "value": 9},
{"source": "Mlle.Gillenormand", "target": "Cosette", "value": 2},
{"source": "Mlle.Gillenormand", "target": "Valjean", "value": 2},
{"source": "Mme.Pontmercy", "target": "Mlle.Gillenormand", "value": 1},
{"source": "Mme.Pontmercy", "target": "Pontmercy", "value": 1},
{"source": "Mlle.Vaubois", "target": "Mlle.Gillenormand", "value": 1},
{"source": "Lt.Gillenormand", "target": "Mlle.Gillenormand", "value": 2},
{"source": "Lt.Gillenormand", "target": "Gillenormand", "value": 1},
{"source": "Lt.Gillenormand", "target": "Cosette", "value": 1},
{"source": "Marius", "target": "Mlle.Gillenormand", "value": 6},
{"source": "Marius", "target": "Gillenormand", "value": 12},
{"source": "Marius", "target": "Pontmercy", "value": 1},
{"source": "Marius", "target": "Lt.Gillenormand", "value": 1},
{"source": "Marius", "target": "Cosette", "value": 21},
{"source": "Marius", "target": "Valjean", "value": 19},
{"source": "Marius", "target": "Tholomyes", "value": 1},
{"source": "Marius", "target": "Thenardier", "value": 2},
{"source": "Marius", "target": "Eponine", "value": 5},
{"source": "Marius", "target": "Gavroche", "value": 4},
{"source": "BaronessT", "target": "Gillenormand", "value": 1},
{"source": "BaronessT", "target": "Marius", "value": 1},
{"source": "Mabeuf", "target": "Marius", "value": 1},
{"source": "Mabeuf", "target": "Eponine", "value": 1},
{"source": "Mabeuf", "target": "Gavroche", "value": 1},
{"source": "Enjolras", "target": "Marius", "value": 7},
{"source": "Enjolras", "target": "Gavroche", "value": 7},
{"source": "Enjolras", "target": "Javert", "value": 6},
{"source": "Enjolras", "target": "Mabeuf", "value": 1},
{"source": "Enjolras", "target": "Valjean", "value": 4},
{"source": "Combeferre", "target": "Enjolras", "value": 15},
{"source": "Combeferre", "target": "Marius", "value": 5},
{"source": "Combeferre", "target": "Gavroche", "value": 6},
{"source": "Combeferre", "target": "Mabeuf", "value": 2},
{"source": "Prouvaire", "target": "Gavroche", "value": 1},
{"source": "Prouvaire", "target": "Enjolras", "value": 4},
{"source": "Prouvaire", "target": "Combeferre", "value": 2},
{"source": "Feuilly", "target": "Gavroche", "value": 2},
{"source": "Feuilly", "target": "Enjolras", "value": 6},
{"source": "Feuilly", "target": "Prouvaire", "value": 2},
{"source": "Feuilly", "target": "Combeferre", "value": 5},
{"source": "Feuilly", "target": "Mabeuf", "value": 1},
{"source": "Feuilly", "target": "Marius", "value": 1},
{"source": "Courfeyrac", "target": "Marius", "value": 9},
{"source": "Courfeyrac", "target": "Enjolras", "value": 17},
{"source": "Courfeyrac", "target": "Combeferre", "value": 13},
{"source": "Courfeyrac", "target": "Gavroche", "value": 7},
{"source": "Courfeyrac", "target": "Mabeuf", "value": 2},
{"source": "Courfeyrac", "target": "Eponine", "value": 1},
{"source": "Courfeyrac", "target": "Feuilly", "value": 6},
{"source": "Courfeyrac", "target": "Prouvaire", "value": 3},
{"source": "Bahorel", "target": "Combeferre", "value": 5},
{"source": "Bahorel", "target": "Gavroche", "value": 5},
{"source": "Bahorel", "target": "Courfeyrac", "value": 6},
{"source": "Bahorel", "target": "Mabeuf", "value": 2},
{"source": "Bahorel", "target": "Enjolras", "value": 4},
{"source": "Bahorel", "target": "Feuilly", "value": 3},
{"source": "Bahorel", "target": "Prouvaire", "value": 2},
{"source": "Bahorel", "target": "Marius", "value": 1},
{"source": "Bossuet", "target": "Marius", "value": 5},
{"source": "Bossuet", "target": "Courfeyrac", "value": 12},
{"source": "Bossuet", "target": "Gavroche", "value": 5},
{"source": "Bossuet", "target": "Bahorel", "value": 4},
{"source": "Bossuet", "target": "Enjolras", "value": 10},
{"source": "Bossuet", "target": "Feuilly", "value": 6},
{"source": "Bossuet", "target": "Prouvaire", "value": 2},
{"source": "Bossuet", "target": "Combeferre", "value": 9},
{"source": "Bossuet", "target": "Mabeuf", "value": 1},
{"source": "Bossuet", "target": "Valjean", "value": 1},
{"source": "Joly", "target": "Bahorel", "value": 5},
{"source": "Joly", "target": "Bossuet", "value": 7},
{"source": "Joly", "target": "Gavroche", "value": 3},
{"source": "Joly", "target": "Courfeyrac", "value": 5},
{"source": "Joly", "target": "Enjolras", "value": 5},
{"source": "Joly", "target": "Feuilly", "value": 5},
{"source": "Joly", "target": "Prouvaire", "value": 2},
{"source": "Joly", "target": "Combeferre", "value": 5},
{"source": "Joly", "target": "Mabeuf", "value": 1},
{"source": "Joly", "target": "Marius", "value": 2},
{"source": "Grantaire", "target": "Bossuet", "value": 3},
{"source": "Grantaire", "target": "Enjolras", "value": 3},
{"source": "Grantaire", "target": "Combeferre", "value": 1},
{"source": "Grantaire", "target": "Courfeyrac", "value": 2},
{"source": "Grantaire", "target": "Joly", "value": 2},
{"source": "Grantaire", "target": "Gavroche", "value": 1},
{"source": "Grantaire", "target": "Bahorel", "value": 1},
{"source": "Grantaire", "target": "Feuilly", "value": 1},
{"source": "Grantaire", "target": "Prouvaire", "value": 1},
{"source": "MotherPlutarch", "target": "Mabeuf", "value": 3},
{"source": "Gueulemer", "target": "Thenardier", "value": 5},
{"source": "Gueulemer", "target": "Valjean", "value": 1},
{"source": "Gueulemer", "target": "Mme.Thenardier", "value": 1},
{"source": "Gueulemer", "target": "Javert", "value": 1},
{"source": "Gueulemer", "target": "Gavroche", "value": 1},
{"source": "Gueulemer", "target": "Eponine", "value": 1},
{"source": "Babet", "target": "Thenardier", "value": 6},
{"source": "Babet", "target": "Gueulemer", "value": 6},
{"source": "Babet", "target": "Valjean", "value": 1},
{"source": "Babet", "target": "Mme.Thenardier", "value": 1},
{"source": "Babet", "target": "Javert", "value": 2},
{"source": "Babet", "target": "Gavroche", "value": 1},
{"source": "Babet", "target": "Eponine", "value": 1},
{"source": "Claquesous", "target": "Thenardier", "value": 4},
{"source": "Claquesous", "target": "Babet", "value": 4},
{"source": "Claquesous", "target": "Gueulemer", "value": 4},
{"source": "Claquesous", "target": "Valjean", "value": 1},
{"source": "Claquesous", "target": "Mme.Thenardier", "value": 1},
{"source": "Claquesous", "target": "Javert", "value": 1},
{"source": "Claquesous", "target": "Eponine", "value": 1},
{"source": "Claquesous", "target": "Enjolras", "value": 1},
{"source": "Montparnasse", "target": "Javert", "value": 1},
{"source": "Montparnasse", "target": "Babet", "value": 2},
{"source": "Montparnasse", "target": "Gueulemer", "value": 2},
{"source": "Montparnasse", "target": "Claquesous", "value": 2},
{"source": "Montparnasse", "target": "Valjean", "value": 1},
{"source": "Montparnasse", "target": "Gavroche", "value": 1},
{"source": "Montparnasse", "target": "Eponine", "value": 1},
{"source": "Montparnasse", "target": "Thenardier", "value": 1},
{"source": "Toussaint", "target": "Cosette", "value": 2},
{"source": "Toussaint", "target": "Javert", "value": 1},
{"source": "Toussaint", "target": "Valjean", "value": 1},
{"source": "Child1", "target": "Gavroche", "value": 2},
{"source": "Child2", "target": "Gavroche", "value": 2},
{"source": "Child2", "target": "Child1", "value": 3},
{"source": "Brujon", "target": "Babet", "value": 3},
{"source": "Brujon", "target": "Gueulemer", "value": 3},
{"source": "Brujon", "target": "Thenardier", "value": 3},
{"source": "Brujon", "target": "Gavroche", "value": 1},
{"source": "Brujon", "target": "Eponine", "value": 1},
{"source": "Brujon", "target": "Claquesous", "value": 1},
{"source": "Brujon", "target": "Montparnasse", "value": 1},
{"source": "Mme.Hucheloup", "target": "Bossuet", "value": 1},
{"source": "Mme.Hucheloup", "target": "Joly", "value": 1},
{"source": "Mme.Hucheloup", "target": "Grantaire", "value": 1},
{"source": "Mme.Hucheloup", "target": "Bahorel", "value": 1},
{"source": "Mme.Hucheloup", "target": "Courfeyrac", "value": 1},
{"source": "Mme.Hucheloup", "target": "Gavroche", "value": 1},
{"source": "Mme.Hucheloup", "target": "Enjolras", "value": 1}
]
}
@Sledge-
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Sledge- commented Apr 18, 2017

Is there a reason you have to write this to a canvas element vs. svg? This is the only example I have come across where this was done. Just curious as to why.

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