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d3-bboxCollide

d3-bboxCollide provides bounding box collision detection for d3.forceSimulation. This is useful for label adjustment or rectangular nodes. Each node receives a bounding box array of a top right and bottom left corner of that node relative to its x position. In the case of this dataset, that size is based on the length of the word in the source dataset.

A function for calculating this array based off the data is passed into the d3.bboxCollide function, which is later passed as a "collide" constraint in your force settings.

var collide = d3.bboxCollide(function (d,i) {
    return [[-d.value * 10, -d.value * 5],[d.value * 10, d.value * 5]]
  })

The code above creates a rectangle scaled to the size of the randomized data. The data determines the y position creating a sort of rectilinear beeswarm plot.

(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-quadtree')) :
typeof define === 'function' && define.amd ? define(['exports', 'd3-quadtree'], factory) :
(factory((global.d3 = global.d3 || {}),global.d3));
}(this, function (exports,d3Quadtree) { 'use strict';
function bboxCollide (bbox) {
function x (d) {
return d.x + d.vx;
}
function y (d) {
return d.y + d.vy;
}
function constant (x) {
return function () {
return x;
};
}
var nodes,
boundingBoxes,
strength = 1,
iterations = 1;
if (typeof bbox !== "function") {
bbox = constant(bbox === null ? [[0,0][1,1]] : bbox)
}
function force () {
var i,
tree,
node,
xi,
yi,
bbi,
nx1,
ny1,
nx2,
ny2
var cornerNodes = []
nodes.forEach(function (d, i) {
cornerNodes.push({node: d, vx: d.vx, vy: d.vy, x: d.x + (boundingBoxes[i][1][0] + boundingBoxes[i][0][0]) / 2, y: d.y + (boundingBoxes[i][0][1] + boundingBoxes[i][1][1]) / 2})
cornerNodes.push({node: d, vx: d.vx, vy: d.vy, x: d.x + boundingBoxes[i][0][0], y: d.y + boundingBoxes[i][0][1]})
cornerNodes.push({node: d, vx: d.vx, vy: d.vy, x: d.x + boundingBoxes[i][0][0], y: d.y + boundingBoxes[i][1][1]})
cornerNodes.push({node: d, vx: d.vx, vy: d.vy, x: d.x + boundingBoxes[i][1][0], y: d.y + boundingBoxes[i][0][1]})
cornerNodes.push({node: d, vx: d.vx, vy: d.vy, x: d.x + boundingBoxes[i][1][0], y: d.y + boundingBoxes[i][1][1]})
})
var cn = cornerNodes.length
for (var k = 0; k < iterations; ++k) {
tree = d3Quadtree.quadtree(cornerNodes, x, y).visitAfter(prepareCorners);
for (i = 0; i < cn; ++i) {
var nodeI = ~~(i / 5);
node = nodes[nodeI]
bbi = boundingBoxes[nodeI]
xi = node.x + node.vx
yi = node.y + node.vy
nx1 = xi + bbi[0][0]
ny1 = yi + bbi[0][1]
nx2 = xi + bbi[1][0]
ny2 = yi + bbi[1][1]
tree.visit(apply);
}
}
function apply (quad, x0, y0, x1, y1) {
var data = quad.data
if (data) {
var bWidth = bbLength(bbi, 0),
bHeight = bbLength(bbi, 1);
if (data.node.index !== nodeI) {
var dataNode = data.node
var bbj = boundingBoxes[dataNode.index],
dnx1 = dataNode.x + dataNode.vx + bbj[0][0],
dny1 = dataNode.y + dataNode.vy + bbj[0][1],
dnx2 = dataNode.x + dataNode.vx + bbj[1][0],
dny2 = dataNode.y + dataNode.vy + bbj[1][1],
dWidth = bbLength(bbj, 0),
dHeight = bbLength(bbj, 1)
if (nx1 <= dnx2 && dnx1 <= nx2 && ny1 <= dny2 && dny1 <= ny2) {
var xSize = [Math.min.apply(null, [dnx1, dnx2, nx1, nx2]), Math.max.apply(null, [dnx1, dnx2, nx1, nx2])]
var ySize = [Math.min.apply(null, [dny1, dny2, ny1, ny2]), Math.max.apply(null, [dny1, dny2, ny1, ny2])]
var xOverlap = bWidth + dWidth - (xSize[1] - xSize[0])
var yOverlap = bHeight + dHeight - (ySize[1] - ySize[0])
var xBPush = xOverlap * strength * (yOverlap / bHeight)
var yBPush = yOverlap * strength * (xOverlap / bWidth)
var xDPush = xOverlap * strength * (yOverlap / dHeight)
var yDPush = yOverlap * strength * (xOverlap / dWidth)
if ((nx1 + nx2) / 2 < (dnx1 + dnx2) / 2) {
node.vx -= xBPush
dataNode.vx += xDPush
}
else {
node.vx += xBPush
dataNode.vx -= xDPush
}
if ((ny1 + ny2) / 2 < (dny1 + dny2) / 2) {
node.vy -= yBPush
dataNode.vy += yDPush
}
else {
node.vy += yBPush
dataNode.vy -= yDPush
}
}
}
return;
}
return x0 > nx2 || x1 < nx1 || y0 > ny2 || y1 < ny1;
}
}
function prepareCorners (quad) {
if (quad.data) {
return quad.bb = boundingBoxes[quad.data.node.index]
}
quad.bb = [[0,0],[0,0]]
for (var i = 0; i < 4; ++i) {
if (quad[i] && quad[i].bb[0][0] < quad.bb[0][0]) {
quad.bb[0][0] = quad[i].bb[0][0]
}
if (quad[i] && quad[i].bb[0][1] < quad.bb[0][1]) {
quad.bb[0][1] = quad[i].bb[0][1]
}
if (quad[i] && quad[i].bb[1][0] > quad.bb[1][0]) {
quad.bb[1][0] = quad[i].bb[1][0]
}
if (quad[i] && quad[i].bb[1][1] > quad.bb[1][1]) {
quad.bb[1][1] = quad[i].bb[1][1]
}
}
}
function bbLength (bbox, heightWidth) {
return bbox[1][heightWidth] - bbox[0][heightWidth]
}
force.initialize = function (_) {
var i, n = (nodes = _).length; boundingBoxes = new Array(n);
for (i = 0; i < n; ++i) boundingBoxes[i] = bbox(nodes[i], i, nodes);
};
force.iterations = function (_) {
return arguments.length ? (iterations = +_, force) : iterations;
};
force.strength = function (_) {
return arguments.length ? (strength = +_, force) : strength;
};
force.bbox = function (_) {
return arguments.length ? (bbox = typeof _ === "function" ? _ : constant(+_), force) : bbox;
};
return force;
}
exports.bboxCollide = bboxCollide;
Object.defineProperty(exports, '__esModule', { value: true });
}));
<html>
<head>
<title>Bounding Box Collision</title>
<meta charset="utf-8" />
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="collide.js"></script>
</head>
<style>
svg {
height: 500px;
width: 500px;
border: 1px solid lightgray;
}
</style>
<body>
<div id="viz">
<svg class="main">
</svg>
</div>
</body>
<footer>
<script>
var randomPoints = d3.range(500).map(function () {
return {value: Math.random()}
})
var networkCenter = d3.forceCenter().x(250).y(250);
var forceX = d3.forceX(function (d) {return 100})
.strength(0.1)
var forceY = d3.forceY(function (d) {return d.value * 500})
.strength(1)
var collide = d3.bboxCollide(function (d,i) {
return [[-d.value * 10, -d.value * 5],[d.value * 10, d.value * 5]]
})
.strength(1)
.iterations(2)
var color = d3.scaleOrdinal(d3.schemeCategory20b)
var force = d3.forceSimulation(randomPoints)
.velocityDecay(0.6)
.force("center", networkCenter)
.force("x", forceX)
.force("y", forceY)
.force("collide", collide)
.on("tick", updateNetwork);
var nodeEnter = d3.select("svg.main")
.append("g")
.selectAll("g.node")
.data(randomPoints)
.enter()
.append("g")
.attr("class", "node")
nodeEnter.append("rect")
.attr("class", "base")
.style("fill-opacity", 0.75)
.style("stroke-width", 1)
.style("stroke-opacity", 0.5)
.style("stroke", function (d, i) {return d3.color(color(i)).darker(2)})
.style("fill", function (d, i) {return d3.color(color(i)).brighter(2)})
.style("width", function (d) {return d.value * 20})
.style("height", function (d) {return d.value * 10})
.style("x", function (d) {return -d.value * 10})
.style("y", function (d) {return -d.value * 5})
function updateNetwork() {
d3.select("svg.main").selectAll("g.node")
.attr("transform", function (d) {return "translate(" + d.x + "," + d.y + ")"})
}
</script>
</footer>
</html>
@timelyportfolio
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timelyportfolio commented Sep 23, 2016

Each node receives a bounding box array of a top right and bottom left corner of that node

do you mean top left and bottom right?

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