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Three.js mouse-directed zoom
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<!DOCTYPE html> | |
<meta charset="utf-8"> | |
<canvas width="960" height="500"></canvas> | |
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/87/three.min.js"></script> | |
<script src="https://d3js.org/d3.v4.min.js"></script> | |
<script> | |
var canvas = d3.select("canvas"), | |
context = canvas.node().getContext("2d"), | |
width = canvas.property("width"), | |
height = canvas.property("height"), | |
radius = 2.5; | |
var points = d3.range(2000).map(phyllotaxis(10)); | |
canvas.call(d3.zoom() | |
.scaleExtent([1 / 2, 4]) | |
.on("zoom", zoomed)); | |
drawPoints(); | |
function zoomed() { | |
context.save(); | |
context.clearRect(0, 0, width, height); | |
context.translate(d3.event.transform.x, d3.event.transform.y); | |
context.scale(d3.event.transform.k, d3.event.transform.k); | |
drawPoints(); | |
context.restore(); | |
} | |
function drawPoints() { | |
context.beginPath(); | |
points.forEach(drawPoint); | |
context.fill(); | |
} | |
function drawPoint(point) { | |
context.moveTo(point[0] + radius, point[1]); | |
context.arc(point[0], point[1], radius, 0, 2 * Math.PI); | |
} | |
function phyllotaxis(radius) { | |
var theta = Math.PI * (3 - Math.sqrt(5)); | |
return function(i) { | |
var r = radius * Math.sqrt(i), a = theta * i; | |
return [ | |
width / 2 + r * Math.cos(a), | |
height / 2 + r * Math.sin(a) | |
]; | |
}; | |
} | |
</script> |
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