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@LuisSevillano
Last active October 30, 2017 09:33
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Poisson-Disc
license: gpl-3.0
border: none
height: 600
<!DOCTYPE html>
<meta charset="utf-8">
<body>
<script src="//d3js.org/d3.v4.min.js"></script>
<script>
// based on https://bl.ocks.org/mbostock/19168c663618b7f07158
var margin = {top: 20, right: 10, bottom: 20, left: 10},
width = 900 - margin.left - margin.right,
height = 600 - margin.top - margin.bottom,
r = 13,
radious = 14;
var sample = poissonDiscSampler(width, height, radious);
var svg = d3.select("body").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom);
d3.timer(function() {
for (var i = 0; i < 100; ++i) {
var s = sample();
if (!s) return true;
svg.append("image")
.attr('xlink:href', 'icon.png')
.attr("x", s[0])
.attr("y", s[1])
.attr('height', '0')
.attr('width', '0')
.transition()
.attr('height', r)
.attr('width', r)
}
});
// Based on https://www.jasondavies.com/poisson-disc/
function poissonDiscSampler(width, height, radius) {
var k = 30, // maximum number of samples before rejection
radius2 = radius * radius,
R = 3 * radius2,
cellSize = radius * Math.SQRT1_2,
gridWidth = Math.ceil(width / cellSize),
gridHeight = Math.ceil(height / cellSize),
grid = new Array(gridWidth * gridHeight),
queue = [],
queueSize = 0,
sampleSize = 0;
return function() {
if (!sampleSize) return sample(Math.random() * width, Math.random() * height);
// Pick a random existing sample and remove it from the queue.
while (queueSize) {
var i = Math.random() * queueSize | 0,
s = queue[i];
// Make a new candidate between [radius, 2 * radius] from the existing sample.
for (var j = 0; j < k; ++j) {
var a = 2 * Math.PI * Math.random(),
r = Math.sqrt(Math.random() * R + radius2),
x = s[0] + r * Math.cos(a),
y = s[1] + r * Math.sin(a);
// Reject candidates that are outside the allowed extent,
// or closer than 2 * radius to any existing sample.
if (0 <= x && x < width && 0 <= y && y < height && far(x, y)) return sample(x, y);
}
queue[i] = queue[--queueSize];
queue.length = queueSize;
}
};
function far(x, y) {
var i = x / cellSize | 0,
j = y / cellSize | 0,
i0 = Math.max(i - 2, 0),
j0 = Math.max(j - 2, 0),
i1 = Math.min(i + 3, gridWidth),
j1 = Math.min(j + 3, gridHeight);
for (j = j0; j < j1; ++j) {
var o = j * gridWidth;
for (i = i0; i < i1; ++i) {
if (s = grid[o + i]) {
var s,
dx = s[0] - x,
dy = s[1] - y;
if (dx * dx + dy * dy < radius2) return false;
}
}
}
return true;
}
function sample(x, y) {
var s = [x, y];
queue.push(s);
grid[gridWidth * (y / cellSize | 0) + (x / cellSize | 0)] = s;
++sampleSize;
++queueSize;
return s;
}
}
</script>
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