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@tafsiri
Last active Sep 16, 2015
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<html lang="en">
<head>
<meta charset="utf-8">
<title>2D Picking with SVG</title>
<meta name="description" content="">
<meta name="author" content="Yannick Assogba">
<script src="https://cdnjs.cloudflare.com/ajax/libs/stats.js/r14/Stats.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.5/dat.gui.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.6/d3.min.js"></script>
</head>
<body>
<div id='container'>
</div>
<script src="index.js"></script>
</body>
</html>
window.addEventListener('load', function(){
var stats = new Stats();
stats.setMode( 0 ); // 0: fps, 1: ms, 2: mb
// align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left = '0px';
stats.domElement.style.top = '0px';
document.body.appendChild( stats.domElement );
var width = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
var height = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
/*
Generate the data.
*/
var data = [];
function makeData(count) {
data = [];
for(var i = 0; i < count; i++) {
var w = 10 + Math.random() * 20;
var obj = {
x: Math.random() * (width - 20),
y: Math.random() * (height - 20),
xVel: (Math.random() * 0.5) * (Math.random() < 0.5 ? -1 : 1),
yVel: (Math.random() * 0.5) * (Math.random() < 0.5 ? -1 : 1),
width: w,
height: w,
index: i
};
data.push(obj);
}
return data;
}
var controls = {count:100};
var gui = new dat.GUI();
var controller = gui.add(controls, 'count', 0, 20000).step(100);
controller.onChange(function(value) {
data = makeData(value);
});
/*
Updates the nodes on each frame to make them bounce around the screen.
*/
function update(data) {
var numElements = data.length;
for(var i = 0; i < numElements; i++) {
var node = data[i];
node.x += node.xVel;
node.y += node.yVel;
if(node.x > width || node.x < 0) {
node.xVel *= -1;
}
if(node.y > height || node.y < 0) {
node.yVel *= -1;
}
}
}
function init(container) {
var svg = d3.select(container)
.append('svg')
.attr('width', width)
.attr('height', height);
return svg;
}
function draw(data, selection) {
var nodes = selection.selectAll("rect.node")
.data(data, function(d) { return d.index; });
nodes.enter()
.append('rect')
.attr('class', 'node')
.on('click', function(d){
d.renderCol = 'Orange';
});
nodes
.attr('width', function(d){ return d.width; })
.attr('height', function(d){ return d.height; })
.attr('x', function(d){ return d.x; })
.attr('y', function(d){ return d.y; })
.style('opacity', 0.8)
.style('fill', function(d){
if(d.renderCol){
return d.renderCol;
} else {
return 'DimGray';
}
});
nodes.exit()
.remove();
}
// Generate the data and start the draw loop.
var svg = init(document.querySelector('#container'));
data = makeData(100);
function animate() {
stats.begin();
draw(data, svg);
update(data);
stats.end();
window.requestAnimationFrame(animate);
}
window.requestAnimationFrame(animate);
}, false);
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