47 lines
704 B
Markdown
47 lines
704 B
Markdown
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# raf
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request animation frame
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## Installation
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$ component install component/raf
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## Example
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Request the animation frame with `raf(fn)`, cancel with `raf.cancel(id)`.
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```js
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var x = 0;
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var y = 50;
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var canvas = document.querySelector('canvas');
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var ctx = canvas.getContext('2d');
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var raf = require('raf');
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function animate() {
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raf(animate);
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draw();
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}
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var prev = Date.now();
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function draw() {
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var curr = Date.now();
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var diff = curr - prev;
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var p = diff / 16;
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ctx.clearRect(0, 0, 900, 300);
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ctx.beginPath();
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ctx.globalAlpha = .5;
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ctx.arc(x, y, 10, 0, Math.PI * 2, false);
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ctx.fill();
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x += 2;
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y += Math.sin(x/20) * 5;
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prev = curr;
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}
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animate();
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```
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## License
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MIT
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