Not too long ago, I noted on Twitter that it'd be fantastic if, one day, CSS3 provided support for adding noise to elements (not audio, but texture). After a bit of experimentation and Googling, I came across a solution that uses JavaScript and canvas to dynamically create noise.
The Screencast
Final Source
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<!DOCTYPE html>
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<html lang="en"> |
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<head>
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<meta charset="UTF-8" /> |
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<title>Noise</title> |
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</head>
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<body>
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<script>
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function generateNoise(opacity) { |
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if ( !!!document.createElement('canvas').getContext ) { |
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return false; |
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}
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var canvas = document.createElement("canvas"), |
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ctx = canvas.getContext('2d'), |
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x, y, |
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number, |
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opacity = opacity || .2; |
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canvas.width = 45; |
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canvas.height = 45; |
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for ( x = 0; x < canvas.width; x++ ) { |
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for ( y = 0; y < canvas.height; y++ ) { |
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number = Math.floor( Math.random() * 60 ); |
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ctx.fillStyle = "rgba(" + number + "," + number + "," + number + "," + opacity + ")"; |
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ctx.fillRect(x, y, 1, 1); |
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}
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}
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document.body.style.backgroundImage = "url(" + canvas.toDataURL("image/png") + ")"; |
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}
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generateNoise(.1); // default opacity is .2 |
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</script>
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</body>
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</html>
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Conclusion
The big question: is it practical to use a solution like this? Ehh -- technically, sure. Browsers that don't support canvas will simply display a solid background color. That being said, a tiny 24-bit PNG still works perfectly, and is what I'll most likely continue to use until a more convenient solution becomes available.
What do you think? Or better yet, do you know of a better solution? Mostly, the purpose of this tutorial is mostly to work with canvas a bit, and toy around with things! Thanks for watching, and thank you to Dennis Hotson for the concept.
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