我制作了一个窗口大小的画布元素,并用随机值填充(以便我可以轻松地看到它更新)。当窗口使用<body onresize="updateCanvas();">
时它会调整大小,并且速度很慢。这就是它将会如何,还是有更好的方法来做到这一点?快速调整大型画布元素
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Window Sized Canvas</title>
<!-- <link href="style.css" rel="stylesheet" type="text/css"/>
Relevant style below: -->
<style type="text/css">
body {margin:0; padding:0;}
canvas {display:block;}
</style>
</head>
<body onresize="updateCanvas();">
<canvas id="hCanvas">Your browser does not support the canvas tag</canvas>
<script type="text/javascript">
var jCanvas = document.getElementById("hCanvas");
var jc2D = jCanvas.getContext("2d");
updateCanvas();
function updateCanvas() {
jCanvas.width = window.innerWidth;
jCanvas.height = window.innerHeight;
var jcW = jCanvas.width;
var jcH = jCanvas.height;
var jcWH4 = (jcW*jcH)<<2;
var jcImageData = jc2D.createImageData(jcW, jcH);
for (i = 0; i < jcWH4; i += 4) {
jcImageData.data[i] = (Math.random()*255)|0;
jcImageData.data[i+1] = (Math.random()*255)|0;
jcImageData.data[i+2] = (Math.random()*255)|0;
jcImageData.data[i+3] = 255;
}
jc2D.putImageData(jcImageData, 0, 0);
}
</script>
</body>
</html>
编辑:我发现一些不错的代码限制onresize()
。我只是发布不同于上面的内容:
...
<body onresize="resizeTimer();">
...
var resizeDelay;
function resizeTimer() {
clearTimeout(resizeDelay);
resizeDelay = setTimeout("updateCanvas()", 200);
}
...
谢谢,这将对我想要做的一些事情有效。其他人应该与窗口成比例,所以我想我会用交替像素线的通过来填充这些线(直到所有像素线被填充)。 – asimes 2013-03-02 00:07:32