运行效果:

<!DOCTYPE html>
<html>
<head>
</head>
<body>
<canvas id="drawing" width="1000" height="600">A drawing of someing!</canvas>
<script type="text/javascript">
var drawing = document.getElementById(‘drawing‘);
if(drawing.getContext) {
//绘制马尾图案
var context = drawing.getContext(‘2d‘);
//随机颜色
var addZero = function(str){
return str.length === 2 ? str : ‘0‘+str;
};
var randomColor = function(redValue, greenValue, blueValue){
redValue = addZero(redValue.toString(16));
greenValue = addZero(greenValue.toString(16));
blueValue = addZero(blueValue.toString(16));
return ‘#‘ + redValue + greenValue + blueValue;
};
context.translate(250, 100);
for(var i=0; i<50; i++) {
context.fillStyle = randomColor(parseInt(Math.random()*256), parseInt(Math.random()*256), parseInt(Math.random()*256));
context.scale(0.93, 0.93);//缩放
context.rotate(Math.PI/9);//旋转画布
context.translate(35, 12);
context.fillRect(0, 0, 100, 50);
}
}
</script>
</body>
</html>
canvas一周一练 -- canvas绘制马尾图案 (5)
原文:http://www.cnblogs.com/merryZhang/p/7206501.html