日期:2014-05-16 浏览次数:21059 次

var canvas = document.getElementById("canvas");
var context = canvas.getContext('2d');
var Width=canvas.width;
var Height=canvas.height;
var s = "HTML 5 旋转";
context.font="lighter 1.5em palatino";
var colors = ["orange","blue","red"];
function drawText(s,x,y){
context.save();
// 旋转文本
for (var i = 0; i < 12; i++) {
context.rotate(30 * Math.PI / 180);
context.strokeStyle=colors[i % 3];
context.strokeText(s, 0, 0);
}
context.restore();
}
var angle=0;
var loop = setInterval(function () {
context.clearRect(0, 0, canvas.width, canvas.height);
context.save();
// 平移原点到图形环境的中心
context.translate(Width/2,Height/2);
context.rotate(angle * Math.PI / 180);
drawText(s,Width/2,Height/2,angle);
context.restore();
angle = (angle + 10) % 360;
}, 500);