我想要使用html5制作一个球,并且我实现了这个小脚本。但是,我看不到任何动画。我该如何解决这个问题?为什么这个requestAnmationFrame脚本不起作用?
<html>
<head>
<meta charset="utf-8">
<script>
canvas = document.getElementById("canvas");
window.onload=function(){
if (document.createElement("canvas").getContext){
//alert("browser supports canvas");
//console.log(document.getElementById("canvas").getContext);
canvas = document.getElementById("canvas");
shape = new shapes();
shape.drawball(canvas,100,"red");
}
};
function shapes(){
this.drawtriangle = function(canvas){
triangles = new triangle(0,0,0,200,200,200);
triangles.draw(canvas.getContext('2d'));
}
this.drawball = function(canvas,radius,color) {
ball = new Ball(radius,color);
ball.draw(canvas.getContext('2d'),canvas);
}
}
function coordinates(x1,y1){
this.x = x1;
this.y = y1;
}
function angle(angle,speed){
this.angle = angle;
this.speed = speed;
}
function Ball(radius,color){
this.origin = new coordinates(100,100);
this.radius = (radius === "undefined") ? 40 : radius;
this.color = (color === "undefined") ? red : color;
this.rotation = 0;
this.index = 0;
this.angles = new angle(0,0.2);
}
Ball.prototype.draw = function(context,canvas){
context.fillStyle = this.color;
context.strokeStyle = "blue";
context.rotate(this.rotation);
context.beginPath();
context.arc(this.origin.x,this.origin.y,this.radius,0,(Math.PI*2),true)
context.closePath();
context.fill();
context.stroke();
this.animate(context,canvas);
}
Ball.prototype.animate = function(context,canvas){
if (this.angles.angle < 1){
context.clearRect(0,0,1000,1000);
console.log("Animating ... ");
this.origin.x = this.origin.x + 10;
this.origin.y = this.origin.y + 10;
this.angles.angle = this.angles.angle + this.angles.speed;
window.requestAnimationFrame(this.draw(context));
}
}
</script>
<style>
body {
background-color: #bbb;
}
#canvas {
background-color: #fff;
}
</style>
</head>
<body>
<canvas id="canvas" width="1000px" height="1000px">
Your browser dows bot suppoet canvas
</canvas>
</body>
</html>
它不WRK still..Here是在控制台动画化输出... 未捕获的类型错误:对象[对象窗口]没有方法'draw' –
浏览器报告的脚本错误是什么?由于您未包含所有代码,因此我们无法自行运行以进行调试。 – jfriend00
我已经包含它 –