13帧动画
2016-12-07 本文已影响15人
夜幕小草
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Canvas绘制帧动画</title>
</head>
<body style="padding: 100px;">
<canvas id="canvas" width="900" height="600" style="border:1px solid #000"></canvas>
<p></p>
<button dir="2">上</button>
<button dir="6">下</button>
<button dir="0">左</button>
<button dir="4">右</button>
<script>
// 1. 获取标签
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
// 2. 加载图片
// 2.1 裁剪的图片的宽高
var clipImgWH = 256;
var duration = 400; // ms
var dir = 0; // 默认向左
var image = new Image();
image.src = 'images/girl.png';
image.addEventListener('load', function () {
// 备份指针
var self = this;
var index = 0;
setInterval(function () {
// 清屏
ctx.clearRect(0, 0, canvas.width, canvas.height);
// 绘制
ctx.drawImage(self, index * clipImgWH, dir * clipImgWH, clipImgWH, clipImgWH, 200, 200, clipImgWH, clipImgWH );
index += 1;
// 对列数求余 --> 让图片循环
index %= 8;
}, duration);
});
// 改变方向
var buttonList = document.querySelectorAll("button");
for(var i=0; i<buttonList.length; i++){
buttonList[i].addEventListener('click', function () {
dir = this.getAttribute('dir'); // 改变方向
});
}
</script>
</body>
</html>
