这次给大家带来JS+canvas做出围绕旋转动画，JS+canvas做出围绕旋转动画的注意事项有哪些，下面就是实战案例，一起来看一下。
使用canvas的convas来实现围绕旋转动画，外圈顺时针，里层逆时针
html文件
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
<style>
body {
margin: 0;
padding: 0;
overflow: hidden;
background-color: #f0f0f0;
}
</style>
<script src="js/konva.js"></script>
<script src="js/circle.js"></script>
</head>
<body>
<p id="cas"></p>
<script>
var width = window.innerWidth;
var height = window.innerHeight;
//创建舞台
var stage = new Konva.Stage({
container: "cas",
width: width,
height: height
});
//创建层
var layer = new Konva.Layer();
//创建组1
var group = new Konva.Group({
x: stage.width() / 2,
y: stage.height() / 2,
});
//最外层圆
var circle1 = new Konva.Circle({
x: 0,
y: 0,
radius: 250,
stroke: "#ccc",
strokeWidth: 1,
dash: [6, 3]
});
group.add(circle1);
//第二个圆
var circle2 = new Konva.Circle({
x: 0,
y: 0,
radius: 150,
stroke: "#ccc",
strokeWidth: 1,
dash: [6, 3]
});
group.add(circle2);
//第三个圆
var circle3 = new Konva.Circle({
x: 0,
y: 0,
radius: 135,
stroke: "blue",
strokeWidth: 2,
dash: [10, 5]
});
group.add(circle3);
//第四个圆
var circle4 = new Konva.Circle({
x: 0,
y: 0,
radius: 105,
fill: "#ccc",
opacity: 0.4
});
group.add(circle4);
//第五个圆
var circle5 = new Konva.Circle({
x: 0,
y: 0,
radius: 80,
fill: "#74A2F0"
});
group.add(circle5);
//添加文字
var text = new Konva.Text({
x: -80,
y: -12,
text: "WEB全栈",
fill: "white",
fontSize: 24,
width: 160,
align: "center"
});
group.add(text);
layer.add(group);
//*****************************************************
//创建组2
var outGroup = new Konva.Group({
x: stage.width() / 2,
y: stage.height() / 2,
});
var arrColor = ["red", "green", "blue", "orange", "purple"];
var arrText = ["web", "node.js", "ajax", "html5", "css"];
for(var i = 0; i < 5; i++) {
var cir = new Circle({
x : 250 * Math.cos(72 * i * Math.PI / 180), //圆心x轴的坐标
y : 250 * Math.sin(72 * i * Math.PI / 180), //圆心y轴的坐标
outR : 60, //外圆的半径
inR : 50, //内圆的半径
fill : arrColor[i], //填充颜色
text: arrText[i], //文字
outOpacity : 0.3, //外圆的透明度
inOpacity : 0.6 //内圆的透明度
});
cir.drawCircle(outGroup);
}
layer.add(outGroup);
//***********************************************
//创建组3
var inGroup = new Konva.Group({
x: stage.width() / 2,
y: stage.height() / 2,
});
var arrColor = ["red", "green", "blue", "orange", "purple"];
var arrText = ["web", "node.js", "ajax", "html5", "css"];
for(var i = 0; i < 5; i++) {
var cir = new Circle({
x : 135 * Math.cos(90 * i * Math.PI / 180), //圆心x轴的坐标
y : 135 * Math.sin(90 * i * Math.PI / 180), //圆心y轴的坐标
outR : 45, //外圆的半径
inR : 35, //内圆的半径
fill : arrColor[i], //填充颜色
text: arrText[i], //文字
outOpacity : 0.3, //外圆的透明度
inOpacity : 0.6 //内圆的透明度
});
cir.drawCircle(inGroup);
}
layer.add(inGroup);
//************************************************
//运动动画
var step = 1; //转动的角度
var anim = new Konva.Animation(function() {
outGroup.rotate(step);
outGroup.getChildren().each(function (ele, index) {
ele.rotate(-step);
});
inGroup.rotate(-step);
inGroup.getChildren().each(function (ele, index) {
ele.rotate(step);
});
}, layer);
anim.start();
stage.add(layer);
stage.on("mouseover", function () {
step = 0.3;
});
stage.on("mouseout", function () {
step = 1;
});
</script>
</body>
</html>js文件
function Circle(obj) {
this._init(obj);
}
Circle.prototype = {
_init: function (obj) {
this.x = obj.x, //圆心x轴的坐标
this.y = obj.y, //圆心y轴的坐标
this.outR = obj.outR, //外圆的半径
this.inR = obj.inR, //内圆的半径
this.color = obj.fill, //填充颜色
this.text = obj.text, //内圆的文字
this.outOpacity = obj.outOpacity, //外圆的透明度
this.inOpacity = obj.inOpacity //内圆的透明度
},
drawCircle: function (group) {
//创建一个组
var groupCir = new Konva.Group({
x: this.x,
y: this.y
});
//外圆
var outCir = new Konva.Circle({
x: 0,
y: 0,
radius: this.outR,
fill: this.color,
opacity: this.outOpacity
});
groupCir.add(outCir);
//内圆
var inCir = new Konva.Circle({
x: 0,
y: 0,
radius: this.inR,
fill: this.color,
opacity: this.inOpacity
});
groupCir.add(inCir);
//添加文字
var text = new Konva.Text({
x: -this.inR,
y: -10,
text: this.text,
fill: "white",
fontSize: 20,
width: 2 * this.inR,
align: "center"
});
groupCir.add(text);
group.add(groupCir);
}
}相信看了本文案例你已经掌握了方法，更多精彩请关注php中文网其它相关文章！
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以上是JS+canvas做出围绕旋转动画的详细内容。更多信息请关注PHP中文网其他相关文章！
