JavaScript Canvas实现兼容IE的兔子发射爆破动图特效
作者：zkj
这篇文章主要为大家介绍了JavaScript Canvas实现兼容IE的兔子发射爆破动图特效示例详解，有需要的朋友可以借鉴参考下，希望能够有所帮助，祝大家多多进步，早日升职加薪
前言
Hello，同学们好！又是一年新春之际，祝福大家兔年快乐！给大家介绍一个有趣的动效（兼容 IE），页面右下角有一只搞怪的兔子，鼠标在页面中悬停时，兔子会跟着做出不同的动作和表情。然后可以在页面中任意位置（离兔子太近不能发射，会伤到兔子😆）点击鼠标，将从兔子眼睛👀里发射炮弹，随之击中爆破的是你的霉 运、压 力、贫 穷、疾 病😮💨。
实现
定义一个随机文本块。
<p id="p1"></p>
定义兔子的构造函数
function HoverRabbit() {
this.explodeImage = new Image();
this.explodeImage.src = "img/explode.png";
for (var i = 1; i <= 6; i++) {
this.images[i] = new Image();
this.images[i].src = "img/s" + i + ".png";
}
if (typeof(CanvasGradient) != 'undefined') {
this.canvas = document.createElement("canvas");
this.canvas.width = screen.width + 100;
this.canvas.height = screen.height;
this.canvas.style.position = 'absolute';
this.canvas.style.left = '0px';
this.canvas.style.top = '0px';
this.canvas.style.display = 'none';
document.body.appendChild(this.canvas);
this.canvas.style.position = 'fixed';
}
}
定义兔子原型的属性和方法
HoverRabbit.prototype = {
images: [],
explodeImage: null,
eyePositions: [],
current: 1,
frame: 1,
canvas: null,
interval: null,
start: function() {
var me = this;
this.eyePositions[1] = {
eye1x: 123,
eye1y: 47,
eye2x: 104,
eye2y: 53
};
this.eyePositions[2] = {
eye1x: 120,
eye1y: 50,
eye2x: 101,
eye2y: 54
};
this.eyePositions[3] = {
eye1x: 119,
eye1y: 54,
eye2x: 97,
eye2y: 56
};
this.eyePositions[4] = {
eye1x: 112,
eye1y: 61,
eye2x: 90,
eye2y: 61
};
this.eyePositions[5] = {
eye1x: 105,
eye1y: 64,
eye2x: 85,
eye2y: 61
};
this.eyePositions[6] = {
eye1x: 98,
eye1y: 68,
eye2x: 79,
eye2y: 56
};
document.onmousemove = function(e) {
me.onmousemove(e);
}
if (this.canvas) {
document.addEventListener("click", function(e) {
me.ondblclick(e);
});
}
},
onmousemove: function(e) {
var event = e || window.event;
var deg = Math.abs(screen.height - event.screenY) / (Math.abs(screen.width - event.screenX) + 1);
var n = 1;
if (deg > 2) n = 6;
else if (deg > 1.4) n = 5;
else if (deg > 0.7) n = 4;
else if (deg > 0.45) n = 3;
else if (deg > 0.2) n = 2;
this.deg = n;
if (this.current != n) {
document.body.style.backgroundImage = "url(" + this.images[n].src + ")";
this.current = n;
}
},
drawBomb: function(ctxt, n, x, y) {
var sx = 64 * (n % 4);
var sy = 64 * (Math.floor(n / 4));
ctxt.drawImage(this.explodeImage, sx, sy, 64, 64, x - 32, y - 32, 64, 64);
},
ondblclick: function(e) {
if (this.canvas.style.display != 'none') return;
var me = this;
if (e.clientX > window.innerWidth - 200 && e.clientY > window.innerHeight - 200) return;
var ctxt = this.canvas.getContext("2d");
this.frame = 1;
this.interval = setInterval(function(e2) {
ctxt.clearRect(0, 0, me.canvas.width, me.canvas.height);
switch (me.frame) {
case 1:
ctxt.strokeStyle = 'rgba(247,166,71,1)';
me.canvas.style.display = 'block';
case 2:
if (me.frame == 2) {
ctxt.strokeStyle = 'rgba(247,166,71,0.5)';
me.drawBomb(ctxt, 0, e.clientX, e.clientY);
}
case 3:
if (me.frame == 3) {
ctxt.strokeStyle = 'rgba(247,166,71,0.1)';
me.drawBomb(ctxt, 1, e.clientX, e.clientY);
}
var eye1x = window.innerWidth - me.eyePositions[me.current].eye1x;
var eye1y = window.innerHeight - me.eyePositions[me.current].eye1y;
ctxt.lineWidth = 3;
ctxt.beginPath();
ctxt.moveTo(eye1x, eye1y);
ctxt.lineTo(e.clientX, e.clientY);
ctxt.stroke();
var eye2x = window.innerWidth - me.eyePositions[me.current].eye2x;
var eye2y = window.innerHeight - me.eyePositions[me.current].eye2y;
ctxt.beginPath();
ctxt.moveTo(eye2x, eye2y);
ctxt.lineTo(e.clientX, e.clientY);
p1.textContent = ['霉 运', '压 力', '贫 穷', '疾 病'][Math.floor(Math.random() * 4)];
p1.style.display = 'block';
p1.style.transform = 'rotate(' + (-150 + me.deg * 30) + 'deg)';
p1.style.left = e.clientX - 30 + 'px';
p1.style.top = e.clientY - 30 + 'px';
fade(p1);
ctxt.stroke();
break;
case 4:
me.drawBomb(ctxt, 2, e.clientX, e.clientY);
break;
case 14:
me.canvas.style.display = 'none';
window.clearInterval(me.interval);
break;
default:
me.drawBomb(ctxt, me.frame - 2, e.clientX, e.clientY);
}
me.frame++;
}, 50);
}
};
各个属性和方法说明：
- images - 兔子不同的动作的图片数组。
- explodeImage - 炮弹图片元素。
- eyePositions - 兔子眼睛位置的数组。
- current - 整型数字，兔子当前动作的指针。
- frame - 整型数字，发射炮弹动画的帧数指针。
- canvas - 画布元素。
- interval - 发射炮弹动画时间间隔定时器的 interval ID。
- start - 启动页面交互的方法，在这里初始化了兔子眼睛位置的数组数据，绑定页面鼠标移动事件、点击事件。
- onmousemove - 定义页面鼠标移动的实现方法。
- ondblclick - 定义页面鼠标点击的实现方法。
- drawBomb - 定义绘制和更新炮弹动画的方法。
定义文字淡出的动画。
function fade(e) {
var s = e.style;
s.opacity = 1;
(function hide() {
(s.opacity -= .01) < 0 ? s.display = "none" : requestAnimationFrame(hide);
})();
}
- 创建兔子对象，调用启动交互方法。
var s = new HoverRabbit(); s.start();
以上就是JavaScript Canvas实现兼容IE的兔子发射爆破动图特效的详细内容，更多关于JavaScript Canvas兼容IE动图的资料请关注脚本之家其它相关文章！