canvas炫酷烟花绽放粒子动画效果代码-html代码-BFW代码库

canvas炫酷烟花绽放粒子动画效果代码

代码语言：html

所属分类：粒子

代码描述：canvas炫酷烟花绽放粒子动画效果代码

下面为部分代码预览，完整代码请点击下载或在bfwstudio webide中打开

<!DOCTYPE html>
<html lang="en" >
<head>
  <meta charset="UTF-8">
<style>
    body, html {
    background-color: #000;
    color: #fff;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
}
canvas {
    position:absolute;
    top:0;
    left:0
}
</style>

</head>
<body>

<canvas id="canvas"></canvas>

  <script >
      (function () {
    var requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;
    window.requestAnimationFrame = requestAnimationFrame;
})();


var canvas = document.getElementById("canvas"),
    ctx = canvas.getContext("2d"),
    width = 0,
    height = 0,
    vanishPointY = 0,
    vanishPointX = 0,
    focalLength = 300,
    angleX = 180,
    angleY = 180,
    angleZ = 180,
    angle = 0,
    cycle = 0,
    colors = {r : 255, g : 0, b : 0},
    lastShot = new Date().getTime();

canvas.width = width;
canvas.height = height;


function drawStar(cx, cy, spikes, outerRadius, innerRadius) {
    var rot = Math.PI / 2 * 3;
    var x = cx;
    var y = cy;
    var step = Math.PI / spikes;

    ctx.strokeSyle = "#000";
    ctx.beginPath();
    ctx.moveTo(cx, cy - outerRadius)
    for (i = 0; i < spikes; i++) {
        x = cx + Math.cos(rot) * outerRadius;
        y = cy + Math.sin(rot) * outerRadius;
        ctx.lineTo(x, y)
        rot += step

        x = cx + Math.cos(rot) * innerRadius;
        y = cy + Math.sin(rot) * innerRadius;
        ctx.lineTo(x, y)
        rot += step
    }
    ctx.lineTo(cx, cy - outerRadius)
    ctx.closePath();
    ctx.lineWidth=2;
    ctx.strokeStyle='goldenrod';
    ctx.stroke();
    ctx.fillStyle='yellow';
    ctx.fill();

}


/*
 *	Controls the emitter
 */
function Emitter() {
    this.reset();
}

Emitter.prototype.reset = function () {
    var PART_NUM = 200,
        x = (Math.random() * 400) - 200,
        y = (Math.random() * 400) - 200,
        z = (Math.random() * 800) - 200;
    
    this.x = x || 0;
    this.y = y || 0;
    this.z = z || 0;
    
    var color = [~~(Math.random() * 150) + 10, ~~(Math.random() * 150) + 10, ~~(Math.random() * 150) + 10]
    this.particles = [];

    for (var i = 0; i < PART_NUM; i++) {
        this.particles.push(new Particle(this.x, this.y, this.z, {
            r: colors.r,
            g: colors.g,
            b: colors.b
        }));
    }
}

Emitter.prototype.update = function () {
    var partLen = this.particles.length;

    angleY = (angle - vanishPointX) * 0.0001;
    angleX = (angle - vanishPointX) * 0.0001;

    this.particles.sort(function (a, b) {
        return b.z - a.z;
    });

    for (var i = 0; i < partLen; i++) {
        this.particles[i].update();
    }
    
    if(this.particles.length <= 0){
      this.reset();   
    }

};

Emitter.prototype.render = function (imgData) {
    var data = imgData.data;

    for (i = 0; i < this.particles.length; i++) {
        var particle = this.particles[i],
            dist = Math.sqrt((particle.x - particle.ox) * (particle.x - particle.ox) + (particle.y - particle.oy) * (particle.y - particle.oy) + (particle.z - particle.oz) * (particle.z - particle.oz));

        if (dist > 255) {
            particle.render = false;
            thi.........完整代码请登录后点击上方下载按钮下载查看