canvas可调参数的烟花定点绽放动画效果代码-html代码-BFW代码库

代码语言：html
所属分类：动画
代码描述：canvas可调参数的烟花定点绽放动画效果代码
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>
        html, body {
        	margin: 0;	
        	padding: 0;
        }
        
        body {
        	background: #171717;
        	color: #999;
        	font: 100%/18px helvetica, arial, sans-serif;
        }
        
        a {
        	color: #2fa1d6;
        	font-weight: bold;
        	text-decoration: none;
        }
        
        a:hover {
        	color: #fff;	
        }
        
        #canvas-container {
        	background: #000 url(//repo.bfw.wiki/bfwrepo/images/bg/bg.jpg);
          height: 400px;
        	left: 50%;
        	margin: -200px 0 0 -300px;
        	position: absolute;
        	top: 50%;
          width: 600px;
        	z-index: 2;
        }
        		
        canvas {
        	cursor: crosshair;
        	display: block;
        	position: relative;
        	z-index: 3;
        }
        
        canvas:active {
        	cursor: crosshair;
        }
        
        #skyline {
        	background: url(//repo.bfw.wiki/bfwrepo/images/bg/skyline.png) repeat-x 50% 0;
        	bottom: 0;
        	height: 135px;
        	left: 0;
        	position: absolute;
        	width: 100%;
        	z-index: 1;	
        }
        
        #mountains1 {
        	background: url(//repo.bfw.wiki/bfwrepo/images/bg/mountains1.png) repeat-x 40% 0;
        	bottom: 0;
        	height: 200px;
        	left: 0;
        	position: absolute;
        	width: 100%;
        	z-index: 1;	
        }
        
        #mountains2 {
        	background: url(//repo.bfw.wiki/bfwrepo/images/bg/mountains2.png) repeat-x 30% 0;
        	bottom: 0;
        	height: 250px;
        	left: 0;
        	position: absolute;
        	width: 100%;
        	z-index: 1;	
        }
        
        #gui {
        	right: 0;
        	position: fixed;
        	top: 0;
        	z-index: 3;
        }
    </style>


</head>

<body>
    <div id="gui"></div>
    <div id="canvas-container">
        <div id="mountains2"></div>
        <div id="mountains1"></div>
        <div id="skyline"></div>
    </div>

<script type="text/javascript" src="//repo.bfw.wiki/bfwrepo/js/jquery.2.11.js"></script>
<script type="text/javascript" src="//repo.bfw.wiki/bfwrepo/js/dat.gui-min.js"></script>
    <script >
        var Fireworks = function () {
          /*=============================================================================*/
          /* Utility
          /*=============================================================================*/
          var self = this;
          var rand = function (rMi, rMa) {return ~~(Math.random() * (rMa - rMi + 1) + rMi);};
          var hitTest = function (x1, y1, w1, h1, x2, y2, w2, h2) {return !(x1 + w1 < x2 || x2 + w2 < x1 || y1 + h1 < y2 || y2 + h2 < y1);};
          window.requestAnimFrame = function () {return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function (a) {window.setTimeout(a, 1E3 / 60);};}();
        
          /*=============================================================================*/
          /* Initialize
          /*=============================================================================*/
          self.init = function () {
            self.canvas = document.createElement('canvas');
            self.canvasContainer = $('#canvas-container');
        
            var canvasContainerDisabled = document.getElementById('canvas-container');
            self.canvas.onselectstart = function () {
              return false;
            };
        
            self.canvas.width = self.cw = 600;
            self.canvas.height = self.ch = 400;
        
            self.particles = [];
            self.partCount = 30;
            self.fireworks = [];
            self.mx = self.cw / 2;
            self.my = self.ch / 2;
            self.currentHue = 170;
            self.partSpeed = 5;
            self.partSpeedVariance = 10;
            self.partWind = 50;
            self.partFriction = 5;
            self.partGravity = 1;
            self.hueMin = 150;
            self.hueMax = 200;
            self.fworkSpeed = 2;
            self.fworkAccel = 4;
            self.hueVariance = 30;
            self.flickerDensity = 20;
            self.showShockwave = false;
            self.showTarget = true;
            self.clearAlpha = 25;
        
            self.canvasContainer.append(self.canvas);
            self.ctx = self.canvas.getContext('2d');
            self.ctx.lineCap = 'round';
            self.ctx.lineJoin = 'round';
            self.lineWidth = 1;
            self.bindEvents();
            self.canvasLoop();
        
            self.canvas.onselectstart = function () {
              return false;
            };
        
        
          };
        
          /*=============================================================================*/
          /* Particle Constructor
          /*=============================================================================*/
          var Particle = function (x, y, hue) {
            this.x = x;
            this.y = y;
            this.coordLast = [
            { x: x, y: y },
            { x: x, y: y },
            { x: x, y: y }];
        
            this.angle = rand(0, 360);
            this.speed = rand(self.partSpeed - self.partSpeedVariance <= 0 ? 1 : self.partSpeed - self.partSpeedVariance, self.partSpeed + self.partSpeedVariance);
            this.friction = 1 - self.partFriction / 100;
            this.gravity = self.partGravity / 2;
            this.hue = rand(hue - self.hueVariance, hue + self.hueVariance);
            this.brightness = rand(50, 80);
            this.alpha = rand(40, 100) / 100;
            this.decay = rand(10, 50) / 1000;
            this.wind = (rand(0, self.partWind) - self.partWind / 2) / 25;
            this.lineWidth = self.lineWidth;
          };
        
          Particle.prototype.update = function (index) {
            var radians = this.angle * Math.PI / 180;
            var vx = Math.cos(radians) * this.speed;
            var vy = Math.sin(radians) * this.speed + this.gravity;
            this.speed *= this.friction;
        
            this.coordLast[2].x = this.coordLast[1].x;
            this.coordLast[2].y = this.coordLast[1].y;
            this.coordLast[1].x = this.coordLast[0].x;
            this.coordLast[1].y = this.coordLast[0].y;
            this.coordLast[0].x = this.x;
            this.coordLast[0].y = this.y;
        
            this.x += vx;
            this.y += vy;
        
            this.angle += this.wind;
            this.alpha -= this.decay;
        
            if (!hitTest(0, 0, self.cw, self.ch, this.x - this.radius, this.y - this.radius, this.radius * 2, this.radius * 2) || this.alpha < .05) {
              self.particles.splice(index, 1);
            }
          };
        
          Particle.prototype.draw = function () {
            var coordRand = rand(1, 3) - 1;
            self.ctx.beginPath();
            self.ctx.moveTo(Math.round(this.coordLast[coordRand].x), Math.round(this.coordLast[coordRand].y));
            self.ctx.lineTo(Math.round(this.x), Math.round(this.y));
            self.ctx.closePath();
            self.ctx.strokeStyle = 'hsla(' + this.hue + ', 100%, ' + this.brightness + '%, ' + this.alpha + ')';
            self.ctx.stroke();
        
            if (self.flickerDensity > 0) {
              var inverseDensity = 50 - self.flickerDensity;
              if (rand(0, inverseDensity) === inverseDensity) {
                self.ctx.beginPath();
                self.ctx.arc(Math.round(this.x), Math.round(this.y), rand(this.lineWidth, this.lineWidth + 3) / 2, 0, Math.PI * 2, false);
                self.ctx.closePath();
                var randAlpha = rand(50, 100) / 100;
                self.ctx.fillStyle = 'hsla(' + this.hue + ', 100%, ' + this.brightness + '%, ' + randAlpha + ')';
                self.ctx.fill();
              }
            }
          };
        
          /*=============================================================================*/
          /* Create Particles
          /*=============================================================================*/
          self.createParticles = function (x, y, hue) {
            var countdown = self.partCount;
            while (countdown--) {
              self.particles.push(new Particle(x, y, hue));
            }
          };
        
          /*=============================================================================*/
          /* Update Particles
          /*=============================================================================*/
          self.updateParticles = function () {
            var i = self.particles.length;
            while (i--) {
              var p = self.particles[i];
              p.update(i);
            };
          };
        
          /*=============================================================================*/
          /* Draw Particles
          /*=============================================================================*/
          self.drawParticles = function () {
            var i = self.particles.length;
            while (i--) {
              var p = self.particles[i];
              p.draw();
            };
          };
        
          /*=============================================================================*/
          /* Firework Constructor
          /*=============================================================================*/
          var Firework = function (startX, startY, targetX, targetY) {
            this.x = startX;
            this.y = startY;
            this.startX = startX;
            this.startY = startY;
            this.hitX = false;
            this.hitY = false;
            this.coordLast = [
            { x: startX, y: startY },
            { x: startX, y: startY },
            { x: startX, y: startY }];
        
            this.targetX = targetX;
            this.targetY = targetY;
            this.speed = self.fworkSpeed;
            this.angle = Math.atan2(targetY - startY, targetX - startX);
            this.shockwaveAngle = Math.atan2(targetY - startY, targetX - startX) + 90 * (Math.PI / 180);
            this.acceleration = self.fworkAccel / 100;
            this.hue = self.currentHue;
            this.brightness = rand(50, 80);
            this.alpha = rand(50, 100) / 100;
            this.lineWidth = self.lineWidth;
            this.targetRadius = 1;
          };
        
          Firework.prototype.update = function (index) {
            self.ctx.lineWidth = this.lineWidth;
        
            vx = Math.cos(this.angle) * this.speed,
            vy = Math.sin(this.angle) * this.speed;
            this.speed *= 1 + this.acceleration;
            this.coordLast[2].x = this.coordLast[1].x;
            this.coordLast[2].y = this.coordLast[1].y;
            this.coordLast[1].x = this.coordLast[0].x;
            this.coordLast[1].y = this.coordLast[0].y;
            this.coordLast[0].x = this.x;
            this.coordLast[0].y = this.y;
        
            if (self.showTarget) {
              if (this.targetRadius < 8) {
                this.targetRadius += .25;
              } else {
                this.targetRadius = 1;
              }
            }
        
            if (this.startX >= this.targetX) {
              if (this.x + vx <= this.targetX) {
                this.x = this.targetX;
                this.hitX = true;
              } else {
                this.x += vx;
              }
            } else {
              if (this.x + vx >= this.targetX) {
                this.x = this.targetX;
                this.hitX = true;
              } else {
                this.x += vx;
              }
            }
        
            if (this.startY >= this.targetY) {
              if (this.y + vy <= this.targetY) {
                this.y = this.targetY;
                this.hitY = true;
              } else {
                this.y += vy;
              }
            } else {
              if (this.y + vy >= this.targetY) {
                this.y = this.targetY;
                this.hitY = true;
              } else {
                this.y += vy;
              }
            }
        
            if (this.hitX && this.hitY) {
              var randExplosion = rand(0, 9);
              self.createParticles(this.targetX, this.targetY, this.hue);
              self.fireworks.splice(index, 1);
            }
          };
        
          Firework.prototype.draw = function () {
            self.ctx.lineWidth = this.lineWidth;
        
            var coordRand = rand(1, 3) - 1;
            self.ctx.beginPath();
            self.ctx.moveTo(Math.round(this.coordLast[coordRand].x), Math.round(this.coordLast[coordRand].y));
            self.ctx.lineTo(Math.round(this.x), Math.round(this.y));
            self.ctx.closePath();
            self.ctx.strokeStyle = 'hsla(' + this.hue + ', 100%, ' + this.brightness + '%, ' + this.alpha + ')';
            self.ctx.stroke();
        
            if (self.showTarget) {
              self.ctx.save();
              self.ctx.beginPath();
              self.ctx.arc(Math.round(this.targetX), Math.round(this.targetY), this.targetRadius, 0, Math.PI * 2, false);
              self.ctx.closePath();
              self.ctx.lineWidth = 1;
            .........完整代码请登录后点击上方下载按钮下载查看