H5页面自动烟花特效

代码如下:

  1 <!DOCTYPE html>
  2 <html>
  3     <head>
  4         <meta charset="utf-8">
  5         <title></title>
  6         <!-- 引用本地jquery文件 -->
  7         <!-- <script src="../js/jquery-1.9.1.min.js"></script> -->
  8         <!-- 引用百度jquery文件 -->
  9         <script src="http://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script>
 10         <style type="text/css">
 11             .divBody {
 12                 position: absolute;
 13                 top: 0;
 14                 left: 0;
 15                  100%;
 16                 height: 100%;
 17                 background-color: #000000;
 18                 font-family: "黑体";
 19                 color: #292929;
 20             }
 21 
 22             canvas {
 23                 cursor: crosshair;
 24                 display: block;
 25                 left: 0;
 26                 position: absolute;
 27                 top: 0;
 28                 z-index: 20;
 29             }
 30         </style>
 31     </head>
 32     <body>
 33         <div class="divBody"></div>
 34         <canvas width="100%" height="100%"></canvas>
 35     </body>
 36 </html>
 37 <script>
 38     var Fireworks;
 39     $(function() {
 40         Fireworks = function() {
 41             var self = this;
 42             var rand = function(rMi, rMa) {
 43                 return ~~((Math.random() * (rMa - rMi + 1)) + rMi);
 44             }
 45             var hitTest = function(x1, y1, w1, h1, x2, y2, w2, h2) {
 46                 return !(x1 + w1 < x2 || x2 + w2 < x1 || y1 + h1 < y2 || y2 + h2 < y1);
 47             };
 48             window.requestAnimFrame = function() {
 49                 return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame ||
 50                     window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(a) {
 51                         window.setTimeout(a, 1E3 / 60)
 52                     }
 53             }();
 54 
 55             self.init = function() {
 56                 self.canvas = document.createElement('canvas');
 57                 self.canvas.width = self.cw = $(window).innerWidth();
 58                 self.canvas.height = self.ch = $(window).innerHeight();
 59                 self.particles = [];
 60                 self.partCount = 150;
 61                 self.fireworks = [];
 62                 self.mx = self.cw / 2;
 63                 self.my = self.ch / 2;
 64                 self.currentHue = 30;
 65                 self.partSpeed = 5;
 66                 self.partSpeedVariance = 10;
 67                 self.partWind = 50;
 68                 self.partFriction = 5;
 69                 self.partGravity = 1;
 70                 self.hueMin = 0;
 71                 self.hueMax = 10; //单次最多释放个数
 72                 self.fworkSpeed = 4;
 73                 self.fworkAccel = 10;
 74                 self.hueVariance = 30;
 75                 self.flickerDensity = 25;
 76                 self.showShockwave = true;
 77                 self.showTarget = false;
 78                 self.clearAlpha = 25;
 79 
 80                 $(document.body).append(self.canvas);
 81                 self.ctx = self.canvas.getContext('2d');
 82                 self.ctx.lineCap = 'round';
 83                 self.ctx.lineJoin = 'round';
 84                 self.lineWidth = 1;
 85                 self.bindEvents();
 86                 self.canvasLoop();
 87 
 88                 self.canvas.onselectstart = function() {
 89                     return false;
 90                 };
 91             };
 92 
 93             self.createParticles = function(x, y, hue) {
 94                 var countdown = self.partCount;
 95                 while (countdown--) {
 96                     var newParticle = {
 97                         x: x,
 98                         y: y,
 99                         coordLast: [{
100                                 x: x,
101                                 y: y
102                             },
103                             {
104                                 x: x,
105                                 y: y
106                             },
107                             {
108                                 x: x,
109                                 y: y
110                             }
111                         ],
112                         angle: rand(0, 360),
113                         speed: rand(((self.partSpeed - self.partSpeedVariance) <= 0) ? 1 : self.partSpeed - self.partSpeedVariance,
114                             (self.partSpeed + self.partSpeedVariance)),
115                         friction: 1 - self.partFriction / 100,
116                         gravity: self.partGravity / 2,
117                         hue: rand(hue - self.hueVariance, hue + self.hueVariance),
118                         brightness: rand(50, 80),
119                         alpha: rand(40, 100) / 100,
120                         decay: rand(10, 50) / 1000,
121                         wind: (rand(0, self.partWind) - (self.partWind / 2)) / 25,
122                         lineWidth: self.lineWidth
123                     };
124                     self.particles.push(newParticle);
125                 }
126             };
127 
128 
129             self.updateParticles = function() {
130                 var i = self.particles.length;
131                 while (i--) {
132                     var p = self.particles[i];
133                     var radians = p.angle * Math.PI / 180;
134                     var vx = Math.cos(radians) * p.speed;
135                     var vy = Math.sin(radians) * p.speed;
136                     p.speed *= p.friction;
137 
138                     p.coordLast[2].x = p.coordLast[1].x;
139                     p.coordLast[2].y = p.coordLast[1].y;
140                     p.coordLast[1].x = p.coordLast[0].x;
141                     p.coordLast[1].y = p.coordLast[0].y;
142                     p.coordLast[0].x = p.x;
143                     p.coordLast[0].y = p.y;
144 
145                     p.x += vx;
146                     p.y += vy;
147                     p.y += p.gravity;
148 
149                     p.angle += p.wind;
150                     p.alpha -= p.decay;
151 
152                     if (!hitTest(0, 0, self.cw, self.ch, p.x - p.radius, p.y - p.radius, p.radius * 2, p.radius * 2) || p.alpha <
153                         .05) {
154                         self.particles.splice(i, 1);
155                     }
156                 };
157             };
158 
159             self.drawParticles = function() {
160                 var i = self.particles.length;
161                 while (i--) {
162                     var p = self.particles[i];
163 
164                     var coordRand = (rand(1, 3) - 1);
165                     self.ctx.beginPath();
166                     self.ctx.moveTo(Math.round(p.coordLast[coordRand].x), Math.round(p.coordLast[coordRand].y));
167                     self.ctx.lineTo(Math.round(p.x), Math.round(p.y));
168                     self.ctx.closePath();
169                     self.ctx.strokeStyle = 'hsla(' + p.hue + ', 100%, ' + p.brightness + '%, ' + p.alpha + ')';
170                     self.ctx.stroke();
171 
172                     if (self.flickerDensity > 0) {
173                         var inverseDensity = 50 - self.flickerDensity;
174                         if (rand(0, inverseDensity) === inverseDensity) {
175                             self.ctx.beginPath();
176                             self.ctx.arc(Math.round(p.x), Math.round(p.y), rand(p.lineWidth, p.lineWidth + 3) / 2, 0, Math.PI * 2, false)
177                             self.ctx.closePath();
178                             var randAlpha = rand(50, 100) / 100;
179                             self.ctx.fillStyle = 'hsla(' + p.hue + ', 100%, ' + p.brightness + '%, ' + randAlpha + ')';
180                             self.ctx.fill();
181                         }
182                     }
183                 };
184             };
185 
186 
187             self.createFireworks = function(startX, startY, targetX, targetY) {
188                 var newFirework = {
189                     x: startX,
190                     y: startY,
191                     startX: startX,
192                     startY: startY,
193                     hitX: false,
194                     hitY: false,
195                     coordLast: [{
196                             x: startX,
197                             y: startY
198                         },
199                         {
200                             x: startX,
201                             y: startY
202                         },
203                         {
204                             x: startX,
205                             y: startY
206                         }
207                     ],
208                     targetX: targetX,
209                     targetY: targetY,
210                     speed: self.fworkSpeed,
211                     angle: Math.atan2(targetY - startY, targetX - startX),
212                     shockwaveAngle: Math.atan2(targetY - startY, targetX - startX) + (90 * (Math.PI / 180)),
213                     acceleration: self.fworkAccel / 100,
214                     hue: self.currentHue,
215                     brightness: rand(50, 80),
216                     alpha: rand(50, 100) / 100,
217                     lineWidth: self.lineWidth
218                 };
219                 if (self.fireworks.length < self.hueMax) {
220                     self.fireworks.push(newFirework);
221                 }
222 
223 
224             };
225 
226 
227             self.updateFireworks = function() {
228                 var i = self.fireworks.length;
229 
230                 while (i--) {
231                     var f = self.fireworks[i];
232                     self.ctx.lineWidth = f.lineWidth;
233 
234                     vx = Math.cos(f.angle) * f.speed,
235                         vy = Math.sin(f.angle) * f.speed;
236                     f.speed *= 1 + f.acceleration;
237                     f.coordLast[2].x = f.coordLast[1].x;
238                     f.coordLast[2].y = f.coordLast[1].y;
239                     f.coordLast[1].x = f.coordLast[0].x;
240                     f.coordLast[1].y = f.coordLast[0].y;
241                     f.coordLast[0].x = f.x;
242                     f.coordLast[0].y = f.y;
243 
244                     if (f.startX >= f.targetX) {
245                         if (f.x + vx <= f.targetX) {
246                             f.x = f.targetX;
247                             f.hitX = true;
248                         } else {
249                             f.x += vx;
250                         }
251                     } else {
252                         if (f.x + vx >= f.targetX) {
253                             f.x = f.targetX;
254                             f.hitX = true;
255                         } else {
256                             f.x += vx;
257                         }
258                     }
259 
260                     if (f.startY >= f.targetY) {
261                         if (f.y + vy <= f.targetY) {
262                             f.y = f.targetY;
263                             f.hitY = true;
264                         } else {
265                             f.y += vy;
266                         }
267                     } else {
268                         if (f.y + vy >= f.targetY) {
269                             f.y = f.targetY;
270                             f.hitY = true;
271                         } else {
272                             f.y += vy;
273                         }
274                     }
275 
276                     if (f.hitX && f.hitY) {
277                         self.createParticles(f.targetX, f.targetY, f.hue);
278                         self.fireworks.splice(i, 1);
279 
280                     }
281                 };
282             };
283 
284             self.drawFireworks = function() {
285                 var i = self.fireworks.length;
286                 self.ctx.globalCompositeOperation = 'lighter';
287                 while (i--) {
288                     var f = self.fireworks[i];
289                     self.ctx.lineWidth = f.lineWidth;
290 
291                     var coordRand = (rand(1, 3) - 1);
292                     self.ctx.beginPath();
293                     self.ctx.moveTo(Math.round(f.coordLast[coordRand].x), Math.round(f.coordLast[coordRand].y));
294                     self.ctx.lineTo(Math.round(f.x), Math.round(f.y));
295                     self.ctx.closePath();
296                     self.ctx.strokeStyle = 'hsla(' + f.hue + ', 100%, ' + f.brightness + '%, ' + f.alpha + ')';
297                     self.ctx.stroke();
298 
299                     if (self.showTarget) {
300                         self.ctx.save();
301                         self.ctx.beginPath();
302                         self.ctx.arc(Math.round(f.targetX), Math.round(f.targetY), rand(1, 8), 0, Math.PI * 2, false)
303                         self.ctx.closePath();
304                         self.ctx.lineWidth = 1;
305                         self.ctx.stroke();
306                         self.ctx.restore();
307                     }
308 
309                     if (self.showShockwave) {
310                         self.ctx.save();
311                         self.ctx.translate(Math.round(f.x), Math.round(f.y));
312                         self.ctx.rotate(f.shockwaveAngle);
313                         self.ctx.beginPath();
314                         self.ctx.arc(0, 0, 1 * (f.speed / 5), 0, Math.PI, true);
315                         self.ctx.strokeStyle = 'hsla(' + f.hue + ', 100%, ' + f.brightness + '%, ' + rand(25, 60) / 100 + ')';
316                         self.ctx.lineWidth = f.lineWidth;
317                         self.ctx.stroke();
318                         self.ctx.restore();
319                     }
320                 };
321             };
322 
323             self.bindEvents = function() {
324                 $(window).on('resize', function() {
325                     clearTimeout(self.timeout);
326                     self.timeout = setTimeout(function() {
327                         self.canvas.width = self.cw = $(window).innerWidth();
328                         self.canvas.height = self.ch = $(window).innerHeight();
329                         self.ctx.lineCap = 'round';
330                         self.ctx.lineJoin = 'round';
331                     }, 100);
332                 });
333                 //鼠标点击释放烟花
334                 $(self.canvas).on('mousedown', function(e) {
335                     self.mx = e.pageX - self.canvas.offsetLeft;
336                     self.my = e.pageY - self.canvas.offsetTop;
337                     self.currentHue = rand(self.hueMin, self.hueMax);
338                     self.createFireworks(self.cw / 2, self.ch, self.mx, self.my);
339 
340                     $(self.canvas).on('mousemove.fireworks', function(e) {
341                         self.mx = e.pageX - self.canvas.offsetLeft;
342                         self.my = e.pageY - self.canvas.offsetTop;
343                         self.currentHue = rand(self.hueMin, self.hueMax);
344                         self.createFireworks(self.cw / 2, self.ch, self.mx, self.my);
345                     });
346                 });
347 
348                 $(self.canvas).on('mouseup', function(e) {
349                     $(self.canvas).off('mousemove.fireworks');
350                 });
351 
352             }
353 
354             self.clear = function() {
355                 self.particles = [];
356                 self.fireworks = [];
357                 self.ctx.clearRect(0, 0, self.cw, self.ch);
358             };
359 
360 
361             self.canvasLoop = function() {
362                 requestAnimFrame(self.canvasLoop, self.canvas);
363                 self.ctx.globalCompositeOperation = 'destination-out';
364                 self.ctx.fillStyle = 'rgba(0,0,0,' + self.clearAlpha / 100 + ')';
365                 self.ctx.fillRect(0, 0, self.cw, self.ch);
366                 self.updateFireworks();
367                 self.updateParticles();
368                 self.drawFireworks();
369                 self.drawParticles();
370 
371             };
372 
373             self.testClick = function() {
374                 var eventX = randomNum(0, width);
375                 var eventY = randomNum(0, height);
376                 self.mx = eventX;
377                 self.my = eventY;
378                 self.currentHue = rand(self.hueMin, self.hueMax);
379                 self.createFireworks(self.cw / 2, self.ch, self.mx, self.my);
380             };
381 
382             self.setInterval = function() {
383                 setTimeout(function() {
384                     self.testClick();
385                     clearTimeout(self.timeout);
386                     setTimeout(function() {
387                         self.setInterval();
388                     }, 1000);
389                 }, 1000);
390 
391 
392 
393             };
394 
395             self.init();
396             self.setInterval(); //PS:页面加载后自动执行
397 
398         }
399         var fworks = new Fireworks();
400 
401     });
402 
403 
404     var width = $(window).width();
405     var height = $(window).height();
406     //获取随机数 生成坐标
407     function randomNum(minNum, maxNum) {
408         switch (arguments.length) {
409             case 1:
410                 return parseInt(Math.random() * minNum + 1, 10);
411                 break;
412             case 2:
413                 return parseInt(Math.random() * (maxNum - minNum + 1) + minNum, 10);
414                 break;
415             default:
416                 return 0;
417                 break;
418         }
419     }
420 </script>
原文地址:https://www.cnblogs.com/xy0710/p/14029530.html