JavaScript实现时钟滴答声效果

245 阅读 0 评论 162 点赞

我是靠谱客的博主老迟到路灯，这篇文章主要介绍JavaScript实现时钟滴答声效果，现在分享给大家，希望可以做个参考。

下面一段代码给大家分享js实现时钟滴答声功能，具体代码如下所示：

复制代码

<!DOCTYPE html>
<html>
 <head>
 <meta charset="utf8">
 <meta http-equiv="X-UA-Compatible" content="IE=edge, chrome=1">
 <meta name="keywords" content="clock">
 <meta name="description" content="This is a clock">
 <title>Clock</title>
 </head>
 <body>
 <audio id="ticktock">
 <source = src="ticktock.mp3" type="audio/mp3">
 </audio>
 <script type="text/javascript">
 /*
 年(y)可以用 1-4 个占位符
 月(M)、日(d)、时(H,24时)、时(h,12时)、分(m)、秒(s)、季度(q) 可以用 1-2 个占位符
 毫秒(S)只能用 1 个占位符(是 1-3 位数字) 
 AM或PM只能用 1 个占位符(是 2 位英文)
 上午或下午(T)只能用 1 个占位符(是 2 位中文)
 星期(E)可以用 1-3 个占位符
 季度(q)只能用 1 个占位符(是 1 位数字)
 */
 Date.prototype.format = function(fmt) {
 var map = {
  "M+" : this.getMonth() + 1, //月
  "d+" : this.getDate(), //日
  "H+" : this.getHours(), //24时
  /*
  上午12时只代表当天上午的12时,下午的12时代表当天下午的12时,
  0时代表第二天的开始,即前面一天12时已过0时开始计算新一天的时间,
  虽然说时间上跟前面那一天下午12时重合,但日期已经发生更改,所以不能说0时就是12时
  */
  "h+" : this.getHours()%12 == 0 ? 12 : this.getHours()%12,//12时
  "m+" : this.getMinutes(), //分
  "s+" : this.getSeconds(), //秒
  "S" : this.getMilliseconds(), //毫秒
  "t" : this.getHours() < 12 ? "AM" : "PM",
  "T" : this.getHours() < 12 ? "上午" : "下午",
 };
 var week = {
  "0" : "日",
  "1" : "一",
  "2" : "二",
  "3" : "三",
  "4" : "四",
  "5" : "五",
  "6" : "六",
 }
 var quarter = {
  "0" : "一",
  "1" : "二",
  "2" : "三",
  "3" : "四",
 }
 if(/(y+)/.test(fmt)) {
  fmt = fmt.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length));
 }
 if(/(E+)/.test(fmt)) {
  var weekPreStr;
  switch(RegExp.$1.length) {
  case 1:
  weekPreStr = "";
  break;
  case 2:
  weekPreStr = "周";
  break;
  default:
  weekPreStr = "星期";
  break;
  }
  fmt = fmt.replace(RegExp.$1, weekPreStr + week[this.getDay()]);
 }
 if(/(q)/.test(fmt)) {
  fmt = fmt.replace(RegExp.$1, quarter[Math.floor(this.getMonth() / 3)]);
 }
 for(var key in map) {
  if(new RegExp("(" + key + ")").test(fmt)) {
  fmt = fmt.replace(RegExp.$1, RegExp.$1.length == 1 ? map[key] : ("00" + map[key]).substr((map[key]+"").length));
  }
 }
 return fmt;
 }
 </script>
 <script>
 var canvas = document.createElement("canvas");
 document.body.appendChild(canvas);
 var ctx = canvas.getContext("2d");
 var halfPI = Math.PI / 2;
 var doublePI = Math.PI * 2;
 //阴影级别
 var shadowBlur = 10;
 //阴影宽度
 var shadowWidth = 8;
 //阴影在X方向上的偏移
 var shadowOffsetX = 5;
 //阴影在Y方向上的便宜
 var shadowOffsetY = 5;
 //深色阴影
 var shadowDarkColor = "rgba(0,0,0,0.8)";
 //浅色阴影
 var shadowLightColor = "rgba(0,0,0,0.1)";
 //画布中心到边缘的内切圆半径
 var canvasRadius = 250;
 canvas.width = canvasRadius * 2;
 canvas.height = canvasRadius * 2;
 //获取画布中心的坐标
 var cx = canvasRadius;
 var cy = canvasRadius;
 //时钟外圈的贝塞尔花纹个数
 var bezierPatternCount = 36;
 //时钟外圈的贝塞尔花纹波峰处半径
 var bezierPeakRadius = canvasRadius - 10;
 //时钟外圈的贝塞尔花纹一半的角度
 var bezierHalfSpan = doublePI / bezierPatternCount / 2;
 //时钟外圈的贝塞尔花纹底部半径
 var bezierRadius = bezierPeakRadius - 20;
 //时钟外圈的贝塞尔花纹颜色
 var bezierPatternColor = "Plum";
 //时钟外圈半径
 var clockBorderRadius = bezierRadius - 10;
 //时钟外圈宽度
 var clockBorderWidth = 10;
 //时钟外圈颜色
 var clockBorderColor = "Aqua";
 //时钟外圈阴影半径
 var clockBorderShadowRadius = clockBorderRadius - shadowWidth + 1;
 //时钟整数时间刻度线宽
 var clockScaleWidth = 2;
 //时钟整数时间刻度外半径
 var clockScaleOuterRadius = clockBorderRadius - shadowWidth;
 //时钟整数时间刻度内半径
 var clockScaleInnerRadius = clockScaleOuterRadius - 20;
 //时钟刻度颜色
 var clockScaleColor = "Black";
 //时钟非整数时间处半径
 var clockScaleMiddleRadius = clockScaleOuterRadius - 10;
 //时钟数字半径
 var clockNumRadius = clockBorderShadowRadius - 40;
 //时钟数字字体
 var clockNumFont = "25px Arial";
 //时钟数字颜色
 var clockNumColor = "black";
 //数字日期距中心的垂直距离
 var digitalDateMarginCenter = 50;
 //数字日期颜色
 var digitalDateColor = "Black";
 //数字日期字体
 var digitalDateFont = "bold 18px Arial";
 //数字时间距中心的垂直距离
 var digitalTimeMarginCenter = 100;
 //数字时间颜色
 var digitalTimeColor = "white";
 //数字时间背景颜色
 var digitalTimeBgColor = "DarkSlateBlue";
 //数字时间字体
 var digitalTimeFont = "bold 25px Arial";
 //数字时间高度的一半
 var digitalTimeHeight = 40;
 //数字时间分隔线宽度
 var digitalTimeSpanLineWidth = 2;
 //时钟中心点内圆的半径
 var clockCenterInnerDotRadius = 7;
 //时钟中心点内圆的颜色
 var clockCenterInnerDotColor = "FireBrick";
 //时钟中心点外圆的半径
 var clockCenterOuterDotRadius = 10;
 //时钟中心点外圆的颜色
 var clockCenterOuterDotColor = "Maroon";
 //时针线宽
 var clockNeedleWidth = 5;
 //时针半径
 var clockHourNeedleRadius = clockBorderShadowRadius - 120;
 //时针颜色
 var clockHourNeedleColor = "DarkGreen";
 //分针半径
 var clockMinuteNeedleRadius = clockBorderShadowRadius - 80;
 //分针颜色
 var clockMinuteNeedleColor = "DarkSlateGray";
 //秒针半径
 var clockSecondNeedleRadius = clockBorderShadowRadius - 40;
 //秒针尾部半径
 var clockSecondNeedleBottomRadius = -20;
 //秒针颜色
 var clockSecondNeedleColor = "FireBrick";
 //画圆环
 function strokeCircle(cx, cy, r) {
 ctx.beginPath();
 ctx.arc(cx, cy, r, 0, doublePI);
 ctx.stroke();
 }
 //画圆
 function fillCircle(cx, cy, r) {
 ctx.beginPath();
 ctx.arc(cx, cy, r, 0, doublePI);
 ctx.fill();
 }
 //绘制线条
 function strokeLine(x1, y1, x2, y2) {
 ctx.beginPath();
 ctx.moveTo(x1, y1);
 ctx.lineTo(x2, y2);
 ctx.stroke();
 }
 //根据角度和半径计算圆上相应位置的坐标(最右侧为起始角度,顺时针方向为正)
 function circlePos(cx, cy, theta, radius) {
 var pos = {
  x: cx + radius * Math.cos(theta),
  y: cy + radius * Math.sin(theta),
 };
 return pos;
 }
 //在圆环上绘制刻度线
 function strokeCircleLine(cx, cy, theta, r1, r2) {
 var pos1 = circlePos(cx, cy, theta, r1);
 var pos2 = circlePos(cx, cy, theta, r2);
 strokeLine(pos1.x, pos1.y, pos2.x, pos2.y);
 }
 //设置默认阴影
 function setShadow(type) {
 ctx.lineWidth = shadowWidth;
 ctx.shadowBlur = shadowBlur;
 ctx.shadowOffsetX = shadowOffsetX;
 ctx.shadowOffsetY = shadowOffsetY;
 if(type === 1) {
  ctx.shadowColor = shadowLightColor;
 } else {
  ctx.shadowColor = shadowDarkColor;
 }
 }
 //取消阴影
 function clearShadow() {
 ctx.shadowColor = "rgba(0,0,0,0)";
 ctx.shadowBlur = 0;
 ctx.shadowOffsetX = 0;
 ctx.shadowOffsetY = 0;
 }
 //绘制时钟外圈的贝塞尔花纹
 function renderBezierPattern() {
 ctx.fillStyle = bezierPatternColor;
 ctx.beginPath();
 var theta = 0;
 //由于circlePos是顺时针方向正, 故圈也是顺时针方向
 var beginPos = circlePos(cx, cy, theta, bezierRadius);
 ctx.moveTo(beginPos.x, beginPos.y);
 while(theta < doublePI) {
  //贝塞尔曲线控制点
  var controlTheta = theta + bezierHalfSpan;
  var controlPos = circlePos(cx, cy, controlTheta, bezierPeakRadius);
  //贝塞尔曲线终止点
  var endTheta = controlTheta + bezierHalfSpan;
  var endPos = circlePos(cx, cy, endTheta, bezierRadius);
  ctx.quadraticCurveTo(controlPos.x, controlPos.y, endPos.x, endPos.y);
  theta = endTheta;
 }
 //绘制圆counterclockwise=false, 即默认是顺时针方向
 ctx.arc(cx, cy, clockBorderRadius, 0, doublePI, true);
 //注意: 两个相反方向的路径内部为填充范围
 ctx.fill();
 }
 //绘制时钟边框
 function renderClockBorder() {
 //画外框
 ctx.strokeStyle = clockBorderColor;
 ctx.lineWidth = clockBorderWidth;
 strokeCircle(cx, cy, clockBorderRadius);
 //画外框的内阴影
 ctx.strokeStyle = shadowLightColor;
 setShadow(1);
 strokeCircle(cx, cy, clockBorderShadowRadius);
 clearShadow();
 }
 //绘制时钟圆周上的数字和刻度部分
 function renderClockNums() {
 ctx.textAlign = "center";
 ctx.textBaseline = "middle";
 ctx.font = clockNumFont;
 var span = doublePI / 60;
 for(var i = 1, radian = -halfPI + span; i <= 60; i++, radian += span) {
  if(i % 5 == 0) {
  //绘制刻度
  ctx.strokeStyle = clockScaleColor;
  ctx.lineWidth = clockScaleWidth;
  strokeCircleLine(cx, cy, radian, clockScaleInnerRadius, clockScaleOuterRadius);
  //绘制数字
  var pos = circlePos(cx, cy, radian, clockNumRadius);
  var num = i / 5;
  ctx.fillStyle = clockNumColor;
  ctx.fillText(num, pos.x, pos.y);
  } else {
  ctx.strokeStyle = clockScaleColor;
  ctx.lineWidth = clockScaleWidth;
  strokeCircleLine(cx, cy, radian, clockScaleMiddleRadius, clockScaleOuterRadius);
  }
 }
 }
 //绘制数字时钟
 function renderDigital(date) {
 //绘制日期
 ctx.textAlign = "center";
 ctx.textBaseline = "middle";
 ctx.font = digitalDateFont;
 ctx.fillStyle = digitalDateColor;
 var text = date.format("yyyy年MM月dd日 EEE");
 ctx.fillText(text, cx, cy + digitalDateMarginCenter);
 //绘制时间
 ctx.font = digitalTimeFont;
 text = date.format(" HH mm ss ");
 ctx.fillStyle = digitalTimeBgColor;
 var textWidth = ctx.measureText(text).width;
 var textBgX = cx - textWidth / 2;
 var textBgY = cy + digitalTimeMarginCenter - digitalTimeHeight / 2;
 ctx.fillRect(textBgX, textBgY, textWidth, digitalTimeHeight);
 ctx.fillStyle = digitalTimeColor;
 ctx.fillText(text, cx, cy + digitalTimeMarginCenter);
 //绘制事件中间的分隔线
 ctx.lineWidth = digitalTimeSpanLineWidth;
 ctx.strokeStyle = digitalTimeColor;
 var textSpan = textWidth / 6;
 var leftLineX = cx - textSpan;
 strokeLine(leftLineX, textBgY, leftLineX, textBgY + digitalTimeHeight);
 var rightLineX = cx + textSpan;
 strokeLine(rightLineX, textBgY, rightLineX, textBgY + digitalTimeHeight);
 }
 //绘制时钟中心最下方红点
 function renderClockCenterOuterDot() {
 ctx.fillStyle = clockCenterOuterDotColor;
 fillCircle(cx, cy, clockCenterOuterDotRadius);
 }
 //绘制时钟中心最上方红点
 function renderClockCenterInnerDot() {
 ctx.fillStyle = clockCenterInnerDotColor;
 fillCircle(cx, cy, clockCenterInnerDotRadius);
 }
 //绘制时钟指针
 function renderClockNeedle(date) {
 var hourRadian = date.getHours() % 12 / 12 * doublePI - halfPI;
 var minuteRadian = date.getMinutes() / 60 * doublePI - halfPI;
 var secondRadian = date.getSeconds() / 60 * doublePI - halfPI;
 setShadow();
 ctx.lineCap = "round";
 ctx.lineWidth = clockNeedleWidth;
 ctx.strokeStyle = clockHourNeedleColor;
 strokeCircleLine(cx, cy, hourRadian, 0, clockHourNeedleRadius);
 ctx.strokeStyle = clockMinuteNeedleColor;
 strokeCircleLine(cx, cy, minuteRadian, 0, clockMinuteNeedleRadius);
 ctx.strokeStyle = clockSecondNeedleColor;
 strokeCircleLine(cx, cy, secondRadian, clockSecondNeedleBottomRadius, clockSecondNeedleRadius);
 ctx.lineCap = "square";
 clearShadow();
 }
 function render(date) {
 ctx.clearRect(0, 0, canvas.width, canvas.height);
 renderBezierPattern();
 renderClockBorder();
 renderClockNums();
 renderDigital(date);
 renderClockCenterOuterDot();
 renderClockNeedle(date);
 renderClockCenterInnerDot();
 }
 var lastTime = 0;
 var audio = document.getElementById("ticktock");
 function loop() {
 var date = new Date();
 var currentTime = date.getTime();
 if(currentTime - lastTime >= 1000) {
  lastTime = currentTime;
  //注意：这里设0非常关键，否则虽然会循环播放，但会从上一次暂停的地方开始播放，造成延迟
  audio.currentTime = 0;
  audio.play();
  render(date);
 }
 requestAnimationFrame(loop);
 }
 loop();
 </script>
 </body>
</html>

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
<!DOCTYPE html>
<html>
 <head>
 <meta charset="utf8">
 <meta http-equiv="X-UA-Compatible" content="IE=edge, chrome=1">
 <meta name="keywords" content="clock">
 <meta name="description" content="This is a clock">
 <title>Clock</title>
 </head>
 <body>
 <audio id="ticktock">
 <source = src="ticktock.mp3" type="audio/mp3">
 </audio>
 <script type="text/javascript">
 /*
 年(y)可以用 1-4 个占位符
 月(M)、日(d)、时(H,24时)、时(h,12时)、分(m)、秒(s)、季度(q) 可以用 1-2 个占位符
 毫秒(S)只能用 1 个占位符(是 1-3 位数字) 
 AM或PM只能用 1 个占位符(是 2 位英文)
 上午或下午(T)只能用 1 个占位符(是 2 位中文)
 星期(E)可以用 1-3 个占位符
 季度(q)只能用 1 个占位符(是 1 位数字)
 */
 Date.prototype.format = function(fmt) {
 var map = {
  "M+" : this.getMonth() + 1, //月
  "d+" : this.getDate(), //日
  "H+" : this.getHours(), //24时
  /*
  上午12时只代表当天上午的12时,下午的12时代表当天下午的12时,
  0时代表第二天的开始,即前面一天12时已过0时开始计算新一天的时间,
  虽然说时间上跟前面那一天下午12时重合,但日期已经发生更改,所以不能说0时就是12时
  */
  "h+" : this.getHours()%12 == 0 ? 12 : this.getHours()%12,//12时
  "m+" : this.getMinutes(), //分
  "s+" : this.getSeconds(), //秒
  "S" : this.getMilliseconds(), //毫秒
  "t" : this.getHours() < 12 ? "AM" : "PM",
  "T" : this.getHours() < 12 ? "上午" : "下午",
 };
 var week = {
  "0" : "日",
  "1" : "一",
  "2" : "二",
  "3" : "三",
  "4" : "四",
  "5" : "五",
  "6" : "六",
 }
 var quarter = {
  "0" : "一",
  "1" : "二",
  "2" : "三",
  "3" : "四",
 }
 if(/(y+)/.test(fmt)) {
  fmt = fmt.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length));
 }
 if(/(E+)/.test(fmt)) {
  var weekPreStr;
  switch(RegExp.$1.length) {
  case 1:
  weekPreStr = "";
  break;
  case 2:
  weekPreStr = "周";
  break;
  default:
  weekPreStr = "星期";
  break;
  }
  fmt = fmt.replace(RegExp.$1, weekPreStr + week[this.getDay()]);
 }
 if(/(q)/.test(fmt)) {
  fmt = fmt.replace(RegExp.$1, quarter[Math.floor(this.getMonth() / 3)]);
 }
 for(var key in map) {
  if(new RegExp("(" + key + ")").test(fmt)) {
  fmt = fmt.replace(RegExp.$1, RegExp.$1.length == 1 ? map[key] : ("00" + map[key]).substr((map[key]+"").length));
  }
 }
 return fmt;
 }
 </script>
 <script>
 var canvas = document.createElement("canvas");
 document.body.appendChild(canvas);
 var ctx = canvas.getContext("2d");
 var halfPI = Math.PI / 2;
 var doublePI = Math.PI * 2;
 //阴影级别
 var shadowBlur = 10;
 //阴影宽度
 var shadowWidth = 8;
 //阴影在X方向上的偏移
 var shadowOffsetX = 5;
 //阴影在Y方向上的便宜
 var shadowOffsetY = 5;
 //深色阴影
 var shadowDarkColor = "rgba(0,0,0,0.8)";
 //浅色阴影
 var shadowLightColor = "rgba(0,0,0,0.1)";
 //画布中心到边缘的内切圆半径
 var canvasRadius = 250;
 canvas.width = canvasRadius * 2;
 canvas.height = canvasRadius * 2;
 //获取画布中心的坐标
 var cx = canvasRadius;
 var cy = canvasRadius;
 //时钟外圈的贝塞尔花纹个数
 var bezierPatternCount = 36;
 //时钟外圈的贝塞尔花纹波峰处半径
 var bezierPeakRadius = canvasRadius - 10;
 //时钟外圈的贝塞尔花纹一半的角度
 var bezierHalfSpan = doublePI / bezierPatternCount / 2;
 //时钟外圈的贝塞尔花纹底部半径
 var bezierRadius = bezierPeakRadius - 20;
 //时钟外圈的贝塞尔花纹颜色
 var bezierPatternColor = "Plum";
 //时钟外圈半径
 var clockBorderRadius = bezierRadius - 10;
 //时钟外圈宽度
 var clockBorderWidth = 10;
 //时钟外圈颜色
 var clockBorderColor = "Aqua";
 //时钟外圈阴影半径
 var clockBorderShadowRadius = clockBorderRadius - shadowWidth + 1;
 //时钟整数时间刻度线宽
 var clockScaleWidth = 2;
 //时钟整数时间刻度外半径
 var clockScaleOuterRadius = clockBorderRadius - shadowWidth;
 //时钟整数时间刻度内半径
 var clockScaleInnerRadius = clockScaleOuterRadius - 20;
 //时钟刻度颜色
 var clockScaleColor = "Black";
 //时钟非整数时间处半径
 var clockScaleMiddleRadius = clockScaleOuterRadius - 10;
 //时钟数字半径
 var clockNumRadius = clockBorderShadowRadius - 40;
 //时钟数字字体
 var clockNumFont = "25px Arial";
 //时钟数字颜色
 var clockNumColor = "black";
 //数字日期距中心的垂直距离
 var digitalDateMarginCenter = 50;
 //数字日期颜色
 var digitalDateColor = "Black";
 //数字日期字体
 var digitalDateFont = "bold 18px Arial";
 //数字时间距中心的垂直距离
 var digitalTimeMarginCenter = 100;
 //数字时间颜色
 var digitalTimeColor = "white";
 //数字时间背景颜色
 var digitalTimeBgColor = "DarkSlateBlue";
 //数字时间字体
 var digitalTimeFont = "bold 25px Arial";
 //数字时间高度的一半
 var digitalTimeHeight = 40;
 //数字时间分隔线宽度
 var digitalTimeSpanLineWidth = 2;
 //时钟中心点内圆的半径
 var clockCenterInnerDotRadius = 7;
 //时钟中心点内圆的颜色
 var clockCenterInnerDotColor = "FireBrick";
 //时钟中心点外圆的半径
 var clockCenterOuterDotRadius = 10;
 //时钟中心点外圆的颜色
 var clockCenterOuterDotColor = "Maroon";
 //时针线宽
 var clockNeedleWidth = 5;
 //时针半径
 var clockHourNeedleRadius = clockBorderShadowRadius - 120;
 //时针颜色
 var clockHourNeedleColor = "DarkGreen";
 //分针半径
 var clockMinuteNeedleRadius = clockBorderShadowRadius - 80;
 //分针颜色
 var clockMinuteNeedleColor = "DarkSlateGray";
 //秒针半径
 var clockSecondNeedleRadius = clockBorderShadowRadius - 40;
 //秒针尾部半径
 var clockSecondNeedleBottomRadius = -20;
 //秒针颜色
 var clockSecondNeedleColor = "FireBrick";
 //画圆环
 function strokeCircle(cx, cy, r) {
 ctx.beginPath();
 ctx.arc(cx, cy, r, 0, doublePI);
 ctx.stroke();
 }
 //画圆
 function fillCircle(cx, cy, r) {
 ctx.beginPath();
 ctx.arc(cx, cy, r, 0, doublePI);
 ctx.fill();
 }
 //绘制线条
 function strokeLine(x1, y1, x2, y2) {
 ctx.beginPath();
 ctx.moveTo(x1, y1);
 ctx.lineTo(x2, y2);
 ctx.stroke();
 }
 //根据角度和半径计算圆上相应位置的坐标(最右侧为起始角度,顺时针方向为正)
 function circlePos(cx, cy, theta, radius) {
 var pos = {
  x: cx + radius * Math.cos(theta),
  y: cy + radius * Math.sin(theta),
 };
 return pos;
 }
 //在圆环上绘制刻度线
 function strokeCircleLine(cx, cy, theta, r1, r2) {
 var pos1 = circlePos(cx, cy, theta, r1);
 var pos2 = circlePos(cx, cy, theta, r2);
 strokeLine(pos1.x, pos1.y, pos2.x, pos2.y);
 }
 //设置默认阴影
 function setShadow(type) {
 ctx.lineWidth = shadowWidth;
 ctx.shadowBlur = shadowBlur;
 ctx.shadowOffsetX = shadowOffsetX;
 ctx.shadowOffsetY = shadowOffsetY;
 if(type === 1) {
  ctx.shadowColor = shadowLightColor;
 } else {
  ctx.shadowColor = shadowDarkColor;
 }
 }
 //取消阴影
 function clearShadow() {
 ctx.shadowColor = "rgba(0,0,0,0)";
 ctx.shadowBlur = 0;
 ctx.shadowOffsetX = 0;
 ctx.shadowOffsetY = 0;
 }
 //绘制时钟外圈的贝塞尔花纹
 function renderBezierPattern() {
 ctx.fillStyle = bezierPatternColor;
 ctx.beginPath();
 var theta = 0;
 //由于circlePos是顺时针方向正, 故圈也是顺时针方向
 var beginPos = circlePos(cx, cy, theta, bezierRadius);
 ctx.moveTo(beginPos.x, beginPos.y);
 while(theta < doublePI) {
  //贝塞尔曲线控制点
  var controlTheta = theta + bezierHalfSpan;
  var controlPos = circlePos(cx, cy, controlTheta, bezierPeakRadius);
  //贝塞尔曲线终止点
  var endTheta = controlTheta + bezierHalfSpan;
  var endPos = circlePos(cx, cy, endTheta, bezierRadius);
  ctx.quadraticCurveTo(controlPos.x, controlPos.y, endPos.x, endPos.y);
  theta = endTheta;
 }
 //绘制圆counterclockwise=false, 即默认是顺时针方向
 ctx.arc(cx, cy, clockBorderRadius, 0, doublePI, true);
 //注意: 两个相反方向的路径内部为填充范围
 ctx.fill();
 }
 //绘制时钟边框
 function renderClockBorder() {
 //画外框
 ctx.strokeStyle = clockBorderColor;
 ctx.lineWidth = clockBorderWidth;
 strokeCircle(cx, cy, clockBorderRadius);
 //画外框的内阴影
 ctx.strokeStyle = shadowLightColor;
 setShadow(1);
 strokeCircle(cx, cy, clockBorderShadowRadius);
 clearShadow();
 }
 //绘制时钟圆周上的数字和刻度部分
 function renderClockNums() {
 ctx.textAlign = "center";
 ctx.textBaseline = "middle";
 ctx.font = clockNumFont;
 var span = doublePI / 60;
 for(var i = 1, radian = -halfPI + span; i <= 60; i++, radian += span) {
  if(i % 5 == 0) {
  //绘制刻度
  ctx.strokeStyle = clockScaleColor;
  ctx.lineWidth = clockScaleWidth;
  strokeCircleLine(cx, cy, radian, clockScaleInnerRadius, clockScaleOuterRadius);
  //绘制数字
  var pos = circlePos(cx, cy, radian, clockNumRadius);
  var num = i / 5;
  ctx.fillStyle = clockNumColor;
  ctx.fillText(num, pos.x, pos.y);
  } else {
  ctx.strokeStyle = clockScaleColor;
  ctx.lineWidth = clockScaleWidth;
  strokeCircleLine(cx, cy, radian, clockScaleMiddleRadius, clockScaleOuterRadius);
  }
 }
 }
 //绘制数字时钟
 function renderDigital(date) {
 //绘制日期
 ctx.textAlign = "center";
 ctx.textBaseline = "middle";
 ctx.font = digitalDateFont;
 ctx.fillStyle = digitalDateColor;
 var text = date.format("yyyy年MM月dd日 EEE");
 ctx.fillText(text, cx, cy + digitalDateMarginCenter);
 //绘制时间
 ctx.font = digitalTimeFont;
 text = date.format(" HH mm ss ");
 ctx.fillStyle = digitalTimeBgColor;
 var textWidth = ctx.measureText(text).width;
 var textBgX = cx - textWidth / 2;
 var textBgY = cy + digitalTimeMarginCenter - digitalTimeHeight / 2;
 ctx.fillRect(textBgX, textBgY, textWidth, digitalTimeHeight);
 ctx.fillStyle = digitalTimeColor;
 ctx.fillText(text, cx, cy + digitalTimeMarginCenter);
 //绘制事件中间的分隔线
 ctx.lineWidth = digitalTimeSpanLineWidth;
 ctx.strokeStyle = digitalTimeColor;
 var textSpan = textWidth / 6;
 var leftLineX = cx - textSpan;
 strokeLine(leftLineX, textBgY, leftLineX, textBgY + digitalTimeHeight);
 var rightLineX = cx + textSpan;
 strokeLine(rightLineX, textBgY, rightLineX, textBgY + digitalTimeHeight);
 }
 //绘制时钟中心最下方红点
 function renderClockCenterOuterDot() {
 ctx.fillStyle = clockCenterOuterDotColor;
 fillCircle(cx, cy, clockCenterOuterDotRadius);
 }
 //绘制时钟中心最上方红点
 function renderClockCenterInnerDot() {
 ctx.fillStyle = clockCenterInnerDotColor;
 fillCircle(cx, cy, clockCenterInnerDotRadius);
 }
 //绘制时钟指针
 function renderClockNeedle(date) {
 var hourRadian = date.getHours() % 12 / 12 * doublePI - halfPI;
 var minuteRadian = date.getMinutes() / 60 * doublePI - halfPI;
 var secondRadian = date.getSeconds() / 60 * doublePI - halfPI;
 setShadow();
 ctx.lineCap = "round";
 ctx.lineWidth = clockNeedleWidth;
 ctx.strokeStyle = clockHourNeedleColor;
 strokeCircleLine(cx, cy, hourRadian, 0, clockHourNeedleRadius);
 ctx.strokeStyle = clockMinuteNeedleColor;
 strokeCircleLine(cx, cy, minuteRadian, 0, clockMinuteNeedleRadius);
 ctx.strokeStyle = clockSecondNeedleColor;
 strokeCircleLine(cx, cy, secondRadian, clockSecondNeedleBottomRadius, clockSecondNeedleRadius);
 ctx.lineCap = "square";
 clearShadow();
 }
 function render(date) {
 ctx.clearRect(0, 0, canvas.width, canvas.height);
 renderBezierPattern();
 renderClockBorder();
 renderClockNums();
 renderDigital(date);
 renderClockCenterOuterDot();
 renderClockNeedle(date);
 renderClockCenterInnerDot();
 }
 var lastTime = 0;
 var audio = document.getElementById("ticktock");
 function loop() {
 var date = new Date();
 var currentTime = date.getTime();
 if(currentTime - lastTime >= 1000) {
  lastTime = currentTime;
  //注意：这里设0非常关键，否则虽然会循环播放，但会从上一次暂停的地方开始播放，造成延迟
  audio.currentTime = 0;
  audio.play();
  render(date);
 }
 requestAnimationFrame(loop);
 }
 loop();
 </script>
 </body>
</html>