-
Notifications
You must be signed in to change notification settings - Fork 3
/
globe.js
6148 lines (5487 loc) · 444 KB
/
globe.js
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
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/**
* @file WebGL 3D地球
* @author vision <[email protected]>
*/
(function (window, document) {
/**
* 项目URL根目录,用于加载资源,注意,这个-8是'globe.js'的长度
* @const
* @type {string}
*/
var URL_ROOT = document.currentScript.src.slice(0, -8);
/**
* 数组的constructor
* @const
* @type {Array}
*/
var ARRAY = Array;
/**
* 数组的prototype
* @const
* @type {Object}
*/
var ARRAY_PROTOTYPE = ARRAY.prototype;
/**
* 对象的constructor
* @const
* @type {Object}
*/
var OBJECT = Object;
/**
* 对象的prototype
* @const
* @type {Object}
*/
var OBJECT_PROTOTYPE = OBJECT.prototype;
/**
* Float32Array
* @const
* @type {Function}
*/
var FLOAT32_ARRAY = Float32Array ? Float32Array : ARRAY;
/**
* Math对象
* @const
* @type {Object}
*/
var MATH = Math;
/**
* Math.PI常量
* @const
* @type {number}
*/
var MATH_PI = MATH.PI;
/**
* Math.random函数
* @const
* @type {Function}
*/
var MATH_RANDOM = MATH.random;
/**
* Math.sin函数
* @const
* @type {Function}
*/
var MATH_SIN = MATH.sin;
/**
* Math.cos函数
* @const
* @type {Function}
*/
var MATH_COS = MATH.cos;
/**
* Math.sqrt函数
* @const
* @type {Function}
*/
var MATH_SQRT = MATH.sqrt;
/**
* Math.pow函数
* @const
* @type {Function}
*/
var MATH_POW = MATH.pow;
/**
* Math.max函数
* @const
* @type {Function}
*/
var MATH_MAX = MATH.max;
/**
* Math.min函数
* @const
* @type {Function}
*/
var MATH_MIN = MATH.min;
/**
* 标记鼠标当前坐标,包括移动
* @type {number[]}
*/
var MOUSE_POS = [0, 0];
/**
* 标记鼠标按下状态
* -1 没有按下
* 0 鼠标左键按下
* 2 鼠标右键按下
* @type {number}
*/
var MOUSE_DOWN = -1;
/**
* 标记鼠标上次按下的坐标
* @type {number[]}
*/
var MOUSE_DOWN_POS = [0, 0];
/**
* 标记鼠标上次按下的时间
* @type {number}
*/
var MOUSE_DOWN_TIME = 0;
/**
* 标记是否正在拖拽
* @type {boolean}
*/
var MOUSE_DRAGGING = false;
/**
* 获取一个资源的链接
* @param path
* @returns {string}
*/
function resource(path) {
return URL_ROOT + path;
}
/**
* 判断变量是否是数组
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isArray(obj) {
return OBJECT_PROTOTYPE.toString.call(obj) === "[object Array]";
}
/**
* 判断变量是否是对象
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isObject(obj) {
return !(OBJECT_PROTOTYPE.toString.call(obj) !== "[object Object]" || isDom(obj) || obj instanceof Window);
}
/**
* 判断变量是否是字符串
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isString(obj) {
return typeof obj === "string";
}
/**
* 判断变量是否是函数
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isFunction(obj) {
return typeof obj === "function";
}
/**
* 判断变量是否是数值,包括整型,浮点型,和数值型的字符串
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isNumeric(obj) {
return !isArray(obj) && (obj - parseFloat(obj) + 1) >= 0;
}
/**
* 判断变量是否是undefine或null
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isNull(obj) {
return obj === undefined || obj === null;
}
/**
* 判断变量是否是DOM(HTMLElement)
* @param {*} obj 要判断的变量
* @returns {boolean}
*/
function isDom(obj) {
return obj instanceof HTMLElement;
}
/**
* 构建类之间的继承关系
* @param {Function} subClass 子类函数
* @param {Function} superClass 父类函数
*/
function inherits(subClass, superClass) {
var F = new Function();
var prototype = clone(subClass.prototype);
F.prototype = superClass.prototype;
subClass.prototype = new F();
extend(true, subClass.prototype, prototype);
subClass.prototype.constructor = subClass;
}
/**
* 遍历一个对象或数组
* @param obj 对象或数组
* @param cb 回调函数
* @param context
*/
function each(obj, cb, context) {
if (!(obj && cb)) {
return;
}
context = context || obj;
//优先使用forEach,针对数组
if (obj.forEach && obj.forEach === ARRAY_PROTOTYPE.forEach) {
obj.forEach(cb, context);
}
//针对函数
else if (!isFunction(obj) && obj.length === +obj.length) {
for (var i = 0, len = obj.length; i < len; i++) {
cb.call(context, obj[i], i, obj);
}
}
else {
//遍历对象
var i = 0;
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
cb.call(context, obj[key], key, obj, i);
i++;
}
}
}
}
window.each = each;
/**
* 深度克隆一个变量
* @param source
* @returns {*}
*/
function clone(source) {
//如果是对象,深度克隆
if (isObject(source)) {
var result = source;
//如果是数组,length遍历法
if (isArray(source)) {
result = [];
for (var i = 0, len = source.length; i < len; i++) {
result[i] = clone(source[i]);
}
} else {
//如果是对象,属性遍历法
result = {};
for (var key in source) {
if (source.hasOwnProperty(key)) {
//深度克隆
result[key] = clone(source[key]);
}
}
}
return result;
}
return source;
}
/**
* 深度合并多个对象(继承)
* @returns {*|{}}
*/
function extend() {
var src, copyIsArray, copy, name, options, clone,
target = arguments[0] || {},
i = 1,
length = arguments.length,
deep = false;
//第一个值是布尔,代表是否深度合并
if (typeof target === "boolean") {
deep = target;
target = arguments[i] || {};
i++;
}
//如果目标对象不是对象或函数,默认生成一个空对象
if (typeof target !== "object" && !isFunction(target)) {
target = {};
}
if (i === length) {
target = this;
i--;
}
//逐一合并,越往后优先级越高
for (; i < length; i++) {
if ((options = arguments[i]) != null) {
for (name in options) {
src = target[name];
copy = options[name];
if (target === copy) {
continue;
}
if (deep && copy && ( isObject(copy) || (copyIsArray = isArray(copy)) )) {
if (copyIsArray) {
copyIsArray = false;
clone = src && isArray(src) ? src : [];
} else {
clone = src && isObject(src) ? src : {};
}
//深度合并
target[name] = extend(deep, clone, copy);
} else if (copy !== undefined) {
target[name] = copy;
}
}
}
}
return target;
}
/**
* 批量向一个数组push元素
* @param array
*/
function arrayPush(array) {
for (var t = 1; t < arguments.length; ++t) {
array.push.apply(array, arguments[t])
}
}
/**
* 获取一个对象的所有key
* @param obj
* @returns {Array}
*/
function keys(obj) {
var keys = [];
for (var i in obj) {
keys.push(i);
}
return keys;
}
/**
* 回调一个函数,最后一个参数是context
* @param callback
*/
function caller(callback) {
var args = arguments,
context = args.length == 1 ? null : args[args.length - 1],
params = ARRAY_PROTOTYPE.slice.call(args, 1, args.length - 1);
//执行回调
if (isFunction(callback)) {
callback.apply(context, params);
}
return context;
}
/**
* 代理函数
* @param fn
* @param context
* @returns {*}
*/
function proxy(fn, context) {
var args;
if (!isFunction(fn)) {
return undefined;
}
args = ARRAY_PROTOTYPE.slice.call(arguments, 2);
return function () {
return fn.apply(context || this, args.concat(ARRAY_PROTOTYPE.slice.call(arguments)));
};
}
/**
* 从参数列表中挑选一个可用的值
* @returns {*}
*/
function pick() {
var args = arguments;
for (var i in args) {
if (typeof args[i] != "undefined" && args[i] !== null) {
return args[i];
}
}
}
var triangulateShape = (function () {
/**
* 返回两条线段的交点.
* @param inSeg1Pt1 要检查交点的第一条线的起始点
* @param inSeg1Pt2 要检查交点的第一条线的结束点
* @param inSeg2Pt1 要检查交点的第二条线的起始点
* @param inSeg2Pt2 要检查交点的第二条线的结束点
* @param inExcludeAdjacentSegs 是否排除相邻的线段
* @returns {*}
*/
function intersectSegments2D(inSeg1Pt1, inSeg1Pt2, inSeg2Pt1, inSeg2Pt2, inExcludeAdjacentSegs) {
var seg1dx = inSeg1Pt2[0] - inSeg1Pt1[0], seg1dy = inSeg1Pt2[1] - inSeg1Pt1[1];
var seg2dx = inSeg2Pt2[0] - inSeg2Pt1[0], seg2dy = inSeg2Pt2[1] - inSeg2Pt1[1];
var seg1seg2dx = inSeg1Pt1[0] - inSeg2Pt1[0];
var seg1seg2dy = inSeg1Pt1[1] - inSeg2Pt1[1];
var limit = seg1dy * seg2dx - seg1dx * seg2dy;
var perpSeg1 = seg1dy * seg1seg2dx - seg1dx * seg1seg2dy;
if (Math.abs(limit) > Number.EPSILON) {
//两条线不平行
var perpSeg2;
if (limit > 0) {
if (( perpSeg1 < 0 ) || ( perpSeg1 > limit )) return [];
perpSeg2 = seg2dy * seg1seg2dx - seg2dx * seg1seg2dy;
if (( perpSeg2 < 0 ) || ( perpSeg2 > limit )) return [];
} else {
if (( perpSeg1 > 0 ) || ( perpSeg1 < limit )) return [];
perpSeg2 = seg2dy * seg1seg2dx - seg2dx * seg1seg2dy;
if (( perpSeg2 > 0 ) || ( perpSeg2 < limit )) return [];
}
// 交点位于第一条线的端点
if (perpSeg2 === 0) {
if (( inExcludeAdjacentSegs ) &&
( ( perpSeg1 === 0 ) || ( perpSeg1 === limit ) )) return [];
return [inSeg1Pt1];
}
if (perpSeg2 === limit) {
if (( inExcludeAdjacentSegs ) &&
( ( perpSeg1 === 0 ) || ( perpSeg1 === limit ) )) return [];
return [inSeg1Pt2];
}
// 交点位于第二条线的端点
if (perpSeg1 === 0) return [inSeg2Pt1];
if (perpSeg1 === limit) return [inSeg2Pt2];
// 返回真正的交点
var factorSeg1 = perpSeg2 / limit;
return [
{
x: inSeg1Pt1[0] + factorSeg1 * seg1dx,
y: inSeg1Pt1[1] + factorSeg1 * seg1dy
}
];
} else {
// 返回真正的交点
if (( perpSeg1 !== 0 ) ||
( seg2dy * seg1seg2dx !== seg2dx * seg1seg2dy )) return [];
// 两条线共线或无效
var seg1Pt = ( ( seg1dx === 0 ) && ( seg1dy === 0 ) ); // 第一条线只是一个点
var seg2Pt = ( ( seg2dx === 0 ) && ( seg2dy === 0 ) ); // 第二条线只是一个点
// 两条线都是点
if (seg1Pt && seg2Pt) {
if (( inSeg1Pt1[0] !== inSeg2Pt1[0] ) ||
( inSeg1Pt1[1] !== inSeg2Pt1[1] )) return []; // 两个点不共点,返回空数组
return [inSeg1Pt1]; // 共点
}
// 第一条线段是一个点
if (seg1Pt) {
if (!pointInSegment2DColin(inSeg2Pt1, inSeg2Pt2, inSeg1Pt1)) return []; // 不在第二条线段内,返回空数组
return [inSeg1Pt1];
}
// 第二条线段是一个点
if (seg2Pt) {
if (!pointInSegment2DColin(inSeg1Pt1, inSeg1Pt2, inSeg2Pt1)) return []; // 不在第一条线段内,返回空数组
return [inSeg2Pt1];
}
// 两条线共线,有可能重叠.
var seg1min, seg1max, seg1minVal, seg1maxVal;
var seg2min, seg2max, seg2minVal, seg2maxVal;
if (seg1dx !== 0) {
// 线不是垂直的线
if (inSeg1Pt1[0] < inSeg1Pt2[0]) {
seg1min = inSeg1Pt1;
seg1minVal = inSeg1Pt1[0];
seg1max = inSeg1Pt2;
seg1maxVal = inSeg1Pt2[0];
} else {
seg1min = inSeg1Pt2;
seg1minVal = inSeg1Pt2[0];
seg1max = inSeg1Pt1;
seg1maxVal = inSeg1Pt1[0];
}
if (inSeg2Pt1[0] < inSeg2Pt2[0]) {
seg2min = inSeg2Pt1;
seg2minVal = inSeg2Pt1[0];
seg2max = inSeg2Pt2;
seg2maxVal = inSeg2Pt2[0];
} else {
seg2min = inSeg2Pt2;
seg2minVal = inSeg2Pt2[0];
seg2max = inSeg2Pt1;
seg2maxVal = inSeg2Pt1[0];
}
} else {
// 是一个垂直的线
if (inSeg1Pt1[1] < inSeg1Pt2[1]) {
seg1min = inSeg1Pt1;
seg1minVal = inSeg1Pt1[1];
seg1max = inSeg1Pt2;
seg1maxVal = inSeg1Pt2[1];
} else {
seg1min = inSeg1Pt2;
seg1minVal = inSeg1Pt2[1];
seg1max = inSeg1Pt1;
seg1maxVal = inSeg1Pt1[1];
}
if (inSeg2Pt1[1] < inSeg2Pt2[1]) {
seg2min = inSeg2Pt1;
seg2minVal = inSeg2Pt1[1];
seg2max = inSeg2Pt2;
seg2maxVal = inSeg2Pt2[1];
} else {
seg2min = inSeg2Pt2;
seg2minVal = inSeg2Pt2[1];
seg2max = inSeg2Pt1;
seg2maxVal = inSeg2Pt1[1];
}
}
if (seg1minVal <= seg2minVal) {
if (seg1maxVal < seg2minVal) return [];
if (seg1maxVal === seg2minVal) {
if (inExcludeAdjacentSegs) return [];
return [seg2min];
}
if (seg1maxVal <= seg2maxVal) return [seg2min, seg1max];
return [seg2min, seg2max];
} else {
if (seg1minVal > seg2maxVal) return [];
if (seg1minVal === seg2maxVal) {
if (inExcludeAdjacentSegs) return [];
return [seg1min];
}
if (seg1maxVal <= seg2maxVal) return [seg1min, seg1max];
return [seg1min, seg2max];
}
}
}
/**
* 从拉伸几何体中删除孔洞
* @param contour 拉伸几何体的顶点数据
* @param holes 空洞的顶点数据
* @returns {Array} 返回没有镂空(孔洞)的拉伸几何体
*/
function removeHoles(contour, holes) {
var shape = contour.concat();
var hole;
function isCutLineInsideAngles(inShapeIdx, inHoleIdx) {
// 检查孔点是否位于形状的附近
var lastShapeIdx = shape.length - 1;
var prevShapeIdx = inShapeIdx - 1;
if (prevShapeIdx < 0) prevShapeIdx = lastShapeIdx;
var nextShapeIdx = inShapeIdx + 1;
if (nextShapeIdx > lastShapeIdx) nextShapeIdx = 0;
var insideAngle = isPointInsideAngle(shape[inShapeIdx], shape[prevShapeIdx], shape[nextShapeIdx], hole[inHoleIdx]);
if (!insideAngle) {
return false;
}
// Check if shape point lies within angle around hole point
var lastHoleIdx = hole.length - 1;
var prevHoleIdx = inHoleIdx - 1;
if (prevHoleIdx < 0) prevHoleIdx = lastHoleIdx;
var nextHoleIdx = inHoleIdx + 1;
if (nextHoleIdx > lastHoleIdx) nextHoleIdx = 0;
insideAngle = isPointInsideAngle(hole[inHoleIdx], hole[prevHoleIdx], hole[nextHoleIdx], shape[inShapeIdx]);
if (!insideAngle) {
// console.log( "Vertex (Hole): " + inHoleIdx + ", Point: " + shape[inShapeIdx][0] + "/" + shape[inShapeIdx][1] );
return false;
}
return true;
}
function intersectsShapeEdge(inShapePt, inHolePt) {
// checks for intersections with shape edges
var sIdx, nextIdx, intersection;
for (sIdx = 0; sIdx < shape.length; sIdx++) {
nextIdx = sIdx + 1;
nextIdx %= shape.length;
intersection = intersectSegments2D(inShapePt, inHolePt, shape[sIdx], shape[nextIdx], true);
if (intersection.length > 0) return true;
}
return false;
}
var indepHoles = [];
function intersectsHoleEdge(inShapePt, inHolePt) {
// checks for intersections with hole edges
var ihIdx, chkHole,
hIdx, nextIdx, intersection;
for (ihIdx = 0; ihIdx < indepHoles.length; ihIdx++) {
chkHole = holes[indepHoles[ihIdx]];
for (hIdx = 0; hIdx < chkHole.length; hIdx++) {
nextIdx = hIdx + 1;
nextIdx %= chkHole.length;
intersection = intersectSegments2D(inShapePt, inHolePt, chkHole[hIdx], chkHole[nextIdx], true);
if (intersection.length > 0) return true;
}
}
return false;
}
var holeIndex, shapeIndex,
shapePt, holePt,
holeIdx, cutKey, failedCuts = [],
tmpShape1, tmpShape2,
tmpHole1, tmpHole2;
for (var h = 0, hl = holes.length; h < hl; h++) {
indepHoles.push(h);
}
var minShapeIndex = 0;
var counter = indepHoles.length * 2;
while (indepHoles.length > 0) {
counter--;
if (counter < 0) {
console.log("Infinite Loop! Holes left:" + indepHoles.length + ", Probably Hole outside Shape!");
break;
}
// search for shape-vertex and hole-vertex,
// which can be connected without intersections
for (shapeIndex = minShapeIndex; shapeIndex < shape.length; shapeIndex++) {
shapePt = shape[shapeIndex];
holeIndex = -1;
// search for hole which can be reached without intersections
for (var h = 0; h < indepHoles.length; h++) {
holeIdx = indepHoles[h];
// prevent multiple checks
cutKey = shapePt[0] + ":" + shapePt[1] + ":" + holeIdx;
if (failedCuts[cutKey] !== undefined) continue;
hole = holes[holeIdx];
for (var h2 = 0; h2 < hole.length; h2++) {
holePt = hole[h2];
if (!isCutLineInsideAngles(shapeIndex, h2)) continue;
if (intersectsShapeEdge(shapePt, holePt)) continue;
if (intersectsHoleEdge(shapePt, holePt)) continue;
holeIndex = h2;
indepHoles.splice(h, 1);
tmpShape1 = shape.slice(0, shapeIndex + 1);
tmpShape2 = shape.slice(shapeIndex);
tmpHole1 = hole.slice(holeIndex);
tmpHole2 = hole.slice(0, holeIndex + 1);
shape = tmpShape1.concat(tmpHole1).concat(tmpHole2).concat(tmpShape2);
minShapeIndex = shapeIndex;
// Debug only, to show the selected cuts
// glob_CutLines.push( [ shapePt, holePt ] );
break;
}
if (holeIndex >= 0) break; // hole-vertex found
failedCuts[cutKey] = true; // remember failure
}
if (holeIndex >= 0) break; // hole-vertex found
}
}
return shape;
/* shape with no holes */
}
function snip(contour, u, v, w, n, verts) {
var p;
var ax, ay, bx, by;
var cx, cy, px, py;
ax = contour[verts[u]][0];
ay = contour[verts[u]][1];
bx = contour[verts[v]][0];
by = contour[verts[v]][1];
cx = contour[verts[w]][0];
cy = contour[verts[w]][1];
if (Number.EPSILON > ( ( ( bx - ax ) * ( cy - ay ) ) - ( ( by - ay ) * ( cx - ax ) ) )) return false;
var aX, aY, bX, bY, cX, cY;
var apx, apy, bpx, bpy, cpx, cpy;
var cCROSSap, bCROSScp, aCROSSbp;
aX = cx - bx;
aY = cy - by;
bX = ax - cx;
bY = ay - cy;
cX = bx - ax;
cY = by - ay;
for (p = 0; p < n; p++) {
px = contour[verts[p]][0];
py = contour[verts[p]][1];
if (( ( px === ax ) && ( py === ay ) ) ||
( ( px === bx ) && ( py === by ) ) ||
( ( px === cx ) && ( py === cy ) )) continue;
apx = px - ax;
apy = py - ay;
bpx = px - bx;
bpy = py - by;
cpx = px - cx;
cpy = py - cy;
// see if p is inside triangle abc
aCROSSbp = aX * bpy - aY * bpx;
cCROSSap = cX * apy - cY * apx;
bCROSScp = bX * cpy - bY * cpx;
if (( aCROSSbp >= -Number.EPSILON ) && ( bCROSScp >= -Number.EPSILON ) && ( cCROSSap >= -Number.EPSILON )) return false;
}
return true;
}
function triangulate(contour, indices) {
var n = contour.length;
if (n < 3) return null;
var result = [],
verts = [],
vertIndices = [];
/* we want a counter-clockwise polygon in verts */
var u, v, w, area = 0.0;
for (var p = n - 1, i = 0; i < n; p = i++) {
area += contour[p][0] * contour[i][1] - contour[i][0] * contour[p][1];
}
if (area * 0.5 > 0.0) {
for (v = 0; v < n; v++) {
verts[v] = v;
}
} else {
for (v = 0; v < n; v++) {
verts[v] = ( n - 1 ) - v;
}
}
var nv = n;
/* remove nv - 2 vertices, creating 1 triangle every time */
var count = 2 * nv;
/* error detection */
for (v = nv - 1; nv > 2;) {
/* if we loop, it is probably a non-simple polygon */
if (( count-- ) <= 0) {
//** Triangulate: ERROR - probable bad polygon!
//throw ( "Warning, unable to triangulate polygon!" );
//return null;
// Sometimes warning is fine, especially polygons are triangulated in reverse.
//可能发生了处理的情况
if (indices) return vertIndices;
return result;
}
/* three consecutive vertices in current polygon, <u,v,w> */
u = v;
if (nv <= u) u = 0;
/* previous */
v = u + 1;
if (nv <= v) v = 0;
/* new v */
w = v + 1;
if (nv <= w) w = 0;
/* next */
if (snip(contour, u, v, w, nv, verts)) {
var a, b, c, s, t;
/* true names of the vertices */
a = verts[u];
b = verts[v];
c = verts[w];
/* output Triangle */
result.push([
contour[a],
contour[b],
contour[c]
]);
vertIndices.push([verts[u], verts[v], verts[w]]);
/* remove v from the remaining polygon */
for (s = v, t = v + 1; t < nv; s++, t++) {
verts[s] = verts[t];
}
nv--;
/* reset error detection counter */
count = 2 * nv;
}
}
if (indices) return vertIndices;
return result;
}
function pointInSegment2DColin(inSegPt1, inSegPt2, inOtherPt) {
// inOtherPt needs to be collinear to the inSegment
if (inSegPt1[0] !== inSegPt2[0]) {
if (inSegPt1[0] < inSegPt2[0]) {
return ( ( inSegPt1[0] <= inOtherPt[0] ) && ( inOtherPt[0] <= inSegPt2[0] ) );
} else {
return ( ( inSegPt2[0] <= inOtherPt[0] ) && ( inOtherPt[0] <= inSegPt1[0] ) );
}
} else {
if (inSegPt1[1] < inSegPt2[1]) {
return ( ( inSegPt1[1] <= inOtherPt[1] ) && ( inOtherPt[1] <= inSegPt2[1] ) );