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 | 1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
1×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
134×
70×
64×
15×
134×
134×
1×
1×
1×
1×
1×
112×
112×
112×
1×
1×
263×
1×
114×
1×
4×
4×
4×
4×
4×
4×
4×
1×
78×
1×
269×
1×
10×
10×
10×
1×
1×
103×
1×
1×
78×
78×
78×
78×
78×
78×
1×
18×
18×
18×
17×
17×
75×
75×
14×
14×
61×
18×
1×
11×
5×
4×
3×
9×
9×
9×
9×
9×
9×
1×
8×
1×
7×
9×
9×
9×
9×
9×
9×
9×
9×
9×
9×
9×
29×
29×
29×
29×
29×
29×
9×
9×
9×
7×
7×
3×
7×
9×
9×
9×
9×
9×
9×
9×
9×
9×
1×
2×
2×
2×
2×
2×
2×
2×
2×
2×
2×
2×
2×
1×
160×
1×
1×
13×
1×
114×
114×
114×
114×
1×
29×
1×
9×
1×
10×
10×
1×
134×
134×
1×
147×
147×
147×
147×
147×
147×
147×
147×
147×
10×
10×
10×
10×
137×
137×
137×
137×
137×
137×
137×
6×
131×
137×
137×
133×
5×
1×
4×
128×
137×
137×
137×
147×
1×
135×
135×
135×
135×
135×
| goog.provide('ol.View');
goog.provide('ol.ViewHint');
goog.provide('ol.ViewProperty');
goog.require('goog.asserts');
goog.require('ol');
goog.require('ol.CenterConstraint');
goog.require('ol.Constraints');
goog.require('ol.Object');
goog.require('ol.ResolutionConstraint');
goog.require('ol.RotationConstraint');
goog.require('ol.RotationConstraintType');
goog.require('ol.Size');
goog.require('ol.coordinate');
goog.require('ol.extent');
goog.require('ol.geom.Polygon');
goog.require('ol.geom.SimpleGeometry');
goog.require('ol.proj');
goog.require('ol.proj.METERS_PER_UNIT');
goog.require('ol.proj.Projection');
goog.require('ol.proj.Units');
/**
* @enum {string}
*/
ol.ViewProperty = {
CENTER: 'center',
RESOLUTION: 'resolution',
ROTATION: 'rotation'
};
/**
* @enum {number}
*/
ol.ViewHint = {
ANIMATING: 0,
INTERACTING: 1
};
/**
* @classdesc
* An ol.View object represents a simple 2D view of the map.
*
* This is the object to act upon to change the center, resolution,
* and rotation of the map.
*
* ### The view states
*
* An `ol.View` is determined by three states: `center`, `resolution`,
* and `rotation`. Each state has a corresponding getter and setter, e.g.
* `getCenter` and `setCenter` for the `center` state.
*
* An `ol.View` has a `projection`. The projection determines the
* coordinate system of the center, and its units determine the units of the
* resolution (projection units per pixel). The default projection is
* Spherical Mercator (EPSG:3857).
*
* ### The constraints
*
* `setCenter`, `setResolution` and `setRotation` can be used to change the
* states of the view. Any value can be passed to the setters. And the value
* that is passed to a setter will effectively be the value set in the view,
* and returned by the corresponding getter.
*
* But an `ol.View` object also has a *resolution constraint*, a
* *rotation constraint* and a *center constraint*.
*
* As said above, no constraints are applied when the setters are used to set
* new states for the view. Applying constraints is done explicitly through
* the use of the `constrain*` functions (`constrainResolution` and
* `constrainRotation` and `constrainCenter`).
*
* The main users of the constraints are the interactions and the
* controls. For example, double-clicking on the map changes the view to
* the "next" resolution. And releasing the fingers after pinch-zooming
* snaps to the closest resolution (with an animation).
*
* The *resolution constraint* snaps to specific resolutions. It is
* determined by the following options: `resolutions`, `maxResolution`,
* `maxZoom`, and `zoomFactor`. If `resolutions` is set, the other three
* options are ignored. See documentation for each option for more
* information.
*
* The *rotation constraint* snaps to specific angles. It is determined
* by the following options: `enableRotation` and `constrainRotation`.
* By default the rotation value is snapped to zero when approaching the
* horizontal.
*
* The *center constraint* is determined by the `extent` option. By
* default the center is not constrained at all.
*
* @constructor
* @extends {ol.Object}
* @param {olx.ViewOptions=} opt_options View options.
* @api stable
*/
ol.View = function(opt_options) {
goog.base(this);
var options = opt_options || {};
/**
* @private
* @type {Array.<number>}
*/
this.hints_ = [0, 0];
/**
* @type {Object.<string, *>}
*/
var properties = {};
properties[ol.ViewProperty.CENTER] = options.center !== undefined ?
options.center : null;
/**
* @private
* @const
* @type {ol.proj.Projection}
*/
this.projection_ = ol.proj.createProjection(options.projection, 'EPSG:3857');
var resolutionConstraintInfo = ol.View.createResolutionConstraint_(
options);
/**
* @private
* @type {number}
*/
this.maxResolution_ = resolutionConstraintInfo.maxResolution;
/**
* @private
* @type {number}
*/
this.minResolution_ = resolutionConstraintInfo.minResolution;
/**
* @private
* @type {number}
*/
this.minZoom_ = resolutionConstraintInfo.minZoom;
var centerConstraint = ol.View.createCenterConstraint_(options);
var resolutionConstraint = resolutionConstraintInfo.constraint;
var rotationConstraint = ol.View.createRotationConstraint_(options);
/**
* @private
* @type {ol.Constraints}
*/
this.constraints_ = new ol.Constraints(
centerConstraint, resolutionConstraint, rotationConstraint);
if (options.resolution !== undefined) {
properties[ol.ViewProperty.RESOLUTION] = options.resolution;
} else if (options.zoom !== undefined) {
properties[ol.ViewProperty.RESOLUTION] = this.constrainResolution(
this.maxResolution_, options.zoom - this.minZoom_);
}
properties[ol.ViewProperty.ROTATION] =
options.rotation !== undefined ? options.rotation : 0;
this.setProperties(properties);
};
goog.inherits(ol.View, ol.Object);
/**
* @param {number} rotation Target rotation.
* @param {ol.Coordinate} anchor Rotation anchor.
* @return {ol.Coordinate|undefined} Center for rotation and anchor.
*/
ol.View.prototype.calculateCenterRotate = function(rotation, anchor) {
var center;
var currentCenter = this.getCenter();
if (currentCenter !== undefined) {
center = [currentCenter[0] - anchor[0], currentCenter[1] - anchor[1]];
ol.coordinate.rotate(center, rotation - this.getRotation());
ol.coordinate.add(center, anchor);
}
return center;
};
/**
* @param {number} resolution Target resolution.
* @param {ol.Coordinate} anchor Zoom anchor.
* @return {ol.Coordinate|undefined} Center for resolution and anchor.
*/
ol.View.prototype.calculateCenterZoom = function(resolution, anchor) {
var center;
var currentCenter = this.getCenter();
var currentResolution = this.getResolution();
if (currentCenter !== undefined && currentResolution !== undefined) {
var x = anchor[0] -
resolution * (anchor[0] - currentCenter[0]) / currentResolution;
var y = anchor[1] -
resolution * (anchor[1] - currentCenter[1]) / currentResolution;
center = [x, y];
}
return center;
};
/**
* Get the constrained center of this view.
* @param {ol.Coordinate|undefined} center Center.
* @return {ol.Coordinate|undefined} Constrained center.
* @api
*/
ol.View.prototype.constrainCenter = function(center) {
return this.constraints_.center(center);
};
/**
* Get the constrained resolution of this view.
* @param {number|undefined} resolution Resolution.
* @param {number=} opt_delta Delta. Default is `0`.
* @param {number=} opt_direction Direction. Default is `0`.
* @return {number|undefined} Constrained resolution.
* @api
*/
ol.View.prototype.constrainResolution = function(
resolution, opt_delta, opt_direction) {
var delta = opt_delta || 0;
var direction = opt_direction || 0;
return this.constraints_.resolution(resolution, delta, direction);
};
/**
* Get the constrained rotation of this view.
* @param {number|undefined} rotation Rotation.
* @param {number=} opt_delta Delta. Default is `0`.
* @return {number|undefined} Constrained rotation.
* @api
*/
ol.View.prototype.constrainRotation = function(rotation, opt_delta) {
var delta = opt_delta || 0;
return this.constraints_.rotation(rotation, delta);
};
/**
* Get the view center.
* @return {ol.Coordinate|undefined} The center of the view.
* @observable
* @api stable
*/
ol.View.prototype.getCenter = function() {
return /** @type {ol.Coordinate|undefined} */ (
this.get(ol.ViewProperty.CENTER));
};
/**
* @return {Array.<number>} Hint.
*/
ol.View.prototype.getHints = function() {
return this.hints_.slice();
};
/**
* Calculate the extent for the current view state and the passed size.
* The size is the pixel dimensions of the box into which the calculated extent
* should fit. In most cases you want to get the extent of the entire map,
* that is `map.getSize()`.
* @param {ol.Size} size Box pixel size.
* @return {ol.Extent} Extent.
* @api stable
*/
ol.View.prototype.calculateExtent = function(size) {
var center = this.getCenter();
goog.asserts.assert(center, 'The view center is not defined');
var resolution = this.getResolution();
goog.asserts.assert(resolution !== undefined,
'The view resolution is not defined');
var rotation = this.getRotation();
goog.asserts.assert(rotation !== undefined,
'The view rotation is not defined');
return ol.extent.getForViewAndSize(center, resolution, rotation, size);
};
/**
* Get the view projection.
* @return {ol.proj.Projection} The projection of the view.
* @api stable
*/
ol.View.prototype.getProjection = function() {
return this.projection_;
};
/**
* Get the view resolution.
* @return {number|undefined} The resolution of the view.
* @observable
* @api stable
*/
ol.View.prototype.getResolution = function() {
return /** @type {number|undefined} */ (
this.get(ol.ViewProperty.RESOLUTION));
};
/**
* Get the resolution for a provided extent (in map units) and size (in pixels).
* @param {ol.Extent} extent Extent.
* @param {ol.Size} size Box pixel size.
* @return {number} The resolution at which the provided extent will render at
* the given size.
*/
ol.View.prototype.getResolutionForExtent = function(extent, size) {
var xResolution = ol.extent.getWidth(extent) / size[0];
var yResolution = ol.extent.getHeight(extent) / size[1];
return Math.max(xResolution, yResolution);
};
/**
* Return a function that returns a value between 0 and 1 for a
* resolution. Exponential scaling is assumed.
* @param {number=} opt_power Power.
* @return {function(number): number} Resolution for value function.
*/
ol.View.prototype.getResolutionForValueFunction = function(opt_power) {
var power = opt_power || 2;
var maxResolution = this.maxResolution_;
var minResolution = this.minResolution_;
var max = Math.log(maxResolution / minResolution) / Math.log(power);
return (
/**
* @param {number} value Value.
* @return {number} Resolution.
*/
function(value) {
var resolution = maxResolution / Math.pow(power, value * max);
goog.asserts.assert(resolution >= minResolution &&
resolution <= maxResolution,
'calculated resolution outside allowed bounds (%s <= %s <= %s)',
minResolution, resolution, maxResolution);
return resolution;
});
};
/**
* Get the view rotation.
* @return {number} The rotation of the view in radians.
* @observable
* @api stable
*/
ol.View.prototype.getRotation = function() {
return /** @type {number} */ (this.get(ol.ViewProperty.ROTATION));
};
/**
* Return a function that returns a resolution for a value between
* 0 and 1. Exponential scaling is assumed.
* @param {number=} opt_power Power.
* @return {function(number): number} Value for resolution function.
*/
ol.View.prototype.getValueForResolutionFunction = function(opt_power) {
var power = opt_power || 2;
var maxResolution = this.maxResolution_;
var minResolution = this.minResolution_;
var max = Math.log(maxResolution / minResolution) / Math.log(power);
return (
/**
* @param {number} resolution Resolution.
* @return {number} Value.
*/
function(resolution) {
var value =
(Math.log(maxResolution / resolution) / Math.log(power)) / max;
goog.asserts.assert(value >= 0 && value <= 1,
'calculated value (%s) ouside allowed range (0-1)', value);
return value;
});
};
/**
* @return {olx.ViewState} View state.
*/
ol.View.prototype.getState = function() {
goog.asserts.assert(this.isDef(),
'the view was not defined (had no center and/or resolution)');
var center = /** @type {ol.Coordinate} */ (this.getCenter());
var projection = this.getProjection();
var resolution = /** @type {number} */ (this.getResolution());
var rotation = this.getRotation();
return /** @type {olx.ViewState} */ ({
// Snap center to closest pixel
center: [
Math.round(center[0] / resolution) * resolution,
Math.round(center[1] / resolution) * resolution
],
projection: projection !== undefined ? projection : null,
resolution: resolution,
rotation: rotation
});
};
/**
* Get the current zoom level. Return undefined if the current
* resolution is undefined or not a "constrained resolution".
* @return {number|undefined} Zoom.
* @api stable
*/
ol.View.prototype.getZoom = function() {
var offset;
var resolution = this.getResolution();
if (resolution !== undefined) {
var res, z = 0;
do {
res = this.constrainResolution(this.maxResolution_, z);
if (res == resolution) {
offset = z;
break;
}
++z;
} while (res > this.minResolution_);
}
return offset !== undefined ? this.minZoom_ + offset : offset;
};
/**
* Fit the given geometry or extent based on the given map size and border.
* The size is pixel dimensions of the box to fit the extent into.
* In most cases you will want to use the map size, that is `map.getSize()`.
* Takes care of the map angle.
* @param {ol.geom.SimpleGeometry|ol.Extent} geometry Geometry.
* @param {ol.Size} size Box pixel size.
* @param {olx.view.FitOptions=} opt_options Options.
* @api
*/
ol.View.prototype.fit = function(geometry, size, opt_options) {
if (!(geometry instanceof ol.geom.SimpleGeometry)) {
goog.asserts.assert(goog.isArray(geometry),
'invalid extent or geometry');
goog.asserts.assert(!ol.extent.isEmpty(geometry),
'cannot fit empty extent');
geometry = ol.geom.Polygon.fromExtent(geometry);
}
var options = opt_options || {};
var padding = options.padding !== undefined ? options.padding : [0, 0, 0, 0];
var constrainResolution = options.constrainResolution !== undefined ?
options.constrainResolution : true;
var nearest = options.nearest !== undefined ? options.nearest : false;
var minResolution;
if (options.minResolution !== undefined) {
minResolution = options.minResolution;
} else if (options.maxZoom !== undefined) {
minResolution = this.constrainResolution(
this.maxResolution_, options.maxZoom - this.minZoom_, 0);
} else {
minResolution = 0;
}
var coords = geometry.getFlatCoordinates();
// calculate rotated extent
var rotation = this.getRotation();
goog.asserts.assert(rotation !== undefined, 'rotation was not defined');
var cosAngle = Math.cos(-rotation);
var sinAngle = Math.sin(-rotation);
var minRotX = +Infinity;
var minRotY = +Infinity;
var maxRotX = -Infinity;
var maxRotY = -Infinity;
var stride = geometry.getStride();
for (var i = 0, ii = coords.length; i < ii; i += stride) {
var rotX = coords[i] * cosAngle - coords[i + 1] * sinAngle;
var rotY = coords[i] * sinAngle + coords[i + 1] * cosAngle;
minRotX = Math.min(minRotX, rotX);
minRotY = Math.min(minRotY, rotY);
maxRotX = Math.max(maxRotX, rotX);
maxRotY = Math.max(maxRotY, rotY);
}
// calculate resolution
var resolution = this.getResolutionForExtent(
[minRotX, minRotY, maxRotX, maxRotY],
[size[0] - padding[1] - padding[3], size[1] - padding[0] - padding[2]]);
resolution = isNaN(resolution) ? minResolution :
Math.max(resolution, minResolution);
if (constrainResolution) {
var constrainedResolution = this.constrainResolution(resolution, 0, 0);
if (!nearest && constrainedResolution < resolution) {
constrainedResolution = this.constrainResolution(
constrainedResolution, -1, 0);
}
resolution = constrainedResolution;
}
this.setResolution(resolution);
// calculate center
sinAngle = -sinAngle; // go back to original rotation
var centerRotX = (minRotX + maxRotX) / 2;
var centerRotY = (minRotY + maxRotY) / 2;
centerRotX += (padding[1] - padding[3]) / 2 * resolution;
centerRotY += (padding[0] - padding[2]) / 2 * resolution;
var centerX = centerRotX * cosAngle - centerRotY * sinAngle;
var centerY = centerRotY * cosAngle + centerRotX * sinAngle;
this.setCenter([centerX, centerY]);
};
/**
* Center on coordinate and view position.
* @param {ol.Coordinate} coordinate Coordinate.
* @param {ol.Size} size Box pixel size.
* @param {ol.Pixel} position Position on the view to center on.
* @api
*/
ol.View.prototype.centerOn = function(coordinate, size, position) {
// calculate rotated position
var rotation = this.getRotation();
var cosAngle = Math.cos(-rotation);
var sinAngle = Math.sin(-rotation);
var rotX = coordinate[0] * cosAngle - coordinate[1] * sinAngle;
var rotY = coordinate[1] * cosAngle + coordinate[0] * sinAngle;
var resolution = this.getResolution();
rotX += (size[0] / 2 - position[0]) * resolution;
rotY += (position[1] - size[1] / 2) * resolution;
// go back to original angle
sinAngle = -sinAngle; // go back to original rotation
var centerX = rotX * cosAngle - rotY * sinAngle;
var centerY = rotY * cosAngle + rotX * sinAngle;
this.setCenter([centerX, centerY]);
};
/**
* @return {boolean} Is defined.
*/
ol.View.prototype.isDef = function() {
return !!this.getCenter() && this.getResolution() !== undefined;
};
/**
* Rotate the view around a given coordinate.
* @param {number} rotation New rotation value for the view.
* @param {ol.Coordinate=} opt_anchor The rotation center.
* @api stable
*/
ol.View.prototype.rotate = function(rotation, opt_anchor) {
if (opt_anchor !== undefined) {
var center = this.calculateCenterRotate(rotation, opt_anchor);
this.setCenter(center);
}
this.setRotation(rotation);
};
/**
* Set the center of the current view.
* @param {ol.Coordinate|undefined} center The center of the view.
* @observable
* @api stable
*/
ol.View.prototype.setCenter = function(center) {
this.set(ol.ViewProperty.CENTER, center);
};
/**
* @param {ol.ViewHint} hint Hint.
* @param {number} delta Delta.
* @return {number} New value.
*/
ol.View.prototype.setHint = function(hint, delta) {
goog.asserts.assert(0 <= hint && hint < this.hints_.length,
'illegal hint (%s), must be between 0 and %s', hint, this.hints_.length);
this.hints_[hint] += delta;
goog.asserts.assert(this.hints_[hint] >= 0,
'Hint at %s must be positive, was %s', hint, this.hints_[hint]);
return this.hints_[hint];
};
/**
* Set the resolution for this view.
* @param {number|undefined} resolution The resolution of the view.
* @observable
* @api stable
*/
ol.View.prototype.setResolution = function(resolution) {
this.set(ol.ViewProperty.RESOLUTION, resolution);
};
/**
* Set the rotation for this view.
* @param {number} rotation The rotation of the view in radians.
* @observable
* @api stable
*/
ol.View.prototype.setRotation = function(rotation) {
this.set(ol.ViewProperty.ROTATION, rotation);
};
/**
* Zoom to a specific zoom level.
* @param {number} zoom Zoom level.
* @api stable
*/
ol.View.prototype.setZoom = function(zoom) {
var resolution = this.constrainResolution(
this.maxResolution_, zoom - this.minZoom_, 0);
this.setResolution(resolution);
};
/**
* @param {olx.ViewOptions} options View options.
* @private
* @return {ol.CenterConstraintType}
*/
ol.View.createCenterConstraint_ = function(options) {
Iif (options.extent !== undefined) {
return ol.CenterConstraint.createExtent(options.extent);
} else {
return ol.CenterConstraint.none;
}
};
/**
* @private
* @param {olx.ViewOptions} options View options.
* @return {{constraint: ol.ResolutionConstraintType, maxResolution: number,
* minResolution: number}}
*/
ol.View.createResolutionConstraint_ = function(options) {
var resolutionConstraint;
var maxResolution;
var minResolution;
// TODO: move these to be ol constants
// see https://github.com/openlayers/ol3/issues/2076
var defaultMaxZoom = 28;
var defaultZoomFactor = 2;
var minZoom = options.minZoom !== undefined ?
options.minZoom : ol.DEFAULT_MIN_ZOOM;
var maxZoom = options.maxZoom !== undefined ?
options.maxZoom : defaultMaxZoom;
var zoomFactor = options.zoomFactor !== undefined ?
options.zoomFactor : defaultZoomFactor;
if (options.resolutions !== undefined) {
var resolutions = options.resolutions;
maxResolution = resolutions[0];
minResolution = resolutions[resolutions.length - 1];
resolutionConstraint = ol.ResolutionConstraint.createSnapToResolutions(
resolutions);
} else {
// calculate the default min and max resolution
var projection = ol.proj.createProjection(options.projection, 'EPSG:3857');
var extent = projection.getExtent();
var size = !extent ?
// use an extent that can fit the whole world if need be
360 * ol.proj.METERS_PER_UNIT[ol.proj.Units.DEGREES] /
ol.proj.METERS_PER_UNIT[projection.getUnits()] :
Math.max(ol.extent.getWidth(extent), ol.extent.getHeight(extent));
var defaultMaxResolution = size / ol.DEFAULT_TILE_SIZE / Math.pow(
defaultZoomFactor, ol.DEFAULT_MIN_ZOOM);
var defaultMinResolution = defaultMaxResolution / Math.pow(
defaultZoomFactor, defaultMaxZoom - ol.DEFAULT_MIN_ZOOM);
// user provided maxResolution takes precedence
maxResolution = options.maxResolution;
if (maxResolution !== undefined) {
minZoom = 0;
} else {
maxResolution = defaultMaxResolution / Math.pow(zoomFactor, minZoom);
}
// user provided minResolution takes precedence
minResolution = options.minResolution;
if (minResolution === undefined) {
if (options.maxZoom !== undefined) {
if (options.maxResolution !== undefined) {
minResolution = maxResolution / Math.pow(zoomFactor, maxZoom);
} else {
minResolution = defaultMaxResolution / Math.pow(zoomFactor, maxZoom);
}
} else {
minResolution = defaultMinResolution;
}
}
// given discrete zoom levels, minResolution may be different than provided
maxZoom = minZoom + Math.floor(
Math.log(maxResolution / minResolution) / Math.log(zoomFactor));
minResolution = maxResolution / Math.pow(zoomFactor, maxZoom - minZoom);
resolutionConstraint = ol.ResolutionConstraint.createSnapToPower(
zoomFactor, maxResolution, maxZoom - minZoom);
}
return {constraint: resolutionConstraint, maxResolution: maxResolution,
minResolution: minResolution, minZoom: minZoom};
};
/**
* @private
* @param {olx.ViewOptions} options View options.
* @return {ol.RotationConstraintType} Rotation constraint.
*/
ol.View.createRotationConstraint_ = function(options) {
var enableRotation = options.enableRotation !== undefined ?
options.enableRotation : true;
Eif (enableRotation) {
var constrainRotation = options.constrainRotation;
Eif (constrainRotation === undefined || constrainRotation === true) {
return ol.RotationConstraint.createSnapToZero();
} else if (constrainRotation === false) {
return ol.RotationConstraint.none;
} else if (goog.isNumber(constrainRotation)) {
return ol.RotationConstraint.createSnapToN(constrainRotation);
} else {
goog.asserts.fail(
'illegal option for constrainRotation (%s)', constrainRotation);
return ol.RotationConstraint.none;
}
} else {
return ol.RotationConstraint.disable;
}
};
|