https://www.cambridgeairphotos.com/js/lib/Google.js

1/*
2 * Google layer using Google Maps API
3 */
4
5/* global google: true */
6
7L.Google = L.Class.extend({
8	includes: L.Mixin.Events,
9
10	options: {
11		minZoom: 0,
12		maxZoom: 18,
13		tileSize: 256,
14		subdomains: 'abc',
15		errorTileUrl: '',
16		attribution: '',
17		opacity: 1,
18		continuousWorld: false,
19		noWrap: false,
20		mapOptions: {
21			backgroundColor: '#dddddd'
22		}
23	},
24
25	// Possible types: SATELLITE, ROADMAP, HYBRID, TERRAIN
26	initialize: function(type, options) {
27		L.Util.setOptions(this, options);
28
29		this._ready = google.maps.Map !== undefined;
30		if (!this._ready) L.Google.asyncWait.push(this);
31
32		this._type = type || 'SATELLITE';
33	},
34
35	onAdd: function(map, insertAtTheBottom) {
36		this._map = map;
37		this._insertAtTheBottom = insertAtTheBottom;
38
39		// create a container div for tiles
40		this._initContainer();
41		this._initMapObject();
42
43		// set up events
44		map.on('viewreset', this._resetCallback, this);
45
46		this._limitedUpdate = L.Util.limitExecByInterval(this._update, 150, this);
47		map.on('move', this._update, this);
48
49		map.on('zoomanim', this._handleZoomAnim, this);
50
51		//20px instead of 1em to avoid a slight overlap with google's attribution
52		map._controlCorners.bottomright.style.marginBottom = '20px';
53
54		this._reset();
55		this._update();
56	},
57
58	onRemove: function(map) {
59		this._map._container.removeChild(this._container);
60		//this._container = null;
61
62		this._map.off('viewreset', this._resetCallback, this);
63
64		this._map.off('move', this._update, this);
65
66		this._map.off('zoomanim', this._handleZoomAnim, this);
67
68		map._controlCorners.bottomright.style.marginBottom = '0em';
69		//this._map.off('moveend', this._update, this);
70	},
71
72	getAttribution: function() {
73		return this.options.attribution;
74	},
75
76	setOpacity: function(opacity) {
77		this.options.opacity = opacity;
78		if (opacity < 1) {
79			L.DomUtil.setOpacity(this._container, opacity);
80		}
81	},
82
83	setElementSize: function(e, size) {
84		e.style.width = size.x + 'px';
85		e.style.height = size.y + 'px';
86	},
87
88	_initContainer: function() {
89		var tilePane = this._map._container,
90			first = tilePane.firstChild;
91
92		if (!this._container) {
93			this._container = L.DomUtil.create('div', 'leaflet-google-layer leaflet-top leaflet-left');
94			this._container.id = '_GMapContainer_' + L.Util.stamp(this);
95			this._container.style.zIndex = 'auto';
96		}
97
98		tilePane.insertBefore(this._container, first);
99
100		this.setOpacity(this.options.opacity);
101		this.setElementSize(this._container, this._map.getSize());
102	},
103
104	_initMapObject: function() {
105		if (!this._ready) return;
106		this._google_center = new google.maps.LatLng(0, 0);
107		var map = new google.maps.Map(this._container, {
108		    center: this._google_center,
109		    zoom: 0,
110		    tilt: 0,
111		    mapTypeId: google.maps.MapTypeId[this._type],
112		    disableDefaultUI: true,
113		    keyboardShortcuts: false,
114		    draggable: false,
115		    disableDoubleClickZoom: true,
116		    scrollwheel: false,
117		    streetViewControl: false,
118		    styles: this.options.mapOptions.styles,
119		    backgroundColor: this.options.mapOptions.backgroundColor
120		});
121
122		var _this = this;
123		this._reposition = google.maps.event.addListenerOnce(map, 'center_changed',
124			function() { _this.onReposition(); });
125		this._google = map;
126
127		google.maps.event.addListenerOnce(map, 'idle',
128			function() { _this._checkZoomLevels(); });
129	},
130
131	_checkZoomLevels: function() {
132		//setting the zoom level on the Google map may result in a different zoom level than the one requested
133		//(it won't go beyond the level for which they have data).
134		// verify and make sure the zoom levels on both Leaflet and Google maps are consistent
135		if (this._google.getZoom() !== this._map.getZoom()) {
136			//zoom levels are out of sync. Set the leaflet zoom level to match the google one
137			this._map.setZoom( this._google.getZoom() );
138		}
139	},
140
141	_resetCallback: function(e) {
142		this._reset(e.hard);
143	},
144
145	_reset: function(clearOldContainer) {
146		this._initContainer();
147	},
148
149	_update: function(e) {
150		if (!this._google) return;
151		this._resize();
152
153		var center = e && e.latlng ? e.latlng : this._map.getCenter();
154		var _center = new google.maps.LatLng(center.lat, center.lng);
155
156		this._google.setCenter(_center);
157		this._google.setZoom(this._map.getZoom());
158
159		this._checkZoomLevels();
160		//this._google.fitBounds(google_bounds);
161	},
162
163	_resize: function() {
164		var size = this._map.getSize();
165		if (this._container.style.width === size.x &&
166		    this._container.style.height === size.y)
167			return;
168		this.setElementSize(this._container, size);
169		this.onReposition();
170	},
171
172
173	_handleZoomAnim: function (e) {
174		var center = e.center;
175		var _center = new google.maps.LatLng(center.lat, center.lng);
176
177		this._google.setCenter(_center);
178		this._google.setZoom(e.zoom);
179	},
180
181
182	onReposition: function() {
183		if (!this._google) return;
184		google.maps.event.trigger(this._google, 'resize');
185	}
186});
187
188L.Google.asyncWait = [];
189L.Google.asyncInitialize = function() {
190	var i;
191	for (i = 0; i < L.Google.asyncWait.length; i++) {
192		var o = L.Google.asyncWait[i];
193		o._ready = true;
194		if (o._container) {
195			o._initMapObject();
196			o._update();
197		}
198	}
199	L.Google.asyncWait = [];
200};