abe2a52c31
go ahead and commit this (relatively lighttweight) patch to the code so that the projection library base API is there, even though for the most part, it's not usable yet. This changes map.projection from being a string to being a class, with a projCode on it. (Closes #1035) git-svn-id: http://svn.openlayers.org/trunk/openlayers@5401 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
933 lines
30 KiB
JavaScript
933 lines
30 KiB
JavaScript
/* Copyright (c) 2006-2007 MetaCarta, Inc., published under the Clear BSD
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* license. See http://svn.openlayers.org/trunk/openlayers/license.txt for the
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* full text of the license. */
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/**
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* @requires OpenLayers/Map.js
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*
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* Class: OpenLayers.Layer
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*/
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OpenLayers.Layer = OpenLayers.Class({
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/**
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* APIProperty: id
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* {String}
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*/
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id: null,
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/**
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* APIProperty: name
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* {String}
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*/
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name: null,
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/**
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* APIProperty: div
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* {DOMElement}
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*/
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div: null,
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/**
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* Constant: EVENT_TYPES
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* {Array(String)} Supported application event types
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*/
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EVENT_TYPES: ["loadstart", "loadend", "loadcancel", "visibilitychanged"],
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/**
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* APIProperty: events
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* {<OpenLayers.Events>}
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*/
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events: null,
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/**
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* APIProperty: map
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* {<OpenLayers.Map>} This variable is set when the layer is added to
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* the map, via the accessor function setMap().
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*/
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map: null,
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/**
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* APIProperty: isBaseLayer
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* {Boolean} Whether or not the layer is a base layer. This should be set
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* individually by all subclasses. Default is false
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*/
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isBaseLayer: false,
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/**
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* Property: alpha
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* {Boolean} The layer's images have an alpha channel. Default is false.
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*/
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alpha: false,
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/**
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* APIProperty: displayInLayerSwitcher
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* {Boolean} Display the layer's name in the layer switcher. Default is
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* true.
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*/
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displayInLayerSwitcher: true,
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/**
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* APIProperty: visibility
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* {Boolean} The layer should be displayed in the map. Default is true.
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*/
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visibility: true,
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/**
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* APIProperty: attribution
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* {String} Attribution string, displayed when an
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* <OpenLayers.Control.Attribution> has been added to the map.
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*/
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attribution: null,
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/**
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* Property: inRange
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* {Boolean} The current map resolution is within the layer's min/max
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* range. This is set in <OpenLayers.Map.setCenter> whenever the zoom
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* changes.
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*/
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inRange: false,
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/**
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* Propery: imageSize
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* {<OpenLayers.Size>} For layers with a gutter, the image is larger than
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* the tile by twice the gutter in each dimension.
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*/
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imageSize: null,
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/**
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* Property: imageOffset
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* {<OpenLayers.Pixel>} For layers with a gutter, the image offset
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* represents displacement due to the gutter.
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*/
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imageOffset: null,
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// OPTIONS
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/**
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* Property: options
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* {Object} An optional object whose properties will be set on the layer.
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* Any of the layer properties can be set as a property of the options
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* object and sent to the constructor when the layer is created.
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*/
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options: null,
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/**
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* APIProperty: gutter
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* {Integer} Determines the width (in pixels) of the gutter around image
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* tiles to ignore. By setting this property to a non-zero value,
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* images will be requested that are wider and taller than the tile
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* size by a value of 2 x gutter. This allows artifacts of rendering
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* at tile edges to be ignored. Set a gutter value that is equal to
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* half the size of the widest symbol that needs to be displayed.
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* Defaults to zero. Non-tiled layers always have zero gutter.
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*/
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gutter: 0,
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/**
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* APIProperty: projection
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* {<OpenLayers.Projection>} or {<String>} Set in the layer options to
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* override the default projection string this layer - also set maxExtent,
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* maxResolution, and units if appropriate. Can be either a string or
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* an <OpenLayers.Projection> object when created -- will be converted
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* to an object when setMap is called if a string is passed.
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*/
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projection: null,
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/**
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* APIProperty: units
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* {String} The layer map units. Defaults to 'degrees'. Possible values
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* are 'degrees' (or 'dd'), 'm', 'ft', 'km', 'mi', 'inches'.
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*/
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units: null,
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/**
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* APIProperty: scales
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* {Array} An array of map scales in descending order. The values in the
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* array correspond to the map scale denominator. Note that these
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* values only make sense if the display (monitor) resolution of the
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* client is correctly guessed by whomever is configuring the
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* application. In addition, the units property must also be set.
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* Use <resolutions> instead wherever possible.
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*/
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scales: null,
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/**
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* APIProperty: resolutions
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* {Array} A list of map resolutions (map units per pixel) in descending
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* order. If this is not set in the layer constructor, it will be set
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* based on other resolution related properties (maxExtent,
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* maxResolution, maxScale, etc.).
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*/
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resolutions: null,
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/**
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* APIProperty: maxExtent
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* {<OpenLayers.Bounds>} The center of these bounds will not stray outside
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* of the viewport extent during panning. In addition, if
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* <displayOutsideMaxExtent> is set to false, data will not be
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* requested that falls completely outside of these bounds.
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*/
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maxExtent: null,
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/**
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* APIProperty: minExtent
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* {<OpenLayers.Bounds>}
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*/
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minExtent: null,
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/**
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* APIProperty: maxResolution
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* {Float} Default max is 360 deg / 256 px, which corresponds to
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* zoom level 0 on gmaps. Specify a different value in the layer
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* options if you are not using a geographic projection and
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* displaying the whole world.
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*/
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maxResolution: null,
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/**
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* APIProperty: minResolution
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* {Float}
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*/
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minResolution: null,
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/**
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* APIProperty: numZoomLevels
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* {Integer}
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*/
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numZoomLevels: null,
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/**
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* APIProperty: minScale
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* {Float}
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*/
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minScale: null,
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/**
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* APIProperty: maxScale
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* {Float}
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*/
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maxScale: null,
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/**
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* APIProperty: displayOutsideMaxExtent
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* {Boolean} Request map tiles that are completely outside of the max
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* extent for this layer. Defaults to false.
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*/
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displayOutsideMaxExtent: false,
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/**
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* APIProperty: wrapDateLine
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* {Boolean} #487 for more info.
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*/
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wrapDateLine: false,
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/**
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* Constructor: OpenLayers.Layer
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*
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* Parameters:
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* name - {String} The layer name
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* options - {Object} Hashtable of extra options to tag onto the layer
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*/
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initialize: function(name, options) {
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this.addOptions(options);
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this.name = name;
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if (this.id == null) {
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this.id = OpenLayers.Util.createUniqueID(this.CLASS_NAME + "_");
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this.div = OpenLayers.Util.createDiv(this.id);
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this.div.style.width = "100%";
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this.div.style.height = "100%";
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this.events = new OpenLayers.Events(this, this.div,
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this.EVENT_TYPES);
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}
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if (this.wrapDateLine) {
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this.displayOutsideMaxExtent = true;
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}
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},
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/**
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* Method: destroy
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* Destroy is a destructor: this is to alleviate cyclic references which
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* the Javascript garbage cleaner can not take care of on its own.
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*
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* Parameters:
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* setNewBaseLayer - {Boolean} Set a new base layer when this layer has
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* been destroyed. Default is true.
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*/
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destroy: function(setNewBaseLayer) {
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if (setNewBaseLayer == null) {
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setNewBaseLayer = true;
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}
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if (this.map != null) {
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this.map.removeLayer(this, setNewBaseLayer);
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}
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this.projection = null;
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this.map = null;
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this.name = null;
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this.div = null;
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this.options = null;
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if (this.events) {
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this.events.destroy();
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}
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this.events = null;
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},
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/**
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* Method: clone
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*
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* Parameters:
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* obj - {<OpenLayers.Layer>} The layer to be cloned
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*
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* Returns:
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* {<OpenLayers.Layer>} An exact clone of this <OpenLayers.Layer>
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*/
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clone: function (obj) {
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if (obj == null) {
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obj = new OpenLayers.Layer(this.name, this.options);
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}
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// catch any randomly tagged-on properties
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OpenLayers.Util.applyDefaults(obj, this);
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// a cloned layer should never have its map property set
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// because it has not been added to a map yet.
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obj.map = null;
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return obj;
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},
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/**
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* APIMethod: setName
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* Sets the new layer name for this layer. Can trigger a changelayer event
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* on the map.
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*
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* Parameters:
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* newName - {String} The new name.
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*/
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setName: function(newName) {
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if (newName != this.name) {
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this.name = newName;
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if (this.map != null) {
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this.map.events.triggerEvent("changelayer");
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}
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}
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},
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/**
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* APIMethod: addOptions
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*
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* Parameters:
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* newOptions - {Object}
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*/
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addOptions: function (newOptions) {
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if (this.options == null) {
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this.options = {};
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}
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// update our copy for clone
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OpenLayers.Util.extend(this.options, newOptions);
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// add new options to this
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OpenLayers.Util.extend(this, newOptions);
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},
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/**
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* APIMethod: onMapResize
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* This function can be implemented by subclasses
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*/
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onMapResize: function() {
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//this function can be implemented by subclasses
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},
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/**
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* APIMethod: redraw
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* Redraws the layer. Returns true if the layer was redrawn, false if not.
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*
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* Returns:
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* {Boolean} The layer was redrawn.
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*/
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redraw: function() {
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var redrawn = false;
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if (this.map) {
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// min/max Range may have changed
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this.inRange = this.calculateInRange();
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// map's center might not yet be set
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var extent = this.getExtent();
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if (extent && this.inRange && this.visibility) {
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this.moveTo(extent, true, false);
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redrawn = true;
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}
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}
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return redrawn;
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},
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/**
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* Method: moveTo
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*
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* Parameters:
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* bound - {<OpenLayers.Bounds>}
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* zoomChanged - {Boolean} Tells when zoom has changed, as layers have to
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* do some init work in that case.
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* dragging - {Boolean}
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*/
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moveTo:function(bounds, zoomChanged, dragging) {
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var display = this.visibility;
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if (!this.isBaseLayer) {
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display = display && this.inRange;
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}
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this.display(display);
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},
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/**
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* Method: setMap
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* Set the map property for the layer. This is done through an accessor
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* so that subclasses can override this and take special action once
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* they have their map variable set.
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*
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* Here we take care to bring over any of the necessary default
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* properties from the map.
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*
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* Parameters:
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* map - {<OpenLayers.Map>}
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*/
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setMap: function(map) {
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if (this.map == null) {
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this.map = map;
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// grab some essential layer data from the map if it hasn't already
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// been set
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this.maxExtent = this.maxExtent || this.map.maxExtent;
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this.projection = this.projection || this.map.projection;
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if (this.projection && typeof this.projection == "string") {
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this.projection = new OpenLayers.Projection(this.projection);
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}
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// Check the projection to see if we can get units -- if not, refer
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// to properties.
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this.units = this.projection.getUnits() ||
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this.units || this.map.units;
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this.initResolutions();
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if (!this.isBaseLayer) {
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this.inRange = this.calculateInRange();
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var show = ((this.visibility) && (this.inRange));
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this.div.style.display = show ? "" : "none";
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}
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// deal with gutters
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this.setTileSize();
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}
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},
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/**
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* APIMethod: removeMap
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* Just as setMap() allows each layer the possibility to take a
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* personalized action on being added to the map, removeMap() allows
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* each layer to take a personalized action on being removed from it.
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* For now, this will be mostly unused, except for the EventPane layer,
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* which needs this hook so that it can remove the special invisible
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* pane.
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*
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* Parameters:
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* map - {<OpenLayers.Map>}
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*/
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removeMap: function(map) {
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//to be overridden by subclasses
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},
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/**
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* APIMethod: getImageSize
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*
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* Returns:
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* {<OpenLayers.Size>} The size that the image should be, taking into
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* account gutters.
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*/
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getImageSize: function() {
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return (this.imageSize || this.tileSize);
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},
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/**
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* APIMethod: setTileSize
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* Set the tile size based on the map size. This also sets layer.imageSize
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* and layer.imageOffset for use by Tile.Image.
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*
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* Parameters:
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* size - {<OpenLayers.Size>}
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*/
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setTileSize: function(size) {
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var tileSize = (size) ? size :
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((this.tileSize) ? this.tileSize :
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this.map.getTileSize());
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this.tileSize = tileSize;
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if(this.gutter) {
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// layers with gutters need non-null tile sizes
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//if(tileSize == null) {
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// OpenLayers.console.error("Error in layer.setMap() for " +
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// this.name + ": layers with " +
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// "gutters need non-null tile sizes");
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//}
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this.imageOffset = new OpenLayers.Pixel(-this.gutter,
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-this.gutter);
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this.imageSize = new OpenLayers.Size(tileSize.w + (2*this.gutter),
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tileSize.h + (2*this.gutter));
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}
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},
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/**
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* APIMethod: getVisibility
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*
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* Returns:
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* {Boolean} The layer should be displayed (if in range).
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*/
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getVisibility: function() {
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return this.visibility;
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},
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/**
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* APIMethod: setVisibility
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* Set the visibility flag for the layer and hide/show & redraw
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* accordingly. Fire event unless otherwise specified
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*
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|
* Note that visibility is no longer simply whether or not the layer's
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* style.display is set to "block". Now we store a 'visibility' state
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* property on the layer class, this allows us to remember whether or
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* not we *desire* for a layer to be visible. In the case where the
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* map's resolution is out of the layer's range, this desire may be
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* subverted.
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*
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* Parameters:
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* visible - {Boolean} Whether or not to display the layer (if in range)
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*/
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setVisibility: function(visibility) {
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if (visibility != this.visibility) {
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this.visibility = visibility;
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this.display(visibility);
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this.redraw();
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if (this.map != null) {
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this.map.events.triggerEvent("changelayer");
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}
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this.events.triggerEvent("visibilitychanged");
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}
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},
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|
|
/**
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|
* APIMethod: display
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|
* Hide or show the Layer
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|
*
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|
* Parameters:
|
|
* display - {Boolean}
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*/
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display: function(display) {
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if (display != (this.div.style.display != "none")) {
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this.div.style.display = (display) ? "block" : "none";
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}
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},
|
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|
|
/**
|
|
* Method: calculateInRange
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|
*
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|
* Returns:
|
|
* {Boolean} The layer is displayable at the current map's current
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* resolution.
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*/
|
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calculateInRange: function() {
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var inRange = false;
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|
if (this.map) {
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var resolution = this.map.getResolution();
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inRange = ( (resolution >= this.minResolution) &&
|
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(resolution <= this.maxResolution) );
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}
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return inRange;
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},
|
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|
|
/**
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|
* APIMethod: setIsBaseLayer
|
|
*
|
|
* Parameters:
|
|
* isBaseLayer - {Boolean}
|
|
*/
|
|
setIsBaseLayer: function(isBaseLayer) {
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|
if (isBaseLayer != this.isBaseLayer) {
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|
this.isBaseLayer = isBaseLayer;
|
|
if (this.map != null) {
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|
this.map.events.triggerEvent("changelayer");
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|
}
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|
}
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},
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|
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/********************************************************/
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/* */
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|
/* Baselayer Functions */
|
|
/* */
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|
/********************************************************/
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/**
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* Method: initResolutions
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* This method's responsibility is to set up the 'resolutions' array
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* for the layer -- this array is what the layer will use to interface
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* between the zoom levels of the map and the resolution display
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* of the layer.
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*
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* The user has several options that determine how the array is set up.
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*
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* For a detailed explanation, see the following wiki from the
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* openlayers.org homepage:
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* http://trac.openlayers.org/wiki/SettingZoomLevels
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*/
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initResolutions: function() {
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// These are the relevant options which are used for calculating
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// resolutions information.
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//
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var props = new Array(
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'projection', 'units',
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'scales', 'resolutions',
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'maxScale', 'minScale',
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'maxResolution', 'minResolution',
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'minExtent', 'maxExtent',
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'numZoomLevels', 'maxZoomLevel'
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);
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// First we create a new object where we will store all of the
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// resolution-related properties that we find in either the layer's
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// 'options' array or from the map.
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//
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var confProps = {};
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for(var i=0; i < props.length; i++) {
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var property = props[i];
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confProps[property] = this.options[property] || this.map[property];
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}
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// If numZoomLevels hasn't been set and the maxZoomLevel *has*,
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// then use maxZoomLevel to calculate numZoomLevels
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//
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if ( (!confProps.numZoomLevels) && (confProps.maxZoomLevel) ) {
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confProps.numZoomLevels = confProps.maxZoomLevel + 1;
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}
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// First off, we take whatever hodge-podge of values we have and
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// calculate/distill them down into a resolutions[] array
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//
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if ((confProps.scales != null) || (confProps.resolutions != null)) {
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//preset levels
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if (confProps.scales != null) {
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confProps.resolutions = [];
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for(var i = 0; i < confProps.scales.length; i++) {
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var scale = confProps.scales[i];
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confProps.resolutions[i] =
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OpenLayers.Util.getResolutionFromScale(scale,
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confProps.units);
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}
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}
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confProps.numZoomLevels = confProps.resolutions.length;
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} else {
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//maxResolution and numZoomLevels based calculation
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confProps.resolutions = [];
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// determine maxResolution
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if (confProps.minScale) {
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confProps.maxResolution =
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OpenLayers.Util.getResolutionFromScale(confProps.minScale,
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confProps.units);
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} else if (confProps.maxResolution == "auto") {
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var viewSize = this.map.getSize();
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var wRes = confProps.maxExtent.getWidth() / viewSize.w;
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var hRes = confProps.maxExtent.getHeight()/ viewSize.h;
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confProps.maxResolution = Math.max(wRes, hRes);
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}
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// determine minResolution
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if (confProps.maxScale != null) {
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confProps.minResolution =
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OpenLayers.Util.getResolutionFromScale(confProps.maxScale,
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confProps.units);
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} else if ( (confProps.minResolution == "auto") &&
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(confProps.minExtent != null) ) {
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var viewSize = this.map.getSize();
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var wRes = confProps.minExtent.getWidth() / viewSize.w;
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var hRes = confProps.minExtent.getHeight()/ viewSize.h;
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confProps.minResolution = Math.max(wRes, hRes);
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}
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// determine numZoomLevels
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if (confProps.minResolution != null) {
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var ratio = confProps.maxResolution / confProps.minResolution;
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confProps.numZoomLevels =
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Math.floor(Math.log(ratio) / Math.log(2)) + 1;
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}
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// now we have numZoomLevels and maxResolution,
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// we can populate the resolutions array
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for (var i=0; i < confProps.numZoomLevels; i++) {
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var res = confProps.maxResolution / Math.pow(2, i);
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confProps.resolutions.push(res);
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}
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}
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//sort resolutions array ascendingly
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//
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confProps.resolutions.sort( function(a, b) { return(b-a); } );
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// now set our newly calculated values back to the layer
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// Note: We specifically do *not* set them to layer.options, which we
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// will preserve as it was when we added this layer to the map.
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// this way cloned layers reset themselves to new map div
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// dimensions)
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//
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this.resolutions = confProps.resolutions;
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this.maxResolution = confProps.resolutions[0];
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var lastIndex = confProps.resolutions.length - 1;
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this.minResolution = confProps.resolutions[lastIndex];
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this.scales = [];
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for(var i = 0; i < confProps.resolutions.length; i++) {
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this.scales[i] =
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OpenLayers.Util.getScaleFromResolution(confProps.resolutions[i],
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confProps.units);
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}
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this.minScale = this.scales[0];
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this.maxScale = this.scales[this.scales.length - 1];
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this.numZoomLevels = confProps.numZoomLevels;
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},
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/**
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* APIMethod: getResolution
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*
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* Returns:
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* {Float} The currently selected resolution of the map, taken from the
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* resolutions array, indexed by current zoom level.
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*/
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getResolution: function() {
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var zoom = this.map.getZoom();
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return this.resolutions[zoom];
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},
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/**
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* APIMethod: getExtent
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*
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* Returns:
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* {<OpenLayers.Bounds>} A Bounds object which represents the lon/lat
|
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* bounds of the current viewPort.
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*/
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getExtent: function() {
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// just use stock map calculateBounds function -- passing no arguments
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// means it will user map's current center & resolution
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//
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return this.map.calculateBounds();
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},
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/**
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* APIMethod: getZoomForExtent
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*
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* Parameters:
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* bounds - {<OpenLayers.Bounds>}
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* closest - {Boolean} Find the zoom level that most closely fits the
|
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* specified bounds. Note that this may result in a zoom that does
|
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* not exactly contain the entire extent.
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* Default is false.
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*
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* Returns:
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* {Integer} The index of the zoomLevel (entry in the resolutions array)
|
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* for the passed-in extent. We do this by calculating the ideal
|
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* resolution for the given extent (based on the map size) and then
|
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* calling getZoomForResolution(), passing along the 'closest'
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* parameter.
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*/
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getZoomForExtent: function(extent, closest) {
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var viewSize = this.map.getSize();
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var idealResolution = Math.max( extent.getWidth() / viewSize.w,
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extent.getHeight() / viewSize.h );
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return this.getZoomForResolution(idealResolution, closest);
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},
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|
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/**
|
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* Method: getDataExtent
|
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* Calculates the max extent which includes all of the data for the layer.
|
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* This function is to be implemented by subclasses.
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*
|
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* Returns:
|
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* {<OpenLayers.Bounds>}
|
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*/
|
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getDataExtent: function () {
|
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//to be implemented by subclasses
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},
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|
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/**
|
|
* APIMethod: getZoomForResolution
|
|
*
|
|
* Parameters:
|
|
* resolution - {Float}
|
|
* closest - {Boolean} Find the zoom level that corresponds to the absolute
|
|
* closest resolution, which may result in a zoom whose corresponding
|
|
* resolution is actually smaller than we would have desired (if this
|
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* is being called from a getZoomForExtent() call, then this means that
|
|
* the returned zoom index might not actually contain the entire
|
|
* extent specified... but it'll be close).
|
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* Default is false.
|
|
*
|
|
* Returns:
|
|
* {Integer} The index of the zoomLevel (entry in the resolutions array)
|
|
* that corresponds to the best fit resolution given the passed in
|
|
* value and the 'closest' specification.
|
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*/
|
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getZoomForResolution: function(resolution, closest) {
|
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var diff;
|
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var minDiff = Number.POSITIVE_INFINITY;
|
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for(var i=0; i < this.resolutions.length; i++) {
|
|
if (closest) {
|
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diff = Math.abs(this.resolutions[i] - resolution);
|
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if (diff > minDiff) {
|
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break;
|
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}
|
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minDiff = diff;
|
|
} else {
|
|
if (this.resolutions[i] < resolution) {
|
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break;
|
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}
|
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}
|
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}
|
|
return Math.max(0, i-1);
|
|
},
|
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|
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/**
|
|
* APIMethod: getLonLatFromViewPortPx
|
|
*
|
|
* Parameters:
|
|
* viewPortPx - {<OpenLayers.Pixel>}
|
|
*
|
|
* Returns:
|
|
* {<OpenLayers.LonLat>} An OpenLayers.LonLat which is the passed-in
|
|
* view port <OpenLayers.Pixel>, translated into lon/lat by the layer.
|
|
*/
|
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getLonLatFromViewPortPx: function (viewPortPx) {
|
|
var lonlat = null;
|
|
if (viewPortPx != null) {
|
|
var size = this.map.getSize();
|
|
var center = this.map.getCenter();
|
|
if (center) {
|
|
var res = this.map.getResolution();
|
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|
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var delta_x = viewPortPx.x - (size.w / 2);
|
|
var delta_y = viewPortPx.y - (size.h / 2);
|
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|
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lonlat = new OpenLayers.LonLat(center.lon + delta_x * res ,
|
|
center.lat - delta_y * res);
|
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|
|
if (this.wrapDateLine) {
|
|
lonlat = lonlat.wrapDateLine(this.maxExtent);
|
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}
|
|
} // else { DEBUG STATEMENT }
|
|
}
|
|
return lonlat;
|
|
},
|
|
|
|
/**
|
|
* APIMethod: getViewPortPxFromLonLat
|
|
*
|
|
* Parameters:
|
|
* lonlat - {<OpenLayers.LonLat>}
|
|
*
|
|
* Returns:
|
|
* {<OpenLayers.Pixel>} An <OpenLayers.Pixel> which is the passed-in
|
|
* <OpenLayers.LonLat>,translated into view port pixels.
|
|
*/
|
|
getViewPortPxFromLonLat: function (lonlat) {
|
|
var px = null;
|
|
if (lonlat != null) {
|
|
var resolution = this.map.getResolution();
|
|
var extent = this.map.getExtent();
|
|
px = new OpenLayers.Pixel(
|
|
Math.round(1/resolution * (lonlat.lon - extent.left)),
|
|
Math.round(1/resolution * (extent.top - lonlat.lat))
|
|
);
|
|
}
|
|
return px;
|
|
},
|
|
|
|
/**
|
|
* APIMethod: setOpacity
|
|
* Sets the opacity for the entire layer (all images)
|
|
*
|
|
* Parameter:
|
|
* opacity - {Float}
|
|
*/
|
|
setOpacity: function(opacity) {
|
|
if (opacity != this.opacity) {
|
|
this.opacity = opacity;
|
|
for(var i=0; i<this.div.childNodes.length; ++i) {
|
|
var element = this.div.childNodes[i].firstChild;
|
|
OpenLayers.Util.modifyDOMElement(element, null, null, null,
|
|
null, null, null, opacity);
|
|
}
|
|
}
|
|
},
|
|
|
|
/**
|
|
* Method: setZIndex
|
|
*
|
|
* Parameters:
|
|
* zIndex - {Integer}
|
|
*/
|
|
setZIndex: function (zIndex) {
|
|
this.div.style.zIndex = zIndex;
|
|
},
|
|
|
|
/**
|
|
* Method: adjustBounds
|
|
* This function will take a bounds, and if wrapDateLine option is set
|
|
* on the layer, it will return a bounds which is wrapped around the
|
|
* world. We do not wrap for bounds which *cross* the
|
|
* maxExtent.left/right, only bounds which are entirely to the left
|
|
* or entirely to the right.
|
|
*
|
|
* Parameters:
|
|
* bounds - {<OpenLayers.Bounds>}
|
|
*/
|
|
adjustBounds: function (bounds) {
|
|
|
|
if (this.gutter) {
|
|
// Adjust the extent of a bounds in map units by the
|
|
// layer's gutter in pixels.
|
|
var mapGutter = this.gutter * this.map.getResolution();
|
|
bounds = new OpenLayers.Bounds(bounds.left - mapGutter,
|
|
bounds.bottom - mapGutter,
|
|
bounds.right + mapGutter,
|
|
bounds.top + mapGutter);
|
|
}
|
|
|
|
if (this.wrapDateLine) {
|
|
// wrap around the date line, within the limits of rounding error
|
|
var wrappingOptions = {
|
|
'rightTolerance':this.getResolution()
|
|
};
|
|
bounds = bounds.wrapDateLine(this.maxExtent, wrappingOptions);
|
|
|
|
}
|
|
return bounds;
|
|
},
|
|
|
|
CLASS_NAME: "OpenLayers.Layer"
|
|
});
|