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Diffstat (limited to 'misc/openlayers/lib/OpenLayers/Layer/FixedZoomLevels.js')
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Layer/FixedZoomLevels.js | 319 |
1 files changed, 0 insertions, 319 deletions
diff --git a/misc/openlayers/lib/OpenLayers/Layer/FixedZoomLevels.js b/misc/openlayers/lib/OpenLayers/Layer/FixedZoomLevels.js deleted file mode 100644 index f647238..0000000 --- a/misc/openlayers/lib/OpenLayers/Layer/FixedZoomLevels.js +++ /dev/null @@ -1,319 +0,0 @@ -/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for - * full list of contributors). Published under the 2-clause BSD license. - * See license.txt in the OpenLayers distribution or repository for the - * full text of the license. */ - -/** - * @requires OpenLayers/Layer.js - */ - -/** - * Class: OpenLayers.Layer.FixedZoomLevels - * Some Layers will already have established zoom levels (like google - * or ve). Instead of trying to determine them and populate a resolutions[] - * Array with those values, we will hijack the resolution functionality - * here. - * - * When you subclass FixedZoomLevels: - * - * The initResolutions() call gets nullified, meaning no resolutions[] array - * is set up. Which would be a big problem getResolution() in Layer, since - * it merely takes map.zoom and indexes into resolutions[]... but.... - * - * The getResolution() call is also overridden. Instead of using the - * resolutions[] array, we simply calculate the current resolution based - * on the current extent and the current map size. But how will we be able - * to calculate the current extent without knowing the resolution...? - * - * The getExtent() function is also overridden. Instead of calculating extent - * based on the center point and the current resolution, we instead - * calculate the extent by getting the lonlats at the top-left and - * bottom-right by using the getLonLatFromViewPortPx() translation function, - * taken from the pixel locations (0,0) and the size of the map. But how - * will we be able to do lonlat-px translation without resolution....? - * - * The getZoomForResolution() method is overridden. Instead of indexing into - * the resolutions[] array, we call OpenLayers.Layer.getExent(), passing in - * the desired resolution. With this extent, we then call getZoomForExtent() - * - * - * Whenever you implement a layer using OpenLayers.Layer.FixedZoomLevels, - * it is your responsibility to provide the following three functions: - * - * - getLonLatFromViewPortPx - * - getViewPortPxFromLonLat - * - getZoomForExtent - * - * ...those three functions should generally be provided by any reasonable - * API that you might be working from. - * - */ -OpenLayers.Layer.FixedZoomLevels = OpenLayers.Class({ - - /********************************************************/ - /* */ - /* Baselayer Functions */ - /* */ - /* The following functions must all be implemented */ - /* by all base layers */ - /* */ - /********************************************************/ - - /** - * Constructor: OpenLayers.Layer.FixedZoomLevels - * Create a new fixed zoom levels layer. - */ - initialize: function() { - //this class is only just to add the following functions... - // nothing to actually do here... but it is probably a good - // idea to have layers that use these functions call this - // inititalize() anyways, in case at some point we decide we - // do want to put some functionality or state in here. - }, - - /** - * Method: initResolutions - * Populate the resolutions array - */ - initResolutions: function() { - - var props = ['minZoomLevel', 'maxZoomLevel', 'numZoomLevels']; - - for(var i=0, len=props.length; i<len; i++) { - var property = props[i]; - this[property] = (this.options[property] != null) - ? this.options[property] - : this.map[property]; - } - - if ( (this.minZoomLevel == null) || - (this.minZoomLevel < this.MIN_ZOOM_LEVEL) ){ - this.minZoomLevel = this.MIN_ZOOM_LEVEL; - } - - // - // At this point, we know what the minimum desired zoom level is, and - // we must calculate the total number of zoom levels. - // - // Because we allow for the setting of either the 'numZoomLevels' - // or the 'maxZoomLevel' properties... on either the layer or the - // map, we have to define some rules to see which we take into - // account first in this calculation. - // - // The following is the precedence list for these properties: - // - // (1) numZoomLevels set on layer - // (2) maxZoomLevel set on layer - // (3) numZoomLevels set on map - // (4) maxZoomLevel set on map* - // (5) none of the above* - // - // *Note that options (4) and (5) are only possible if the user - // _explicitly_ sets the 'numZoomLevels' property on the map to - // null, since it is set by default to 16. - // - - // - // Note to future: In 3.0, I think we should remove the default - // value of 16 for map.numZoomLevels. Rather, I think that value - // should be set as a default on the Layer.WMS class. If someone - // creates a 3rd party layer and does not specify any 'minZoomLevel', - // 'maxZoomLevel', or 'numZoomLevels', and has not explicitly - // specified any of those on the map object either.. then I think - // it is fair to say that s/he wants all the zoom levels available. - // - // By making map.numZoomLevels *null* by default, that will be the - // case. As it is, I don't feel comfortable changing that right now - // as it would be a glaring API change and actually would probably - // break many peoples' codes. - // - - //the number of zoom levels we'd like to have. - var desiredZoomLevels; - - //this is the maximum number of zoom levels the layer will allow, - // given the specified starting minimum zoom level. - var limitZoomLevels = this.MAX_ZOOM_LEVEL - this.minZoomLevel + 1; - - if ( ((this.options.numZoomLevels == null) && - (this.options.maxZoomLevel != null)) // (2) - || - ((this.numZoomLevels == null) && - (this.maxZoomLevel != null)) // (4) - ) { - //calculate based on specified maxZoomLevel (on layer or map) - desiredZoomLevels = this.maxZoomLevel - this.minZoomLevel + 1; - } else { - //calculate based on specified numZoomLevels (on layer or map) - // this covers cases (1) and (3) - desiredZoomLevels = this.numZoomLevels; - } - - if (desiredZoomLevels != null) { - //Now that we know what we would *like* the number of zoom levels - // to be, based on layer or map options, we have to make sure that - // it does not conflict with the actual limit, as specified by - // the constants on the layer itself (and calculated into the - // 'limitZoomLevels' variable). - this.numZoomLevels = Math.min(desiredZoomLevels, limitZoomLevels); - } else { - // case (5) -- neither 'numZoomLevels' not 'maxZoomLevel' was - // set on either the layer or the map. So we just use the - // maximum limit as calculated by the layer's constants. - this.numZoomLevels = limitZoomLevels; - } - - //now that the 'numZoomLevels' is appropriately, safely set, - // we go back and re-calculate the 'maxZoomLevel'. - this.maxZoomLevel = this.minZoomLevel + this.numZoomLevels - 1; - - if (this.RESOLUTIONS != null) { - var resolutionsIndex = 0; - this.resolutions = []; - for(var i= this.minZoomLevel; i <= this.maxZoomLevel; i++) { - this.resolutions[resolutionsIndex++] = this.RESOLUTIONS[i]; - } - this.maxResolution = this.resolutions[0]; - this.minResolution = this.resolutions[this.resolutions.length - 1]; - } - }, - - /** - * APIMethod: getResolution - * Get the current map resolution - * - * Returns: - * {Float} Map units per Pixel - */ - getResolution: function() { - - if (this.resolutions != null) { - return OpenLayers.Layer.prototype.getResolution.apply(this, arguments); - } else { - var resolution = null; - - var viewSize = this.map.getSize(); - var extent = this.getExtent(); - - if ((viewSize != null) && (extent != null)) { - resolution = Math.max( extent.getWidth() / viewSize.w, - extent.getHeight() / viewSize.h ); - } - return resolution; - } - }, - - /** - * APIMethod: getExtent - * Calculates using px-> lonlat translation functions on tl and br - * corners of viewport - * - * Returns: - * {<OpenLayers.Bounds>} A Bounds object which represents the lon/lat - * bounds of the current viewPort. - */ - getExtent: function () { - var size = this.map.getSize(); - var tl = this.getLonLatFromViewPortPx({ - x: 0, y: 0 - }); - var br = this.getLonLatFromViewPortPx({ - x: size.w, y: size.h - }); - - if ((tl != null) && (br != null)) { - return new OpenLayers.Bounds(tl.lon, br.lat, br.lon, tl.lat); - } else { - return null; - } - }, - - /** - * Method: getZoomForResolution - * Get the zoom level for a given resolution - * - * Parameters: - * resolution - {Float} - * - * Returns: - * {Integer} A suitable zoom level for the specified resolution. - * If no baselayer is set, returns null. - */ - getZoomForResolution: function(resolution) { - - if (this.resolutions != null) { - return OpenLayers.Layer.prototype.getZoomForResolution.apply(this, arguments); - } else { - var extent = OpenLayers.Layer.prototype.getExtent.apply(this, []); - return this.getZoomForExtent(extent); - } - }, - - - - - /********************************************************/ - /* */ - /* Translation Functions */ - /* */ - /* The following functions translate GMaps and OL */ - /* formats for Pixel, LonLat, Bounds, and Zoom */ - /* */ - /********************************************************/ - - - // - // TRANSLATION: MapObject Zoom <-> OpenLayers Zoom - // - - /** - * Method: getOLZoomFromMapObjectZoom - * Get the OL zoom index from the map object zoom level - * - * Parameters: - * moZoom - {Integer} - * - * Returns: - * {Integer} An OpenLayers Zoom level, translated from the passed in zoom - * Returns null if null value is passed in - */ - getOLZoomFromMapObjectZoom: function(moZoom) { - var zoom = null; - if (moZoom != null) { - zoom = moZoom - this.minZoomLevel; - if (this.map.baseLayer !== this) { - zoom = this.map.baseLayer.getZoomForResolution( - this.getResolutionForZoom(zoom) - ); - } - } - return zoom; - }, - - /** - * Method: getMapObjectZoomFromOLZoom - * Get the map object zoom level from the OL zoom level - * - * Parameters: - * olZoom - {Integer} - * - * Returns: - * {Integer} A MapObject level, translated from the passed in olZoom - * Returns null if null value is passed in - */ - getMapObjectZoomFromOLZoom: function(olZoom) { - var zoom = null; - if (olZoom != null) { - zoom = olZoom + this.minZoomLevel; - if (this.map.baseLayer !== this) { - zoom = this.getZoomForResolution( - this.map.baseLayer.getResolutionForZoom(zoom) - ); - } - } - return zoom; - }, - - CLASS_NAME: "OpenLayers.Layer.FixedZoomLevels" -}); - |