openlayers/lib/OpenLayers/Filter/Spatial.js

   1 /* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
   2  * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
   3   * full text of the license. */
   4
   5 /**
   6  * @requires OpenLayers/Filter.js
   7  * @requires OpenLayers/Console.js
   8  */
   9
  10 /**
  11  * Class: OpenLayers.Filter.Spatial
  12  * This class represents a spatial filter.
  13  * Currently implemented: BBOX, DWithin and Intersects
  14  *
  15  * Inherits from
  16  * - <OpenLayers.Filter>
  17  */
  18 OpenLayers.Filter.Spatial = OpenLayers.Class(OpenLayers.Filter, {
  19
  20     /**
  21      * APIProperty: type
  22      * {String} Type of spatial filter.
  23      *
  24      * The type should be one of:
  25      * - OpenLayers.Filter.Spatial.BBOX
  26      * - OpenLayers.Filter.Spatial.INTERSECTS
  27      * - OpenLayers.Filter.Spatial.DWITHIN
  28      * - OpenLayers.Filter.Spatial.WITHIN
  29      * - OpenLayers.Filter.Spatial.CONTAINS
  30      */
  31     type: null,
  32
  33     /**
  34      * APIProperty: property
  35      * {String} Name of the context property to compare.
  36      */
  37     property: null,
  38
  39     /**
  40      * APIProperty: value
  41      * {<OpenLayers.Bounds> || <OpenLayers.Geometry>} The bounds or geometry
  42      *     to be used by the filter.  Use bounds for BBOX filters and geometry
  43      *     for INTERSECTS or DWITHIN filters.
  44      */
  45     value: null,
  46
  47     /**
  48      * APIProperty: distance
  49      * {Number} The distance to use in a DWithin spatial filter.
  50      */
  51     distance: null,
  52
  53     /**
  54      * APIProperty: distanceUnits
  55      * {String} The units to use for the distance, e.g. 'm'.
  56      */
  57     distanceUnits: null,
  58
  59     /**
  60      * Constructor: OpenLayers.Filter.Spatial
  61      * Creates a spatial filter.
  62      *
  63      * Parameters:
  64      * options - {Object} An optional object with properties to set on the
  65      *     filter.
  66      *
  67      * Returns:
  68      * {<OpenLayers.Filter.Spatial>}
  69      */
  70     initialize: function(options) {
  71         OpenLayers.Filter.prototype.initialize.apply(this, [options]);
  72     },
  73
  74    /**
  75     * Method: evaluate
  76     * Evaluates this filter for a specific feature.
  77     *
  78     * Parameters:
  79     * feature - {<OpenLayers.Feature.Vector>} feature to apply the filter to.
  80     *
  81     * Returns:
  82     * {Boolean} The feature meets filter criteria.
  83     */
  84     evaluate: function(feature) {
  85         var intersect = false;
  86         switch(this.type) {
  87             case OpenLayers.Filter.Spatial.BBOX:
  88             case OpenLayers.Filter.Spatial.INTERSECTS:
  89                 if(feature.geometry) {
  90                     var geom = this.value;
  91                     if(this.value.CLASS_NAME == "OpenLayers.Bounds") {
  92                         geom = this.value.toGeometry();
  93                     }
  94                     if(feature.geometry.intersects(geom)) {
  95                         intersect = true;
  96                     }
  97                 }
  98                 break;
  99             default:
 100                 OpenLayers.Console.error(
 101                     OpenLayers.i18n("filterEvaluateNotImplemented"));
 102                 break;
 103         }
 104         return intersect;
 105     },
 106
 107     /**
 108      * APIMethod: clone
 109      * Clones this filter.
 110      *
 111      * Returns:
 112      * {<OpenLayers.Filter.Spatial>} Clone of this filter.
 113      */
 114     clone: function() {
 115         var options = OpenLayers.Util.applyDefaults({
 116             value: this.value && this.value.clone && this.value.clone()
 117         }, this);
 118         return new OpenLayers.Filter.Spatial(options);
 119     },
 120     CLASS_NAME: "OpenLayers.Filter.Spatial"
 121 });
 122
 123 OpenLayers.Filter.Spatial.BBOX = "BBOX";
 124 OpenLayers.Filter.Spatial.INTERSECTS = "INTERSECTS";
 125 OpenLayers.Filter.Spatial.DWITHIN = "DWITHIN";
 126 OpenLayers.Filter.Spatial.WITHIN = "WITHIN";
 127 OpenLayers.Filter.Spatial.CONTAINS = "CONTAINS";