openlayers/lib/OpenLayers/Format/Text.js

   1 /* Copyright (c) 2006-2008 MetaCarta, Inc., published under a modified BSD license.
   2  * See http://svn.openlayers.org/trunk/openlayers/repository-license.txt
   3  * for the full text of the license. */
   4
   5 /**
   6  * @requires OpenLayers/Feature/Vector.js
   7  * @requires OpenLayers/Geometry/Point.js
   8  */
   9
  10 /**
  11  * Class: OpenLayers.Format.Text
  12  * Read Text format. Create a new instance with the <OpenLayers.Format.Text>
  13  *     constructor. This reads text which is formatted like CSV text, using
  14  *     tabs as the seperator by default. It provides parsing of data originally
  15  *     used in the MapViewerService, described on the wiki. This Format is used
  16  *     by the <OpenLayers.Layer.Text> class.
  17  *
  18  * Inherits from:
  19  *  - <OpenLayers.Format>
  20  */
  21 OpenLayers.Format.Text = OpenLayers.Class(OpenLayers.Format, {
  22
  23     /**
  24      * APIProperty: defaultStyle
  25      * defaultStyle allows one to control the default styling of the features.
  26      *    It should be a symbolizer hash. By default, this is set to match the
  27      *    Layer.Text behavior, which is to use the default OpenLayers Icon.
  28      */
  29     defaultStyle: null,
  30
  31     /**
  32      * APIProperty: extractStyles
  33      * set to true to extract styles from the TSV files, using information
  34      * from the image or icon, iconSize and iconOffset fields. This will result
  35      * in features with a symbolizer (style) property set, using the
  36      * default symbolizer specified in <defaultStyle>. Set to false if you
  37      * wish to use a styleMap or OpenLayers.Style options to style your
  38      * layer instead.
  39      */
  40     extractStyles: true,
  41
  42     /**
  43      * Constructor: OpenLayers.Format.Text
  44      * Create a new parser for TSV Text.
  45      *
  46      * Parameters:
  47      * options - {Object} An optional object whose properties will be set on
  48      *     this instance.
  49      */
  50     initialize: function(options) {
  51         options = options || {};
  52
  53         if(options.extractStyles !== false) {
  54             options.defaultStyle = {
  55                 'externalGraphic': OpenLayers.Util.getImagesLocation() +
  56                                                                 "marker.png",
  57                 'graphicWidth': 21,
  58                 'graphicHeight': 25,
  59                 'graphicXOffset': -10.5,
  60                 'graphicYOffset': -12.5
  61             };
  62         }
  63
  64         OpenLayers.Format.prototype.initialize.apply(this, [options]);
  65     },
  66
  67     /**
  68      * APIMethod: read
  69      * Return a list of features from a Tab Seperated Values text string.
  70      *
  71      * Parameters:
  72      * data - {String}
  73      *
  74      * Returns:
  75      * An Array of <OpenLayers.Feature.Vector>s
  76      */
  77     read: function(text) {
  78         var lines = text.split('\n');
  79         var columns;
  80         var features = [];
  81         // length - 1 to allow for trailing new line
  82         for (var lcv = 0; lcv < (lines.length - 1); lcv++) {
  83             var currLine = lines[lcv].replace(/^\s*/,'').replace(/\s*$/,'');
  84
  85             if (currLine.charAt(0) != '#') { /* not a comment */
  86
  87                 if (!columns) {
  88                     //First line is columns
  89                     columns = currLine.split('\t');
  90                 } else {
  91                     var vals = currLine.split('\t');
  92                     var geometry = new OpenLayers.Geometry.Point(0,0);
  93                     var attributes = {};
  94                     var style = this.defaultStyle ?
  95                         OpenLayers.Util.applyDefaults({}, this.defaultStyle) :
  96                         null;
  97                     var icon, iconSize, iconOffset, overflow;
  98                     var set = false;
  99                     for (var valIndex = 0; valIndex < vals.length; valIndex++) {
 100                         if (vals[valIndex]) {
 101                             if (columns[valIndex] == 'point') {
 102                                 var coords = vals[valIndex].split(',');
 103                                 geometry.y = parseFloat(coords[0]);
 104                                 geometry.x = parseFloat(coords[1]);
 105                                 set = true;
 106                             } else if (columns[valIndex] == 'lat') {
 107                                 geometry.y = parseFloat(vals[valIndex]);
 108                                 set = true;
 109                             } else if (columns[valIndex] == 'lon') {
 110                                 geometry.x = parseFloat(vals[valIndex]);
 111                                 set = true;
 112                             } else if (columns[valIndex] == 'title')
 113                                 attributes['title'] = vals[valIndex];
 114                             else if (columns[valIndex] == 'image' ||
 115                                      columns[valIndex] == 'icon' && style) {
 116                                 style['externalGraphic'] = vals[valIndex];
 117                             } else if (columns[valIndex] == 'iconSize' && style) {
 118                                 var size = vals[valIndex].split(',');
 119                                 style['graphicWidth'] = parseFloat(size[0]);
 120                                 style['graphicHeight'] = parseFloat(size[1]);
 121                             } else if (columns[valIndex] == 'iconOffset' && style) {
 122                                 var offset = vals[valIndex].split(',');
 123                                 style['graphicXOffset'] = parseFloat(offset[0]);
 124                                 style['graphicYOffset'] = parseFloat(offset[1]);
 125                             } else if (columns[valIndex] == 'description') {
 126                                 attributes['description'] = vals[valIndex];
 127                             } else if (columns[valIndex] == 'overflow') {
 128                                 attributes['overflow'] = vals[valIndex];
 129                             } else {
 130                                 // For StyleMap filtering, allow additional
 131                                 // columns to be stored as attributes.
 132                                 attributes[columns[valIndex]] = vals[valIndex];
 133                             }
 134                         }
 135                     }
 136                     if (set) {
 137                       if (this.internalProjection && this.externalProjection) {
 138                           geometry.transform(this.externalProjection,
 139                                              this.internalProjection);
 140                       }
 141                       var feature = new OpenLayers.Feature.Vector(geometry, attributes, style);
 142                       features.push(feature);
 143                     }
 144                 }
 145             }
 146         }
 147         return features;
 148     },
 149
 150     CLASS_NAME: "OpenLayers.Format.Text"
 151 });