--- a/labs/openlayers/lib/OpenLayers/Format/OSM.js +++ b/labs/openlayers/lib/OpenLayers/Format/OSM.js @@ -1,1 +1,458 @@ - +/* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for + * full list of contributors). Published under the Clear BSD license. + * See http://svn.openlayers.org/trunk/openlayers/license.txt for the + * full text of the license. */ + +/** + * @requires OpenLayers/Format/XML.js + * @requires OpenLayers/Feature/Vector.js + * @requires OpenLayers/Geometry/Point.js + * @requires OpenLayers/Geometry/LineString.js + * @requires OpenLayers/Geometry/Polygon.js + * @requires OpenLayers/Projection.js + */ + +/** + * Class: OpenLayers.Format.OSM + * OSM parser. Create a new instance with the + * <OpenLayers.Format.OSM> constructor. + * + * Inherits from: + * - <OpenLayers.Format.XML> + */ +OpenLayers.Format.OSM = OpenLayers.Class(OpenLayers.Format.XML, { + + /** + * APIProperty: checkTags + * {Boolean} Should tags be checked to determine whether something + * should be treated as a seperate node. Will slow down parsing. + * Default is false. + */ + checkTags: false, + + /** + * Property: interestingTagsExclude + * {Array} List of tags to exclude from 'interesting' checks on nodes. + * Must be set when creating the format. Will only be used if checkTags + * is set. + */ + interestingTagsExclude: null, + + /** + * APIProperty: areaTags + * {Array} List of tags indicating that something is an area. + * Must be set when creating the format. Will only be used if + * checkTags is true. + */ + areaTags: null, + + /** + * Constructor: OpenLayers.Format.OSM + * Create a new parser for OSM. + * + * Parameters: + * options - {Object} An optional object whose properties will be set on + * this instance. + */ + initialize: function(options) { + var layer_defaults = { + 'interestingTagsExclude': ['source', 'source_ref', + 'source:ref', 'history', 'attribution', 'created_by'], + 'areaTags': ['area', 'building', 'leisure', 'tourism', 'ruins', + 'historic', 'landuse', 'military', 'natural', 'sport'] + }; + + layer_defaults = OpenLayers.Util.extend(layer_defaults, options); + + var interesting = {}; + for (var i = 0; i < layer_defaults.interestingTagsExclude.length; i++) { + interesting[layer_defaults.interestingTagsExclude[i]] = true; + } + layer_defaults.interestingTagsExclude = interesting; + + var area = {}; + for (var i = 0; i < layer_defaults.areaTags.length; i++) { + area[layer_defaults.areaTags[i]] = true; + } + layer_defaults.areaTags = area; + + // OSM coordinates are always in longlat WGS84 + this.externalProjection = new OpenLayers.Projection("EPSG:4326"); + + OpenLayers.Format.XML.prototype.initialize.apply(this, [layer_defaults]); + }, + + /** + * APIMethod: read + * Return a list of features from a OSM doc + + * Parameters: + * data - {Element} + * + * Returns: + * An Array of <OpenLayers.Feature.Vector>s + */ + read: function(doc) { + if (typeof doc == "string") { + doc = OpenLayers.Format.XML.prototype.read.apply(this, [doc]); + } + + var nodes = this.getNodes(doc); + var ways = this.getWays(doc); + + // Geoms will contain at least ways.length entries. + var feat_list = new Array(ways.length); + + for (var i = 0; i < ways.length; i++) { + // We know the minimal of this one ahead of time. (Could be -1 + // due to areas/polygons) + var point_list = new Array(ways[i].nodes.length); + + var poly = this.isWayArea(ways[i]) ? 1 : 0; + for (var j = 0; j < ways[i].nodes.length; j++) { + var node = nodes[ways[i].nodes[j]]; + + var point = new OpenLayers.Geometry.Point(node.lon, node.lat); + + // Since OSM is topological, we stash the node ID internally. + point.osm_id = parseInt(ways[i].nodes[j]); + point_list[j] = point; + + // We don't display nodes if they're used inside other + // elements. + node.used = true; + } + var geometry = null; + if (poly) { + geometry = new OpenLayers.Geometry.Polygon( + new OpenLayers.Geometry.LinearRing(point_list)); + } else { + geometry = new OpenLayers.Geometry.LineString(point_list); + } + if (this.internalProjection && this.externalProjection) { + geometry.transform(this.externalProjection, + this.internalProjection); + } + var feat = new OpenLayers.Feature.Vector(geometry, + ways[i].tags); + feat.osm_id = parseInt(ways[i].id); + feat.fid = "way." + feat.osm_id; + feat_list[i] = feat; + } + for (var node_id in nodes) { + var node = nodes[node_id]; + if (!node.used || this.checkTags) { + var tags = null; + + if (this.checkTags) { + var result = this.getTags(node.node, true); + if (node.used && !result[1]) { + continue; + } + tags = result[0]; + } else { + tags = this.getTags(node.node); + } + + var feat = new OpenLayers.Feature.Vector( + new OpenLayers.Geometry.Point(node['lon'], node['lat']), + tags); + if (this.internalProjection && this.externalProjection) { + feat.geometry.transform(this.externalProjection, + this.internalProjection); + } + feat.osm_id = parseInt(node_id); + feat.fid = "node." + feat.osm_id; + feat_list.push(feat); + } + // Memory cleanup + node.node = null; + } + return feat_list; + }, + + /** + * Method: getNodes + * Return the node items from a doc. + * + * Parameters: + * node - {DOMElement} node to parse tags from + */ + getNodes: function(doc) { + var node_list = doc.getElementsByTagName("node"); + var nodes = {}; + for (var i = 0; i < node_list.length; i++) { + var node = node_list[i]; + var id = node.getAttribute("id"); + nodes[id] = { + 'lat': node.getAttribute("lat"), + 'lon': node.getAttribute("lon"), + 'node': node + }; + } + return nodes; + }, + + /** + * Method: getWays + * Return the way items from a doc. + * + * Parameters: + * node - {DOMElement} node to parse tags from + */ + getWays: function(doc) { + var way_list = doc.getElementsByTagName("way"); + var return_ways = []; + for (var i = 0; i < way_list.length; i++) { + var way = way_list[i]; + var way_object = { + id: way.getAttribute("id") + }; + + way_object.tags = this.getTags(way); + + var node_list = way.getElementsByTagName("nd"); + + way_object.nodes = new Array(node_list.length); + + for (var j = 0; j < node_list.length; j++) { + way_object.nodes[j] = node_list[j].getAttribute("ref"); + } + return_ways.push(way_object); + } + return return_ways; + + }, + + /** + * Method: getTags + * Return the tags list attached to a specific DOM element. + * + * Parameters: + * node - {DOMElement} node to parse tags from + * interesting_tags - {Boolean} whether the return from this function should + * return a boolean indicating that it has 'interesting tags' -- + * tags like attribution and source are ignored. (To change the list + * of tags, see interestingTagsExclude) + * + * Returns: + * tags - {Object} hash of tags + * interesting - {Boolean} if interesting_tags is passed, returns + * whether there are any interesting tags on this element. + */ + getTags: function(dom_node, interesting_tags) { + var tag_list = dom_node.getElementsByTagName("tag"); + var tags = {}; + var interesting = false; + for (var j = 0; j < tag_list.length; j++) { + var key = tag_list[j].getAttribute("k"); + tags[key] = tag_list[j].getAttribute("v"); + if (interesting_tags) { + if (!this.interestingTagsExclude[key]) { + interesting = true; + } + } + } + return interesting_tags ? [tags, interesting] : tags; + }, + + /** + * Method: isWayArea + * Given a way object from getWays, check whether the tags and geometry + * indicate something is an area. + * + * Returns: + * {Boolean} + */ + isWayArea: function(way) { + var poly_shaped = false; + var poly_tags = false; + + if (way.nodes[0] == way.nodes[way.nodes.length - 1]) { + poly_shaped = true; + } + if (this.checkTags) { + for(var key in way.tags) { + if (this.areaTags[key]) { + poly_tags = true; + break; + } + } + } + return poly_shaped && (this.checkTags ? poly_tags : true); + }, + + /** + * APIMethod: write + * Takes a list of features, returns a serialized OSM format file for use + * in tools like JOSM. + * + * Parameters: + * features - {Array(<OpenLayers.Feature.Vector>)} + */ + write: function(features) { + if (!(features instanceof Array)) { + features = [features]; + } + + this.osm_id = 1; + this.created_nodes = {}; + var root_node = this.createElementNS(null, "osm"); + root_node.setAttribute("version", "0.5"); + root_node.setAttribute("generator", "OpenLayers "+ OpenLayers.VERSION_NUMBER); + + // Loop backwards, because the deserializer puts nodes last, and + // we want them first if possible + for(var i = features.length - 1; i >= 0; i--) { + var nodes = this.createFeatureNodes(features[i]); + for (var j = 0; j < nodes.length; j++) { + root_node.appendChild(nodes[j]); + } + } + return OpenLayers.Format.XML.prototype.write.apply(this, [root_node]); + }, + + /** + * Method: createFeatureNodes + * Takes a feature, returns a list of nodes from size 0->n. + * Will include all pieces of the serialization that are required which + * have not already been created. Calls out to createXML based on geometry + * type. + * + * Parameters: + * feature - {<OpenLayers.Feature.Vector>} + */ + createFeatureNodes: function(feature) { + var nodes = []; + var className = feature.geometry.CLASS_NAME; + var type = className.substring(className.lastIndexOf(".") + 1); + type = type.toLowerCase(); + var builder = this.createXML[type]; + if (builder) { + nodes = builder.apply(this, [feature]); + } + return nodes; + }, + + /** + * Method: createXML + * Takes a feature, returns a list of nodes from size 0->n. + * Will include all pieces of the serialization that are required which + * have not already been created. + * + * Parameters: + * feature - {<OpenLayers.Feature.Vector>} + */ + createXML: { + 'point': function(point) { + var id = null; + var geometry = point.geometry ? point.geometry : point; + var already_exists = false; // We don't return anything if the node + // has already been created + if (point.osm_id) { + id = point.osm_id; + if (this.created_nodes[id]) { + already_exists = true; + } + } else { + id = -this.osm_id; + this.osm_id++; + } + if (already_exists) { + node = this.created_nodes[id]; + } else { + var node = this.createElementNS(null, "node"); + } + this.created_nodes[id] = node; + node.setAttribute("id", id); + node.setAttribute("lon", geometry.x); + node.setAttribute("lat", geometry.y); + if (point.attributes) { + this.serializeTags(point, node); + } + this.setState(point, node); + return already_exists ? [] : [node]; + }, + linestring: function(feature) { + var nodes = []; + var geometry = feature.geometry; + if (feature.osm_id) { + id = feature.osm_id; + } else { + id = -this.osm_id; + this.osm_id++; + } + var way = this.createElementNS(null, "way"); + way.setAttribute("id", id); + for (var i = 0; i < geometry.components.length; i++) { + var node = this.createXML['point'].apply(this, [geometry.components[i]]); + if (node.length) { + node = node[0]; + var node_ref = node.getAttribute("id"); + nodes.push(node); + } else { + node_ref = geometry.components[i].osm_id; + node = this.created_nodes[node_ref]; + } + this.setState(feature, node); + var nd_dom = this.createElementNS(null, "nd"); + nd_dom.setAttribute("ref", node_ref); + way.appendChild(nd_dom); + } + this.serializeTags(feature, way); + nodes.push(way); + + return nodes; + }, + polygon: function(feature) { + var attrs = OpenLayers.Util.extend({'area':'yes'}, feature.attributes); + var feat = new OpenLayers.Feature.Vector(feature.geometry.components[0], attrs); + feat.osm_id = feature.osm_id; + return this.createXML['linestring'].apply(this, [feat]); + } + }, + + /** + * Method: serializeTags + * Given a feature, serialize the attributes onto the given node. + * + * Parameters: + * feature - {<OpenLayers.Feature.Vector>} + * node - {DOMNode} + */ + serializeTags: function(feature, node) { + for (var key in feature.attributes) { + var tag = this.createElementNS(null, "tag"); + tag.setAttribute("k", key); + tag.setAttribute("v", feature.attributes[key]); + node.appendChild(tag); + } + }, + + /** + * Method: setState + * OpenStreetMap has a convention that 'state' is stored for modification or deletion. + * This allows the file to be uploaded via JOSM or the bulk uploader tool. + * + * Parameters: + * feature - {<OpenLayers.Feature.Vector>} + * node - {DOMNode} + */ + setState: function(feature, node) { + if (feature.state) { + var state = null; + switch(feature.state) { + case OpenLayers.State.UPDATE: + state = "modify"; + case OpenLayers.State.DELETE: + state = "delete"; + } + if (state) { + node.setAttribute("action", state); + } + } + }, + + CLASS_NAME: "OpenLayers.Format.OSM" +}); +