/* 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/Control.js
* @requires OpenLayers/Layer/WMS/Post.js
* @requires OpenLayers/Handler/RegularPolygon.js
* @requires OpenLayers/Handler/Polygon.js
* @requires OpenLayers/Handler/Path.js
* @requires OpenLayers/Handler/Click.js
* @requires OpenLayers/Filter/Spatial.js
*/
/**
* Class: OpenLayers.Control.SLDSelect
* Perform selections on WMS layers using Styled Layer Descriptor (SLD)
*
* Inherits from:
* - <OpenLayers.Control>
*/
OpenLayers.Control.SLDSelect = OpenLayers.Class(OpenLayers.Control, {
/**
* Constant: EVENT_TYPES
* {Array(String)} Supported application event types. Register a listener
* for a particular event with the following syntax:
* (code)
* control.events.register(type, obj, listener);
* (end)
*
* Listeners will be called with a reference to an event object. The
* properties of this event depends on exactly what happened.
*
* Supported control event types (in addition to those from
* <OpenLayers.Control>):
* selected - Triggered when a selection occurs. Listeners receive an
* event with *filters* and *layer* properties. Filters will be an
* array of OpenLayers.Filter objects created in order to perform
* the particular selection.
*/
EVENT_TYPES: ["selected"],
/**
* APIProperty: clearOnDeactivate
* {Boolean} Should the selection be cleared when the control is
* deactivated. Default value is false.
*/
clearOnDeactivate: false,
/**
* APIProperty: layers
* {Array(<OpenLayers.Layer.WMS>)} The WMS layers this control will work
* on.
*/
layers: null,
/**
* Property: callbacks
* {Object} The functions that are sent to the handler for callback
*/
callbacks: null,
/**
* APIProperty: selectionSymbolizer
* {Object} Determines the styling of the selected objects. Default is
* a selection in red.
*/
selectionSymbolizer: {
'Polygon': {fillColor: '#FF0000', stroke: false},
'Line': {strokeColor: '#FF0000', strokeWidth: 2},
'Point': {graphicName: 'square', fillColor: '#FF0000', pointRadius: 5}
},
/**
* APIProperty: layerOptions
* {Object} The options to apply to the selection layer, by default the
* selection layer will be kept out of the layer switcher.
*/
layerOptions: null,
/**
* APIProperty: handlerOptions
* {Object} Used to set non-default properties on the control's handler
*/
handlerOptions: null,
/**
* APIProperty: sketchStyle
* {<OpenLayers.Style>|Object} Style or symbolizer to use for the sketch
* handler. The recommended way of styling the sketch layer, however, is
* to configure an <OpenLayers.StyleMap> in the layerOptions of the
* <handlerOptions>:
*
* (code)
* new OpenLayers.Control.SLDSelect(OpenLayers.Handler.Path, {
* handlerOptions: {
* layerOptions: {
* styleMap: new OpenLayers.StyleMap({
* "default": {strokeColor: "yellow"}
* });
* }
* }
* });
* (end)
*/
sketchStyle: null,
/**
* APIProperty: wfsCache
* {Object} Cache to use for storing parsed results from
* <OpenLayers.Format.WFSDescribeFeatureType.read>. If not provided,
* these will be cached on the prototype.
*/
wfsCache: {},
/**
* APIProperty: layerCache
* {Object} Cache to use for storing references to the selection layers.
* Normally each source layer will have exactly 1 selection layer of
* type OpenLayers.Layer.WMS.Post. If not provided, layers will
* be cached on the prototype. Note that if <clearOnDeactivate> is
* true, the layer will no longer be cached after deactivating the
* control.
*/
layerCache: {},
/**
* Constructor: OpenLayers.Control.SLDSelect
* Create a new control for selecting features in WMS layers using
* Styled Layer Descriptor (SLD).
*
* Parameters:
* handler - {<OpenLayers.Class>} A sketch handler class. This determines
* the type of selection, e.g. box (<OpenLayers.Handler.Box>), point
* (<OpenLayers.Handler.Point>), path (<OpenLayers.Handler.Path>) or
* polygon (<OpenLayers.Handler.Polygon>) selection. To use circle
* type selection, use <OpenLayers.Handler.RegularPolygon> and pass
* the number of desired sides (e.g. 40) as "sides" property to the
* <handlerOptions>.
* options - {Object} An object containing all configuration properties for
* the control.
*
* Valid options:
* layers - Array({<OpenLayers.Layer.WMS>}) The layers to perform the
* selection on.
*/
initialize: function(handler, options) {
// concatenate events specific to this control with those from the base
this.EVENT_TYPES =
OpenLayers.Control.SLDSelect.prototype.EVENT_TYPES.concat(
OpenLayers.Control.prototype.EVENT_TYPES
);
OpenLayers.Control.prototype.initialize.apply(this, [options]);
this.callbacks = OpenLayers.Util.extend({done: this.select,
click: this.select}, this.callbacks);
this.handlerOptions = this.handlerOptions || {};
this.layerOptions = OpenLayers.Util.applyDefaults(this.layerOptions, {
displayInLayerSwitcher: false
});
if (this.sketchStyle) {
this.handlerOptions.layerOptions = OpenLayers.Util.applyDefaults(
this.handlerOptions.layerOptions,
{styleMap: new OpenLayers.StyleMap({"default": this.sketchStyle})}
);
}
this.handler = new handler(this, this.callbacks, this.handlerOptions);
},
/**
* APIMethod: destroy
* Take care of things that are not handled in superclass.
*/
destroy: function() {
for (var key in this.layerCache) {
delete this.layerCache[key];
}
for (var key in this.wfsCache) {
delete this.wfsCache[key];
}
OpenLayers.Control.prototype.destroy.apply(this, arguments);
},
/**
* Method: coupleLayerVisiblity
* Couple the selection layer and the source layer with respect to
* layer visibility. So if the source layer is turned off, the
* selection layer is also turned off.
*
* Parameters:
* evt - {Object}
*/
coupleLayerVisiblity: function(evt) {
this.setVisibility(evt.object.getVisibility());
},
/**
* Method: createSelectionLayer
* Creates a "clone" from the source layer in which the selection can
* be drawn. This ensures both the source layer and the selection are
* visible and not only the selection.
*
* Parameters:
* source - {<OpenLayers.Layer.WMS>} The source layer on which the selection
* is performed.
*
* Returns:
* {<OpenLayers.Layer.WMS.Post>} A WMS Post layer since SLD selections can
* easily get quite long.
*/
createSelectionLayer: function(source) {
// check if we already have a selection layer for the source layer
var selectionLayer;
if (!this.layerCache[source.id]) {
selectionLayer = new OpenLayers.Layer.WMS.Post(source.name,
source.url, source.params,
OpenLayers.Util.applyDefaults(
this.layerOptions,
source.getOptions())
);
this.layerCache[source.id] = selectionLayer;
// make sure the layers are coupled wrt visibility, but only
// if they are not displayed in the layer switcher, because in
// that case the user cannot control visibility.
if (this.layerOptions.displayInLayerSwitcher === false) {
source.events.on({
"visibilitychanged": this.coupleLayerVisiblity,
scope: selectionLayer});
}
this.map.addLayer(selectionLayer);
} else {
selectionLayer = this.layerCache[source.id];
}
return selectionLayer;
},
/**
* Method: createSLD
* Create the SLD document for the layer using the supplied filters.
*
* Parameters:
* layer - {<OpenLayers.Layer.WMS>}
* filters - Array({<OpenLayers.Filter>}) The filters to be applied.
* geometryAttributes - Array({Object}) The geometry attributes of the
* layer.
*
* Returns:
* {String} The SLD document generated as a string.
*/
createSLD: function(layer, filters, geometryAttributes) {
var sld = {version: "1.0.0", namedLayers: {}};
var layerNames = [layer.params.LAYERS].join(",").split(",");
for (var i=0, len=layerNames.length; i<len; i++) {
var name = layerNames[i];
sld.namedLayers[name] = {name: name, userStyles: []};
var symbolizer = this.selectionSymbolizer;
var geometryAttribute = geometryAttributes[i];
if (geometryAttribute.type.indexOf('Polygon') >= 0) {
symbolizer = {Polygon: this.selectionSymbolizer['Polygon']};
} else if (geometryAttribute.type.indexOf('LineString') >= 0) {
symbolizer = {Line: this.selectionSymbolizer['Line']};
} else if (geometryAttribute.type.indexOf('Point') >= 0) {
symbolizer = {Point: this.selectionSymbolizer['Point']};
}
var filter = filters[i];
sld.namedLayers[name].userStyles.push({name: 'default', rules: [
new OpenLayers.Rule({symbolizer: symbolizer,
filter: filter,
maxScaleDenominator: layer.options.minScale})
]});
}
return new OpenLayers.Format.SLD().write(sld);
},
/**
* Method: parseDescribeLayer
* Parse the SLD WMS DescribeLayer response and issue the corresponding
* WFS DescribeFeatureType request
*
* request - {XMLHttpRequest} The request object.
*/
parseDescribeLayer: function(request) {
var format = new OpenLayers.Format.WMSDescribeLayer();
var doc = request.responseXML;
if(!doc || !doc.documentElement) {
doc = request.responseText;
}
var describeLayer = format.read(doc);
var typeNames = [];
var url = null;
for (var i=0, len=describeLayer.length; i<len; i++) {
// perform a WFS DescribeFeatureType request
if (describeLayer[i].owsType == "WFS") {
typeNames.push(describeLayer[i].typeName);
url = describeLayer[i].owsURL;
}
}
var options = {
url: url,
params: {
SERVICE: "WFS",
TYPENAME: typeNames.toString(),
REQUEST: "DescribeFeatureType",
VERSION: "1.0.0"
},
callback: function(request) {
var format = new OpenLayers.Format.WFSDescribeFeatureType();
var doc = request.responseXML;
if(!doc || !doc.documentElement) {
doc = request.responseText;
}
var describeFeatureType = format.read(doc);
this.control.wfsCache[this.layer.id] = describeFeatureType;
this.control._queue && this.control.applySelection();
},
scope: this
};
OpenLayers.Request.GET(options);
},
/**
* Method: getGeometryAttributes
* Look up the geometry attributes from the WFS DescribeFeatureType response
*
* Parameters:
* layer - {<OpenLayers.Layer.WMS>} The layer for which to look up the
* geometry attributes.
*
* Returns:
* Array({Object}) Array of geometry attributes
*/
getGeometryAttributes: function(layer) {
var result = [];
var cache = this.wfsCache[layer.id];
for (var i=0, len=cache.featureTypes.length; i<len; i++) {
var typeName = cache.featureTypes[i];
var properties = typeName.properties;
for (var j=0, lenj=properties.length; j < lenj; j++) {
var property = properties[j];
var type = property.type;
if ((type.indexOf('LineString') >= 0) ||
(type.indexOf('GeometryAssociationType') >=0) ||
(type.indexOf('GeometryPropertyType') >= 0) ||
(type.indexOf('Point') >= 0) ||
(type.indexOf('Polygon') >= 0) ) {
result.push(property);
}
}
}
return result;
},
/**
* APIMethod: activate
* Activate the control. Activating the control will perform a SLD WMS
* DescribeLayer request followed by a WFS DescribeFeatureType request
* so that the proper symbolizers can be chosen based on the geometry
* type.
*/
activate: function() {
var activated = OpenLayers.Control.prototype.activate.call(this);
if(activated) {
for (var i=0, len=this.layers.length; i<len; i++) {
var layer = this.layers[i];
if (layer && !this.wfsCache[layer.id]) {
var options = {
url: layer.url,
params: {
SERVICE: "WMS",
VERSION: layer.params.VERSION,
LAYERS: layer.params.LAYERS,
REQUEST: "DescribeLayer"
},
callback: this.parseDescribeLayer,
scope: {layer: layer, control: this}
};
OpenLayers.Request.GET(options);
}
}
}
return activated;
},
/**
* APIMethod: deactivate
* Deactivate the control. If clearOnDeactivate is true, remove the
* selection layer(s).
*/
deactivate: function() {
var deactivated = OpenLayers.Control.prototype.deactivate.call(this);
if(deactivated) {
for (var i=0, len=this.layers.length; i<len; i++) {
var layer = this.layers[i];
if (layer && this.clearOnDeactivate === true) {
var layerCache = this.layerCache;
var selectionLayer = layerCache[layer.id];
if (selectionLayer) {
layer.events.un({
"visibilitychanged": this.coupleLayerVisiblity,
scope: selectionLayer});
selectionLayer.destroy();
delete layerCache[layer.id];
}
}
}
}
return deactivated;
},
/**
* APIMethod: setLayers
* Set the layers on which the selection should be performed. Call the
* setLayers method if the layer(s) to be used change and the same
* control should be used on a new set of layers.
* If the control is already active, it will be active after the new
* set of layers is set.
*
* Parameters:
* layers - {Array(<OpenLayers.Layer.WMS>)} The new set of layers on which
* the selection should be performed.
*/
setLayers: function(layers) {
if(this.active) {
this.deactivate();
this.layers = layers;
this.activate();
} else {
this.layers = layers;
}
},
/**
* Function: createFilter
* Create the filter to be used in the SLD.
*
* Parameters:
* geometryAttribute - {Object} Used to get the name of the geometry
* attribute which is needed for constructing the spatial filter.
* geometry - {<OpenLayers.Geometry>} The geometry to use.
*
* Returns:
* {<OpenLayers.Filter.Spatial>} The spatial filter created.
*/
createFilter: function(geometryAttribute, geometry) {
var filter = null;
if (this.handler instanceof OpenLayers.Handler.RegularPolygon) {
// box
if (this.handler.irregular === true) {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.BBOX,
property: geometryAttribute.name,
value: geometry.getBounds()}
);
} else {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.INTERSECTS,
property: geometryAttribute.name,
value: geometry}
);
}
} else if (this.handler instanceof OpenLayers.Handler.Polygon) {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.INTERSECTS,
property: geometryAttribute.name,
value: geometry}
);
} else if (this.handler instanceof OpenLayers.Handler.Path) {
// if source layer is point based, use DWITHIN instead
if (geometryAttribute.type.indexOf('Point') >= 0) {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.DWITHIN,
property: geometryAttribute.name,
distance: this.map.getExtent().getWidth()*0.01 ,
distanceUnits: this.map.getUnits(),
value: geometry}
);
} else {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.INTERSECTS,
property: geometryAttribute.name,
value: geometry}
);
}
} else if (this.handler instanceof OpenLayers.Handler.Click) {
if (geometryAttribute.type.indexOf('Polygon') >= 0) {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.INTERSECTS,
property: geometryAttribute.name,
value: geometry}
);
} else {
filter = new OpenLayers.Filter.Spatial({
type: OpenLayers.Filter.Spatial.DWITHIN,
property: geometryAttribute.name,
distance: this.map.getExtent().getWidth()*0.01 ,
distanceUnits: this.map.getUnits(),
value: geometry}
);
}
}
return filter;
},
/**
* Method: select
* When the handler is done, use SLD_BODY on the selection layer to
* display the selection in the map.
*
* Parameters:
* geometry - {Object} or {<OpenLayers.Geometry>}
*/
select: function(geometry) {
this._queue = function() {
for (var i=0, len=this.layers.length; i<len; i++) {
var layer = this.layers[i];
var geometryAttributes = this.getGeometryAttributes(layer);
var filters = [];
for (var j=0, lenj=geometryAttributes.length; j<lenj; j++) {
var geometryAttribute = geometryAttributes[j];
if (geometryAttribute !== null) {
// from the click handler we will not get an actual
// geometry so transform
if (!(geometry instanceof OpenLayers.Geometry)) {
var point = this.map.getLonLatFromPixel(
geometry.xy);
geometry = new OpenLayers.Geometry.Point(
point.lon, point.lat);
}
var filter = this.createFilter(geometryAttribute,
geometry);
if (filter !== null) {
filters.push(filter);
}
}
}
var selectionLayer = this.createSelectionLayer(layer);
var sld = this.createSLD(layer, filters, geometryAttributes);
this.events.triggerEvent("selected", {
layer: layer,
filters: filters
});
selectionLayer.mergeNewParams({SLD_BODY: sld});
delete this._queue;
}
};
this.applySelection();
},
/**
* Method: applySelection
* Checks if all required wfs data is cached, and applies the selection
*/
applySelection: function() {
var canApply = true;
for (var i=0, len=this.layers.length; i<len; i++) {
if(!this.wfsCache[this.layers[i].id]) {
canApply = false;
break;
}
}
canApply && this._queue.call(this);
},
CLASS_NAME: "OpenLayers.Control.SLDSelect"
});