/* 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/Handler/Path.js
* @requires OpenLayers/Geometry/Polygon.js
*/
/**
* Class: OpenLayers.Handler.Polygon
* Handler to draw a polygon on the map. Polygon is displayed on mouse down,
* moves on mouse move, and is finished on mouse up.
*
* Inherits from:
* - <OpenLayers.Handler.Path>
* - <OpenLayers.Handler>
*/
OpenLayers.Handler.Polygon = OpenLayers.Class(OpenLayers.Handler.Path, {
/**
* Parameter: polygon
* {<OpenLayers.Feature.Vector>}
*/
polygon: null,
/**
* Constructor: OpenLayers.Handler.Polygon
* Create a Polygon Handler.
*
* Parameters:
* control - {<OpenLayers.Control>} The control that owns this handler
* callbacks - {Object} An object with a properties whose values are
* functions. Various callbacks described below.
* options - {Object} An optional object with properties to be set on the
* handler
*
* Named callbacks:
* create - Called when a sketch is first created. Callback called with
* the creation point geometry and sketch feature.
* modify - Called with each move of a vertex with the vertex (point)
* geometry and the sketch feature.
* point - Called as each point is added. Receives the new point geometry.
* done - Called when the point drawing is finished. The callback will
* recieve a single argument, the polygon geometry.
* cancel - Called when the handler is deactivated while drawing. The
* cancel callback will receive a geometry.
*/
initialize: function(control, callbacks, options) {
OpenLayers.Handler.Path.prototype.initialize.apply(this, arguments);
},
/**
* Method: createFeature
* Add temporary geometries
*
* Parameters:
* pixel - {<OpenLayers.Pixel>} The initial pixel location for the new
* feature.
*/
createFeature: function(pixel) {
var lonlat = this.control.map.getLonLatFromPixel(pixel);
this.point = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.Point(lonlat.lon, lonlat.lat)
);
this.line = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.LinearRing([this.point.geometry])
);
this.polygon = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.Polygon([this.line.geometry])
);
this.callback("create", [this.point.geometry, this.getSketch()]);
this.point.geometry.clearBounds();
this.layer.addFeatures([this.polygon, this.point], {silent: true});
},
/**
* Method: destroyFeature
* Destroy temporary geometries
*/
destroyFeature: function() {
OpenLayers.Handler.Path.prototype.destroyFeature.apply(this);
this.polygon = null;
},
/**
* Method: drawFeature
* Render geometries on the temporary layer.
*/
drawFeature: function() {
this.layer.drawFeature(this.polygon, this.style);
this.layer.drawFeature(this.point, this.style);
},
/**
* Method: getSketch
* Return the sketch feature.
*
* Returns:
* {<OpenLayers.Feature.Vector>}
*/
getSketch: function() {
return this.polygon;
},
/**
* Method: getGeometry
* Return the sketch geometry. If <multi> is true, this will return
* a multi-part geometry.
*
* Returns:
* {<OpenLayers.Geometry.Polygon>}
*/
getGeometry: function() {
var geometry = this.polygon && this.polygon.geometry;
if(geometry && this.multi) {
geometry = new OpenLayers.Geometry.MultiPolygon([geometry]);
}
return geometry;
},
/**
* Method: dblclick
* Handle double-clicks. Finish the geometry and send it back
* to the control.
*
* Parameters:
* evt - {Event}
*/
dblclick: function(evt) {
if(!this.freehandMode(evt)) {
// remove the penultimate point
var index = this.line.geometry.components.length - 2;
this.line.geometry.removeComponent(this.line.geometry.components[index]);
this.removePoint();
this.finalize();
}
return false;
},
CLASS_NAME: "OpenLayers.Handler.Polygon"
});