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Diffstat (limited to 'misc/openlayers/lib/OpenLayers/Control/Measure.js')
| -rw-r--r-- | misc/openlayers/lib/OpenLayers/Control/Measure.js | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/misc/openlayers/lib/OpenLayers/Control/Measure.js b/misc/openlayers/lib/OpenLayers/Control/Measure.js new file mode 100644 index 0000000..03c22b8 --- /dev/null +++ b/misc/openlayers/lib/OpenLayers/Control/Measure.js @@ -0,0 +1,379 @@ +/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for + * full list of contributors). Published under the 2-clause BSD license. + * See license.txt in the OpenLayers distribution or repository for the + * full text of the license. */ + +/** + * @requires OpenLayers/Control.js + * @requires OpenLayers/Feature/Vector.js + */ + +/** + * Class: OpenLayers.Control.Measure + * Allows for drawing of features for measurements. + * + * Inherits from: + * - <OpenLayers.Control> + */ +OpenLayers.Control.Measure = OpenLayers.Class(OpenLayers.Control, { + + /** + * APIProperty: events + * {<OpenLayers.Events>} Events instance for listeners and triggering + * control specific events. + * + * Register a listener for a particular event with the following syntax: + * (code) + * control.events.register(type, obj, listener); + * (end) + * + * Supported event types (in addition to those from <OpenLayers.Control.events>): + * measure - Triggered when a measurement sketch is complete. Listeners + * will receive an event with measure, units, order, and geometry + * properties. + * measurepartial - Triggered when a new point is added to the + * measurement sketch or if the <immediate> property is true and the + * measurement sketch is modified. Listeners receive an event with measure, + * units, order, and geometry. + */ + + /** + * APIProperty: handlerOptions + * {Object} Used to set non-default properties on the control's handler + */ + + /** + * Property: callbacks + * {Object} The functions that are sent to the handler for callback + */ + callbacks: null, + + /** + * APIProperty: displaySystem + * {String} Display system for output measurements. Supported values + * are 'english', 'metric', and 'geographic'. Default is 'metric'. + */ + displaySystem: 'metric', + + /** + * APIProperty: geodesic + * {Boolean} Calculate geodesic metrics instead of planar metrics. This + * requires that geometries can be transformed into Geographic/WGS84 + * (if that is not already the map projection). Default is false. + */ + geodesic: false, + + /** + * Property: displaySystemUnits + * {Object} Units for various measurement systems. Values are arrays + * of unit abbreviations (from OpenLayers.INCHES_PER_UNIT) in decreasing + * order of length. + */ + displaySystemUnits: { + geographic: ['dd'], + english: ['mi', 'ft', 'in'], + metric: ['km', 'm'] + }, + + /** + * Property: delay + * {Number} Number of milliseconds between clicks before the event is + * considered a double-click. The "measurepartial" event will not + * be triggered if the sketch is completed within this time. This + * is required for IE where creating a browser reflow (if a listener + * is modifying the DOM by displaying the measurement values) messes + * with the dblclick listener in the sketch handler. + */ + partialDelay: 300, + + /** + * Property: delayedTrigger + * {Number} Timeout id of trigger for measurepartial. + */ + delayedTrigger: null, + + /** + * APIProperty: persist + * {Boolean} Keep the temporary measurement sketch drawn after the + * measurement is complete. The geometry will persist until a new + * measurement is started, the control is deactivated, or <cancel> is + * called. + */ + persist: false, + + /** + * APIProperty: immediate + * {Boolean} Activates the immediate measurement so that the "measurepartial" + * event is also fired once the measurement sketch is modified. + * Default is false. + */ + immediate : false, + + /** + * Constructor: OpenLayers.Control.Measure + * + * Parameters: + * handler - {<OpenLayers.Handler>} + * options - {Object} + */ + initialize: function(handler, options) { + OpenLayers.Control.prototype.initialize.apply(this, [options]); + var callbacks = {done: this.measureComplete, + point: this.measurePartial}; + if (this.immediate){ + callbacks.modify = this.measureImmediate; + } + this.callbacks = OpenLayers.Util.extend(callbacks, this.callbacks); + + // let the handler options override, so old code that passes 'persist' + // directly to the handler does not need an update + this.handlerOptions = OpenLayers.Util.extend( + {persist: this.persist}, this.handlerOptions + ); + this.handler = new handler(this, this.callbacks, this.handlerOptions); + }, + + /** + * APIMethod: deactivate + */ + deactivate: function() { + this.cancelDelay(); + return OpenLayers.Control.prototype.deactivate.apply(this, arguments); + }, + + /** + * APIMethod: cancel + * Stop the control from measuring. If <persist> is true, the temporary + * sketch will be erased. + */ + cancel: function() { + this.cancelDelay(); + this.handler.cancel(); + }, + + /** + * APIMethod: setImmediate + * Sets the <immediate> property. Changes the activity of immediate + * measurement. + */ + setImmediate: function(immediate) { + this.immediate = immediate; + if (this.immediate){ + this.callbacks.modify = this.measureImmediate; + } else { + delete this.callbacks.modify; + } + }, + + /** + * Method: updateHandler + * + * Parameters: + * handler - {Function} One of the sketch handler constructors. + * options - {Object} Options for the handler. + */ + updateHandler: function(handler, options) { + var active = this.active; + if(active) { + this.deactivate(); + } + this.handler = new handler(this, this.callbacks, options); + if(active) { + this.activate(); + } + }, + + /** + * Method: measureComplete + * Called when the measurement sketch is done. + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + */ + measureComplete: function(geometry) { + this.cancelDelay(); + this.measure(geometry, "measure"); + }, + + /** + * Method: measurePartial + * Called each time a new point is added to the measurement sketch. + * + * Parameters: + * point - {<OpenLayers.Geometry.Point>} The last point added. + * geometry - {<OpenLayers.Geometry>} The sketch geometry. + */ + measurePartial: function(point, geometry) { + this.cancelDelay(); + geometry = geometry.clone(); + // when we're wating for a dblclick, we have to trigger measurepartial + // after some delay to deal with reflow issues in IE + if (this.handler.freehandMode(this.handler.evt)) { + // no dblclick in freehand mode + this.measure(geometry, "measurepartial"); + } else { + this.delayedTrigger = window.setTimeout( + OpenLayers.Function.bind(function() { + this.delayedTrigger = null; + this.measure(geometry, "measurepartial"); + }, this), + this.partialDelay + ); + } + }, + + /** + * Method: measureImmediate + * Called each time the measurement sketch is modified. + * + * Parameters: + * point - {<OpenLayers.Geometry.Point>} The point at the mouse position. + * feature - {<OpenLayers.Feature.Vector>} The sketch feature. + * drawing - {Boolean} Indicates whether we're currently drawing. + */ + measureImmediate : function(point, feature, drawing) { + if (drawing && !this.handler.freehandMode(this.handler.evt)) { + this.cancelDelay(); + this.measure(feature.geometry, "measurepartial"); + } + }, + + /** + * Method: cancelDelay + * Cancels the delay measurement that measurePartial began. + */ + cancelDelay: function() { + if (this.delayedTrigger !== null) { + window.clearTimeout(this.delayedTrigger); + this.delayedTrigger = null; + } + }, + + /** + * Method: measure + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + * eventType - {String} + */ + measure: function(geometry, eventType) { + var stat, order; + if(geometry.CLASS_NAME.indexOf('LineString') > -1) { + stat = this.getBestLength(geometry); + order = 1; + } else { + stat = this.getBestArea(geometry); + order = 2; + } + this.events.triggerEvent(eventType, { + measure: stat[0], + units: stat[1], + order: order, + geometry: geometry + }); + }, + + /** + * Method: getBestArea + * Based on the <displaySystem> returns the area of a geometry. + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + * + * Returns: + * {Array([Float, String])} Returns a two item array containing the + * area and the units abbreviation. + */ + getBestArea: function(geometry) { + var units = this.displaySystemUnits[this.displaySystem]; + var unit, area; + for(var i=0, len=units.length; i<len; ++i) { + unit = units[i]; + area = this.getArea(geometry, unit); + if(area > 1) { + break; + } + } + return [area, unit]; + }, + + /** + * Method: getArea + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + * units - {String} Unit abbreviation + * + * Returns: + * {Float} The geometry area in the given units. + */ + getArea: function(geometry, units) { + var area, geomUnits; + if(this.geodesic) { + area = geometry.getGeodesicArea(this.map.getProjectionObject()); + geomUnits = "m"; + } else { + area = geometry.getArea(); + geomUnits = this.map.getUnits(); + } + var inPerDisplayUnit = OpenLayers.INCHES_PER_UNIT[units]; + if(inPerDisplayUnit) { + var inPerMapUnit = OpenLayers.INCHES_PER_UNIT[geomUnits]; + area *= Math.pow((inPerMapUnit / inPerDisplayUnit), 2); + } + return area; + }, + + /** + * Method: getBestLength + * Based on the <displaySystem> returns the length of a geometry. + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + * + * Returns: + * {Array([Float, String])} Returns a two item array containing the + * length and the units abbreviation. + */ + getBestLength: function(geometry) { + var units = this.displaySystemUnits[this.displaySystem]; + var unit, length; + for(var i=0, len=units.length; i<len; ++i) { + unit = units[i]; + length = this.getLength(geometry, unit); + if(length > 1) { + break; + } + } + return [length, unit]; + }, + + /** + * Method: getLength + * + * Parameters: + * geometry - {<OpenLayers.Geometry>} + * units - {String} Unit abbreviation + * + * Returns: + * {Float} The geometry length in the given units. + */ + getLength: function(geometry, units) { + var length, geomUnits; + if(this.geodesic) { + length = geometry.getGeodesicLength(this.map.getProjectionObject()); + geomUnits = "m"; + } else { + length = geometry.getLength(); + geomUnits = this.map.getUnits(); + } + var inPerDisplayUnit = OpenLayers.INCHES_PER_UNIT[units]; + if(inPerDisplayUnit) { + var inPerMapUnit = OpenLayers.INCHES_PER_UNIT[geomUnits]; + length *= (inPerMapUnit / inPerDisplayUnit); + } + return length; + }, + + CLASS_NAME: "OpenLayers.Control.Measure" +}); |