Ticket #1241: measure.2.patch

lib/OpenLayers/Control/Measure.js

@@ +1 @@
+/* Copyright (c) 2006-2008 MetaCarta, Inc., 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/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, {
+
+    /**
+     * 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>):
+     *  - *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.  Listeners receive an event with measure,
+     *      units, order, and geometry.
+     */
+    EVENT_TYPES: ['measure', 'measurepartial'],
+
+    /**
+     * APIProperty: handlerOptions
+     * {Object} Used to set non-default properties on the control's handler
+     */
+    handlerOptions: null,
+    
+    /**
+     * Property: callbacks
+     * {Object} The functions that are sent to the handler for callback
+     */
+    callbacks: null,
+    
+    /**
+     * Property: displaySystem
+     * {String} Display system for output measurements.  Supported values
+     *     are 'english', 'metric', and 'geographic'.  Default is 'metric'.
+     */
+    displaySystem: 'metric',
+    
+    /**
+     * 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']
+    },
+
+    /**
+     * Constructor: OpenLayers.Control.Measure
+     * 
+     * Parameters:
+     * handler - {<OpenLayers.Handler>} 
+     * options - {Object} 
+     */
+    initialize: function(handler, options) {
+        // concatenate events specific to measure with those from the base
+        this.EVENT_TYPES =
+            OpenLayers.Control.Measure.prototype.EVENT_TYPES.concat(
+            OpenLayers.Control.prototype.EVENT_TYPES
+        );
+        OpenLayers.Control.prototype.initialize.apply(this, [options]);
+        this.callbacks = OpenLayers.Util.extend(
+            {done: this.measureComplete, point: this.measurePartial},
+            this.callbacks
+        );
+        this.handler = new handler(this, this.callbacks, this.handlerOptions);
+    },
+    
+    /**
+     * 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.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.measure(geometry, "measurepartial");
+    },
+
+    /**
+     * 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 = geometry.getArea();
+        var inPerDisplayUnit = OpenLayers.INCHES_PER_UNIT[units];
+        if(inPerDisplayUnit) {
+            var inPerMapUnit = OpenLayers.INCHES_PER_UNIT[this.map.getUnits()];
+            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 = geometry.getLength();
+        var inPerDisplayUnit = OpenLayers.INCHES_PER_UNIT[units];
+        if(inPerDisplayUnit) {
+            var inPerMapUnit = OpenLayers.INCHES_PER_UNIT[this.map.getUnits()];
+            length *= (inPerMapUnit / inPerDisplayUnit);
+        }
+        return length;
+    },
+
+    CLASS_NAME: "OpenLayers.Control.Measure"
+});

lib/OpenLayers.js

@@ -160 +160 @@
-            "OpenLayers/Control/DrawFeature.js",
-            "OpenLayers/Control/DragFeature.js",
-            "OpenLayers/Control/ModifyFeature.js",
+            "OpenLayers/Control/Measure.js",
-            "OpenLayers/Control/Panel.js",
-            "OpenLayers/Control/SelectFeature.js",
-            "OpenLayers/Control/NavigationHistory.js",