Radius while drawing circle

lib/Styler/widgets/CircleSegment.js

@@ -0,0 +1,170 @@
+/**
+ * @requires OpenLayers/Handler/Path.js
+ */
+
+/**
+ * Class: OpenLayers.Handler.CircleSegment
+ * Handler to draw a circle while displaying the radius. 
+ *
+ * Inherits from:
+ *  - <OpenLayers.Handler.Path>
+ */
+OpenLayers.Handler.CircleSegment = OpenLayers.Class(OpenLayers.Handler.Path, {
+
+    /**
+     * Property: origin
+     * {<OpenLayers.Feature.Vector>} The origin of the segment, first clicked
+     *     point
+     */
+    origin: null,
+
+    /**
+     * Property: circle
+     * {<OpenLayers.Feature.Vector>} The drawn circle
+     */
+    circle: null,
+
+    /**
+     * Property: _drawing
+     * {Boolean} Indicates if in the process of drawing a segment.
+     *    (We prefix the variable name with an underscore not to
+     *     collide with a "drawing" property of the parent.)
+     */
+    _drawing: false,
+
+    /**
+     * Constructor: OpenLayers.Handler.CircleSegment 
+     */
+    initialize: function(control, callbacks, options) {
+        options = options || {};
+        options.maxVertices = 2;
+        options.persist = true;
+        options.freehandToggle = null;
+        OpenLayers.Handler.Path.prototype.initialize.apply(
+            this, [control, callbacks, options]);
+    },
+
+    /**
+     *
+     */
+    addPoint: function() {
+        OpenLayers.Handler.Path.prototype.addPoint.apply(this, arguments);
+        if (this.line.geometry.components.length == 2) {
+            var feature = this.origin = new OpenLayers.Feature.Vector(
+                this.line.geometry.components[0].clone());
+            this.layer.addFeatures([feature], {silent: true});
+            this._drawing = true;
+        }
+    },
+
+    /**
+     *
+     */
+    destroyPersistedFeature: function() {
+        OpenLayers.Handler.Path.prototype.destroyPersistedFeature.apply(
+            this, arguments);
+        if (this.layer) {
+            if (this.origin) {
+                this.origin.destroy();
+                this.origin = null;
+            }
+            if (this.circle) {
+                this.circle.destroy();
+                this.circle = null;
+            }
+        }
+    },
+
+    /**
+     *
+     */
+    modifyFeature: function() {
+        OpenLayers.Handler.Path.prototype.modifyFeature.apply(this, arguments);
+
+        if (this._drawing) {
+            if (this.circle) {
+                this.layer.removeFeatures([this.circle, this.point]);
+            }
+            var geometry = OpenLayers.Geometry.Polygon.createRegularPolygon(
+                this.origin.geometry, this.line.geometry.getLength(), 40
+            );
+
+            this.circle = new OpenLayers.Feature.Vector(geometry);
+            if (!this.point.style){
+                var style = OpenLayers.Util.applyDefaults(
+                        this.defaultStyle, OpenLayers.Feature.Vector.style["default"]);
+                this.point.style = style;
+            }
+
+            /** Display the radius **/
+            var curLength = this.line.geometry.getLength();
+            var label="";
+            if (curLength>1000) {
+                label = Math.round(curLength / 10) / 100 + " km ";
+            } else {
+                label = Math.round(curLength) + " m ";
+            }
+            this.layer.addFeatures([this.point], {silent: true});
+            this.point.style.label = label;
+            this.point.style.graphic = false;
+            this.point.style.labelSelect = true;
+
+            var o = this.origin.geometry,
+                p = this.point.geometry,
+                align,
+                xOffset,
+                yOffset;
+            if (o.x < p.x) {
+                align = 'l';
+                xOffset = 10;
+            } else {
+                align = 'r';
+                xOffset = -10;
+            }
+
+            if (o.y < p.y) {
+                align += 'b';
+                yOffset = 10;
+            } else {
+                align += 't';
+                yOffset = -10;
+            }
+            this.point.style.labelAlign = align;
+            this.point.style.labelXOffset = xOffset;
+            this.point.style.labelYOffset = yOffset;
+
+            this.layer.addFeatures([this.circle], {silent: true});
+        }
+    },
+
+    /**
+     *
+     */
+    deactivate: function() {
+        if (OpenLayers.Handler.Path.prototype.deactivate.call(this)) {
+            this._drawing = false;
+            return true;
+        }
+        return false;
+    },
+
+    /**
+     *
+     */
+    dblclick: function() {
+        // we don't want double click
+    },
+
+    finalize: function(cancel) {
+        var key = cancel ? "cancel" : "done";
+        this.mouseDown = false;
+        this.lastDown = null;
+        this.lastUp = null;
+        this.lastTouchPx = null;
+
+        if (this.circle && this.circle.geometry) {
+            this.callback(key, [this.circle.geometry.clone()]);
+        }
+        this.destroyFeature(cancel);
+    }
+});