Commit beginning of item based mouse events. So far only onMousedown / 'mousedown' is supported.

src/core/Callback.js

@@ -32,7 +32,7 @@ var Callback = {
 			// See if this is the first handler that we're attaching, and 
 			// call install if defined.
 			if (entry.install && handlers.length == 1)
-				entry.install.call(this);
+				entry.install.call(this, type);
 		}
 		return this;
 	},
@@ -53,7 +53,7 @@ var Callback = {
 			if (!func || (index = handlers.indexOf(func)) != -1
 					&& handlers.length == 1) {
 				if (entry.uninstall)
-					entry.uninstall.call(this);
+					entry.uninstall.call(this, type);
 				delete this._handlers[type];
 			} else if (index != -1) {
 				// Just remove this one handler

src/item/Item.js

@@ -26,13 +26,58 @@
  */
 var Item = this.Item = Base.extend(Callback, /** @lends Item# */{
 	_events: new function() {
+
+		// Flags defining which native events are required by which Paper events
+		// as required for counting amount of necessary natives events.
+		// The mapping is native -> virtual
+		var mouseFlags = {
+			mousedown: {
+				mousedown: 1,
+				mousedrag: 1,
+				click: 1,
+				doubleclick: 1
+			},
+			mouseup: {
+				mouseup: 1,
+				mousedrag: 1,
+				click: 1,
+				doubleclick: 1
+			},
+			mousemove: {
+				mousedrag: 1,
+				mousemove: 1,
+				mouseenter: 1,
+				mouseleave: 1
+			}
+		};
+
+		// Entry for all mouse events in the _events list
+		var mouseEvent = {
+			install: function(type) {
+				var counters = this._project.view._eventCounters;
+				for (var key in mouseFlags) {
+					counters[key] = (counters[key] || 0)
+							+ (mouseFlags[key][type] || 0);
+				}
+			},
+			uninstall: function(type) {
+				var counters = this._project.view._eventCounters;
+				for (var key in mouseFlags)
+					counters[key] -= mouseFlags[key][type] || 0;
+			}
+		};
+
 		var onFrameItems = [];
 		function onFrame(event) {
 			for (var i = 0, l = onFrameItems.length; i < l; i++)
 				onFrameItems[i].fire('frame', event);
 		}
 
-		return {
+		return Base.each(['onMouseDown', 'onMouseUp', 'onMouseDrag', 'onClick',
+			'onDoubleClick', 'onMouseMove', 'onMouseEnter', 'onMouseLeave'],
+			function(name) {
+				this[name] = mouseEvent;
+			}, {
 				onFrame: {
 					install: function() {
 						if (!onFrameItems.length)
@@ -45,7 +90,7 @@ var Item = this.Item = Base.extend(Callback, /** @lends Item# */{
 							this._project.view.detach('frame', onFrame);
 					}
 				}
-		};
+			});
 	},
 
 	initialize: function() {

src/paper.js

@@ -114,6 +114,7 @@ var paper = new function() {
 /*#*/ include('ui/Event.js');
 /*#*/ include('ui/KeyEvent.js');
 /*#*/ include('ui/Key.js');
+/*#*/ include('ui/MouseEvent.js');
 
 /*#*/ include('tool/ToolEvent.js');
 /*#*/ include('tool/Tool.js');

src/ui/Event.js

@@ -25,15 +25,19 @@ var Event = this.Event = Base.extend(/** @lends Event# */{
 
 	// PORT: Add to Scriptographer
 	preventDefault: function() {
+		this._prevented = true;
 		DomEvent.preventDefault(this.event);
+		return this;
 	},
 
 	stopPropagation: function() {
+		this._stopped = true;
 		DomEvent.stopPropagation(this.event);
+		return this;
 	},
 
 	stop: function() {
-		DomEvent.stop(this.event);
+		return this.stopPropagation().preventDefault();
 	},
 
 	// DOCS: Document Event#modifiers

src/ui/MouseEvent.js

@@ -0,0 +1,42 @@
+/*
+ * Paper.js
+ *
+ * This file is part of Paper.js, a JavaScript Vector Graphics Library,
+ * based on Scriptographer.org and designed to be largely API compatible.
+ * http://paperjs.org/
+ * http://scriptographer.org/
+ *
+ * Copyright (c) 2011, Juerg Lehni & Jonathan Puckey
+ * http://lehni.org/ & http://jonathanpuckey.com/
+ *
+ * Distributed under the MIT license. See LICENSE file for details.
+ *
+ * All rights reserved.
+ */
+
+/**
+ * @name MouseEvent
+ *
+ * @extends Event
+ */
+var MouseEvent = this.MouseEvent = Event.extend(new function() {
+	return /** @lends MouseEvent# */{
+		initialize: function(type, point, target, event) {
+			this.base(event);
+			this.type = type;
+			this.point = point;
+			this.target = target;
+		},
+
+		/**
+		 * @return {String} A string representation of the key event.
+		 */
+		toString: function() {
+			return '{ type: ' + this.type
+					+ ', point: ' + this.point
+					+ ', target: ' + this.target
+					+ ', modifiers: ' + this.getModifiers()
+					+ ' }';
+		}
+	};
+});

src/ui/View.js

@@ -173,6 +173,7 @@ var View = this.View = Base.extend(Callback, /** @lends View# */{
 		this._context = this._canvas.getContext('2d');
 		this._matrix = new Matrix();
 		this._zoom = 1;
+		this._eventCounters = {};
 		// Make sure the first view is focused for keyboard input straight away
 		if (!View._focused)
 			View._focused = this;
@@ -553,6 +554,23 @@ var View = this.View = Base.extend(Callback, /** @lends View# */{
 		load: updateFocus
 	});
 
+	var hitOptions = {
+		fill: true,
+		stroke: true,
+		tolerance: 0
+	};
+
+	function callEvent(item, event, bubble) {
+		var called = false;
+		while (item) {
+			called = item.fire(event.type, event) || called;
+			if (called && (!bubble || event._stopped))
+				break;
+			item = item.getParent();
+		}
+		return called;
+	}
+
 	return {
 		_createHandlers: function() {
 			var view = this;
@@ -560,12 +578,25 @@ var View = this.View = Base.extend(Callback, /** @lends View# */{
 			function mousedown(event) {
 				// Tell the Key class which view should receive keyboard input.
 				View._focused = view;
-				if (!(tool = view._scope.tool))
-					return;
 				curPoint = viewToProject(view, event);
-				if (tool.onHandleEvent('mousedown', curPoint, event))
-					view.draw(true);
 				dragging = true;
+
+				var update = false;
+				// TODO: Move this to CanvasView soon!
+				if (view._eventCounters.mousedown) {
+					var hit = view._project.hitTest(curPoint, hitOptions);
+					if (hit && hit.item) {
+						update = callEvent(hit.item, new MouseEvent('mousedown',
+								curPoint, hit.item, event), false);
+					}
+				}
+
+				if (tool = view._scope.tool)
+					update = tool.onHandleEvent('mousedown', curPoint, event)
+							|| update;
+
+				if (update)
+					view.draw(true);
 			}
 
 			return {