Implement an optimization in _changed() notifications where not all curves need to updated if only segments change that already have told their curves about the change.

src/item/ChangeFlag.js

@@ -13,23 +13,26 @@
 var ChangeFlag = {
 	// Anything affecting the appearance of an item, including GEOMETRY,
 	// STROKE, STYLE and ATTRIBUTE (except for the invisible ones: locked, name)
-	APPEARANCE: 1,
+	APPEARANCE: 0x1,
 	// Change in item hierarchy
-	HIERARCHY: 2,
+	HIERARCHY: 0x2,
 	// Item geometry (path, bounds)
-	GEOMETRY: 4,
+	GEOMETRY: 0x4,
+	// Only segment(s) have changed, and affected curves have alredy been
+	// notified. This is to implement an optimization in _changed() calls.
+	SEGMENTS: 0x8,
 	// Stroke geometry (excluding color)
-	STROKE: 8,
+	STROKE: 0x10,
 	// Fill style or stroke color / dash
-	STYLE: 16,
+	STYLE: 0x20,
 	// Item attributes: visible, blendMode, locked, name, opacity, clipMask ...
-	ATTRIBUTE: 32,
+	ATTRIBUTE: 0x40,
 	// Text content
-	CONTENT: 64,
+	CONTENT: 0x80,
 	// Raster pixels
-	PIXELS: 128,
+	PIXELS: 0x100,
 	// Clipping in one of the child items
-	CLIPPING: 256
+	CLIPPING: 0x200
 };
 
 // Shortcuts to often used ChangeFlag values including APPEARANCE
@@ -39,6 +42,7 @@ var Change = {
 	HIERARCHY: ChangeFlag.HIERARCHY | ChangeFlag.GEOMETRY
 			| ChangeFlag.APPEARANCE,
 	GEOMETRY: ChangeFlag.GEOMETRY | ChangeFlag.APPEARANCE,
+	SEGMENTS: ChangeFlag.SEGMENTS | ChangeFlag.GEOMETRY | ChangeFlag.APPEARANCE,
 	STROKE: ChangeFlag.STROKE | ChangeFlag.STYLE | ChangeFlag.APPEARANCE,
 	STYLE: ChangeFlag.STYLE | ChangeFlag.APPEARANCE,
 	ATTRIBUTE: ChangeFlag.ATTRIBUTE | ChangeFlag.APPEARANCE,

src/path/Path.js

@@ -138,14 +138,19 @@ var Path = PathItem.extend(/** @lends Path# */{
 	_changed: function _changed(flags) {
 		_changed.base.call(this, flags);
 		if (flags & /*#=*/ ChangeFlag.GEOMETRY) {
-			// Clear cached native Path
-			(this._compound ? this._parent : this)._currentPath = undefined;
+			// Clear cached native Path. Clear on the parent too, for
+			// CompoundPaths and Groups (ab)used as clipping paths.
+			this._currentPath = undefined;
+			var parent = this._parent;
+			if (parent)
+				parent._currentPath = undefined;
 			// Clockwise state becomes undefined as soon as geometry changes.
 			this._length = this._clockwise = undefined;
-			// Curves are no longer valid
-			if (this._curves) {
+			// Only notify all curves if we're not told that only one Segment
+			// has changed and took already care of notifications.
+			if (this._curves && !(flags & /*#=*/ ChangeFlag.SEGMENTS)) {
 				for (var i = 0, l = this._curves.length; i < l; i++)
-					this._curves[i]._changed(/*#=*/ Change.GEOMETRY);
+					this._curves[i]._changed();
 			}
 			// Clear cached curves used for winding direction and containment
 			// calculation.
@@ -327,7 +332,7 @@ var Path = PathItem.extend(/** @lends Path# */{
 					this._curves[length - 1] = new Curve(this,
 						this._segments[length - 1], this._segments[0]);
 			}
-			this._changed(/*#=*/ Change.GEOMETRY);
+			this._changed(/*#=*/ Change.SEGMENTS);
 		}
 	},
 
@@ -414,7 +419,7 @@ var Path = PathItem.extend(/** @lends Path# */{
 			// Adjust segments for the curves before and after the removed ones
 			this._adjustCurves(from, to);
 		}
-		this._changed(/*#=*/ Change.GEOMETRY);
+		this._changed(/*#=*/ Change.SEGMENTS);
 		return segs;
 	},
 
@@ -738,7 +743,7 @@ var Path = PathItem.extend(/** @lends Path# */{
 			// Adjust segments for the curves before and after the removed ones
 			this._adjustCurves(index, index);
 		}
-		this._changed(/*#=*/ Change.GEOMETRY);
+		this._changed(/*#=*/ Change.SEGMENTS);
 		return removed;
 	},
 
@@ -1280,7 +1285,6 @@ var Path = PathItem.extend(/** @lends Path# */{
 				last1.remove();
 				this.setClosed(true);
 			}
-			this._changed(/*#=*/ Change.GEOMETRY);
 			return true;
 		}
 		return false;

src/path/Segment.js

@@ -170,7 +170,7 @@ var Segment = Base.extend(/** @lends Segment# */{
 					&& (curveOut = curves[index]))
 				curveOut._changed();
 		}
-		path._changed(/*#=*/ Change.GEOMETRY);
+		path._changed(/*#=*/ Change.SEGMENTS);
 	},
 
 	/**