* Added a new Workspace::GetPreviousWindow() method to allow traversing the window

list in the other direction.
* Since WorkspacesLayer now cuts out the current window from the clipping region,
  the window order was upside down; it now uses the new Workspace::GetPreviousWindow().
  This fixes bug #1105.
* WorkspacesLayer::MouseDown() now also uses GetPreviousWindow() which prevents it
  from needing to scan the whole window list for the top window at every click.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20382 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/Workspace.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2005-2006, Haiku.
+ * Copyright 2005-2007, Haiku.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -138,6 +138,28 @@ Workspace::GetNextWindow(WindowLayer*& _window, BPoint& _leftTop)
 }
 
 
+status_t
+Workspace::GetPreviousWindow(WindowLayer*& _window, BPoint& _leftTop)
+{
+	if (fCurrent == NULL)
+		fCurrent = fWorkspace.Windows().LastWindow();
+	else
+		fCurrent = fCurrent->PreviousWindow(fWorkspace.Index());
+
+	if (fCurrent == NULL)
+		return B_ENTRY_NOT_FOUND;
+
+	_window = fCurrent;
+
+	if (fCurrentWorkspace)
+		_leftTop = fCurrent->Frame().LeftTop();
+	else
+		_leftTop = fCurrent->Anchor(fWorkspace.Index()).position;
+
+	return B_OK;
+}
+
+
 void
 Workspace::RewindWindows()
 {

src/servers/app/Workspace.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2005, Haiku.
+ * Copyright 2005-2007, Haiku.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -28,6 +28,7 @@ class Workspace {
 						{ return fCurrentWorkspace; }
 
 		status_t	GetNextWindow(WindowLayer*& _window, BPoint& _leftTop);
+		status_t	GetPreviousWindow(WindowLayer*& _window, BPoint& _leftTop);
 		void		RewindWindows();
 
 		class Private;

src/servers/app/WorkspacesLayer.cpp

@@ -262,16 +262,16 @@ WorkspacesLayer::_DrawWorkspace(DrawingEngine* drawingEngine,
 	backgroundRegion.IntersectWith(&workspaceRegion);
 	drawingEngine->ConstrainClippingRegion(&backgroundRegion);
 
+	// We draw from top down and cut the window out of the clipping region
+	// which reduces the flickering
 	WindowLayer* window;
 	BPoint leftTop;
-	while (workspace.GetNextWindow(window, leftTop) == B_OK) {
+	while (workspace.GetPreviousWindow(window, leftTop) == B_OK) {
 		_DrawWindow(drawingEngine, rect, screenFrame, window,
 			leftTop, backgroundRegion, active);
 	}
 
 	// draw background
-
-	//drawingEngine->ConstrainClippingRegion(&backgroundRegion);
 	drawingEngine->FillRect(rect, color);
 
 	drawingEngine->ConstrainClippingRegion(&redraw);
@@ -376,15 +376,14 @@ WorkspacesLayer::MouseDown(BMessage* message, BPoint where)
 	WindowLayer* window;
 	BRect windowFrame;
 	BPoint leftTop;
-	while (workspace.GetNextWindow(window, leftTop) == B_OK) {
+	while (workspace.GetPreviousWindow(window, leftTop) == B_OK) {
 		BRect frame = _WindowFrame(workspaceFrame, screenFrame, window->Frame(),
 			leftTop);
 		if (frame.Contains(where) && window->Feel() != kDesktopWindowFeel
 			&& window->Feel() != kWindowScreenFeel) {
-			// We can't exit the loop here, as we traverse the window
-			// list in the wrong direction...
 			fSelectedWindow = window;
 			windowFrame = frame;
+			break;
 		}
 	}