From 7b8ff62e3ee75e19d9eeeabd31bedef371215554 Mon Sep 17 00:00:00 2001
From: jpbruyere <jp.bruyere@hotmail.com>
Date: Mon, 27 Apr 2015 14:58:27 +0200
Subject: [PATCH] Layouting queue

---
 GOLib.csproj                        |   8 ++
 Tests/GOLIBTest_1.1.cs              |  55 ++++++++++++
 Tests/GOLIBTest_1.2.cs              |  55 ++++++++++++
 Tests/Interfaces/test0.goml         |   4 +-
 Tests/Interfaces/test1.1.goml       |  15 ++++
 Tests/Interfaces/test1.2.goml       |  18 ++++
 Tests/Interfaces/test1.goml         |  15 ++--
 Tests/Tests.csproj                  |  20 ++++-
 src/GraphicObjects/Container.cs     |  60 ++++++-------
 src/GraphicObjects/GenericStack.cs  | 103 +++++----------------
 src/GraphicObjects/GraphicObject.cs | 135 ++++++++++++++--------------
 src/GraphicObjects/Group.cs         |  93 +++++++++----------
 src/GraphicObjects/ILayoutable.cs   |   9 +-
 src/GraphicObjects/Scroller.cs      |  28 +++---
 src/Interface.cs                    |   2 +
 src/LayoutingQueue.cs               |  40 +++++++++
 src/LayoutingQueueItem.cs           |  70 +++++++++++++++
 src/OpenTKGameWindow.cs             |  27 ++++--
 18 files changed, 490 insertions(+), 267 deletions(-)
 create mode 100644 Tests/GOLIBTest_1.1.cs
 create mode 100644 Tests/GOLIBTest_1.2.cs
 create mode 100755 Tests/Interfaces/test1.1.goml
 create mode 100755 Tests/Interfaces/test1.2.goml
 create mode 100644 src/LayoutingQueue.cs
 create mode 100644 src/LayoutingQueueItem.cs

diff --git a/GOLib.csproj b/GOLib.csproj
index 4aad6152..567b61c5 100644
--- a/GOLib.csproj
+++ b/GOLib.csproj
@@ -231,6 +231,14 @@
       <LogicalName>
       </LogicalName>
     </Compile>
+    <Compile Include="src\LayoutingQueueItem.cs">
+      <LogicalName>
+      </LogicalName>
+    </Compile>
+    <Compile Include="src\LayoutingQueue.cs">
+      <LogicalName>
+      </LogicalName>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <Reference Include="System" />
diff --git a/Tests/GOLIBTest_1.1.cs b/Tests/GOLIBTest_1.1.cs
new file mode 100644
index 00000000..b9cbdf65
--- /dev/null
+++ b/Tests/GOLIBTest_1.1.cs
@@ -0,0 +1,55 @@
+#define MONO_CAIRO_DEBUG_DISPOSE
+
+
+using System;
+using System.Runtime.InteropServices;
+using OpenTK;
+using OpenTK.Graphics.OpenGL;
+using OpenTK.Input;
+
+using System.Diagnostics;
+
+//using GGL;
+using go;
+using System.Threading;
+
+
+namespace test
+{
+	class GOLIBTest_1_1 : OpenTKGameWindow
+	{
+		public GOLIBTest_1_1 ()
+			: base(1024, 600,"test")
+		{}
+
+		Group g;
+
+		protected override void OnLoad (EventArgs e)
+		{
+			base.OnLoad (e);
+			LoadInterface("Interfaces/test1.1.goml", out g);
+
+		}
+		protected override void OnRenderFrame (FrameEventArgs e)
+		{
+			GL.Clear (ClearBufferMask.ColorBufferBit);
+			base.OnRenderFrame (e);
+			SwapBuffers ();
+		}
+
+		protected override void OnUpdateFrame (FrameEventArgs e)
+		{
+			base.OnUpdateFrame (e);
+		}
+
+		[STAThread]
+		static void Main ()
+		{
+			Console.WriteLine ("starting example");
+
+			using (GOLIBTest_1_1 win = new GOLIBTest_1_1( )) {
+				win.Run (30.0);
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/Tests/GOLIBTest_1.2.cs b/Tests/GOLIBTest_1.2.cs
new file mode 100644
index 00000000..629b2995
--- /dev/null
+++ b/Tests/GOLIBTest_1.2.cs
@@ -0,0 +1,55 @@
+#define MONO_CAIRO_DEBUG_DISPOSE
+
+
+using System;
+using System.Runtime.InteropServices;
+using OpenTK;
+using OpenTK.Graphics.OpenGL;
+using OpenTK.Input;
+
+using System.Diagnostics;
+
+//using GGL;
+using go;
+using System.Threading;
+
+
+namespace test
+{
+	class GOLIBTest_1_2 : OpenTKGameWindow
+	{
+		public GOLIBTest_1_2 ()
+			: base(1024, 600,"test")
+		{}
+
+		VerticalStack g;
+
+		protected override void OnLoad (EventArgs e)
+		{
+			base.OnLoad (e);
+			LoadInterface("Interfaces/test1.2.goml", out g);
+
+		}
+		protected override void OnRenderFrame (FrameEventArgs e)
+		{
+			GL.Clear (ClearBufferMask.ColorBufferBit);
+			base.OnRenderFrame (e);
+			SwapBuffers ();
+		}
+
+		protected override void OnUpdateFrame (FrameEventArgs e)
+		{
+			base.OnUpdateFrame (e);
+		}
+
+		[STAThread]
+		static void Main ()
+		{
+			Console.WriteLine ("starting example");
+
+			using (GOLIBTest_1_2 win = new GOLIBTest_1_2( )) {
+				win.Run (30.0);
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/Tests/Interfaces/test0.goml b/Tests/Interfaces/test0.goml
index 3163cc9a..102c1cac 100755
--- a/Tests/Interfaces/test0.goml
+++ b/Tests/Interfaces/test0.goml
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
 <GraphicObject 
-			Top="10" Left="10"
-			Width="10" Height="50" 
+			HorizontalAlignment="Right"
+			VerticalAlignment="Bottom"
 			Margin="10" Background="Green"/>
diff --git a/Tests/Interfaces/test1.1.goml b/Tests/Interfaces/test1.1.goml
new file mode 100755
index 00000000..6ccf2c1c
--- /dev/null
+++ b/Tests/Interfaces/test1.1.goml
@@ -0,0 +1,15 @@
+<?xml version="1.0"?>
+<Group Width="0" Height="0" Margin="50"
+	Focusable="True" Background="Yellow">
+	<Group Width="-1" Height="-1" Margin="50" 
+		VerticalAlignment="Top" HorizontalAlignment="Left"
+		Focusable="True" Background="Green">
+		<Image VerticalAlignment="Bottom"			
+			Name="PhaseOverlay" Width="100" Height="100" Path="image/u.svg" Background="Red"/>
+		<Image Top="100"		
+			Name="PhaseOverlay" Width="100" Height="100" Path="image/u.svg" Background="Red"/>
+	</Group>
+	<Image Top="100"		
+		Name="PhaseOverlay" Width="100" Height="100" Path="image/u.svg" Background="Red"/>
+
+</Group>
\ No newline at end of file
diff --git a/Tests/Interfaces/test1.2.goml b/Tests/Interfaces/test1.2.goml
new file mode 100755
index 00000000..c41135c9
--- /dev/null
+++ b/Tests/Interfaces/test1.2.goml
@@ -0,0 +1,18 @@
+<?xml version="1.0"?>
+<VerticalStack>
+	<Label Text="label11"/>
+	<Label Text="label21"/>
+	<HorizontalStack Width="-1" Height="-1" Margin="50"
+		Focusable="True" Background="DarkBlue">
+		<Label Text="label12"/>
+		<Label Text="label22"/>
+		<Label Text="label32"/>
+		<Label Text="label42"/>
+		<Label Text="label52"/>
+	</HorizontalStack>
+	<Label Text="label33" Background="Green" Width="0"/>
+	<Button/>
+	<Label Text="label43"/>
+	<Label Text="label53"/>
+
+</VerticalStack>
\ No newline at end of file
diff --git a/Tests/Interfaces/test1.goml b/Tests/Interfaces/test1.goml
index 43524e85..ff270768 100755
--- a/Tests/Interfaces/test1.goml
+++ b/Tests/Interfaces/test1.goml
@@ -1,9 +1,10 @@
 <?xml version="1.0"?>
-<Container
-	HorizontalAlignment="Left" VerticalAlignment="Center"
-	Margin="10" Focusable="True" Fit="True" Background="Green">
-	<Group   Background="White" >
-		<Image Name="PhaseOverlay" Width="40" Height="40"
-				Path="image/u.svg" Background="Red"/>
-	</Group>
+<Container Width="0" Height="-1"
+	Margin="100" Focusable="True" Background="Yellow">
+
+	<Container Width="-1" Height="-1"
+		Margin="10" Focusable="True" Background="Green">
+			<Image VerticalAlignment="Bottom"			
+				Name="PhaseOverlay" Width="100" Height="100" Path="image/u.svg" Background="Red"/>
+	</Container>
 </Container>
\ No newline at end of file
diff --git a/Tests/Tests.csproj b/Tests/Tests.csproj
index b65edb44..7d37271c 100644
--- a/Tests/Tests.csproj
+++ b/Tests/Tests.csproj
@@ -8,7 +8,7 @@
     <OutputType>Exe</OutputType>
     <RootNamespace>Tests</RootNamespace>
     <AssemblyName>Tests</AssemblyName>
-    <StartupObject>test.GOLIBTest_4</StartupObject>
+    <StartupObject>test.GOLIBTest_5</StartupObject>
     <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
     <OutputPath>..\bin\$(configuration)</OutputPath>
     <IntermediateOutputPath>obj\$(configuration)</IntermediateOutputPath>
@@ -64,6 +64,14 @@
       <LogicalName>
       </LogicalName>
     </Compile>
+    <Compile Include="GOLIBTest_1.1.cs">
+      <LogicalName>
+      </LogicalName>
+    </Compile>
+    <Compile Include="GOLIBTest_1.2.cs">
+      <LogicalName>
+      </LogicalName>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <None Include="image\u.svg">
@@ -101,6 +109,16 @@
       <LogicalName>
       </LogicalName>
     </None>
+    <None Include="Interfaces\test1.1.goml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <LogicalName>
+      </LogicalName>
+    </None>
+    <None Include="Interfaces\test1.2.goml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <LogicalName>
+      </LogicalName>
+    </None>
   </ItemGroup>
   <ItemGroup>
     <Folder Include="Interfaces\">
diff --git a/src/GraphicObjects/Container.cs b/src/GraphicObjects/Container.cs
index c1134ec5..1971f00b 100644
--- a/src/GraphicObjects/Container.cs
+++ b/src/GraphicObjects/Container.cs
@@ -77,41 +77,37 @@ namespace go
                 child.InvalidateLayout();
         }
 		protected override Size measureRawSize ()
+		{			
+			return child == null ? Bounds.Size : new Size(child.Slot.Width + 2 * (Margin),child.Slot.Height + 2 * (Margin));
+		}
+		public override void RegisterForLayouting ()
 		{
-			Size raw = Bounds.Size;
-
-			if (child != null) {
-				if (Bounds.Width < 0 && child.WIsValid)
-					raw.Width = child.Slot.Width + 2 * (Margin);
-				if (Bounds.Height < 0 && child.HIsValid)
-					raw.Height = child.Slot.Height + 2 * (Margin);
-			}
+			base.RegisterForLayouting ();
 
-			return raw;
+			if (child != null)
+				child.RegisterForLayouting ();
 		}
-        public override void UpdateLayout()
-        {
-			if (LayoutIsValid)
-                return;
-
-			if (Width < 0 && child.Width == 0)
-				child.Width = -1;
-			if (Height < 0 && child.Height == 0)
-				child.Height = -1;
-
-			if (!(base.LayoutIsValid))
-				base.UpdateLayout();
-				
-            if (child != null)
-            {
-				if (!child.LayoutIsValid) {
-					child.UpdateLayout ();
-				}
-            }
-
-            if (LayoutIsValid)
-                registerForRedraw();
-        }
+//		public override void UpdateLayout (LayoutingType layoutType)
+//        {
+//
+////			if (Width < 0 && child.Width == 0)
+////				child.Width = -1;
+////			if (Height < 0 && child.Height == 0)
+////				child.Height = -1;
+////
+////			if (!(base.LayoutIsValid))
+////				base.UpdateLayout();
+////				
+////            if (child != null)
+////            {
+////				if (!child.LayoutIsValid) {
+////					child.UpdateLayout ();
+////				}
+////            }
+////
+////            if (LayoutIsValid)
+////                registerForRedraw();
+//        }
 		public override Rectangle ContextCoordinates (Rectangle r)
 		{
 			return
diff --git a/src/GraphicObjects/GenericStack.cs b/src/GraphicObjects/GenericStack.cs
index a36cd7b1..36d41f99 100644
--- a/src/GraphicObjects/GenericStack.cs
+++ b/src/GraphicObjects/GenericStack.cs
@@ -18,7 +18,6 @@ namespace go
 		#endregion
 
 		#region Private fields
-		bool childrenArePositionned = false;
         int _spacing;
         Orientation _orientation;
 		#endregion
@@ -49,49 +48,25 @@ namespace go
 			get { return base.Height; }
 			set { base.Height = value; }
 		}
-		[XmlIgnore]public override bool LayoutIsValid {
-			get { return childrenArePositionned && base.LayoutIsValid; }
-			set { base.LayoutIsValid = value; }
-		}
 
-		public override void InvalidateLayout ()
-		{
-			childrenArePositionned = false;
-			base.InvalidateLayout ();
-		}
 		protected override Size measureRawSize ()
 		{
-			Size raw = Bounds.Size;
 			Size tmp = new Size ();
 
-			if (raw.Width >= 0 && raw.Height >= 0)
-				return raw;
-				
-			foreach (GraphicObject c in Children) {
-				if (raw.Width < 0) {
-					if (c.WIsValid) {
-						if (Orientation == Orientation.Horizontal && c.Bounds.Width != 0)
-							tmp.Width += c.Slot.Width + Spacing;
-						else
-							tmp.Width = Math.Max (tmp.Width, c.Slot.Right);
-					}else
-						return raw;
+			if (Orientation == Orientation.Horizontal) {
+				foreach (GraphicObject c in Children) {
+					tmp.Width += c.Slot.Width + Spacing;
+					tmp.Height = Math.Max (tmp.Height, c.Slot.Bottom);
 				}
-				if (raw.Height < 0) {
-					if (c.HIsValid) {
-						if (Orientation == Orientation.Vertical && c.Bounds.Height != 0)
-							tmp.Height += c.Slot.Height + Spacing;
-						else
-							tmp.Height = Math.Max (tmp.Height, c.Slot.Bottom);
-					}else
-						return raw;
+			} else {
+				foreach (GraphicObject c in Children) {
+					tmp.Width = Math.Max (tmp.Width, c.Slot.Right);
+					tmp.Height += c.Slot.Height + Spacing;
 				}
 			}
 
-			if (raw.Width < 0)
-				tmp.Width += 2*Margin;
-			if (raw.Height < 0)
-				tmp.Height += 2*Margin;
+			tmp.Width += 2*Margin;
+			tmp.Height += 2*Margin;
 
 			return tmp;
 		}
@@ -100,66 +75,36 @@ namespace go
 			int d = 0;
 			if (Orientation == Orientation.Horizontal) {
 				foreach (GraphicObject c in Children) {
-					if (c.Bounds.Width == 0)
-						continue;
-
 					c.Slot.X = d;
-					c.XIsValid = true;
 					d += c.Slot.Width + Spacing;
 				}
 			} else {
 				foreach (GraphicObject c in Children) {
-					if (c.Bounds.Height == 0)
-						continue;
-
 					c.Slot.Y = d;
-					c.YIsValid = true;
 					d += c.Slot.Height + Spacing;
 				}
 			}
-			childrenArePositionned = true;
 		}
+		public override void RegisterForLayouting ()
+		{
+			base.RegisterForLayouting ();
 
-        public override void UpdateLayout()
+			int idx = Interface.LayoutingQueue.IndexOf (Interface.LayoutingQueue.Where (lq => lq.GraphicObject.Parent == this).LastOrDefault ());
+			if (idx < 0)
+				return;
+			Interface.LayoutingQueue.Insert (
+				idx+1,
+				new LayoutingQueueItem (LayoutingType.PositionChildren, this));
+		}
+		public override void UpdateLayout (LayoutingType layoutType)
         {            
-            base.UpdateLayout();
-
-			ComputeChildrenPositions ();
+			if (layoutType == LayoutingType.PositionChildren)
+				ComputeChildrenPositions ();
 
-            if (LayoutIsValid)
-                registerForRedraw();
+			base.UpdateLayout(layoutType);
         }
 		#endregion
 
-		//
-//        bool enoughtSpaceForWidget(GraphicObject w)
-//        {
-//            if (!SizeToContent)
-//            {
-//                int nextXForWidget = 0;
-//                int nextYForWidget = 0;
-//
-//                if (Orientation == Orientation.Horizontal)
-//                    nextXForWidget = currentXForWidget + w.Slot.Width;
-//                else
-//                    nextYForWidget = nextYForWidget + w.Slot.Height;
-//
-//
-//                if (nextXForWidget > ClientRectangle.Right )
-//                    return false;
-//                if (currentYForWidget > ClientRectangle.Bottom )
-//                    return false;
-//            }
-//            return true;
-//        }
-//        void advance(GraphicObject w)
-//        {
-//            if (Orientation == Orientation.Horizontal)
-//                currentXForWidget = currentXForWidget + WidgetSpacing + w.Slot.Width;
-//            else
-//                currentYForWidget = currentYForWidget + WidgetSpacing + w.Slot.Height;
-//
-//        }
     
 	}
 }
diff --git a/src/GraphicObjects/GraphicObject.cs b/src/GraphicObjects/GraphicObject.cs
index 3ffda14a..c6756db2 100755
--- a/src/GraphicObjects/GraphicObject.cs
+++ b/src/GraphicObjects/GraphicObject.cs
@@ -117,7 +117,7 @@ namespace go
 			}
 		}
 		[XmlIgnore]public virtual IGOLibHost TopContainer {
-			get { return Parent.TopContainer; }
+			get { return Parent == null ? null : Parent.TopContainer; }
 		}
 		public virtual void InvalidateLayout ()
 		{
@@ -373,7 +373,8 @@ namespace go
 		public virtual void registerForGraphicUpdate ()
 		{
 			bmp = null;
-			registerForRedraw ();
+			RegisterForLayouting ();
+			//registerForRedraw ();
 			//Interface.registerForGraphicUpdate(this);
 		}
 		/// <summary>
@@ -381,7 +382,7 @@ namespace go
 		/// </summary>
 		public virtual void registerForRedraw ()
 		{
-			if (LayoutIsValid && Visible)
+			if (Visible && TopContainer != null)
 				TopContainer.gobjsToRedraw.Add (this);
 		}
 		public virtual void registerClipRect()
@@ -392,50 +393,48 @@ namespace go
 		{
 			return Bounds.Size;
 		}
-
-		protected virtual void ComputeSize()
+		public virtual void RegisterForLayouting()
 		{
-			Size rawSize = measureRawSize ();
-
-			if (!wIsValid) {
-				wIsValid = true;
-				if (Width > 0)
-					Slot.Width = Width;
-				else if (Width < 0) {
-					if (rawSize.Width > 0)
-						Slot.Width = rawSize.Width;
-					else
-						wIsValid = false;
-				} else if (Parent.WIsValid)
-					Slot.Width = Parent.ClientRectangle.Width;
-				else
-					wIsValid = false;				
+			//clear previous layouting for item
+			Interface.LayoutingQueue.RemoveAll (lq => lq.GraphicObject == this);
+
+			if (Bounds.Width == 0) { //stretch in parent
+				int idxParentW = Interface.LayoutingQueue.IndexOf (Interface.LayoutingQueue.Where(lq => lq.GraphicObject == this.Parent && lq.LayoutType == LayoutingType.Width).FirstOrDefault());
+				if (idxParentW < 0)
+					Interface.LayoutingQueue.Insert (0, new LayoutingQueueItem (LayoutingType.Width, this));
+				else//insert after parent sizing
+					Interface.LayoutingQueue.Insert (idxParentW + 1, new LayoutingQueueItem (LayoutingType.Width, this));
+			} else {//fit ou fixed
+				Interface.LayoutingQueue.Insert (0, new LayoutingQueueItem (LayoutingType.Width, this));
+				//for x positionning, sizing of obj and parent have to be done
+				int idxParentW = Interface.LayoutingQueue.IndexOf (Interface.LayoutingQueue.Where(lq => lq.GraphicObject == this.Parent && lq.LayoutType == LayoutingType.Width).FirstOrDefault());
+				if (idxParentW < 0)
+					Interface.LayoutingQueue.Insert (1, new LayoutingQueueItem (LayoutingType.X, this));
+				else//insert after parent sizing
+					Interface.LayoutingQueue.Insert (idxParentW + 1, new LayoutingQueueItem (LayoutingType.X, this));
 			}
-
-			if (!hIsValid) {
-				hIsValid = true;
-				if (Height > 0)
-					Slot.Height = Height;
-				else if (Height < 0) {
-					if (rawSize.Height > 0)
-						Slot.Height = rawSize.Height;
-					else
-						hIsValid = false;
-				} else if (Parent.HIsValid)
-					Slot.Height = Parent.ClientRectangle.Height;
+			if (Bounds.Height == 0) { //stretch
+				int idxParentH = Interface.LayoutingQueue.IndexOf (Interface.LayoutingQueue.Where(lq => lq.GraphicObject == this.Parent && lq.LayoutType == LayoutingType.Height).FirstOrDefault());
+				if (idxParentH < 0)
+					Interface.LayoutingQueue.Insert (0, new LayoutingQueueItem (LayoutingType.Height, this));
 				else
-					hIsValid = false;				
+					Interface.LayoutingQueue.Insert (idxParentH + 1, new LayoutingQueueItem (LayoutingType.Height, this));
+			} else {
+				Interface.LayoutingQueue.Insert (0, new LayoutingQueueItem (LayoutingType.Height, this));
+				int idxParentH = Interface.LayoutingQueue.IndexOf (Interface.LayoutingQueue.Where(lq => lq.GraphicObject == this.Parent && lq.LayoutType == LayoutingType.Height).FirstOrDefault());
+				if (idxParentH < 0)
+					Interface.LayoutingQueue.Insert (1, new LayoutingQueueItem (LayoutingType.Y, this));
+				else//insert after parent sizing
+					Interface.LayoutingQueue.Insert (idxParentH + 1, new LayoutingQueueItem (LayoutingType.Y, this));
 			}
+
 		}
-		protected virtual void ComputePosition()
-		{
-			if (!xIsValid) {
-				xIsValid = true;
-				if (Width == 0)
-					Slot.X = 0;
-				else if (Left != 0)
-					Slot.X = Left;
-				else if (Parent.WIsValid && WIsValid) {
+
+		public virtual void UpdateLayout (LayoutingType layoutType)
+		{			
+			switch (layoutType) {
+			case LayoutingType.X:
+				if (Bounds.X == 0) {
 					switch (HorizontalAlignment) {
 					case HorizontalAlignment.Left:
 						Slot.X = 0;
@@ -447,17 +446,12 @@ namespace go
 						Slot.X = Parent.ClientRectangle.Width / 2 - Slot.Width / 2;
 						break;
 					}
-				} else// if (Parent.getBounds().Width>=0)
-					xIsValid = false;
-			}
-
-			if (!yIsValid) {
-				yIsValid = true;
-				if (Height== 0)
-					Slot.Y = 0;
-				else if (Top != 0)
-					Slot.Y = Top;
-				else if (Parent.HIsValid && HIsValid) {
+					break;
+				}
+				Slot.X = Bounds.X;
+				break;
+			case LayoutingType.Y:
+				if (Bounds.Y == 0) {
 					switch (VerticalAlignment) {
 					case VerticalAlignment.Top:
 						Slot.Y = 0;
@@ -469,19 +463,30 @@ namespace go
 						Slot.Y = Parent.ClientRectangle.Height / 2 - Slot.Height / 2;
 						break;
 					}
-				} else// if (Parent.getBounds().Height>=0)
-					yIsValid = false;
+					break;
+				}
+				Slot.Y = Bounds.Y;
+				break;
+			case LayoutingType.Width:				
+				if (Width > 0)
+					Slot.Width = Width;
+				else if (Width < 0)
+					Slot.Width = measureRawSize ().Width;
+				else
+					Slot.Width = Parent.ClientRectangle.Width;
+				break;
+			case LayoutingType.Height:
+				if (Height > 0)
+					Slot.Height = Height;
+				else if (Height < 0)
+					Slot.Height = measureRawSize ().Height;
+				else
+					Slot.Height = Parent.ClientRectangle.Height;
+				break;
 			}
-		}
-		public virtual void UpdateLayout ()
-		{
-			if (!SizeIsValid)
-				ComputeSize ();
-			if (!PositionIsValid)
-				ComputePosition ();				
-			if (LayoutIsValid)
-				registerForRedraw ();
-
+			//if no layouting remains in queue for item, registre for redraw
+			if (Interface.LayoutingQueue.Where (lq => lq.GraphicObject == this).Count() <= 0)
+				this.registerForRedraw ();
 		}
 		protected virtual void onDraw(Context gr)
 		{
diff --git a/src/GraphicObjects/Group.cs b/src/GraphicObjects/Group.cs
index d2c48904..8056f06f 100644
--- a/src/GraphicObjects/Group.cs
+++ b/src/GraphicObjects/Group.cs
@@ -132,67 +132,58 @@ namespace go
 		}
 		protected override Size measureRawSize ()
 		{
-			Size raw = Bounds.Size;
 			Size tmp = new Size ();
 
-			if (raw.Width >= 0 && raw.Height >= 0)
-				return raw;
-
 			foreach (GraphicObject c in Children) {
-				if (raw.Width < 0) {
-					if (c.WIsValid)
-						tmp.Width = Math.Max (tmp.Width, c.Slot.Right);
-					else
-						return raw;
-				}
-				if (raw.Height < 0) {
-					if (c.HIsValid)
-						tmp.Height = Math.Max (tmp.Height, c.Slot.Bottom);
-					else
-						return raw;
-				}
+				tmp.Width = Math.Max (tmp.Width, c.Slot.Right);
+				tmp.Height = Math.Max (tmp.Height, c.Slot.Bottom);
 			}
 
-			if (raw.Width < 0)
-				tmp.Width += 2*Margin;
-			if (raw.Height < 0)
-				tmp.Height += 2*Margin;
+			tmp.Width += 2*Margin;
+			tmp.Height += 2*Margin;
 
 			return tmp;
 		}
-		public override void UpdateLayout()
+		public override void RegisterForLayouting ()
 		{
-			if (LayoutIsValid)
-				return;
-
-			bool atLeastOneChildHasWNotDependingOnParent = false;
-			bool atLeastOneChildHasHNotDependingOnParent = false;
-
-			foreach (GraphicObject c in Children) {
-				if (c.LayoutIsValid)
-					continue;
+			base.RegisterForLayouting ();
 
-				if (Width < 0 && c.WIsValid) {
-					if (!atLeastOneChildHasWNotDependingOnParent && !(this is GenericStack))
-						c.XIsValid = true;
-					atLeastOneChildHasWNotDependingOnParent = true;
-				}
-				if (Height < 0 && c.HIsValid) {
-					if (!atLeastOneChildHasHNotDependingOnParent && !(this is GenericStack))
-						c.YIsValid = true;
-					atLeastOneChildHasHNotDependingOnParent = true;
-				}
-
-				c.UpdateLayout ();
-			}
-
-//			if (Width < 0 && !atLeastOneChildHasWNotDependingOnParent)
-//				Debug.WriteLine ("ERROR: no child has fixed width and parent width is set to content!");
-//			if (Height < 0 && !atLeastOneChildHasHNotDependingOnParent)
-//				Debug.WriteLine ("ERROR: no child has fixed height and parent height is set to content!");
-
-			base.UpdateLayout ();
+			foreach (GraphicObject g in Children)
+				g.RegisterForLayouting ();			
 		}
+//		public override void UpdateLayout (LayoutingType layoutType)
+//		{
+//			if (LayoutIsValid)
+//				return;
+//
+//			bool atLeastOneChildHasWNotDependingOnParent = false;
+//			bool atLeastOneChildHasHNotDependingOnParent = false;
+//
+////			foreach (GraphicObject c in Children) {
+////				if (c.LayoutIsValid)
+////					continue;
+////
+////				if (Width < 0 && c.WIsValid) {
+////					if (!atLeastOneChildHasWNotDependingOnParent && !(this is GenericStack))
+////						c.XIsValid = true;
+////					atLeastOneChildHasWNotDependingOnParent = true;
+////				}
+////				if (Height < 0 && c.HIsValid) {
+////					if (!atLeastOneChildHasHNotDependingOnParent && !(this is GenericStack))
+////						c.YIsValid = true;
+////					atLeastOneChildHasHNotDependingOnParent = true;
+////				}
+////
+////				c.UpdateLayout ();
+////			}
+//
+////			if (Width < 0 && !atLeastOneChildHasWNotDependingOnParent)
+////				Debug.WriteLine ("ERROR: no child has fixed width and parent width is set to content!");
+////			if (Height < 0 && !atLeastOneChildHasHNotDependingOnParent)
+////				Debug.WriteLine ("ERROR: no child has fixed height and parent height is set to content!");
+//
+//			//base.UpdateLayout ();
+//		}
 
 		public override Rectangle ContextCoordinates(Rectangle r){
 			return r + ClientRectangle.Position;
@@ -212,7 +203,7 @@ namespace go
 
 		public override void Paint(ref Context ctx, Rectangles clip = null)
 		{
-			if ( !(Visible&LayoutIsValid) )
+			if ( !(Visible) )
 				return;
 
 			//			ctx.Save ();
diff --git a/src/GraphicObjects/ILayoutable.cs b/src/GraphicObjects/ILayoutable.cs
index 1107f825..088a4e83 100644
--- a/src/GraphicObjects/ILayoutable.cs
+++ b/src/GraphicObjects/ILayoutable.cs
@@ -6,14 +6,6 @@ namespace go
 	{
 		ILayoutable Parent { get; set; }
 
-		bool SizeIsValid { get; set; }
-		bool WIsValid { get; set; }
-		bool HIsValid { get; set; }
-		bool PositionIsValid { get; set; }
-		bool XIsValid { get; set; }
-		bool YIsValid { get; set; }
-		bool LayoutIsValid { get; set; }
-
 		Rectangle ClientRectangle { get; }
 		Rectangle getSlot();
 		Rectangle getBounds();
@@ -21,6 +13,7 @@ namespace go
 		IGOLibHost TopContainer { get; }
 
 		void InvalidateLayout ();
+		void UpdateLayout(LayoutingType layoutType);
 
 
 		Rectangle ContextCoordinates(Rectangle r);
diff --git a/src/GraphicObjects/Scroller.cs b/src/GraphicObjects/Scroller.cs
index 45a8a8b3..74e26c72 100644
--- a/src/GraphicObjects/Scroller.cs
+++ b/src/GraphicObjects/Scroller.cs
@@ -115,21 +115,21 @@ namespace go
 		{
 			TopContainer.redrawClip.AddRectangle (base.ScreenCoordinates(Slot));
 		}
-		public override void UpdateLayout ()
+		public override void UpdateLayout (LayoutingType layoutType)
 		{
-			base.UpdateLayout ();
-
-			if (!LayoutIsValid)
-				return;
-
-			//override child positionning inside scroller in the 
-			//scrolling direction
-			if (child == null)
-				return;
-			if (VerticalScrolling)
-				child.Slot.Y = 0;
-			if (HorizontalScrolling)
-				child.Slot.X = 0;
+//			base.UpdateLayout ();
+//
+//			if (!LayoutIsValid)
+//				return;
+//
+//			//override child positionning inside scroller in the 
+//			//scrolling direction
+//			if (child == null)
+//				return;
+//			if (VerticalScrolling)
+//				child.Slot.Y = 0;
+//			if (HorizontalScrolling)
+//				child.Slot.X = 0;
 		}
 		public override void Paint(ref Cairo.Context ctx, Rectangles clip = null)
 		{
diff --git a/src/Interface.cs b/src/Interface.cs
index 8f862381..8684d851 100644
--- a/src/Interface.cs
+++ b/src/Interface.cs
@@ -35,6 +35,8 @@ namespace go
 		public static bool ReplaceTabsWithSpace = false;
 		public static bool DesignerMode = false;
 
+		public static LayoutingQueue LayoutingQueue = new LayoutingQueue();
+
 		#region Load/Save
 
 		internal static List<EventSource> EventsToResolve;
diff --git a/src/LayoutingQueue.cs b/src/LayoutingQueue.cs
new file mode 100644
index 00000000..90152497
--- /dev/null
+++ b/src/LayoutingQueue.cs
@@ -0,0 +1,40 @@
+//
+//  LayoutingQueue.cs
+//
+//  Author:
+//       Jean-Philippe Bruyère <jp.bruyere@hotmail.com>
+//
+//  Copyright (c) 2015 jp
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+using System;
+using System.Collections.Generic;
+
+namespace go
+{
+	public class LayoutingQueue : List<LayoutingQueueItem>
+	{
+		public LayoutingQueue ()
+		{
+		}
+			
+		public LayoutingQueueItem Dequeue()
+		{
+			LayoutingQueueItem tmp = this [0];
+			this.RemoveAt (0);
+			return tmp;
+		}
+	}
+}
+
diff --git a/src/LayoutingQueueItem.cs b/src/LayoutingQueueItem.cs
new file mode 100644
index 00000000..4005f71e
--- /dev/null
+++ b/src/LayoutingQueueItem.cs
@@ -0,0 +1,70 @@
+//
+//  LayoutingQueueItem.cs
+//
+//  Author:
+//       Jean-Philippe Bruyère <jp.bruyere@hotmail.com>
+//
+//  Copyright (c) 2015 jp
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+using System;
+using System.Diagnostics;
+
+namespace go
+{
+	public enum LayoutingType
+	{
+		X,
+		Y,
+		Width,
+		Height,
+		PositionChildren
+	}
+
+	public class LayoutingQueueItem
+	{
+
+		public ILayoutable GraphicObject;
+		public LayoutingType LayoutType;
+
+		public LayoutingQueueItem (LayoutingType _layoutType, ILayoutable _graphicObject)
+		{
+			LayoutType = _layoutType;
+			GraphicObject = _graphicObject;
+		}
+		public void ProcessLayouting()
+		{
+			Debug.WriteLine ("Layouting => " + this.ToString ());
+			try {
+				GraphicObject.UpdateLayout (LayoutType);
+			} catch (Exception ex) {
+				Debug.WriteLine ("Layouting error: " + ex.ToString ());
+			}
+		}
+
+		public static implicit operator GraphicObject(LayoutingQueueItem queueItem)
+		{
+			return queueItem.GraphicObject as GraphicObject;
+		}
+		public static implicit operator LayoutingType(LayoutingQueueItem lqi)
+		{
+			return lqi.LayoutType;
+		}
+		public override string ToString ()
+		{
+			return string.Format ("{0}->{1}", LayoutType,GraphicObject.ToString());
+		}
+	}
+}
+
diff --git a/src/OpenTKGameWindow.cs b/src/OpenTKGameWindow.cs
index 644c65c8..2d491b20 100755
--- a/src/OpenTKGameWindow.cs
+++ b/src/OpenTKGameWindow.cs
@@ -78,6 +78,8 @@ namespace go
 		{
 			g.Parent = this;
 			GraphicObjects.Add (g);
+
+			g.RegisterForLayouting ();
 		}
 		public void DeleteWidget(GraphicObject g)
 		{
@@ -224,14 +226,18 @@ namespace go
 			GraphicObject[] invGOList = new GraphicObject[GraphicObjects.Count];
 			GraphicObjects.CopyTo (invGOList,0);
 			invGOList = invGOList.Reverse ().ToArray ();
-
-			foreach (GraphicObject p in invGOList) {
-				if (p.Visible) {
-					layoutTime.Start ();
-					while(!p.LayoutIsValid)
-						p.UpdateLayout ();
-					layoutTime.Stop ();
-				}
+//
+//			foreach (GraphicObject p in invGOList) {
+//				if (p.Visible) {
+//					layoutTime.Start ();
+//					while(!p.LayoutIsValid)
+//						p.UpdateLayout ();
+//					layoutTime.Stop ();
+//				}
+//			}
+			while (Interface.LayoutingQueue.Count > 0) {
+				LayoutingQueueItem lqi = Interface.LayoutingQueue.Dequeue ();
+				lqi.ProcessLayouting ();
 			}
 
 			//Debug.WriteLine ("otd:" + gobjsToRedraw.Count.ToString () + "-");
@@ -457,6 +463,11 @@ namespace go
 
 		#region ILayoutable implementation
 
+		public void UpdateLayout (LayoutingType layoutType)
+		{
+			throw new NotImplementedException ();
+		}
+
 		public Rectangle ContextCoordinates (Rectangle r)
 		{
 			return r;
-- 
2.47.3