From 8b991ecaaa5bfb6e682f73e426b136600d249f4e Mon Sep 17 00:00:00 2001
From: Robin Sedlaczek <robin.sedlaczek@live.de>
Date: Wed, 8 Oct 2014 18:02:02 +0200
Subject: [PATCH 1/3] Implement IHasObjectSpace for Teapot.

---
 .../Core/IHasObjectSpace.cs                   |  1 +
 .../Evaluators/Evaluator.cs                   |  1 +
 .../SharpGL.SceneGraph/Primitives/Teapot.cs   | 39 ++++++++++++++
 .../SharpGL.SceneGraph/Quadrics/Quadric.cs    |  1 +
 .../WPF/TeapotSample/MainWindow.xaml.cs       | 14 +----
 .../Tools/SceneBuilder/SceneBuilder.csproj    | 19 +++----
 .../Tools/SharpGLStudio/MainWindow.xaml.cs    | 15 +-----
 .../Tools/SharpGLStudio/SharpGLStudio.csproj  | 51 ++++++++++++-------
 8 files changed, 86 insertions(+), 55 deletions(-)

diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Core/IHasObjectSpace.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Core/IHasObjectSpace.cs
index 06848fa8..df36bdf4 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Core/IHasObjectSpace.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Core/IHasObjectSpace.cs
@@ -29,6 +29,7 @@ public interface IHasObjectSpace
         /// </summary>
         LinearTransformation Transformation
         {
+            set;
             get;
         }
     }
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Evaluators/Evaluator.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Evaluators/Evaluator.cs
index a555c4b9..8ca93428 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Evaluators/Evaluator.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Evaluators/Evaluator.cs
@@ -120,6 +120,7 @@ public bool DrawControlGrid
         [Description("The Quadric Object Space Transformation"), Category("Evaluator")]
         public LinearTransformation Transformation
         {
+            set { hasObjectSpaceHelper.Transformation = value; }
             get { return hasObjectSpaceHelper.Transformation; }
         }
 	}
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
index b96ef485..1f2dbf79 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
@@ -1,7 +1,10 @@
 using System;
+using System.ComponentModel;
 using System.Runtime.InteropServices;
 using SharpGL.SceneGraph.Core;
 using SharpGL.SceneGraph.Assets;
+using SharpGL.SceneGraph.Helpers;
+using SharpGL.SceneGraph.Transformations;
 
 namespace SharpGL.SceneGraph.Primitives
 {
@@ -10,9 +13,15 @@ namespace SharpGL.SceneGraph.Primitives
     /// </summary>
     public class Teapot : 
         SceneElement, 
+        IHasObjectSpace,
         IRenderable,
         IHasMaterial
     {
+        /// <summary>
+        /// The IHasObjectSpace helper.
+        /// </summary>
+        private HasObjectSpaceHelper hasObjectSpaceHelper = new HasObjectSpaceHelper();
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Teapot"/> class.
         /// </summary>
@@ -240,6 +249,36 @@ public Material Material
             get; 
             set; 
         }
+
+        /// <summary>
+        /// Pushes us into Object Space using the transformation into the specified OpenGL instance.
+        /// </summary>
+        /// <param name="gl">The OpenGL instance.</param>
+        public void PushObjectSpace(OpenGL gl)
+        {
+            //  Use the helper to push us into object space.
+            hasObjectSpaceHelper.PushObjectSpace(gl);
+        }
+
+        /// <summary>
+        /// Pops us from Object Space using the transformation into the specified OpenGL instance.
+        /// </summary>
+        /// <param name="gl">The gl.</param>
+        public void PopObjectSpace(OpenGL gl)
+        {
+            //  Use the helper to pop us from object space.
+            hasObjectSpaceHelper.PopObjectSpace(gl);
+        }
+
+        /// <summary>
+        /// Gets the transformation that pushes us into object space.
+        /// </summary>
+        [Description("The Teapot Object Space Transformation"), Category("Teapot")]
+        public LinearTransformation Transformation
+        {
+            get { return hasObjectSpaceHelper.Transformation; }
+            set { hasObjectSpaceHelper.Transformation = value; }
+        }
     }
 
     /// <summary>
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Quadric.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Quadric.cs
index 5cc42652..ba037424 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Quadric.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Quadric.cs
@@ -158,6 +158,7 @@ public bool TextureCoords
         [Description("The Quadric Object Space Transformation"), Category("Quadric")]
         public LinearTransformation Transformation
         {
+            set { hasObjectSpaceHelper.Transformation = value; }
             get { return hasObjectSpaceHelper.Transformation; }
         }
 
diff --git a/source/SharpGL/Samples/WPF/TeapotSample/MainWindow.xaml.cs b/source/SharpGL/Samples/WPF/TeapotSample/MainWindow.xaml.cs
index 923f5329..b5dccb0e 100644
--- a/source/SharpGL/Samples/WPF/TeapotSample/MainWindow.xaml.cs
+++ b/source/SharpGL/Samples/WPF/TeapotSample/MainWindow.xaml.cs
@@ -1,16 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Windows;
-using System.Windows.Controls;
-using System.Windows.Data;
-using System.Windows.Documents;
-using System.Windows.Input;
-using System.Windows.Media;
-using System.Windows.Media.Imaging;
-using System.Windows.Navigation;
-using System.Windows.Shapes;
+using System.Windows;
 using SharpGL;
 using SharpGL.SceneGraph.Primitives;
 using SharpGL.SceneGraph;
diff --git a/source/SharpGL/Tools/SceneBuilder/SceneBuilder.csproj b/source/SharpGL/Tools/SceneBuilder/SceneBuilder.csproj
index ea354122..20f23ca4 100644
--- a/source/SharpGL/Tools/SceneBuilder/SceneBuilder.csproj
+++ b/source/SharpGL/Tools/SceneBuilder/SceneBuilder.csproj
@@ -122,15 +122,6 @@
     <Reference Include="System.Xml">
       <Name>System.XML</Name>
     </Reference>
-    <ProjectReference Include="..\..\Core\SharpGL.WinForms\SharpGL.WinForms.csproj">
-      <Project>{B2984A6D-AD1C-4BE9-94AB-BA002B338751}</Project>
-      <Name>SharpGL.WinForms</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\Core\SharpGL\SharpGL.csproj">
-      <Name>SharpGL</Name>
-      <Project>{5EF45533-E2C7-46F2-B4A3-B8F36CD406E0}</Project>
-      <Package>{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</Package>
-    </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <Content Include="App.ico" />
@@ -199,6 +190,16 @@
   <ItemGroup>
     <None Include="app.config" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\Core\SharpGL.WinForms\SharpGL.WinForms.csproj">
+      <Project>{b2984a6d-ad1c-4be9-94ab-ba002b338751}</Project>
+      <Name>SharpGL.WinForms</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\..\Core\SharpGL\SharpGL.csproj">
+      <Project>{5ef45533-e2c7-46f2-b4a3-b8f36cd406e0}</Project>
+      <Name>SharpGL</Name>
+    </ProjectReference>
+  </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <PropertyGroup>
     <PreBuildEvent>
diff --git a/source/SharpGL/Tools/SharpGLStudio/MainWindow.xaml.cs b/source/SharpGL/Tools/SharpGLStudio/MainWindow.xaml.cs
index 48174f1c..7302e2e9 100644
--- a/source/SharpGL/Tools/SharpGLStudio/MainWindow.xaml.cs
+++ b/source/SharpGL/Tools/SharpGLStudio/MainWindow.xaml.cs
@@ -1,17 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Windows;
-using System.Windows.Controls;
-using System.Windows.Data;
-using System.Windows.Documents;
-using System.Windows.Input;
-using System.Windows.Media;
-using System.Windows.Media.Imaging;
-using System.Windows.Navigation;
-using System.Windows.Shapes;
-using Microsoft.Windows.Controls.Ribbon;
+using Microsoft.Windows.Controls.Ribbon;
 using Apex.MVVM;
 using Microsoft.Win32;
 using SharpGL.SceneGraph;
diff --git a/source/SharpGL/Tools/SharpGLStudio/SharpGLStudio.csproj b/source/SharpGL/Tools/SharpGLStudio/SharpGLStudio.csproj
index 9c686246..2ec493e5 100644
--- a/source/SharpGL/Tools/SharpGLStudio/SharpGLStudio.csproj
+++ b/source/SharpGL/Tools/SharpGLStudio/SharpGLStudio.csproj
@@ -24,6 +24,8 @@
     </SccAuxPath>
     <SccProvider>
     </SccProvider>
+    <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\..\</SolutionDir>
+    <RestorePackages>true</RestorePackages>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x86' ">
     <PlatformTarget>x86</PlatformTarget>
@@ -49,9 +51,13 @@
       <SpecificVersion>False</SpecificVersion>
       <HintPath>..\..\Dependencies\Apex.dll</HintPath>
     </Reference>
+    <Reference Include="Microsoft.Windows.Shell, Version=3.5.41019.1, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>C:\Program Files (x86)\Microsoft Ribbon for WPF\V3.5\Microsoft.Windows.Shell.dll</HintPath>
+    </Reference>
     <Reference Include="RibbonControlsLibrary, Version=4.0.0.11019, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\..\Dependencies\RibbonControlsLibrary.dll</HintPath>
+      <HintPath>C:\Program Files (x86)\Microsoft Ribbon for WPF\V3.5\RibbonControlsLibrary.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.Activities" />
@@ -142,24 +148,6 @@
   <ItemGroup>
     <Resource Include="Resources\BackgroundBrush.bmp" />
   </ItemGroup>
-  <ItemGroup>
-    <ProjectReference Include="..\..\Core\SharpGL.SceneGraph\SharpGL.SceneGraph.csproj">
-      <Project>{47BCAA39-EDAD-4404-B6BD-4742B0ABB523}</Project>
-      <Name>SharpGL.SceneGraph</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\Core\SharpGL.Serialization\SharpGL.Serialization.csproj">
-      <Project>{FDFA2632-A960-4778-A517-CA9E337C037C}</Project>
-      <Name>SharpGL.Serialization</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\Core\SharpGL.WPF\SharpGL.WPF.csproj">
-      <Project>{53E67055-13D2-4467-BB57-79589AFAC2CD}</Project>
-      <Name>SharpGL.WPF</Name>
-    </ProjectReference>
-    <ProjectReference Include="..\..\Core\SharpGL\SharpGL.csproj">
-      <Project>{5EF45533-E2C7-46F2-B4A3-B8F36CD406E0}</Project>
-      <Name>SharpGL</Name>
-    </ProjectReference>
-  </ItemGroup>
   <ItemGroup>
     <Resource Include="Images\AlignCenter_16x16.png" />
     <Resource Include="Images\AlignLeft_16x16.png" />
@@ -251,7 +239,32 @@
     <Resource Include="Images\UpArrow_16x16.png" />
     <Resource Include="Images\UpArrow_32x32.png" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\Core\SharpGL.SceneGraph\SharpGL.SceneGraph.csproj">
+      <Project>{47bcaa39-edad-4404-b6bd-4742b0abb523}</Project>
+      <Name>SharpGL.SceneGraph</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\..\Core\SharpGL.Serialization\SharpGL.Serialization.csproj">
+      <Project>{fdfa2632-a960-4778-a517-ca9e337c037c}</Project>
+      <Name>SharpGL.Serialization</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\..\Core\SharpGL.WPF\SharpGL.WPF.csproj">
+      <Project>{53e67055-13d2-4467-bb57-79589afac2cd}</Project>
+      <Name>SharpGL.WPF</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\..\Core\SharpGL\SharpGL.csproj">
+      <Project>{5ef45533-e2c7-46f2-b4a3-b8f36cd406e0}</Project>
+      <Name>SharpGL</Name>
+    </ProjectReference>
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <Import Project="$(SolutionDir)\.nuget\NuGet.targets" Condition="Exists('$(SolutionDir)\.nuget\NuGet.targets')" />
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('$(SolutionDir)\.nuget\NuGet.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(SolutionDir)\.nuget\NuGet.targets'))" />
+  </Target>
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">

From 5127fc7ff2a78c04265f84199d3182dc36c74bd3 Mon Sep 17 00:00:00 2001
From: Robin Sedlaczek <robin.sedlaczek@live.de>
Date: Fri, 10 Oct 2014 04:09:24 +0200
Subject: [PATCH 2/3] Adapt axies a little bit.

---
 .../Core/SharpGL.SceneGraph/Primitives/Axies.cs    | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Axies.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Axies.cs
index cd36814d..1fb277dc 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Axies.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Axies.cs
@@ -61,19 +61,19 @@ private void CreateDisplayList(OpenGL gl)
             gl.DepthFunc(OpenGL.GL_ALWAYS);
 
             //  Set a nice fat line width.
-            gl.LineWidth(1.50f);
+            gl.LineWidth(2.0f);
 
             //  Draw the axies.
             gl.Begin(OpenGL.GL_LINES);
-            gl.Color(1f, 0f, 0f, 1f);
+            gl.Color(0.75f, 0f, 0f, 0.5f);
             gl.Vertex(0, 0, 0);
-            gl.Vertex(3, 0, 0);
-            gl.Color(0f, 1f, 0f, 1f);
+            gl.Vertex(1.5, 0, 0);
+            gl.Color(0f, 0.75f, 0f, 0.5f);
             gl.Vertex(0, 0, 0);
-            gl.Vertex(0, 3, 0);
-            gl.Color(0f, 0f, 1f, 1f);
+            gl.Vertex(0, 1.5, 0);
+            gl.Color(0f, 0f, 0.75f, 0.5f);
             gl.Vertex(0, 0, 0);
-            gl.Vertex(0, 0, 3);
+            gl.Vertex(0, 0, 1.5);
             gl.End();
 
             //  Restore attributes.

From 918215e1ba9c329359901bcd283fbf576880aa7b Mon Sep 17 00:00:00 2001
From: Robin Sedlaczek <robin.sedlaczek@live.de>
Date: Thu, 23 Oct 2014 06:50:51 +0200
Subject: [PATCH 3/3] Implement bounding volumes for polygon and teapot. Move
 ArrayExtensions class to own file.

---
 .../Primitives/ArrayExtensions.cs             |  27 ++
 .../SharpGL.SceneGraph/Primitives/Cube.cs     |   5 +-
 .../SharpGL.SceneGraph/Primitives/Polygon.cs  |  55 ++--
 .../SharpGL.SceneGraph/Primitives/Teapot.cs   | 241 ++++++++----------
 .../Core/SharpGL.SceneGraph/Quadrics/Disk.cs  |  35 ++-
 .../SharpGL.SceneGraph.csproj                 |   1 +
 6 files changed, 214 insertions(+), 150 deletions(-)
 create mode 100644 source/SharpGL/Core/SharpGL.SceneGraph/Primitives/ArrayExtensions.cs

diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/ArrayExtensions.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/ArrayExtensions.cs
new file mode 100644
index 00000000..8ebb9e79
--- /dev/null
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/ArrayExtensions.cs
@@ -0,0 +1,27 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace SharpGL.SceneGraph.Primitives
+{
+    /// <summary>
+    /// Extensions for Array type.
+    /// </summary>
+    public static class ArrayExtensions
+    {
+        /// <summary>
+        /// Flattens the specified array.
+        /// </summary>
+        /// <typeparam name="T">The array type.</typeparam>
+        /// <param name="array">The array.</param>
+        /// <returns>The flattened array.</returns>
+        public static T[] Flatten<T>(this T[,,] array)
+            where T : struct
+        {
+            int size = Marshal.SizeOf(array[0, 0, 0]);
+            int totalSize = Buffer.ByteLength(array);
+            T[] result = new T[totalSize / size];
+            Buffer.BlockCopy(array, 0, result, 0, totalSize);
+            return result;
+        }
+    }
+}
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Cube.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Cube.cs
index 2d02fc01..35abf632 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Cube.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Cube.cs
@@ -87,6 +87,9 @@ private void CreateCubeGeometry()
 			face.Indices.Add(new Index(3, 2));
 			face.Indices.Add(new Index(2, 3));
             Faces.Add(face);
-		}
+
+            BoundingVolume.FromVertices(Vertices);
+            BoundingVolume.Pad(0.1f);
+        }
     }
 }
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Polygon.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Polygon.cs
index 91aedad7..30e3414a 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Polygon.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Polygon.cs
@@ -53,13 +53,13 @@ public virtual void AddFaceFromVertexData(Vertex[] vertexData)
 			foreach(Vertex v in vertexData)
 			{
 				//	Do we have this vertex already?
-				int at = VertexSearch.Search(vertices, 0, v, 0.01f);
+				int at = VertexSearch.Search(Vertices, 0, v, 0.01f);
 				
 				//	Add the vertex, and index it.
                 if (at == -1)
                 {
-                    newFace.Indices.Add(new Index(vertices.Count));
-                    vertices.Add(v);
+                    newFace.Indices.Add(new Index(Vertices.Count));
+                    Vertices.Add(v);
                 }
                 else
                 {
@@ -67,8 +67,11 @@ public virtual void AddFaceFromVertexData(Vertex[] vertexData)
                 }
 			}
 
-			//	Add the face.
-			faces.Add(newFace);
+            boundingVolumeHelper.BoundingVolume.FromVertices(vertices);
+            boundingVolumeHelper.BoundingVolume.Pad(0.1f);
+
+            //	Add the face.
+            faces.Add(newFace);
 		}
 
 		/// <summary>
@@ -163,7 +166,7 @@ public virtual void Render(OpenGL gl, RenderMode renderMode)
                     }
 
                     //	Set the vertex.
-                    gl.Vertex(vertices[index.Vertex]);
+                    gl.Vertex(Vertices[index.Vertex]);
                 }
 
                 gl.End();
@@ -191,7 +194,7 @@ public virtual void Render(OpenGL gl, RenderMode renderMode)
                         if (index.Normal != -1 && index.Vertex != -1)
                         {
                             //	Get the vertex.
-                            Vertex vertex = vertices[index.Vertex];
+                            Vertex vertex = Vertices[index.Vertex];
 
                             //	Get the normal vertex.
                             Vertex normal = normals[index.Normal];
@@ -279,7 +282,10 @@ public virtual bool CreateFromMap(string filename, int xPoints, int yPoints)
 				}
 			}
 
-			return true;
+            boundingVolumeHelper.BoundingVolume.FromVertices(vertices);
+            boundingVolumeHelper.BoundingVolume.Pad(0.1f);
+
+            return true;
 		}
 
 		/// <summary>
@@ -356,9 +362,9 @@ private Intersection TestIntersection(Ray ray)
 			
 				//	Find the point of intersection upon the plane, as a point 't' along
 				//	the ray.
-				Vertex point1OnPlane = vertices[face.Indices[0].Vertex];
-				Vertex point2OnPlane = vertices[face.Indices[1].Vertex];
-				Vertex point3OnPlane = vertices[face.Indices[2].Vertex];
+				Vertex point1OnPlane = Vertices[face.Indices[0].Vertex];
+				Vertex point2OnPlane = Vertices[face.Indices[1].Vertex];
+				Vertex point3OnPlane = Vertices[face.Indices[2].Vertex];
 				Vertex midpointOpp1 = (point2OnPlane + point3OnPlane) / 2;
 				Vertex midpointOpp2 = (point1OnPlane + point3OnPlane) / 2;
 				Vertex midpointOpp3 = (point1OnPlane + point2OnPlane) / 2;
@@ -520,7 +526,10 @@ public int Subdivide()
 
 			faces = newFaces;
 
-			return faces.Count;
+            boundingVolumeHelper.BoundingVolume.FromVertices(vertices);
+            boundingVolumeHelper.BoundingVolume.Pad(0.1f);
+
+            return faces.Count;
 		}
 
         /// <summary>
@@ -644,9 +653,22 @@ public List<Face> Faces
 		[Description("The vertices that make up the polygon."), Category("Polygon")]
 		public List<Vertex> Vertices
 		{
-			get {return vertices;}
-			set {vertices = value; }
-		}
+			get
+            {
+                return vertices;
+            }
+
+			set
+            {
+                vertices = value;
+
+                // TODO: [RS] Create bv when vertices changed. We need a mechanism that creates the bounding volume
+                //            if one verte is changed, removed or added. Use INotifyPropertyChanged for vertices or
+                //            some other observer pattern? 
+                boundingVolumeHelper.BoundingVolume.FromVertices(vertices);
+                boundingVolumeHelper.BoundingVolume.Pad(0.1f);
+            }
+        }
 
         /// <summary>
         /// Gets or sets the U vs.
@@ -706,9 +728,6 @@ public BoundingVolume BoundingVolume
         {
             get 
             {
-                //  todo; only create bv when vertices changed.
-                boundingVolumeHelper.BoundingVolume.FromVertices(vertices);
-                boundingVolumeHelper.BoundingVolume.Pad(0.1f); 
                 return boundingVolumeHelper.BoundingVolume;
             }
         }
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
index 1f2dbf79..1b1d8f91 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Primitives/Teapot.cs
@@ -5,14 +5,16 @@
 using SharpGL.SceneGraph.Assets;
 using SharpGL.SceneGraph.Helpers;
 using SharpGL.SceneGraph.Transformations;
+using System.Xml.Serialization;
 
 namespace SharpGL.SceneGraph.Primitives
 {
     /// <summary>
     /// The standard OpenGL teapot.
     /// </summary>
-    public class Teapot : 
-        SceneElement, 
+    public class Teapot :
+        SceneElement,
+        IVolumeBound,
         IHasObjectSpace,
         IRenderable,
         IHasMaterial
@@ -22,6 +24,11 @@ public class Teapot :
         /// </summary>
         private HasObjectSpaceHelper hasObjectSpaceHelper = new HasObjectSpaceHelper();
 
+        /// <summary>
+        /// Helps us implement IVolumeBound.
+        /// </summary>
+        private BoundingVolumeHelper boundingVolumeHelper = new BoundingVolumeHelper();
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Teapot"/> class.
         /// </summary>
@@ -31,6 +38,8 @@ public Teapot()
             Grid = 14;
             Scale = 1;
             FillType = OpenGL.GL_FILL;
+
+            BoundingVolume.FromSphericalVolume(new Vertex(), 1.75f);
         }
 
         /// <summary>
@@ -52,10 +61,10 @@ public void Render(OpenGL gl, RenderMode renderMode)
         /// <param name="type">The type.</param>
         public void Draw(OpenGL gl, int grid, double scale, uint type)
         {
-            float[, ,] p = new float[4, 4, 3];
-            float[, ,] q = new float[4, 4, 3];
-            float[, ,] r = new float[4, 4, 3];
-            float[, ,] s = new float[4, 4, 3];
+            float[,,] p = new float[4, 4, 3];
+            float[,,] q = new float[4, 4, 3];
+            float[,,] r = new float[4, 4, 3];
+            float[,,] s = new float[4, 4, 3];
 
             gl.PushAttrib(OpenGL.GL_ENABLE_BIT | OpenGL.GL_EVAL_BIT);
             gl.Enable(OpenGL.GL_AUTO_NORMAL);
@@ -75,131 +84,115 @@ public void Draw(OpenGL gl, int grid, double scale, uint type)
                     {
                         for (int l = 0; l < 3; l++)
                         {
-                            p[j,k,l] = cpdata[patchdata[i,(j * 4 + k)],l];
-                            q[j,k,l] = cpdata[patchdata[i,(j * 4 + (3 - k))],l];
+                            p[j, k, l] = cpdata[patchdata[i, (j * 4 + k)], l];
+                            q[j, k, l] = cpdata[patchdata[i, (j * 4 + (3 - k))], l];
                             if (l == 1)
-                                q[j,k,l] *= -1.0f;
+                                q[j, k, l] *= -1.0f;
                             if (i < 6)
                             {
-                                r[j,k,l] =
-                                  cpdata[patchdata[i,(j * 4 + (3 - k))],l];
+                                r[j, k, l] =
+                                  cpdata[patchdata[i, (j * 4 + (3 - k))], l];
                                 if (l == 0)
-                                    r[j,k,l] *= -1.0f;
-                                s[j,k,l] = cpdata[patchdata[i,(j * 4 + k)],l];
+                                    r[j, k, l] *= -1.0f;
+                                s[j, k, l] = cpdata[patchdata[i, (j * 4 + k)], l];
                                 if (l == 0)
-                                    s[j,k,l] *= -1.0f;
+                                    s[j, k, l] *= -1.0f;
                                 if (l == 1)
-                                    s[j,k,l] *= -1.0f;
+                                    s[j, k, l] *= -1.0f;
                             }
                         }
                     }
                 }
-                gl.Map2(OpenGL.GL_MAP2_TEXTURE_COORD_2, 0.0f, 1.0f, 2, 2, 0.0f, 1.0f, 4, 2,
-                  tex.Flatten());
-                gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4,
-                  p.Flatten());
+
+                gl.Map2(OpenGL.GL_MAP2_TEXTURE_COORD_2, 0.0f, 1.0f, 2, 2, 0.0f, 1.0f, 4, 2, tex.Flatten());
+                gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, p.Flatten());
                 gl.MapGrid2(grid, 0.0, 1.0, grid, 0.0, 1.0);
                 gl.EvalMesh2(type, 0, grid, 0, grid);
-                gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4,
-                  q.Flatten());
+                gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, q.Flatten());
                 gl.EvalMesh2(type, 0, grid, 0, grid);
+
                 if (i < 6)
                 {
-                    gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4,
-                      r.Flatten());
+                    gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, r.Flatten());
                     gl.EvalMesh2(type, 0, grid, 0, grid);
-                    gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4,
-                      s.Flatten());
+                    gl.Map2(OpenGL.GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, s.Flatten());
                     gl.EvalMesh2(type, 0, grid, 0, grid);
                 }
             }
 
-
             gl.PopMatrix();
             gl.PopAttrib();
         }
 
         int[,] patchdata =
-  {
-      /* rim */
-    {102, 103, 104, 105, 4, 5, 6, 7, 8, 9, 10, 11,
-      12, 13, 14, 15},
-      /* body */
-    {12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
-      24, 25, 26, 27},
-    {24, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36,
-      37, 38, 39, 40},
-      /* lid */
-    {96, 96, 96, 96, 97, 98, 99, 100, 101, 101, 101,
-      101, 0, 1, 2, 3,},
-    {0, 1, 2, 3, 106, 107, 108, 109, 110, 111, 112,
-      113, 114, 115, 116, 117},
-      /* bottom */
-    {118, 118, 118, 118, 124, 122, 119, 121, 123, 126,
-      125, 120, 40, 39, 38, 37},
-      /* handle */
-    {41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
-      53, 54, 55, 56},
-    {53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
-      28, 65, 66, 67},
-      /* spout */
-    {68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
-      80, 81, 82, 83},
-    {80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
-      92, 93, 94, 95}
-  };
+        {
+            /* rim */
+            {102, 103, 104, 105, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
+            /* body */
+            {12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27},
+            {24, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40},
+            /* lid */
+            {96, 96, 96, 96, 97, 98, 99, 100, 101, 101, 101, 101, 0, 1, 2, 3,},
+            {0, 1, 2, 3, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117},
+            /* bottom */
+            {118, 118, 118, 118, 124, 122, 119, 121, 123, 126, 125, 120, 40, 39, 38, 37},
+            /* handle */
+            {41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56},
+            {53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 28, 65, 66, 67},
+            /* spout */
+            {68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83},
+            {80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95}
+        };
 
-        float[,] cpdata = 
-  {
-      {0.2f, 0f, 2.7f}, {0.2f, -0.112f, 2.7f}, {0.112f, -0.2f, 2.7f}, {0f,
-      -0.2f, 2.7f}, {1.3375f, 0f, 2.53125f}, {1.3375f, -0.749f, 2.53125f},
-      {0.749f, -1.3375f, 2.53125f}, {0f, -1.3375f, 2.53125f}, {1.4375f,
-      0f, 2.53125f}, {1.4375f, -0.805f, 2.53125f}, {0.805f, -1.4375f,
-      2.53125f}, {0f, -1.4375f, 2.53125f}, {1.5f, 0f, 2.4f}, {1.5f, -0.84f,
-      2.4f}, {0.84f, -1.5f, 2.4f}, {0f, -1.5f, 2.4f}, {1.75f, 0f, 1.875f},
-      {1.75f, -0.98f, 1.875f}, {0.98f, -1.75f, 1.875f}, {0f, -1.75f,
-      1.875f}, {2f, 0f, 1.35f}, {2f, -1.12f, 1.35f}, {1.12f, -2f, 1.35f},
-      {0f, -2f, 1.35f}, {2f, 0f, 0.9f}, {2f, -1.12f, 0.9f}, {1.12f, -2f,
-      0.9f}, {0f, -2f, 0.9f}, {-2f, 0f, 0.9f}, {2f, 0f, 0.45f}, {2f, -1.12f,
-      0.45f}, {1.12f, -2f, 0.45f}, {0f, -2f, 0.45f}, {1.5f, 0f, 0.225f},
-      {1.5f, -0.84f, 0.225f}, {0.84f, -1.5f, 0.225f}, {0f, -1.5f, 0.225f},
-      {1.5f, 0f, 0.15f}, {1.5f, -0.84f, 0.15f}, {0.84f, -1.5f, 0.15f}, {0f,
-      -1.5f, 0.15f}, {-1.6f, 0f, 2.025f}, {-1.6f, -0.3f, 2.025f}, {-1.5f,
-      -0.3f, 2.25f}, {-1.5f, 0f, 2.25f}, {-2.3f, 0f, 2.025f}, {-2.3f, -0.3f,
-      2.025f}, {-2.5f, -0.3f, 2.25f}, {-2.5f, 0f, 2.25f}, {-2.7f, 0f,
-      2.025f}, {-2.7f, -0.3f, 2.025f}, {-3f, -0.3f, 2.25f}, {-3f, 0f,
-      2.25f}, {-2.7f, 0f, 1.8f}, {-2.7f, -0.3f, 1.8f}, {-3f, -0.3f, 1.8f},
-      {-3f, 0f, 1.8f}, {-2.7f, 0f, 1.575f}, {-2.7f, -0.3f, 1.575f}, {-3f,
-      -0.3f, 1.35f}, {-3f, 0f, 1.35f}, {-2.5f, 0f, 1.125f}, {-2.5f, -0.3f,
-      1.125f}, {-2.65f, -0.3f, 0.9375f}, {-2.65f, 0f, 0.9375f}, {-2f,
-      -0.3f, 0.9f}, {-1.9f, -0.3f, 0.6f}, {-1.9f, 0f, 0.6f}, {1.7f, 0f,
-      1.425f}, {1.7f, -0.66f, 1.425f}, {1.7f, -0.66f, 0.6f}, {1.7f, 0f,
-      0.6f}, {2.6f, 0f, 1.425f}, {2.6f, -0.66f, 1.425f}, {3.1f, -0.66f,
-      0.825f}, {3.1f, 0f, 0.825f}, {2.3f, 0f, 2.1f}, {2.3f, -0.25f, 2.1f},
-      {2.4f, -0.25f, 2.025f}, {2.4f, 0f, 2.025f}, {2.7f, 0f, 2.4f}, {2.7f,
-      -0.25f, 2.4f}, {3.3f, -0.25f, 2.4f}, {3.3f, 0f, 2.4f}, {2.8f, 0f,
-      2.475f}, {2.8f, -0.25f, 2.475f}, {3.525f, -0.25f, 2.49375f},
-      {3.525f, 0f, 2.49375f}, {2.9f, 0f, 2.475f}, {2.9f, -0.15f, 2.475f},
-      {3.45f, -0.15f, 2.5125f}, {3.45f, 0f, 2.5125f}, {2.8f, 0f, 2.4f},
-      {2.8f, -0.15f, 2.4f}, {3.2f, -0.15f, 2.4f}, {3.2f, 0f, 2.4f}, {0f, 0f,
-      3.15f}, {0.8f, 0f, 3.15f}, {0.8f, -0.45f, 3.15f}, {0.45f, -0.8f,
-      3.15f}, {0f, -0.8f, 3.15f}, {0f, 0f, 2.85f}, {1.4f, 0f, 2.4f}, {1.4f,
-      -0.784f, 2.4f}, {0.784f, -1.4f, 2.4f}, {0f, -1.4f, 2.4f}, {0.4f, 0f,
-      2.55f}, {0.4f, -0.224f, 2.55f}, {0.224f, -0.4f, 2.55f}, {0f, -0.4f,
-      2.55f}, {1.3f, 0f, 2.55f}, {1.3f, -0.728f, 2.55f}, {0.728f, -1.3f,
-      2.55f}, {0f, -1.3f, 2.55f}, {1.3f, 0f, 2.4f}, {1.3f, -0.728f, 2.4f},
-      {0.728f, -1.3f, 2.4f}, {0f, -1.3f, 2.4f}, {0f, 0f, 0f}, {1.425f,
-      -0.798f, 0f}, {1.5f, 0f, 0.075f}, {1.425f, 0f, 0f}, {0.798f, -1.425f,
-      0f}, {0f, -1.5f, 0.075f}, {0f, -1.425f, 0f}, {1.5f, -0.84f, 0.075f},
-      {0.84f, -1.5f, 0.075f}
-  };
+        float[,] cpdata =
+        {
+            {0.2f, 0f, 2.7f}, {0.2f, -0.112f, 2.7f}, {0.112f, -0.2f, 2.7f}, {0f,
+            -0.2f, 2.7f}, {1.3375f, 0f, 2.53125f}, {1.3375f, -0.749f, 2.53125f},
+            {0.749f, -1.3375f, 2.53125f}, {0f, -1.3375f, 2.53125f}, {1.4375f,
+            0f, 2.53125f}, {1.4375f, -0.805f, 2.53125f}, {0.805f, -1.4375f,
+            2.53125f}, {0f, -1.4375f, 2.53125f}, {1.5f, 0f, 2.4f}, {1.5f, -0.84f,
+            2.4f}, {0.84f, -1.5f, 2.4f}, {0f, -1.5f, 2.4f}, {1.75f, 0f, 1.875f},
+            {1.75f, -0.98f, 1.875f}, {0.98f, -1.75f, 1.875f}, {0f, -1.75f,
+            1.875f}, {2f, 0f, 1.35f}, {2f, -1.12f, 1.35f}, {1.12f, -2f, 1.35f},
+            {0f, -2f, 1.35f}, {2f, 0f, 0.9f}, {2f, -1.12f, 0.9f}, {1.12f, -2f,
+            0.9f}, {0f, -2f, 0.9f}, {-2f, 0f, 0.9f}, {2f, 0f, 0.45f}, {2f, -1.12f,
+            0.45f}, {1.12f, -2f, 0.45f}, {0f, -2f, 0.45f}, {1.5f, 0f, 0.225f},
+            {1.5f, -0.84f, 0.225f}, {0.84f, -1.5f, 0.225f}, {0f, -1.5f, 0.225f},
+            {1.5f, 0f, 0.15f}, {1.5f, -0.84f, 0.15f}, {0.84f, -1.5f, 0.15f}, {0f,
+            -1.5f, 0.15f}, {-1.6f, 0f, 2.025f}, {-1.6f, -0.3f, 2.025f}, {-1.5f,
+            -0.3f, 2.25f}, {-1.5f, 0f, 2.25f}, {-2.3f, 0f, 2.025f}, {-2.3f, -0.3f,
+            2.025f}, {-2.5f, -0.3f, 2.25f}, {-2.5f, 0f, 2.25f}, {-2.7f, 0f,
+            2.025f}, {-2.7f, -0.3f, 2.025f}, {-3f, -0.3f, 2.25f}, {-3f, 0f,
+            2.25f}, {-2.7f, 0f, 1.8f}, {-2.7f, -0.3f, 1.8f}, {-3f, -0.3f, 1.8f},
+            {-3f, 0f, 1.8f}, {-2.7f, 0f, 1.575f}, {-2.7f, -0.3f, 1.575f}, {-3f,
+            -0.3f, 1.35f}, {-3f, 0f, 1.35f}, {-2.5f, 0f, 1.125f}, {-2.5f, -0.3f,
+            1.125f}, {-2.65f, -0.3f, 0.9375f}, {-2.65f, 0f, 0.9375f}, {-2f,
+            -0.3f, 0.9f}, {-1.9f, -0.3f, 0.6f}, {-1.9f, 0f, 0.6f}, {1.7f, 0f,
+            1.425f}, {1.7f, -0.66f, 1.425f}, {1.7f, -0.66f, 0.6f}, {1.7f, 0f,
+            0.6f}, {2.6f, 0f, 1.425f}, {2.6f, -0.66f, 1.425f}, {3.1f, -0.66f,
+            0.825f}, {3.1f, 0f, 0.825f}, {2.3f, 0f, 2.1f}, {2.3f, -0.25f, 2.1f},
+            {2.4f, -0.25f, 2.025f}, {2.4f, 0f, 2.025f}, {2.7f, 0f, 2.4f}, {2.7f,
+            -0.25f, 2.4f}, {3.3f, -0.25f, 2.4f}, {3.3f, 0f, 2.4f}, {2.8f, 0f,
+            2.475f}, {2.8f, -0.25f, 2.475f}, {3.525f, -0.25f, 2.49375f},
+            {3.525f, 0f, 2.49375f}, {2.9f, 0f, 2.475f}, {2.9f, -0.15f, 2.475f},
+            {3.45f, -0.15f, 2.5125f}, {3.45f, 0f, 2.5125f}, {2.8f, 0f, 2.4f},
+            {2.8f, -0.15f, 2.4f}, {3.2f, -0.15f, 2.4f}, {3.2f, 0f, 2.4f}, {0f, 0f,
+            3.15f}, {0.8f, 0f, 3.15f}, {0.8f, -0.45f, 3.15f}, {0.45f, -0.8f,
+            3.15f}, {0f, -0.8f, 3.15f}, {0f, 0f, 2.85f}, {1.4f, 0f, 2.4f}, {1.4f,
+            -0.784f, 2.4f}, {0.784f, -1.4f, 2.4f}, {0f, -1.4f, 2.4f}, {0.4f, 0f,
+            2.55f}, {0.4f, -0.224f, 2.55f}, {0.224f, -0.4f, 2.55f}, {0f, -0.4f,
+            2.55f}, {1.3f, 0f, 2.55f}, {1.3f, -0.728f, 2.55f}, {0.728f, -1.3f,
+            2.55f}, {0f, -1.3f, 2.55f}, {1.3f, 0f, 2.4f}, {1.3f, -0.728f, 2.4f},
+            {0.728f, -1.3f, 2.4f}, {0f, -1.3f, 2.4f}, {0f, 0f, 0f}, {1.425f,
+            -0.798f, 0f}, {1.5f, 0f, 0.075f}, {1.425f, 0f, 0f}, {0.798f, -1.425f,
+            0f}, {0f, -1.5f, 0.075f}, {0f, -1.425f, 0f}, {1.5f, -0.84f, 0.075f},
+            {0.84f, -1.5f, 0.075f}
+        };
 
-        float[, ,] tex = 
-      {
-        { {0.0f, 0.0f},
-          {1.0f, 0.0f}},
-        { {0.0f, 1.0f},
-          {1.0f, 1.0f}}
+        float[,,] tex =
+        {
+            {{0.0f, 0.0f}, {1.0f, 0.0f}},
+            {{0.0f, 1.0f}, {1.0f, 1.0f}}
         };
 
         /// <summary>
@@ -244,10 +237,10 @@ public uint FillType
         /// <value>
         /// The material.
         /// </value>
-        public Material Material 
-        { 
-            get; 
-            set; 
+        public Material Material
+        {
+            get;
+            set;
         }
 
         /// <summary>
@@ -279,27 +272,19 @@ public LinearTransformation Transformation
             get { return hasObjectSpaceHelper.Transformation; }
             set { hasObjectSpaceHelper.Transformation = value; }
         }
-    }
 
-    /// <summary>
-    /// Extensions for Array type.
-    /// </summary>
-    public static class ArrayExtensions
-{
-  /// <summary>
-  /// Flattens the specified array.
-  /// </summary>
-  /// <typeparam name="T">The array type.</typeparam>
-  /// <param name="array">The array.</param>
-  /// <returns>The flattened array.</returns>
-        public static T[] Flatten<T>(this T[,,] array)
-  where T : struct
+        /// <summary>
+        /// Gets the bounding volume.
+        /// </summary>
+        [Browsable(false)]
+        [XmlIgnore]
+        public BoundingVolume BoundingVolume
         {
-            int size = Marshal.SizeOf(array[0, 0, 0]);
-            int totalSize = Buffer.ByteLength(array);
-            T[] result = new T[totalSize / size];
-            Buffer.BlockCopy(array, 0, result, 0, totalSize);
-            return result;
+            get
+            {
+                return boundingVolumeHelper.BoundingVolume;
+            }
         }
-}
+
+    }
 }
\ No newline at end of file
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Disk.cs b/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Disk.cs
index 5ee2ebc5..28ac0eda 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Disk.cs
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/Quadrics/Disk.cs
@@ -1,6 +1,8 @@
 using System;
 using System.ComponentModel;
 using SharpGL.SceneGraph.Core;
+using System.Xml.Serialization;
+using SharpGL.SceneGraph.Helpers;
 
 namespace SharpGL.SceneGraph.Quadrics
 {
@@ -8,7 +10,7 @@ namespace SharpGL.SceneGraph.Quadrics
     /// The Disk class wraps both the disk and partial disk quadrics.
     /// </summary>
     [Serializable()]
-    public class Disk : Quadric
+    public class Disk : Quadric, IVolumeBound
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="Disk"/> class.
@@ -16,6 +18,9 @@ public class Disk : Quadric
         public Disk() 
         { 
             Name = "Disk";
+
+            //  Set the outer radius via the property, sets the BV.
+            OuterRadius = 1.0;
         }
 
         /// <summary>
@@ -41,6 +46,11 @@ public override void Render(OpenGL gl, RenderMode renderMode)
         int slices = 16;
         int loops = 20;
 
+        /// <summary>
+        /// Helps us implement IVolumeBound.
+        /// </summary>
+        private BoundingVolumeHelper boundingVolumeHelper = new BoundingVolumeHelper();
+
         /// <summary>
         /// Gets or sets the inner radius.
         /// </summary>
@@ -63,8 +73,16 @@ public double InnerRadius
         [Description("Radius of the disk."), Category("Quadric")]
         public double OuterRadius
         {
-            get { return outerRadius; }
-            set { outerRadius = value; }
+            get
+            {
+                return outerRadius;
+            }
+
+            set
+            {
+                outerRadius = value;
+                BoundingVolume.FromCylindricalVolume(new Vertex(), 0f, (float)outerRadius, (float)outerRadius);
+            }
         }
 
         /// <summary>
@@ -118,5 +136,16 @@ public int Loops
             get { return loops; }
             set { loops = value; }
         }
+
+        /// <summary>
+        /// Gets the bounding volume.
+        /// </summary>
+        [Browsable(false)]
+        [XmlIgnore]
+        public BoundingVolume BoundingVolume
+        {
+            get { return boundingVolumeHelper.BoundingVolume; }
+        }
+
     }
 }
\ No newline at end of file
diff --git a/source/SharpGL/Core/SharpGL.SceneGraph/SharpGL.SceneGraph.csproj b/source/SharpGL/Core/SharpGL.SceneGraph/SharpGL.SceneGraph.csproj
index 93df5b3d..cb803634 100644
--- a/source/SharpGL/Core/SharpGL.SceneGraph/SharpGL.SceneGraph.csproj
+++ b/source/SharpGL/Core/SharpGL.SceneGraph/SharpGL.SceneGraph.csproj
@@ -92,6 +92,7 @@
     <Compile Include="OpenGLSceneGraphExtensions.cs" />
     <Compile Include="ParticleSystem\Particle.cs" />
     <Compile Include="ParticleSystem\ParticleSystems.cs" />
+    <Compile Include="Primitives\ArrayExtensions.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Assets\Asset.cs" />
     <Compile Include="Assets\Material.cs" />