In this post, I explain the basic Windows Presentation Foundation programming elements of a 3D scene in C#. The C# code that I use for demonstration creates a simple tetrahedron model and rotates it around the vertical axis.
To create the project, follow these steps:
- Begin with the project from our prior blog post, or create a new WPF project.
- Add a class file to the project: left-click PROJECT in the menubar and left-click Add Class… in the submenu.
- This pops up the Add New Item dialog. Select Installed->Visual C# Items in the left-hand pane.
- Then left-click Class in the center pane to select it.
- Finally, rename the class by left-clicking the text box next to Name: at the bottom of the window and entering CScene3d.cs. Finish adding the class by left-clicking the Add button.
- Next, copy the code for “CScene3D.cs” below into the file of the same name in your project.
- Finally, finish the code by adding this line to “Program.cs” as shown in the code below to allow the window to display the 3D scene:
qWindow.Content = TestScenes.Test5();
- Compile and execute the program by left-clicking DEBUG in the menubar and left-clicking Start Without Debugging in the submenu. After a few seconds, the code will be compiled and a window will pop up displaying a rotating tetrahedron.
The WPF scene creation in “CScene3D.cs” consists of a few basic steps, which can be outlined as follows:
- Create a camera and add it.
- Create a lighting model and add it.
- Create a geometric model and add it
- Create points, triangles, and normals
- Set the material properties
- Create and apply transforms
For simplicity, I have skipped some steps, like adding normals, and accepted default values for much of the rest. At the end, I have collected components to added them appropriately. Pay close attention to that.
Program.cs
using System; using System.Windows; namespace ConsoleApplication { class Program { [STAThread] static void Main(string[] args) { Window qWindow = new Window(); qWindow.Title = "WPF in Console"; qWindow.Width = 400; qWindow.Height = 300; qWindow.Content = CScene3D.Test(); qWindow.ShowDialog(); } } }
CScene3D.cs
using System; using System.Windows; using System.Windows.Controls; using System.Windows.Media; using System.Windows.Media.Media3D; using System.Windows.Media.Animation; namespace ConsoleApplication { class CScene3D { // Animation - Tetrahedron (upright, looking slightly up from below) public static Viewport3D Test() { // Define the camera PerspectiveCamera myPCamera = new PerspectiveCamera(); myPCamera.Position = new Point3D(0, .2, 3); // Define a lighting model DirectionalLight myDirectionalLight = new DirectionalLight(); // Define the geometry const double kdSqrt2 = 1.4142135623730950488016887242097; const double kdSqrt6 = 2.4494897427831780981972840747059; // Create a collection of vertex positions Point3DCollection myPositionCollection = new Point3DCollection(); myPositionCollection.Add(new Point3D(0.0, 1.0, 0.0)); myPositionCollection.Add(new Point3D(2.0 * kdSqrt2 / 3.0, -1.0 / 3.0, 0.0)); myPositionCollection.Add(new Point3D(-kdSqrt2 / 3.0, -1.0 / 3.0, kdSqrt6 / 3.0)); myPositionCollection.Add(new Point3D(-kdSqrt2 / 3.0, -1.0 / 3.0, -kdSqrt6 / 3.0)); // Create a collection of triangle indices Int32Collection myTriangleIndicesCollection = new Int32Collection(); // Triangle myTriangleIndicesCollection.Add(0); myTriangleIndicesCollection.Add(2); myTriangleIndicesCollection.Add(1); // Triangle myTriangleIndicesCollection.Add(0); myTriangleIndicesCollection.Add(1); myTriangleIndicesCollection.Add(3); // Triangle myTriangleIndicesCollection.Add(0); myTriangleIndicesCollection.Add(3); myTriangleIndicesCollection.Add(2); // Triangle myTriangleIndicesCollection.Add(1); myTriangleIndicesCollection.Add(2); myTriangleIndicesCollection.Add(3); MeshGeometry3D myMeshGeometry3D = new MeshGeometry3D(); myMeshGeometry3D.Positions = myPositionCollection; myMeshGeometry3D.TriangleIndices = myTriangleIndicesCollection; // Apply the mesh to the geometry model. GeometryModel3D myGeometryModel = new GeometryModel3D(); myGeometryModel.Geometry = myMeshGeometry3D; // Define the material for the geometry SolidColorBrush qColorBrush = new SolidColorBrush(Color.FromArgb(255, 0, 255, 0)); DiffuseMaterial myMaterial = new DiffuseMaterial(qColorBrush); myGeometryModel.Material = myMaterial; // Define the transformation, if any. In this case, we use an animated transformation RotateTransform3D myRotateTransform = new RotateTransform3D(new AxisAngleRotation3D(new Vector3D(0, 1, 0), 1)); DoubleAnimation myAnimation = new DoubleAnimation(); myAnimation.From = 1; myAnimation.To = 361; myAnimation.Duration = new Duration(TimeSpan.FromMilliseconds(5000)); myAnimation.RepeatBehavior = RepeatBehavior.Forever; myRotateTransform.Rotation.BeginAnimation(AxisAngleRotation3D.AngleProperty, myAnimation); myGeometryModel.Transform = myRotateTransform; // Collect the components Model3DGroup myModel3DGroup = new Model3DGroup(); myModel3DGroup.Children.Add(myDirectionalLight); myModel3DGroup.Children.Add(myGeometryModel); ModelVisual3D myModelVisual3D = new ModelVisual3D(); myModelVisual3D.Content = myModel3DGroup; Viewport3D myViewport3D = new Viewport3D(); myViewport3D.Children.Add(myModelVisual3D); myViewport3D.Camera = myPCamera; return myViewport3D; } } }
Tags: 3d, C#, computer programming, geometry, graphics, lighting, polygon, tetrahedron, transformation, windows presentation foundation, wpf
Michael HallBy: Michael Hall
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