Bits & Bytes

Posts Tagged ‘C#’

Programming a 3D Scene in WPF with C#

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.

RotatingTetra

To create the project, follow these steps:

  1. Begin with the project from our prior blog post, or create a new WPF project.
    OpenProject
  2. Add a class file to the project: left-click PROJECT in the menubar and left-click Add Class… in the submenu.
    ProjectAddClass
  3. This pops up the Add New Item dialog. Select Installed->Visual C# Items in the left-hand pane.
    VisualCsharpItems
  4. Then left-click Class in the center pane to select it.
    Class
  5. 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.RenameClass
  6. Next, copy the code for “CScene3D.cs” below into the file of the same name in your project.
  7. 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();
  8. 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.DemoImage

The WPF scene creation in “CScene3D.cs” consists of a few basic steps, which can be outlined as follows:


  1. Create a camera and add it.
  2. Create a lighting model and add it.
  3. Create a geometric model and add it
    1. Create points, triangles, and normals
    2. Set the material properties
    3. 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;
        }
    }
}

Using WPF in a C# Console Application

In this blog post, I demonstrate how to create a C# console application that can open a Windows Presentation Foundation window so that we can draw WPF graphics in a console program. The methodology is important because it can be used to add Windows Presentation Foundation classes to any type of C# project.

  1. To start, you should have a default C# Console Application project open. If you do not know how to create a C# console application project, you can consult our prior blog post on that topic.
    OpenProject
  2. Once you have a console application project open, it should have a Program.cs file with the following code inside it:
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    
    namespace ConsoleApplication {
        class Program {
            static void Main(string[] args) {
            }
        }
    }
    

    As the namespace indicates, the project was created using the default project name ConsoleApplication.

  3. We need to change some of the code. Begin by replacing the lines
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    

    with the line

    using System.Windows;
    
  4. Directly after the line
    class Program {

    add this line

    [STAThread]
  5. Directly after the line
    static void Main(string[] args) {

    add the following lines of code:

    Window qWindow = new Window();
    qWindow.Title = "WPF in Console";
    qWindow.Width = 400;
    qWindow.Height = 300;
    qWindow.ShowDialog();
    

    The final program should look like this

    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.ShowDialog();
            }
        }
    }
    
  6. That is all of the code. Next, we need to add the libraries that the program uses. To do this, right-click References in the Solution Explorer pane on the right of the screen, and left-click Add Reference… in the context menu that pops up.
  7. That will open the Reference Manager dialog shown below. Navigate to Assemblies->Framework by left-clicking them, and then left-click the check boxes next to PresentationCore, PresentationFramework, and WindowsBase. Finish by left-clicking the OK button.
    ReferenceManager
  8. Now the code and project are ready. To compile and execute the program, left-click DEBUG in the menubar and left-click Start Without Debugging in the submenu. When it finishes compiling, you should see this window:
    Output

Perhaps the most important line of code in this program is [STAThread]. Without this, you can not compile WPF code. STA stands for Single Threaded Apartment. It is a directive for COM. the Component Object Model. If that does not makes sense, feel free to ignore it.

The code inside the Main() function, creates a Window object, sets the text in the title bar, sets the size of the window to 400 by 300 pixels, and causes the window to be displayed with the call to ShowDialog().

Creating a C# Console Application in Visual Studio 2013

This post explains how to create a simple console application in C# and make it print out a message. Console applications are the simplest applications. So, this is the perfect place to start if you have no prior knowledge of C#.

  1. Navigate to the Start menu by left-clicking the Windows icon in the lower-left corner of your Desktop screen.
    Desktop
  2. Then left-click the down arrow in the lower-left corner to go the Apps section and find the Visual Studio 2013 icon.
  3. Left-click the Visual Studio 2013 icon to open the Visual Studio 2013 application.
    StartMenu
  4. Left-click FILE in the menubar, mouse over New in the submenu, and left-click Project in the submenu to open the New Project dialog.
    NewProject
  5. Select Installed->Templates->Visual C#->Windows in the left-hand pane.
    Installed_Templates
  6. Then left-click Console Application in the center pane.
    ConsoleAppplication
  7. If you want to accept the default project name and location, left-click the OK button to finish creating the console application. Otherwise, you can first:
    1. Set the name of the project in the field next to “Name:” near the bottom of the dialog.
    2. Select a location by left-clicking the “Browse” button.
  8. Now the project is created. To get the program to do something, add the line
    Console.WriteLine("God is Love!");

    to the code file “Program.cs” so that the final code looks like this:

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    
    namespace ConsoleApplication {
        class Program {
            static void Main(string[] args) {
                Console.WriteLine("God is Love!");
            }
        }
    }
    
  9. To compile and run the program, left-click DEBUG in the menubar and left-click Start Without Debugging in the submenu.
    StartWithoutDebugging
  10. When the program finishes compiling and runs, a console window should open like this one with the message “God is Love!” inside of it.
    Output