3D Basics using Silverlight-5 and XNA (Part 2)

using System.Windows.Controls;
using System.Windows.Graphics;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;

namespace Polyhedron
{
  public partial class MainPage : UserControl
  {
    private float aspectRatio = 1f;
    private Polyhedron[] polyhedrons;

    public MainPage()
    {
      InitializeComponent();
    }

    private void drawingSurface1_Loaded(object sender, System.Windows.RoutedEventArgs e)
    {
      polyhedrons = new Polyhedron[]
      {
        new Polyhedron(Polyhedra.CubeCorners, Polyhedra.CubeFaces, new Color(0, 0, 1f)),
        new Polyhedron(Polyhedra.TetrahedronCorners, Polyhedra.TetrahedronFaces, new Color(1f, 1f, 0)),
        new Polyhedron(Polyhedra.OctahedronCorners, Polyhedra.OctahedronFaces, new Color(0, 1f, 1f)),
        new Polyhedron(Polyhedra.DodecahedronCorners, Polyhedra.DodecahedronFaces, new Color(0, 1f, 0)),
        new Polyhedron(Polyhedra.IcosahedronCorners, Polyhedra.IcosahedronFaces, new Color(1f, 0, 0))
      };
    }

    private void drawingSurface1_SizeChanged(object sender, System.Windows.SizeChangedEventArgs e)
    {
      aspectRatio = (float)(drawingSurface1.ActualWidth / drawingSurface1.ActualHeight);
    }

    private void drawingSurface1_Draw(object sender, DrawEventArgs e)
    {
      GraphicsDevice g = GraphicsDeviceManager.Current.GraphicsDevice;
      Matrix view = Matrix.CreateLookAt(new Vector3(0, 0, 8.0f), Vector3.Zero, Vector3.Up);
      Matrix projection = Matrix.CreatePerspectiveFieldOfView(0.85f, aspectRatio, 0.01f, 1000.0f);

      Vector3 axis = new Vector3(-0.5f, 1, -0.5f);
      axis.Normalize();
      Matrix rotate1 = Matrix.CreateFromQuaternion(Quaternion.CreateFromAxisAngle(axis, (float)e.TotalTime.TotalSeconds * 3));
      Matrix translate = Matrix.CreateTranslation(2, 0, 0);
      for (int i = 0; i < polyhedrons.Length; i++)
      {
        Matrix rotate2 = Matrix.CreateRotationZ(i * MathHelper.TwoPi / 5 + (float)e.TotalTime.TotalSeconds / 3);
        polyhedrons[i].World = rotate1 * translate * rotate2;
      }
      g.Clear(new Color(0.8f, 0.8f, 0.8f, 1.0f));
      foreach (Polyhedron polyhedron in polyhedrons)
        polyhedron.Draw(view, projection);
      e.InvalidateSurface();
    }
  }
}