public override void Shutdown()
{
base.Shutdown();
if ( this.TrayManager != null )
this.TrayManager.Dispose();
if ( this.CameraManager != null )
this.CameraManager = null;
// restore settings we may have changed, so as not to affect other samples
MaterialManager.Instance.SetDefaultTextureFiltering( TextureFiltering.Bilinear );
MaterialManager.Instance.DefaultAnisotropy = 1;
}