Unsafe Screen Area Overlay Drawable Game Component

Component that overlays the screen to illustrate the recommended margins for game content. All game text and action should occur inside the displayed margins to account for the differing display area of monitors, TV, etc.

/// <summary>
/// Component that renders the unsafe screen areas for any content (10%)
/// and for action or text (20%).
/// </summary>
public class UnsafeAreaOverlayComponent : DrawableGameComponent
{
  /// <summary>
  /// Color for the area unsafe for game action or text.
  /// </summary>
  public Color NoActionAreaColor
  {
    get { return noActionAreaColor; }
    set { noActionAreaColor = value; }
  }
 
  /// <summary>
  /// Color for the area unsafe for game action or text.
  /// </summary>
  private Color noActionAreaColor;
 
  /// <summary>
  /// Color for the area unsafe for any content.
  /// </summary>
  public Color UnsafeAreaColor
  {
    get { return unsafeAreaColor; }
    set { unsafeAreaColor = value; }
  }
 
  /// <summary>
  /// Color for the area unsafe for any content.
  /// </summary>
  private Color unsafeAreaColor;
 
  /// <summary>
  /// Renders safe-zone overlay.
  /// </summary>
  private SpriteBatch spriteBatch;
 
  /// <summary>
  /// Texture to render (1x1).
  /// </summary>
  private Texture2D texture;
 
  /// <summary>
  /// Defines the screen area unsafe for action.
  /// </summary>
  private Rectangle[] noActionAreaParts;
 
  /// <summary>
  /// Defines the screen area unsafe for any content.
  /// </summary>
  private Rectangle[] unsafeAreaParts;
 
  /// <summary>
  /// Create a new <c>UnsafeAreaOverlayComponent</c>.
  /// </summary>
  /// <param name="game">Containing game.</param>
  public UnsafeAreaOverlayComponent(Game game) : base(game)
  {
    // draw this last
    DrawOrder = Int32.MaxValue;
 
    // default the unsafe area colors, semi-transparent
    noActionAreaColor = new Color(255, 0, 0, 127);
    unsafeAreaColor = new Color(255, 255, 0, 127);
  }
 
  /// <summary>
  /// Load component content.
  /// </summary>
  protected override void LoadContent()
  {
    spriteBatch = new SpriteBatch(GraphicsDevice);
 
    // generate a 1x1 texture
    texture = new Texture2D(GraphicsDevice, 1, 1, 1, TextureUsage.None, 
                            SurfaceFormat.Color);
    Color[] textureData = new Color[1];
    textureData[0] = Color.White;
    texture.SetData<Color>(textureData);
 
    // get viewport size and the offset percentage
    int width = GraphicsDevice.Viewport.Width;
    int height = GraphicsDevice.Viewport.Height;
    int dw = (int)(width * 0.05);
    int dh = (int)(height * 0.05);
 
    // generate the area unsafe for game action or text
    noActionAreaParts = new Rectangle[4];
    noActionAreaParts[0] = new Rectangle(0, 0, width, dh);
    noActionAreaParts[1] = new Rectangle(0, height - dh, width, dh);
    noActionAreaParts[2] = new Rectangle(0, dh, dw, height - 2*dh);
    noActionAreaParts[3] = new Rectangle(width - dw, dh, dw, height - 2*dh);
 
    // generate the area not safe for anything
    unsafeAreaParts = new Rectangle[4];
    unsafeAreaParts[0] = new Rectangle(dw, dh, width - 2*dw, dh);
    unsafeAreaParts[1] = new Rectangle(dw, height - 2*dh, width - 2*dw, dh);
    unsafeAreaParts[2] = new Rectangle(dw, 2 * dh, dw, height-4 * dh);
    unsafeAreaParts[3] = new Rectangle(width - 2*dw, 2*dh, dw, height - 4*dh);
  }
 
  /// <summary>
  /// Draw the component.
  /// </summary>
  /// <param name="gameTime">Game time.</param>
  public override void Draw(GameTime gameTime)
  {
    // NOTE: SaveStateMode.SaveState should only be used when debugging
    // see http://blogs.msdn.com/shawnhar/archive/2006/11/13/spritebatch-and-renderstates.aspx
    spriteBatch.Begin(SpriteBlendMode.AlphaBlend, SpriteSortMode.FrontToBack,
                      SaveStateMode.SaveState);
 
    // render the area unsafe for action or game text
    for(int i = 0; i < noActionAreaParts.Length; i++)
    {
      spriteBatch.Draw(texture, noActionAreaParts[i], noActionAreaColor);
    }
 
    // render the area unsafe for any game content
    for(int i = 0; i < unsafeAreaParts.Length; i++)
    {
      spriteBatch.Draw(texture, unsafeAreaParts[i], unsafeAreaColor);
    }
 
    spriteBatch.End();
  }
}