/// <summary>
/// Updates the menu entry.
/// </summary>
public virtual void Update(MenuScreen screen, bool isSelected, GameTime gameTime)
{
// When the menu selection changes, entries gradually fade between
// their selected and deselected appearance, rather than instantly
// popping to the new state.
var fadeSpeed = (float)gameTime.ElapsedGameTime.TotalSeconds * 4;
_selectionFade = isSelected ? Math.Min(_selectionFade + fadeSpeed, 1) : Math.Max(_selectionFade - fadeSpeed, 0);
}
/// <summary>
/// Draws the menu entry. This can be overridden to customize the appearance.
/// </summary>
public virtual void Draw(MenuScreen screen, bool isSelected, GameTime gameTime)
{
// Draw the selected entry in yellow, otherwise white.
var color = isSelected ? Color.Yellow : Color.LightGray;
// Pulsate the size of the selected menu entry.
var time = gameTime.TotalGameTime.TotalSeconds;
var pulsate = (float)Math.Sin(time * 6) + 1;
var scale = 1 + pulsate * 0.05f * _selectionFade;
// Modify the alpha to fade text out during transitions.
color *= screen.TransitionAlpha;
// Draw text, centered on the middle of each line.
var screenManager = screen.ScreenManager;
var spriteBatch = screenManager.SpriteBatch;
var font = screenManager.Font;
// ReSharper disable PossibleLossOfFraction
var origin = new Vector2(0, font.LineSpacing / 2);
// ReSharper restore PossibleLossOfFraction
spriteBatch.DrawString(font, _text, _position, color, 0,
origin, scale, SpriteEffects.None, 0);
}
/// <summary>
/// Queries how wide the entry is, used for centering on the screen.
/// </summary>
public virtual int GetWidth(MenuScreen screen)
{
return (int)screen.ScreenManager.Font.MeasureString(Text).X;
}
/// <summary>
/// Queries how much space this menu entry requires.
/// </summary>
public virtual int GetHeight(MenuScreen screen)
{
return screen.ScreenManager.Font.LineSpacing;
}
