/// <summary>
/// Allows the screen the chance to position the menu entries. By default
/// all menu entries are lined up in a vertical list, centered on the screen.
/// </summary>
protected virtual void UpdateMenuEntryLocations()
{
// Make the menu slide into place during transitions, using a
// power curve to make things look more interesting (this makes
// the movement slow down as it nears the end).
float transitionOffset = (float)Math.Pow(TransitionPosition, 2);
// start at Y = 175; each X value is generated per entry
Vector2 position = new Vector2(0f, 175f);
// update each menu entry's location in turn
for (int i = 0; i < menuEntries.Count; i++)
{
MenuEntry menuEntry = menuEntries[i];
// each entry is to be centered horizontally
position.X = ScreenManager.GraphicsDevice.Viewport.Width / 2 - menuEntry.GetWidth(this) / 2;
if (ScreenState == ScreenState.TransitionOn)
{
position.X -= transitionOffset * 256;
}
else
{
position.X += transitionOffset * 512;
}
// set the entry's position
menuEntry.Position = position;
// move down for the next entry the size of this entry
position.Y += menuEntry.GetHeight(this);
}
}
/// <summary>
/// Draws the menu.
/// </summary>
public override void Draw(GameTime gameTime)
{
SpriteBatch spriteBatch = ScreenManager.SpriteBatch;
SpriteFont font = ScreenManager.Font;
Vector2 position = new Vector2(100, 150);
// Make the menu slide into place during transitions, using a
// power curve to make things look more interesting (this makes
// the movement slow down as it nears the end).
float transitionOffset = (float)Math.Pow(TransitionPosition, 2);
if (ScreenState == ScreenState.TransitionOn)
{
position.X -= transitionOffset * 256;
}
else
{
position.X += transitionOffset * 512;
}
spriteBatch.Begin();
// Draw each menu entry in turn.
for (int i = 0; i < menuEntries.Count; i++)
{
MenuEntry menuEntry = menuEntries[i];
bool isSelected = IsActive && (i == selectedEntry);
menuEntry.Draw(this, position, isSelected, gameTime);
position.Y += menuEntry.GetHeight(this);
}
// Draw the menu title.
Vector2 titlePosition = new Vector2(533, 80);
Vector2 titleOrigin = font.MeasureString(menuTitle) / 2;
Color titleColor = new Color(192, 192, 192, TransitionAlpha);
float titleScale = 1.25f;
titlePosition.Y -= transitionOffset * 100;
spriteBatch.DrawString(font, menuTitle, titlePosition, titleColor, 0,
titleOrigin, titleScale, SpriteEffects.None, 0);
spriteBatch.End();
}