public ScreenManager()
{
screens = new Dictionary<String, Screen>();
CurrentScreen = null;
TransitionNextScreen = null;
}
/* Transition the current active screen to the one specified
* The string name is the name used when added into the hash
*/
public void Transition(String name)
{
Screen ret = null;
screens.TryGetValue(name, out ret);
if (ret != null)
{
TransitionNextScreen = ret;
if (CurrentScreen != null) CurrentScreen.TransitionFrom();
TransitionNextScreen.TransitionTo();
transition = true;
if (CurrentScreen != null)
{
fadingOut = true;
alpha = 0.0f;
}
else
{
CurrentScreen = ret;
fadingOut = false;
alpha = 1.0f;
}
}
}
/* Add a Screen into the screen manager
* The name is a string hash to the Screen Object
*/
public void AddScreen(String name, Screen screen)
{
screens.Add(name, screen);
}
/* Update the correct screen.
* This will only send mouse clicks and update events to the active screen.
*/
public void Update(GameTime gameTime)
{
if (CurrentScreen == null) return;
if (transition)
{
// Fading out the current screen
if (fadingOut)
{
double dtime = gameTime.ElapsedGameTime.TotalSeconds;
alpha = alpha + (float)(dtime / CurrentScreen.OutTransitionTime);
// Do the swap (in the secrecy of the darkness!)
if (alpha > 1.0)
{
alpha = 1.0f;
fadingOut = false;
CurrentScreen = TransitionNextScreen;
TransitionNextScreen = null;
}
}
// Fading in the new screen
else
{
double dtime = gameTime.ElapsedGameTime.TotalSeconds;
alpha = alpha - (float)(dtime / CurrentScreen.InTransitionTime);
// Do the swap (in the secrecy of the darkness!)
if (alpha <= 0.0)
{
alpha = 0.0f;
transition = false;
}
}
}
if (!fadingOut) CurrentScreen.Update(gameTime);
}