c# - Silverlight/XNA 动画滞后

Question

当我使用 XNA Framework(对于 Windows Phone)时，我的游戏运行完美，但是当我迁移到 Silverlight/XNA Framework 时，我遇到了动画滞后的问题。问题如下:当我将固定时间步长设置为 GameTimer (timer.UpdateInterval = TimeSpan.FromTicks(333333)) 时，实际时间步长不固定并且计时器事件(OnUpdate、OnDraw)以不同的时间间隔触发。此代码更清楚地显示了我的问题:

Silverlight/XNA Framework:(动画滞后):

TimeSpan curNow;
TimeSpan lastUpdate;
TimeSpan lastDraw;

public GamePage()
{
    timer = new GameTimer();
    timer.UpdateInterval = TimeSpan.FromTicks(333333);
    timer.Update += OnUpdate;
    timer.Draw += OnDraw;
}

private void OnUpdate(object sender, GameTimerEventArgs e)
{    
    curNow = new TimeSpan(DateTime.Now.Ticks);
    TimeSpan elapsed=e.ElapsedTime;//Always constant and has value: 33ms
    TimeSpan realElapsed =  curNow  -  lastUpdate;//Real elapsed time always changing and has a value between: 17-39ms (sometimes more then 39ms)
    lastUpdate =  curNow;
}

private void OnDraw(object sender, GameTimerEventArgs e)
{
    curNow = new TimeSpan(DateTime.Now.Ticks);
    TimeSpan elapsed=e.ElapsedTime;//Always changing and has a value between: 17-39ms (sometimes more then 39ms)
    TimeSpan realElapsed =  curNow  -lastDraw;//Always changing and has a value between: 17-39ms (sometimes more then 39ms)
    lastDraw=  curNow;
}

XNA 框架:(一切正常):

TimeSpan curNow;
TimeSpan lastUpdate;
TimeSpan lastDraw;

public Game()
{
    // Frame rate is 30 fps by default for Windows Phone.
    TargetElapsedTime = TimeSpan.FromTicks(333333);
}

protected override void Update(GameTime gameTime)
{    
    curNow = new TimeSpan(DateTime.Now.Ticks);
    TimeSpan elapsed=gameTime.ElapsedGameTime;//Always constant and has value: 33ms
    TimeSpan realElapsed =  curNow - lastUpdate;//Real elapsed time has a value between: 34-35ms (sometimes more then 35ms)
    lastUpdate = curNow;
}

protected override void Draw(GameTime gameTime)
{    
    curNow = new TimeSpan(DateTime.Now.Ticks);
    TimeSpan elapsed=gameTime.ElapsedGameTime ;//Value between: 33-34ms (sometimes more then 34ms)
    TimeSpan realElapsed = curNow - lastDraw;//Value between: 34-35ms (sometimes more then 35ms)
    lastDraw = curNow;
}

Answer 1

更改为

TimeSpan.Zero;

是的，我知道这感觉很奇怪，而且确实如此。从一些官方游戏指南中得到它。除非我使用它，否则我的游戏会像疯了似的滞后。