How to correctly calculate FPS in XNA?
- by Tomek Tarczynski
I wrote a component to display current FPS.
The most important part of it is:
public override void Update(GameTime gameTime)
{
elapseTime += (float)gameTime.ElapsedRealTime.TotalSeconds;
frameCounter++;
if (elapseTime > 1)
{
FPS = frameCounter;
frameCounter = 0;
elapseTime = 0;
}
base.Update(gameTime);
}
In most cases it works ok, but recently I had a problem.
When I put following code into Update method of game strange thing starts to happen.
if (threadPath == null || threadPath.ThreadState != ThreadState.Running)
{
ThreadStart ts = new ThreadStart(current.PathFinder.FindPaths);
threadPath = new Thread(ts);
threadPath.Priority = ThreadPriority.Highest;
threadPath.Start();
}
Main idea of this code is to run pathFinding algorithm in different thread all the time.
By strange things I mean that sometimes FPS drasticly decreases, this is obvious, but displayed FPS changes more often than once a second. If I understand this code FPS can't change more often than once a second.
Can someone explain me what's going on?
