Game Loop, calculate the Frames Per Second.

[Dirk94]

Ok, so first of all I would like to say that I'm still very 'Noob-ish' when it comes to programming in Java.

I'm creating a simple game, however I thought it would be a nice challenge to display the frames per second in my game.
But all the articles about it are really complex (for me) , and nobody seems to have a game loop the way I do.
This is what my game loop looks like:

My Main class extends the JPanel

 public class Main extends JPanel {

Also in my main class the game loop, it uses the default repaint() method. In wich I draw all the images etc.

public void run() {
  while (true) {
    long time = System.currentTimeMillis();
 
    repaint();
 
    time = (1000 / Globals.maxFPS) - (System.currentTimeMillis() - time);
 
    if (time > 0) {
      try {
        Thread.sleep(time);
      } catch (Exception e) }
    }
  }
}

My first thought was to calculate the FPS using the time variable, however no mather how slow the game goes time is always 16. So I realy don't understand how I should calculate the FPS in this game loop.

If you need any more information I'll be happy to give it

Thanks in Advance,
Dirk

[KevinWorkman]

There are a couple ways to do this.

Each frame, calculate the time (in seconds) it has been since the last frame. Divide 1 by that number, and that's your momentary fps.

Do a similar calculation, only spread out over more time- every x number of frames, calculate how long it's been since the last x frames. Take x divided by that time, and that's your fps.

Or do it the other way around- every second, calculate how many frames have passed. That's your fps. Or every 5 seconds, divided by 5.

[Norm]

it uses the default repaint() method. In wich I draw all the images etc.

Do you have a repaint() method with your code in it? That is not normal and I don't know how it would work.
The call to the repaint() method will return without much delay.
(System.currentTimeMillis() - time) will be 0 most of the time.

I'm not sure I understand your problem. Where is the FPS value shown?