Force Graphics Sync (?)

[Acidic]

I'm sure this has been asked before, but I couldn't find any straightforwards information about the subject.

I'm currently working on making a 2D game using Java2D and I'm using a simple 60fps main-timer and a paint() method with a custom double buffer, and I noticed that at certain points, especially when the computer is under load they can slow down and/or get out of sync for a short while and the results mess up the game flow.

Is there any way to prevent this by forcing graphics sync similar to a commercial game where lack of horsepower will simply lower the "fps" instead of slowing down the game?

I apologize that I couldn't formulate the question better, I'm rather new to making games. (even simple ones)
Other suggestions on how to prevent this would obviously be very welcome.

Thanks in advance. :)

Also posted on: JavaProgrammingForums.com

[doWhile]

Cross posted Force Sync on Graphics2D?

[ra4king]

It would be better if you would not use passive rendering, aka calling repaint() as I believe you're doing here. You should do all game logic and drawing in the same thread.

[Acidic]

It would be better if you would not use passive rendering, aka calling repaint() as I believe you're doing here. You should do all game logic and drawing in the same thread.

Sorry if this question is somewhat general, but how would that be done?

[ra4king]

First, you should be drawing in a java.awt.Canvas. There you can use BufferStrategy:

//init game
canvas.createBufferStrategy(2);
BufferStrategy strategy = canvas.getBufferStrategy();

//in game loop
do{
    do{
        Graphics2D g2 = (Graphics2D)strategy.getDrawGraphics();
        //drawing code
        g2.dispose();
    }while(strategy.contentsRestored());
    
    strategy.show();
}while(strategy.contentsLost());

EDIT: Make sure to disable automatic repainting on your canvas and JFrame/Applet when doing this by calling "setIgnoreRepaint(true)" on your components.

[Acidic]

First, you should be drawing in a java.awt.Canvas. There you can use BufferStrategy:

//init game
canvas.createBufferStrategy(2);
BufferStrategy strategy = canvas.getBufferStrategy();

//in game loop
do{
    do{
        Graphics2D g2 = (Graphics2D)strategy.getDrawGraphics();
        //drawing code
        g2.dispose();
    }while(strategy.contentsRestored());
    
    strategy.show();
}while(strategy.contentsLost());

EDIT: Make sure to disable automatic repainting on your canvas and JFrame/Applet when doing this by calling "setIgnoreRepaint(true)" on your components.

I've spent the last few days gathering information about the subject and your message was indeed the right direction.

Thanks a lot.