Flickering Java GUI in Ubuntu 14.04

问题

I stumbled upon a problem I cant solve nor can I understand. I'm writing a simple 2D game using Java 1.8.0_31 with java.awt.Canvas on Ubuntu 14.04. The problem is that I get this unbearable flickering(an issue I never had on Windows), to make sure my code is not the problem I wrote a small test program with a moving circle...

The test loop:

public void run() {

    long startTime = System.currentTimeMillis();
    long tick = 1000;
    int fps = 0;
    int upd = 0;

    double nanoScale = 1000000000.0 / 60;
    double delta = 0;

    long lastTime = System.nanoTime();
    while (running) {

        long now = System.nanoTime();
        delta += (System.nanoTime() - lastTime) / nanoScale;
        lastTime = now;

        while (delta > 1) {
            update();
            upd++;
            delta--;
        }
        render();
        fps++;

        if (System.currentTimeMillis() - startTime > tick) {
            window.setTitle(title + " || Fps: " + fps + " | Upd: " + upd);
            fps = 0;
            upd = 0;
            tick += 1000;
        }

        try {
            Thread.sleep(5);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }

}

This gives me a nice and steady Update rate of 60 with a 185-190 fps rate which is only limited by the Thread.sleep(5) call.

However it looks/feels like the fps is incredibly low(as though as most frames get dropped), now before you start yelling use multiple buffers...

The render method:

public void render() {
    BufferStrategy bs = getBufferStrategy();
    if (bs == null) {
        createBufferStrategy(3);
        return;
    }

    Graphics2D g2d = (Graphics2D) bs.getDrawGraphics().create();
    g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
    g2d.setColor(Color.black);
    g2d.fillRect(0, 0, getWidth(), getHeight());
    g2d.setColor(Color.red);
    g2d.fillOval(x, y, 10, 10);
    g2d.dispose();

    bs.show();
}

Oddly enough enabling the antialising hint greatly reduces the flickering but not removes it.

I cant see the relation between the problem and antialiasing, enlighten me if there is a connection(I always got a clean and smooth result on Windows regardless of antialiasing).

So I guess the question is:

What might cause the issue described and what can be done about it?

Just in case this helps my Graphics card is gtx770 and I'm using the NVIDIA binary driver - version 340.76 from nvidia-340(open source)

来源：https://stackoverflow.com/questions/28438715/flickering-java-gui-in-ubuntu-14-04

标签

java

Ubuntu

graphics

flicker