I created a Java program that generates user-driven animations, allowing real-time adjustments while the preview plays. I'm using javax.swing.Timer to refresh the animation every 20 ms. On Windows, it generally updates around every 30 ms, which I can deal with, but on Linux, it drags to about 80-100 ms! I'm not sure how to troubleshoot this. I've since mostly resolved the issue to about 30 ms on both OSes after some tweaking, but I'm still curious about potential optimizations. Additionally, the performance seems to drop when the window is maximized, likely due to scaling the animation based on the window size. Any tips?
3 Answers
It sounds like the javax.swing.Timer might not be the best choice for timing animations, no matter the OS. To start troubleshooting, I suggest creating a test program to check the timer's resolution. Also, gather some info on your CPU usage and threading. For better performance, consider using a different timing method instead of javax.swing.Timer especially for animations. It’s worth looking into Java's animation frameworks or even using a separate thread for smoother performance.
If you're looking for a better timing mechanism, you might want to explore using the ScheduledExecutorService or even a game loop approach for animations. These can offer finer control over animation timing.
Maximizing the window can really slow things down, especially with Swing which isn’t optimized for heavy graphical rendering. You’re on the right track considering optimizations. Specifically, it might help to limit the area being redrawn or improve your drawing routines to focus on just what changes each frame.
It seems the drawing takes ages when rendering an image over animations. The drawing code for BufferedImage itself is quick, but the actual rendering is slow. I tried pre-scaling it for optimization, but it didn’t help and I rolled that back. Any suggestions on speeding up the `g.drawImage()` function?
Make sure you’re using a compatible image with the GraphicsConfiguration, as that can significantly impact draw times. You might also want to look into using hardware acceleration if your setup supports it!
The sluggish performance might be linked to the Java Virtual Machine. Debugging this can be tricky since Java's performance can vary significantly across different setups. Keep an eye on the JVM settings related to performance also could help optimize things.
I ran a small test after your suggestion. On Windows, the timer averaged about 15-16 ms, while Linux stayed around 1 ms. My program mainly runs single-threaded with some tasks offloaded for saving/loading. Under Linux, it puts a 5-6% load on the CPU. I'm using Linux Mint with the latest OpenJDK. Any recommendations on alternatives to javax.swing.Timer?