Java Swing性能OS X 10.6与Windows 7

Question

This is my first post to this forum, I have about 6 months of experience of Java in general, and about 1 month of Java GUI programming (Swing), so consider me as a Java newbie.

I started to develop a simple 2D shooter game with Java swing as a hobby project. I am using Java 1.6.0_65 with Mac OS X 10.6.8, Macbook Pro 2.4 GHz Intel Core 2 Duo (Spring 2010 model), the display card is NVIDIA GeForce 320M.

In my paint method, I draw about 30-50 rectangles with Swing drawRect() method, sizes of 32 * 32 pixels, few are of 7 * 7 pixels of size, the smaller ones are filled with fillRect . I call the paintComponent() method 50 times/sec from a timer callback.

To get some kind of idea of how fast/slow the painting is, I added some measurement code, to record starting and end times of paintComponent() method, and calculate the average duration, using System.nanoTime() method.

Average execution time per single paintComponent() seems to be about 3000 usec on OS X 10.6.

I also run same code in couple for Windows 7 PCs (Sony Vaio laptop, AMD dual core 2.x GHz and HP laptop, Intel quad core, 2.x GHz, don't remember all details now). In Windows machines, average execution time was only about 100 us, that is about 30 x faster!

What can explain such a big difference? Can System.nanoTime() work with different resolutions between Windows 7 & OS X, or is painting really that slow in OS X?

On the other hand, I also measured average execution time of the non-GUI related part of my game engine (moving of objects, collision detections etc.), and it was between 50 - 100 us on both system, so maybe System.nanoTime() is reliable, and painting really is that slow in OS X?

Edit: I am unable to copy-paste any code here from xCode and Eclipse, I keep getting complains about formatting, but you can look a test app I wrote to illustrate this problem, at: http://www.java-gaming.org/topics/swing-performance-os-x-10-6-vs-windows-7/31654/view.html .

I am getting quite slow performance on Mac also with this test app, about 1400 - 1800 usec / paint operation.

Answer 1

I have the same issue with SWT on Mac. Another observation is that on Mac, as opposed to Windows, there is never any flicker, even without double buffering. That may or may not indicate that the underlying reason for the weak performance is in added safety of operations (they may block until a vertical refresh, to avoid flicker).

Answer 2

It appears the rendering on MacOS X for built in Intel graphics based Retina displays is slow. This is highlighted in this JDK bug comment . It is resolved in JDK 8 patch 40 (8u40).

I bumped into this as well whilst creating a 2D side/vertical scrolling game and am investigating the rendering on Mac:

• Yosemite 10.10.3
• MacBook Pro (Retina Mid 2012)
• Processor 2.7Ghz Intel Core i7
• Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716)

I am performing my rendering via the standard JComponent#paintComponent(Graphics) approach and using my own rolled double buffering approach so I can isolate the time spent preparing the image versus the time spent actually drawing the image with the single call to Graphics#drawImage() to the display device.

If I use the MBP's built in display ( Intel HD Graphics 4000 ) to draw an image 1680x1500, it takes 30ms to complete this.

If I then switch to the external display ( NVIDIA GeForce GT 650M ), for the same code and same image size I get a time of 5ms .