Strange graphics behaviour in VASL main window

[bprobst]

Has anyone else noticed the following? It's been happening to me for about six months now, or maybe more.

PC: Windows 10, 64-bit. AMD-based graphics card.

I was running VASL on this PC for several months with no problems at all. Then, one day, I started noticing peculiar things happening in the VASL main window: the text would get "garbled", randomly scrolling and relocating to portions of the window that it shouldn't be -- so buttons get overwritten with random chunks of text from the log, etc. The window becomes virtually unreadable.

Other VASL windows not affected at all (thank goodness). And if I hover the mouse over where a button should be, the button becomes visible, and works correctly. So I can continue playing the game OK, it's annoying rather than disastrous. New entries in the window appear correctly so I can see and read them, but before too long the random scrolling and over-writing affects them too. It's purely local to me, it has no impact on my opponent.

It doesn't start happening until after I've been playing for a little while (say 30 minutes or so). Once it starts it keeps happening for the rest of the game. If I close VASL/VASSAL and restart it, all is good for a while (until it happens again). Since I first noticed this problem, I've never seen it not happen during any session of meaningful duration -- it appears to be inevitable.

Now, clearly, since it never used to happen at all, it must be the result of some system update. It must be something in my Windows environment, and not as a result of any change in the VASSAL/VASL environment (since there were no such changes). To me that points the finger at either the video drivers or Java, both of which have been updated many times. I'm not super interested in regressing either of those, especially since the problem is purely "visual" and I can work around it. I could cope with running an older version of Java, I guess, if I knew for certain that it was the culprit.

I would be curious to know, if anyone can explain, why such an issue would affect only the VASL main window, and nothing else. (If it affected the map window I'd be thoroughly screwed.) Something that occurs to me is that the main window is mostly text-based, whereas other windows are more image-oriented. And yet the server connection window is not affected, and so far as I can tell it's entirely text-based. And there are images in the main window. Any thoughts?

 

[uckelman]

I can confirm for you that it's not VASL or VASSAL doing this. My best guess is that it's Java, but I wouldn't be surprised if it were a buggy video driver as well.

 

[clubby]

It sounds like a bad video card problem rather than a software issue.

 

[jrv]

It sounds like a bad video card problem rather than a software issue.

If the problem is happening in only one application window and consistently in that window only, it is unlikely to be something the video card would know about. Video cards, so far as I know, don't know anything about windows (as in separate rectangles on the screen, not the os, although they probably don't know much about either). You might test the hypothesis by changing graphics mode to a lower resolution to see if the problem changes in some way. More likely suspects are the areas of the computer that are aware of windows, which would be java, the os, and the graphics library. It sounds as though something is writing in memory it should not be writing into.

JR

 

[clubby]

I said it sounds like a video card issue. Abnormal video behavior in my past many, many years of experience building and maintaining many computers is that random erratic video behavior is typically the card or the power supply. I mean we're just throwing out some possible culprits based on a pretty limited amount of initial data.

 

[Michael R]

I can't offer any insight to your problem, but I can report something similar occurring on my MacBook laptop (but not on my iMac). I use separate VASL windows. The VASL Controls window sometimes overwrites a line of text instead of bumping the line up the window. It is a recurring, but intermittent problem. It affects only the text in that window.

 

[bprobst]

It sounds like a bad video card problem rather than a software issue.

Uh, no, that could not possibly be true. What you're suggesting is that the VASL main window calls on a specific area of video card memory, and ONLY that single area, and no other software in Windows ever uses that particular section of memory. Furthermore, it would require that VASL ignore the OS and write instructions directly to the video card.

It's not "random behaviour". It's very specific behaviour and consistently reproducable.

(FWIW, I also have many, many years of building and maintaining PCs.)

 

[bprobst]

I seem to recall reading somewhere that the main window in VASL is actually a specific VASSAL system object (that's customised for VASL requirements, obviously) -- i.e., every VASSAL game has a "main window". If I'm correct in that presumption, then it's probably the <system interaction with VASSAL> at fault, not the <system interaction with VASL>. I guess the easy way to test that would be to run some other VASSAL modules and see if the same behaviour occurs with them. Note that I'm not saying that I think VASSAL is the problem, rather that I think it's VASSAL that demonstrates the problem that lies elsewhere in my system (but doesn't seem to bother anything other than VASSAL).

I posted the query really to see how widespread the issue might be and to see if I could get an explanation of what's so special/different about the main window compared to other VASSAL/VASL windows.

Michael R.'s comment about a very similar issue occurring on a MacBook but not an iMac seems to suggest that it's more likely to be driver-related than Java-related, but I know very little about Mac hardware etc.

 

[zgrose]

A screenshot would be handy. Have never seen anything like it myself.

 

[bprobst]

Curious follow-up. I played a VASL session yesterday for several hours (and I was keeping an eye out in order to grab a screenshot) and the problem did not show up at all. I seem to recall a fairly recent Java update, perhaps they've resolved whatever the issue was. I'll keep my fingers crossed, but a sample of one is not conclusive of course.

 

[jrv]

I'll keep my fingers crossed, but a sample of one is not conclusive of course.

A sample of N is not conclusive, unless there are exactly N items, and you have picked without repeats.

A java problem sounds very plausible given the symptoms you were experiencing.

JR

 

[Michael R]

Here is a screen shot of the error that I mentioned, which is not exactly the same as what Bruce reported.

 

[bprobst]

And yet more developments.

During a VASL session that I was playing last night, the graphical problem asserted itself as usual -- so, clearly, my initial hope that it had been resolved was false. Sorry, I forgot to take a screen shot.

What was different this time is that shortly afterwards the graphics "reset" -- i.e., the visual problem disappeared and all was behaving correctly again in the main window, for the remainder of that session. I've never seen it do that before.

I think this is the point where I throw up my hands and say "whatever".

 

[uckelman]

The problem you're seeing is called "tearing". The code which handles painting of GUI elements isn't ours---it's part of Java. The bug is in some combination of Java, your video driver, or your OS.

I've seen tearing sometimes on Linux as well, which suggests that the problem is in Java.

 

[Blackcloud6]

I've had this happen now and then too. It can cause the dice buttons to get all messed up. The quick fix is to minimize the window and bring it back.

 

[sasharp65]

I'm having this same issue. Win10 - x64 - AMD graphics card.

Has anyone figured out the issue?

I have latest Java and Vid Card Drivers.

Thanks

 

[TopT]

I am having a different type of issue. When I hit the LOS button, not all of my units "disappear". i will have anywhere from 3 to a slew of my units still left on the board. It makes it tough to truly get a good LOS.

Win7, 8 Meg Ram, Nvidia GeForce GT 520 & latest JAVA & Vid cards

 

[bprobst]

Has anyone figured out the issue?

It's probably a combination of recent versions of Java and recent drivers for AMD-based video cards. VASL is the only JAVA-based software that I run, and I never see the issue appear in any other application. Possibly it's unique to Windows versions of JAVA and the video drivers, I don't know. It might only crop up in relatively high-end AMD-based video cards (as opposed to older/cheaper versions).

If someone who is experiencing the problem is in a position to either swap out their video card for one that's not AMD-based, or use their current hardware to run a non-Windows OS, then that might be a useful test. Regardless, though, I don't think you can actually do anything about it (other than replace your PC with something completely different). I'm just resigned to put up with it. Minimising the affected window and restoring it is quick and simple enough to not disrupt the game.

A more serious problem is when my map window keeps repainting, over and over. I don't know if this is a related bug or a completely separate one. When it does happen, it is enough to disrupt the game -- I have to close VASL/VASSAL completely and restart it, because interacting with the map becomes literally impossible. Fortunately it's only something that happens occasionally, unlike the text corruption.

(One thing I changed recently was to update my version of Java to the 64-bit version instead of the 32-bit version I had been using. It didn't resolve any of the bugs, unfortunately, but it did provide a minor performance boost to VASL on my PC.)

 

[von Marwitz]

A more serious problem is when my map window keeps repainting, over and over. I don't know if this is a related bug or a completely separate one. When it does happen, it is enough to disrupt the game -- I have to close VASL/VASSAL completely and restart it, because interacting with the map becomes literally impossible. Fortunately it's only something that happens occasionally, unlike the text corruption.

I have recently experienced the same issue as well (I am using VASSAL v3.2.17 and still VASL v6.3.3). However, the 'map' in question was a massive affair using roughly 20 geo-boards. I tried to resync without amends. Because the map area was so large, I suspected that it might be some sort of 'overflow' as VASL might not expect so many geoboards used simultaneously.

This is, however, the only instance I ever came across this phenomenon. And I do not know which versions of VASSAL/VASL the person used who had created the map (It was Tom Arnold from Australia).

von Marwitz

 

[uckelman]

I have recently experienced the same issue as well (I am using VASSAL v3.2.17 and still VASL v6.3.3). However, the 'map' in question was a massive affair using roughly 20 geo-boards. I tried to resync without amends. Because the map area was so large, I suspected that it might be some sort of 'overflow' as VASL might not expect so many geoboards used simultaneously.

This is, however, the only instance I ever came across this phenomenon. And I do not know which versions of VASSAL/VASL the person used who had created the map (It was Tom Arnold from Australia).

von Marwitz

Constant repainting is caused by images loading and filling the tile cache before painting finishes, which causes the images to be reloaded, once again filling the tile cache... The solution is to increase your max heap size.