[solved?] X server screwed up by LWJGL

[thygrrrr]

EDIT:
I have found a workaround, uncommenting the following lines in my xorg.conf

Section "Device"
        Identifier  "aticonfig-Device[0]"
        Driver      "fglrx"
#       Option      "VideoOverlay" "off"
#       Option      "OpenGLOverlay" "on"
EndSection

I still wonder, however, where exactly the problem lies now.




Hello!

I have the a problem with LWJGL on Kubuntu 6.06 with Xorg 7.0.0, ATI fglrx Drivers 8.25.18 to 8.29.x, kernel 2.6.15.23-686 to 2.6.15.27-686, Sun Java 1.5.0 U9 or Java 1.6.0 Beta ... I have a VIA Chipset Shuttle SS-51G XPC with a P4 2.4 Ghz, an ATI Radeon X1600 (reference design) and 1GB of RAM. Most non-lwjgl 3D-apps run fine under linux and windows alike. LWJGL stuff seems to be the exception.

The Problem:
The apps (e.g. demos and tests) run fine (displaying, minimizing, moving to desktop etc), but AFTER or UPON closing them, the whole X system is instantly borked: The LWJGL window closes, and then shortly afterwards the display freezes and only a few parts of the screen update, usually some context menus, window borders, and text fields; the rest is frozen. The mouse pointer is still there and works/reacts fine, you can drag stuff around on the desktop and all, but it's not shown on the screen apart from the changing mouse cursor. Everything still responds internally(e.g. I can send IMs or type in the shell blindly and stuff is executed)

No java processes are left running. The only remedy is killing and restarting the X server.

The error does not occur with the mesa software drivers.

[darkprophet]

try doing:

sudo apt-get install xmoto-data xmoto

then running XMoto from the Games section. That game (besides being bloody awsome) uses OpenGL and should tell the LWJGL team whether its a driver/kernel/chipset problem, or a LWJGL problem..

Also, do you run your app in fullscreen mode or not ?

DP

[thygrrrr]

Windowed. Switching a windowed app to fullscreen makes the server die as well.

How exactly would that game help me? There's no error/crash/core dump/whatever. The app terminates fine, except that something, somewhere messes up the graphics context.

[thygrrrr]

Ooooook. xmoto runs and terminates fine. This strikes me as odd, but leaves some room for hope.

The GL demos from the lwjgl site don't. They either start and then don't terminate properly as described, or they don't even start and then cause the same freezing/corrupted display symptoms.

Example for one that runs: GLgears.
Example for one that crashes: PbufferTest

The CreateWindowTest does it, as well.

Any clues? I'll try to get the output from one of the demos that crashes. If I figure out how to capture JNLP stdout ...

[darkprophet]

The reason I chose that game is because it uses OGL and is a native application. I wanted to narrow the causes down from being a potential driver/kernel thing to being a specific LWJGL issue that the developers should be looking at.

Personally, i have Ubuntu 6.06 working fine over here albeit on a K7 kernel and an nForce chipset and an nvidia gfx with nvidia drivers, so I dont know about your problem to be honest...

The mesa software drivers are...software. So there is no driver/kernel (maybe a little kernel) stuff going on.

DP

[thygrrrr]

Oh ok so xmoto isn't LWJGL at all... duh. I thought I said clearly enough that "most 3D-Applications run fine" and LWJGL is the exception, hehe!

Thanks for trying, though So actually I don't have any more info (except that lwjgl does work on another person's ubuntu).


Which drivers do you use? I moved back from a semi-recent one after problems with the neweste one to the driver that comes with kubuntu. Which kernel do you boot? Which version of Java do you use?

[thygrrrr]

Update: The problem persists if Display.destroy() is not called during application shutdown. I'm down to wildly guessing; that's why I tried it.

I'm one step short of putting my old NVidia Graphics Card in and see what happens. However, that's quite a bit of work, both mechanically (extremely crammed barebone case) and on the driver setup side, so I would love to get around it.

[elias]

I don't know what would cause this. It's definitely _also_ a driver/X/kernel problem since no program should be able to crash the system that way. However, that won't help you of course, so here's what you could try:

1. Try cutting the amount of work done in the test program to the very minimum. For example, does main() {Display.create(); System.exit(0)} crash the system?
2. Try AWTGLCanvas and see if that crashes too. (You can try the org.lwjgl.test.opengl.awt.AWTGears test if you want, pruning it as much as possible.

However, if even the minimal test cases crash the system, I can't really help you much, without having access to your setup. You could try pruning LWJGL itself systematically until the very minimum is left, but that's harder than just cutting your own stuff.

- elias

[thygrrrr]

See first post

Strange, strange.