Strange rendering bug (Netbeans 6.5, Ubuntu 8.10)

[ako]

Hi,
I discovered a strange rendering bug when opening big PHP files.
The first 500 or so lines are displayed like this (see attachement), everything below gets rendered normal.
It seems that the pane is not properly refreshed? It happens when you scroll through the code.
This appeares from Netbeans Versions 6.5rc1 to 6.5.
I'm using Ubuntu 8.10 with Java build 1.6.0_10-b33.

But it seems to be a generic Java bug, because all of a sudden the Zend Studio IDE (which I used before Netbeans) showed similar symptoms.
(I couldn't reproduce it with Eclipse though).
Has anybody seen this effect yet?

[Petr Pisl]

Hi,

I haven't seen this before yet. Do you have Compiz switch on?

Regards,
Petr

[ako]

No, I don't have compiz enabled...

[Jan Chalupa]

Also please verify that NetBeans is really using the JDK version you
mention. Other JDK alternatives available in Ubuntu may cause rendering
problems.

You can check the JDK version in Help | About.

-Jan

Petr Pisl wrote:

[ako]

[Petr Pisl]

Thanks for the info. So the problem will not be in the version of java.

I haven't seen or heard about this yet. Do you know about someone else,
who has similar problem? I'm afraid that the issue will be somewhere in
combination java + driver + xXwindow. But this is just my guess.

Regards,
Petr

[Jan Chalupa]

Petr Pisl wrote:

[ako]

The only other person that I know, who uses Netbeans with the same PHP sources is running it on OSX, he doesn't have these problems.
I'm running it on a three year old notebook with a i810 (Intel) onboard chipset.
But I will get a new notebook in the next weeks, I will check if the problem persists there!
Thanks so far.

[Micel]

Hi !

I have the same problem im running Ubuntu 8.10 x64 + 1.6.0_10; Java HotSpot(TM) 64-Bit Server VM 11.0-b15 + NetBeans IDE 6.5 (Build 200811100001) on a Dell OPTIPLEX 745

it happens when i scroll any .java file in the editor

[Jan Chalupa]

Thank you for the report.

[ako]

[Jan Chalupa]

ako wrote:

[ako]

[Jan Chalupa]

Thanks. I've filed an internal bug report #6776352 against JDK. If
accepted, it should show up on the public bugs.sun.com site in a couple
days. The responsible engineer may ask for more info, so stay tuned.

There's one more thing you could try in the meantime. It might be worth
trying the previous JDK release - 6u7. There's a slight chance this
issue is a regression introduced in 6u10. If you're still willing to do
a little bit of experimenting, go to

http://java.sun.com/products/archive/j2se/6u7/index.html

Download the JDK 6u7 for Linux (the plain .bin package, not rpm),
install it, and try the simple Notepad experiment with this version. If
it doesn't help, you can just delete the installation. It won't replace
the default 6u10 you already have.

Thanks again,
-Honza


ako wrote:

[Jan Chalupa]

So, we've got the initial evaluation from the Java2d experts (full text
pasted below) and as expected, they're looking for more info.

Specifically:

1. It would be nice, if someone experiencing this problem could also
test with JDK 6u7 and report back the results. (I sent the instructions
on how to install 6u7 earlier in this thread).

2. The reports we've seen so far were for Ubuntu 8.10. Anyone
experiencing this with Ubuntu 8.04 or other Linux systems? Anyone able
to test both 8.10 and 8.04 on the same HW?

3. As requested by the JDK folks, it would be nice to get the following
files from the affected systems:

* /var/log/Xorg.0.log
* /etc/X11/xorg.conf

(You can email them to me directly. No need to attach them to this thread.)

4. A help of someone willing to go through the instructions in the
Java2d troubleshooting guide mentioned below and report the results
would be highly appreciated.

Just note that to pass properties to the JVM, you need to prefix them
with '-J' when starting NetBeans, i.e.:

./netbeans -J-Dsun.java2d.pmoffscreen=false

The environment variables should work without extra tricks.

Thanks,
-Honza


-------------------------------%<------------------------------
This doesn't look like a problem with the text rendering. It looks like
the Swing back-buffer isn't cleared before being repainted, so text is
painted over the old text.

However although I created a similarly sized set of content for Notepad
as shown in the attachment. I can't reproduce it, at least under vmware,
which is the only access I have to Ubuntu 8.10.

We need a whole lot of info here :

Is there a precise set of steps to reproduce ?

- Please confirm that this is
1) 6u10 only, not 6u7 ?
2) Ubuntu 8.10 only, not Ubuntu 8.04 ?

It could well be a bug in Ubuntu 8.10, perhaps specific to the driver.
It would be helpful to have the
* /var/log/Xorg.0.log
* /etc/X11/xorg.conf
from both systems attached to this report.

And please have those who can reproduce it try the troubleshooting tips
at
http://java.sun.com/javase/6/webnotes/trouble/TSG-Desktop/html/java2d.html#gcghm

More specifically, does the problem manifest if any of the following
steps are made:
1. disable the use of pixmaps: pass property to the application:
-Dsun.java2d.pmoffscreen=false
2. diable the use of shared memory pixmaps: set this env. variable:
J2D_PIXMAPS=server
3. disable the use of shared memory: set this env. variable:
J2D_USE_MITSHM=false

Report back the results.
-------------------------------%<------------------------------



Jan Chalupa wrote: