Resize scratch window, it doesn't update, goes black, and shrinks to a vertical strip in Unity-3D.

[Alan Pope 🍺🐧🐱 🦄]

Open scratch in a unity-3D session
Maximise the window
Observe the window goes black and the app is unusable.
Unmaximize the window
The window shrinks to a small strip.

Only happen when run in unity 3D.
Does not happen when the image file is manually opened with squeak.
Does not happen when the -xshm switch is removed

See screenshots.
Video: http://youtu.be/bpTX7O3NDy4

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: scratch 1.4.0.6~dfsg1-2~ubuntu12.04.1
ProcVersionSignature: Ubuntu 3.2.0-26.41-generic 3.2.19
Uname: Linux 3.2.0-26-generic x86_64
ApportVersion: 2.0.1-0ubuntu8
Architecture: amd64
Date: Sun Jul 15 19:38:13 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
PackageArchitecture: all
SourcePackage: scratch
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[linux-man (caldas-lopes)]

Stranger than that: After resizing, non-maximized black scratch window start "shrinking" horizontally until turns to a vertical line!
Updated Ubuntu 12.04 64 using revamped Unity

[Greemod (gree-w)]

I did some troubleshooting and found that if I right-click on the .image file and click open-with squeak there are no problems resizing the window, but full screen mode does not work. I was able to save the image in a proper windows size.

[Amos Blanton (lightnin9)]

We did some testing and found that this bug does not happen when running in 2d mode.

[Greemod (gree-w)]

This bug does not happen when run in a GNOME session. Seems to only happen in unity-3D

[Greemod (gree-w)]

I figured it out! I removed the vm option -xshm and now it resizes fine.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "black_screen.patch" of this bug report has been identified as being a patch. The ubuntu-reviewers team has been subscribed to the bug report so that they can review the patch. In the event that this is in fact not a patch you can resolve this situation by removing the tag 'patch' from the bug report and editing the attachment so that it is not flagged as a patch. Additionally, if you are member of the ubuntu-reviewers team please also unsubscribe the team from this bug report.

[This is an automated message performed by a Launchpad user owned by Brian Murray. Please contact him regarding any issues with the action taken in this bug report.]

[Amos Blanton (lightnin9)]

That's great! Here's the functionality of that command line switch:
"-xshm
enables the use of the X Shared Memory extension on servers that support it. This can dramatically improve display performance, but works only when Squeak is running on the server."

http://www.squeakvm.org/unix/doc/squeak.html

So we should verify that there's no performance loss as a result of removing that switch. I'll try to do some testing soon.

[Amos Blanton (lightnin9)]

Awesome - I can confirm that removal of the switch mentioned above does make window resizing work properly in 3d mode. And after testing several projects, performance does not appear to be affected. :)

Anyone have any insight into why the removal of that switch makes things work?

[Greemod (gree-w)]

When will a new version with this fixed be released?

[David G. Johnson (n-david-johnson)]

Please forgive the neophyte question, but is it possible for me to apply Greemod's patch to my current Scratch installation on Ubuntu Ubuntu 12.04?

[Daniel van Vugt (vanvugt)]

Greemod:

Please propose your fix for merging into lp:scratch.

[Mario Guerriero (mefrio-g)]

Greemod follow Daniel's suggestion and I will merge your patch in lp:scratch.

[Amos Blanton (lightnin9)]

Hi David:

Here's a fix. In a terminal, type:

sudo gedit /usr/bin/scratch

You'll see a line that starts with VMOPTIONS. Remove the -xshm from that line, so it looks like this:

VMOPTIONS="-encoding UTF-8 -vm-display-x11 -plugins /usr/lib/scratch/plugins/:$SQ_DIR/"

Save the file. Scratch should no longer have this bug.

[Amos Blanton (lightnin9)]

I've made an edit to the debian scratch repository, here:

https://alioth.debian.org/projects/pkg-squeak/

After some testing, they should submit an update containing this and other fixes soon.

[j.schirmacher (j-schirmacher)]

The same Problem on a new installed Ubuntu 12.10 system with Unity standard.

Some more hints: wrong window size and wrong launcher items (Squeak instead of scratch)

[Bruce Pieterse (octoquad)]

I can confirm that removing the -xshm option from /usr/bin/scratch resolves the problem. The switch -xshm seems to work fine in 3D mode (unity) on a secondary screen though. See attachment in bug #1072309

[Alex Eftimie (alexeftimie)]

This is still a problem, please merge that patch.

I'm teaching a course for kids using Scratch, and I have to apply the patch manually on every ubuntu installation - or else, no window resize is posible.

[Jeremy Bícha (jbicha)]

scratch (1.4.0.6~dfsg1-3) unstable; urgency=low

  [ Miriam Ruiz ]
  * Added support for help in starting script. Thanks to Alec Clews.
  * Changed my email to <email address hidden>

  [ Amos Blanton ]
  * Prefer pulse plugin if pulse is present, because pulse ALSA emulation
    fails when user records sounds.
  * Remove -xshm switch to squeakvm to prevent Ubuntu Bug 1025013.

[Rolf Leggewie (r0lf)]

quantal has seen the end of its life and is no longer receiving any updates. Marking the quantal task for this ticket as "Won't Fix".

[Steve Langasek (vorlon)]

The Precise Pangolin has reached end of life, so this bug will not be fixed for that release