[AG-TECH] VPCScreen under Linux or W7

[Harris, Chris]

Hi All

We haven't been able to get VPC to work on Windows 7 either.
Sadly our masters aren't so keen on running it on Linux.

Has anyone got it working nicely on W7, all on the same box including VPC?

Cheers, Chris

From: Jason Bell [mailto:***@cqu.edu.au]
Sent: Thursday, 5 December 2013 3:54 p.m.
To: Andrew Danson; accessgrid-***@lists.sourceforge.net
Subject: Re: [AG-TECH] VPCScreen under Linux

Andrew

This is a bug in the code - if you install an older version of VPCScreen, it will work fine.

The work around, within VPC is when the app is running, go to "File -> start". Then the button will be fine and it won't crash.

I have included some RPM's, but if you install the 0.2-5 version, it should work correctly. I am not sure where these can be found on a website.

Hope this helps.

Cheers,
Jason.


From: Andrew Danson [mailto:***@newcastle.edu.au]
Sent: Thursday, 5 December 2013 11:55 AM
To: accessgrid-***@lists.sourceforge.net<mailto:accessgrid-***@lists.sourceforge.net>
Subject: [AG-TECH] VPCScreen under Linux

Hi Guys,

Recently I've set up the AG software on a RHEL 6.4 workstation machine, and it works nicely apart from one niggling issue I've been having.
Basically VPCScreen capture software doesn't work, when you attempt to start the capture it crashes without so much as an error message.

I thought perhaps with the X servers being trimmed down significantly (specifically some extensions removed) is it possible that it simply is try to use an extension no longer in Xorg? Older programs that can capture the screen such as XV and Vic both work ok, so perhaps a rebuild is all that's required. Unfortunately Vic doesn't really have any means to control the captured area, so it's not really adequate.

If there is some source available somewhere I wouldn't mind having a hack at trying to fix it, but I've not seen any documentation about where to find the latest source (or any for that matter).

Cheers
Andrew

[Jason Bell]

Chris are you using unicast or multicast?

As you cannot use VPCScreen and have Vic transmitting at the same time, when using unicast.

Cheers,
Jason.

From: Harris, Chris [mailto:***@massey.ac.nz]
Sent: Thursday, 5 December 2013 1:20 PM
To: accessgrid-***@lists.sourceforge.net
Subject: Re: [AG-TECH] VPCScreen under Linux or W7

Hi All

We haven't been able to get VPC to work on Windows 7 either.
Sadly our masters aren't so keen on running it on Linux.

Has anyone got it working nicely on W7, all on the same box including VPC?

Cheers, Chris

From: Jason Bell [mailto:***@cqu.edu.au]
Sent: Thursday, 5 December 2013 3:54 p.m.
To: Andrew Danson; accessgrid-***@lists.sourceforge.net<mailto:accessgrid-***@lists.sourceforge.net>
Subject: Re: [AG-TECH] VPCScreen under Linux

Andrew

This is a bug in the code - if you install an older version of VPCScreen, it will work fine.

The work around, within VPC is when the app is running, go to "File -> start". Then the button will be fine and it won't crash.

I have included some RPM's, but if you install the 0.2-5 version, it should work correctly. I am not sure where these can be found on a website.

Hope this helps.

Cheers,
Jason.


From: Andrew Danson [mailto:***@newcastle.edu.au]
Sent: Thursday, 5 December 2013 11:55 AM
To: accessgrid-***@lists.sourceforge.net<mailto:accessgrid-***@lists.sourceforge.net>
Subject: [AG-TECH] VPCScreen under Linux

Hi Guys,

Recently I've set up the AG software on a RHEL 6.4 workstation machine, and it works nicely apart from one niggling issue I've been having.
Basically VPCScreen capture software doesn't work, when you attempt to start the capture it crashes without so much as an error message.

I thought perhaps with the X servers being trimmed down significantly (specifically some extensions removed) is it possible that it simply is try to use an extension no longer in Xorg? Older programs that can capture the screen such as XV and Vic both work ok, so perhaps a rebuild is all that's required. Unfortunately Vic doesn't really have any means to control the captured area, so it's not really adequate.

If there is some source available somewhere I wouldn't mind having a hack at trying to fix it, but I've not seen any documentation about where to find the latest source (or any for that matter).

Cheers
Andrew

[Harris, Chris]

Hi Jason

Sorry about the delay answering. Silly season.

Mostly we use unicast and then go through the Auckland Bridge. For Massey only meetings we often use multicast. We can't rely on multicast between universities.

It appears as though the solution may be to have a separate machine in the control of the participants running the VPC presentation, which I believe some other universities do already.

Cheers, Chris

From: Jason Bell [mailto:***@cqu.edu.au]
Sent: Thursday, 5 December 2013 4:55 p.m.
To: Harris, Chris; accessgrid-***@lists.sourceforge.net
Subject: RE: VPCScreen under Linux or W7

Chris are you using unicast or multicast?

As you cannot use VPCScreen and have Vic transmitting at the same time, when using unicast.

Cheers,
Jason.

From: Harris, Chris [mailto:***@massey.ac.nz]
Sent: Thursday, 5 December 2013 1:20 PM
To: accessgrid-***@lists.sourceforge.net
Subject: Re: [AG-TECH] VPCScreen under Linux or W7

Hi All

We haven't been able to get VPC to work on Windows 7 either.
Sadly our masters aren't so keen on running it on Linux.

Has anyone got it working nicely on W7, all on the same box including VPC?

Cheers, Chris

From: Jason Bell [mailto:***@cqu.edu.au]
Sent: Thursday, 5 December 2013 3:54 p.m.
To: Andrew Danson; accessgrid-***@lists.sourceforge.net<mailto:accessgrid-***@lists.sourceforge.net>
Subject: Re: [AG-TECH] VPCScreen under Linux

Andrew

This is a bug in the code - if you install an older version of VPCScreen, it will work fine.

The work around, within VPC is when the app is running, go to "File -> start". Then the button will be fine and it won't crash.

I have included some RPM's, but if you install the 0.2-5 version, it should work correctly. I am not sure where these can be found on a website.

Hope this helps.

Cheers,
Jason.


From: Andrew Danson [mailto:***@newcastle.edu.au]
Sent: Thursday, 5 December 2013 11:55 AM
To: accessgrid-***@lists.sourceforge.net<mailto:accessgrid-***@lists.sourceforge.net>
Subject: [AG-TECH] VPCScreen under Linux

Hi Guys,

Recently I've set up the AG software on a RHEL 6.4 workstation machine, and it works nicely apart from one niggling issue I've been having.
Basically VPCScreen capture software doesn't work, when you attempt to start the capture it crashes without so much as an error message.

I thought perhaps with the X servers being trimmed down significantly (specifically some extensions removed) is it possible that it simply is try to use an extension no longer in Xorg? Older programs that can capture the screen such as XV and Vic both work ok, so perhaps a rebuild is all that's required. Unfortunately Vic doesn't really have any means to control the captured area, so it's not really adequate.

If there is some source available somewhere I wouldn't mind having a hack at trying to fix it, but I've not seen any documentation about where to find the latest source (or any for that matter).

Cheers
Andrew

[Andrew Danson]

Hi guys,

I extracted the source code for VPCScreen, after having read it for an hour or so I think the bug under linux is fixable.

The problem stems from a bunch of variables not being initialized in vpcscreen_base_private that control the state of the vpcscreen_base class.
When the vpcscreen_base_private class is created its state variables are filled with pretty much whatever random data happened to be in RAM before being used by VPCScreen, thus causing a bunch of confusion.

In addition to fixing that by adding initialization code to the constructor for vpcscreen_base (or private) I would also want to make some of the other code a bit neater, and perhaps make it clearer which state the buttons should be in at startup. I noted the menus aren't enabled and disabled the same way the buttons are which creates potential crashes if a user clicks either one at the wrong time.

I need to set up the build environment for VPCscreen to implement and test the fix I have in mind, hopefully that won't be too hard. To be honest I'm surprised this didn't cause a more serious issue in an older version.

As for running VPCScreen on a windows 7 machine, we are running it fine here on one of our machines, and use it on a regular basis. What kind of symptom are you getting? A crash? The start button greyed out (like the linux bug)? You can run VPCScreen separately from the AG software via the command line much like you can with vic, that will print errors out on the console that may help. Otherwise the AG log would be a nice place to look.

You can run Vic and VPCScreen at the same time for transmitting on unicast, I've done it on numerous occasions on windows XP. The technical reason for this is due to how UDP works (the transport mechanism used in the AG with unicast). It _should_ work on most other Os's as well.
Cheers
Andrew