uVNC not refreshing screen

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ffredyk
Posts: 3
Joined: 2022-10-05 13:15

uVNC not refreshing screen

Post by ffredyk »

Hello,

we are using uVNC to connect to a device running a proprietary Java software. The software changes information on screen each second, but uVNC won't show these changes until some kind of user interaction (window handle moving, minimalizing, maximalizing, opening start menu) happens. It just shows the same screen without any updated pixels..

We tried using Poll Full Screen function, which solved the issue temporarily until we restarted the machine. Settings was stored, but the function behaved like it was disabled after the restart - settings dialog showed enabled options though

https://i.imgur.com/lteAZIE.png

Is this some kind of issue in uVNC? Are we doing something wrong? What can we do to solve this issue?
Thanks for all responses
Rudi De Vos
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Re: uVNC not refreshing screen

Post by Rudi De Vos »

OS version/ vnc version

Check the saved options in the ultravnc.ini file

[poll]
TurboMode=1
PollUnderCursor=0
PollForeground=0
PollFullScreen=1
OnlyPollConsole=0
OnlyPollOnEvent=0
MaxCpu2=100

set this to force polling, polling is disabled when the driver is used
EnableDriver=0
EnableHook=1
ffredyk
Posts: 3
Joined: 2022-10-05 13:15

Re: uVNC not refreshing screen

Post by ffredyk »

Win 10 Ent / latest uVNC (1.3.8.1)

Everything is saved, behaviour is still the same. We figured out that to make it work after restart, we just have to open the settings dialog and confirm it, that activates the polling even though no change was made in the dialog. Poll settings are enabled and persistent both in the dialog and in the file, it just seems that whatever is supposed to activate the polling on start of the application - doesn't work.
Rudi De Vos
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Re: uVNC not refreshing screen

Post by Rudi De Vos »

This are my settings

Image
Sander02
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Re: uVNC not refreshing screen

Post by Sander02 »

This behavior we are seeing on a lot of remote machines, but not java program related. Just all windows/desktop.
viewtopic.php?p=111149#p111149
Sander02
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Re: uVNC not refreshing screen

Post by Sander02 »

@Rudi, My max cpu setting is also 100, but in the ini file it is 40.
What does de DDEgine engine? This is not a default setting right?
Rudi De Vos
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Re: uVNC not refreshing screen

Post by Rudi De Vos »

I have been testing the clipboard and refreshing but without luck for now.

ddengine: ( windows 10 )
This is actual MS replacement for the mirror driver.
The ddengine capture the screen including directx and all other special screen stuff.
The ddengine also provide a list of all screen rects that were changed.
This result in a fast and responsive screen, even faster then using a driver <<win7

https://learn.microsoft.com/en-us/windo ... op-dup-api
ffredyk
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Re: uVNC not refreshing screen

Post by ffredyk »

Wouldn't ddengine solution be flagged by antivirus software? D3D was one of the major screen capturing solutions for malicious software and I think that our AV flags everything touching directx dlls to capture screen. That's one of the reasons we can use UVNC in our corporate environment, as it wasn't getting flagged by AV. And we cannot change AV exceptions as it is managed on a higher corporate level.
Rudi De Vos
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Re: uVNC not refreshing screen

Post by Rudi De Vos »

ddengine is a pure user mode solution, no admin access required, it isn't a driver.
D3D realy hooked in directX, hard to maintain and caused a lot of trouble, never used that method.

I din't expect an AV to flag aapi call provided by Microsoft.
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