Zooming broken on Android 12

[MrPeteH]

If you'd like to put out an incentive for fixing this bug, you can do so at https://issuehunt.io/r/bk138/multivnc?tab=idle

Is your bug report about the Desktop Multivnc or the Mobile MultiVNC?

• Mobile (Android):

Which MultiVNC version are you using? 2.0.5

Which server are you connecting to?

• VNC server vendor: TightVNC
• VNC server version: 2.8.63.0
• OS version: Win10
• OS language: English

Maybe important:

• host resolution: 3840 x 1197 (two side by side screens)
• viewer resolution: 2863 x 1440 (500 dpi!)

Describe the bug MultiVNC is unusable due to large white rectangles that overlay the screen.

• On the left, top to bottom (of the viewer window... far beyond the server viewport)
• On top, left to right of the viewer window...
• If I zoom in and attempt to scroll, I also see them bottom and right

If I had to guess,

• There may be code... attempting to "frame" what I see
• But it is not done correctly. A miscalculation of viewport vs window?
• I also note that the virtual mouse is always misaligned... and the misalignment depends on the current zoom level

To Reproduce

For the Mobile Version (please complete the following information):

• Android version: 12
• Installed from Play Store

Additional context

[bk138]

Thanks for the report!

Few questions:

• Does this happen with other viewers as well? You might want to try https://github.com/gujjwal00/avnc or https://play.google.com/store/apps/details?id=com.iiordanov.freebVNC
• Does it also happen on a different viewer device (with lower resolution)? I'm asking because I might be able to reproduce a very big server screen, but probably not a high-res client...

[MrPeteH]

Does not happen on any other viewer I've tried (I've tried several, including freebVNC)

I'll work on the latter test :)

[bk138]

@MrPeteH nevermind, I can repro this on a Galaxy S10 with an example server that's set to 3840 x 1197. Does not happen with AVNC though.

[bk138]

Might be limitations of glTexImage2D, but AVNC does it similarly... :thinking:

[MrPeteH]

S10e does not have the issue. Viewer 1080x2020 at 480 dpi.

So far more a resolution than dpi thing...

[bk138]

This actually happens with every server resolution on my device now. I can state it worked before, so it's likely the recent update to Android 12 that changed something...

[bk138]

If I remove VncCanvas.scrollToAbsolute(), it works on Android 12 again. Will test with other devices the next days...

[bk138]

test results

v2.0.5

• Samsung S10e w/ Android 12: :lady_beetle:
• Samsung Tab A w/ Android 11: :ok:
• Samsung S20FE w/ Android 11: :ok:

scrollToAbsolute() removed

• Samsung S10e w/ Android 12: :ok:
• Samsung Tab A w/ Android 11: :ok:
• Samsung S20FE w/ Android 11: :ok:

[MrPeteH]

Yep. Fixed. Now I can see the next issue more clearly 🤠