Wrong resolution on external Display (1920x1080 landscape)

[5A52]

Describe the bug
Runing droidVNC-NG on external display reports wrong resolution to viewer

To Reproduce
Needs external monitor

Ill try to explain with screenshots.
Screenshots are from RVNC on another android phone because RVNC reports server resolution, but behavior is the same on any viewer, even on PC

Viewer in portrait mode

Viewer in landscape

Viewer with server resolution

Different VNC server for android
No idea why it scales down resolution (both, client and server are FullHD) but aspect ratio is correct.

P.S. Input works, but sends touches to main phone display

[bk138]

Thanks for reporting!
Two thoughts:

• Have you tried with another viewer?
• Is this something that can be reproduced with an emulator? How is the screen attached?

[5A52]

1 - yes, bVnc on android and reminna arch on a PC. I mentionned up there, screenshotst are from RVNC only because RVNC reports server resolution.
2 - I believe yes, if emulator emulates "secondary displays". It is also possible to simulate it from android Developer options, but simulating on a main display is a real mess.
My screen is a HDMI attached to samsung note 9 phone.

[bk138]

I don't have an MHL cable so if ever can only repro this w/ the emulator. Detailed steps of how one is able to reproduce this w/ the emulator would help a lot!

[5A52]

Sorry Im not using emulator, unfortunatelly not a developer at all, but may be this will help:
https://innovorder.dev/multi-screen-management-within-android-56ef9052f066
or this
https://source.android.com/docs/setup/create/cuttlefish-multi-display
Also I dont know how droidVNC-NG code gets display resolution/aspect ratio/etc, but I can provide any logs or other information from a physical hardware if you need. Like for example android reports my displays as:

#wm size -d 0
Physical size: 1440x2960
#wm size -d 2
Physical size: 1920x1080

And here is some ifo about input methods:
https://source.android.com/docs/core/display/multi_display/ime-support

[bk138]

Maybe you can try and download Android Studio which includes an emulator and try to reproduce. I can't fix this as I don't have the MHL/HDMI hardware and need another reproduce case.

[5A52]

Sorry, I can not install android studio on an android phone (im using a phone as a kind of desktopPC). I believe you will easely reproduce the bug with emulator, chose landscape aspect ratio for secondary display.
Detailed steps in the first link are:

Click on the 3 dots in the toolbar to open Extended Controls
Choose Displays on the vertical menu
Click on the button Add secondary display
You could choose a pre-defined resolution or set a custom one (1920x1080 or 960x540 here)
Click on Apply Changes

As I mentioned on 4th screenshot "Alpha VNC Lite" which is Android VNC server also, does not have this bug.

[RaulMerelli]

I'm not using an external Display, but I have some resolution issue. The screen is vertical 800x480 px, but seems to appear almost a square (800x768), with a black band on right. Tried with RealVNC and UltraVNC as viewers. When the screen is horizontally rotated, the black band on the right is smaller (resolution 832x480). Looking on ADB is correctly reporting the original screen resolution: Display DisplayDeviceInfo{"droidVNC-NG": uniqueId="virtual:net.christianbeier.droidvnc_ng,10230,droidVNC-NG,0", 480 x 800, modeId 4, defaultModeId 4, supportedModes [{id=4, width=480, height=800, fps=60.0, alternativeRefreshRates=[]}], colorMode 0, supportedColorModes [0], hdrCapabilities null, allmSupported false, gameContentTypeSupported false, density 240, 240.0 x 240.0 dpi, appVsyncOff 0, presDeadline 16666666, touch NONE, rotation 0, type VIRTUAL, deviceProductInfo null, state ON, committedState UNKNOWN, owner net.christianbeier.droidvnc_ng (uid 10230), frameRateOverride , brightnessMinimum 0.0, brightnessMaximum 0.0, brightnessDefault 0.0, FLAG_PRIVATE, FLAG_PRESENTATION, installOrientation 0}

[bk138]

@RaulMerelli i think you're experiencing #145 actually?

[RaulMerelli]

@bk138 Sorry, I didn't see that there was this specific issue. Seems exactly the same problem.

[bk138]

@bk138 Sorry, I didn't see that there was this specific issue. Seems exactly the same problem.

But you're seeing an extreme form...

[RaulMerelli]

@bk138 Sorry, I didn't see that there was this specific issue. Seems exactly the same problem.

But you're seeing an extreme form...

Quite a big margin in fact:

480x800 could be a particular screen resolution.

[bk138]

@5A52 I have a customer with a similar problem. Which Android version are you using?

[5A52]

@5A52 I have a customer with a similar problem. Which Android version are you using?

Android 12,13,14. But all of them samsung oneui (4.1,5.1,6.1,6.1.1).
Issue does not hurt me, as input does not work anyway on second display. But if you need I can collect logs, or any other information.

[bk138]

@5A52 As the the issue does not hurt you and the situation w/ my customer turned out to be an OEM bug, I'll document secondary display support and close this.