Re: Development of custom virtual monitor

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 25 Sep 2023, Arun Mani J <J.ArunMani@proton.me> wrote:
> Hey all
> I would like to develop a virtual monitor, regarding which I need help. The situation is, I need to design a virtual monitor and make it a top-level window. I should be able to move windows to this monitor, render them and do other things which can be done in a physical monitor.
>
> Of course, X11 and Mutter provide APIs to create virtual monitors. but I want it to be as DE independent as possible. So I'm looking for a low-level solution which might interface with the Kernel to act as a universal virtual monitor.
>
> The closest I can get to is DRI and KMS. But I'm stuck on how to take it forward as in how to fake this entire scenario.
>
> My assumption of the situation is like, I create a file in /dev that signals "plugging-in" of a monitor, which makes Kernel load my custom driver. Window managers, DRIs write to this file, as in write the data to be shown on the monitor and my driver would take care of rendering those data on a top-level window. But I think, this won't be that easy...
>
> This is similar to a virtual machine, but I just want to emulate a monitor than a processor or so.
>
> Any pointers and documentation regarding this is highly appreciated. Yes, I'm new to such kinda stuff but I'm ready to invest time and learn :)

Maybe look into drm/vkms [1][2].


BR,
Jani.


[1] https://docs.kernel.org/gpu/vkms.html
[2] https://docs.kernel.org/gpu/drm-uapi.html#using-vkms-to-test-drm-api


-- 
Jani Nikula, Intel