Hello Keith,
I have verified that the current implementation actually works exactly
as suggested. Initially, an auto-generated monitor exists. Adding a user
defined monitor replaces it. Removing the user defined monitor restores
the auto-generated monitor.
I have refined the randr spec regarding this. I also changed the
definition to allow more than one monitor per output. The change can be
found at
https://gitlab.freedesktop.org/xorg/proto/xorgproto/-/merge_requests/64
After I got some advice from Oliver how to improve my PR, I updated the
description there and added my findings as well as an estimation what
side effects this change could have. This PR to xorg-server is at
https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/981
Please let me know if there is anything missing or if some more
discussion is required to get this merged.
Kind regards,
Michael.
Michael Wyraz <mich...@wyraz.de> writes:
For the second monitor, the output must be set to "none" which is
obviously wrong since it is connected to a device. The reason why it is
set to "none" is some code in xserver that removes an monitor if another
one is added to the same output:
That's actually required in the RandR spec:
For each output in 'info.outputs, each one is removed from all
pre-existing Monitors. If removing the output causes the list of
outputs for that Monitor to become empty, then that Monitor will
be deleted as if RRDeleteMonitor were called.
The notion of splitting one physical output into multiple virtual
monitors was not considered when this extension was defined, which is
why it doesn't work. I don't see any particular reason for *not*
supporting your use case.
However, there are subtleties here. We want to remove any automatically
created 'Monitor' objects when mapping user-specified monitors to
them, and we want to re-generate automatically generated 'Monitors' when
all virtual monitors associated with an output are removed.
I think what we want is:
* If no user-specified Monitors map to a particular Output, then automatically
create a Monitor for that Output
* If any user-specified Monitors map to a particular Output, then
remove the automatically generated Monitor for that Output.
In the current spec, there's no real separation between user-specified
and automatically-generated Monitors, I think that would be necessary to
make this work?
