add new resolutions to Xdummy on the fly - dummy driver needs randr support added?

[Antoine Martin]

Instead of finding the nearest match, we should just add the modeline, assign it to the output then select it.
This would allow us to match the client's screen size exactly.

(somewhat blocked by #10)

[Antoine Martin]

this patch would add a new mode to Xdummy so we can use it... but does not work

[Antoine Martin]

After ​asking xorg-devel, it would seem that the dummy driver does not support randr - or at least not fully.

The patch above attempts to replicate xrandr's command line functionality and even includes its own modeline calculator, so from xpra's side it is pretty much ready.

[Antoine Martin]

Not heard back, and less critical now that the default config contains many of the typical resolutions found on desktops and even android devices.

[onlyjob]

refreshed patch to apply over 0.6.1

[Antoine Martin]

Closed #186 (duplicate - some info there)

[Antoine Martin]

Asked xorg dev again: ​RFC: dummy driver RandR improvements?

Some other links:

• ​Fake Xinerama for X devs
• ​Fake xinerama on github
• ​PATCH: make Xephyr resizeable

[Antoine Martin]

Forgot to update this ticket:

• we now have wiki/FakeXinerama support
• better DPI support (see #163)

[Antoine Martin]

Nicolas Boichat has just posted X11 patches to do exactly this!: ​PATCH dummy: Add support for custom resolutions (RandR 1.2)

Maybe this will fix #728
We'll just have to ensure this works with DPI (#163) - that we deal with #732 if possible, see also #349

[Antoine Martin]

Looks like the discussion of what to do for randr 1.2 support is ongoing: ​Cleanups and RandR 1.2 support, with different implementations suggested.

And so this will have to wait until this gets merged in one form or another, and maybe we only have to package it then which would be great (assuming that the new code can be built against older servers that is...)

[Antoine Martin]

Maybe this can help us: ​RandR 1.5 Brings Monitor Objects & Tile Support For X.Org

[Antoine Martin]

Re-post: ​xvfb: add randr support (v2)

I think we should update the dummy driver with the same changes.

[Antoine Martin]

In one of the responses to the patch above: ​http://lists.x.org/archives/xorg-devel/2015-June/046666.html links to: ​PATCH xf86-video-dummy 0/6: Cleanups and RandR 1.2 support - which is a better approach IMO.

[Antoine Martin]

See also #969, in particular the ramdac fix in ticket:969#comment:3

[Antoine Martin]

dummy randr 1.2: patch 1 Remove pointless empty functions

[Antoine Martin]

dummy randr 1.2: patch 2 Delete XV stuff

[Antoine Martin]

dummy randr 1.2: patch 3 Delete dPtr->screenSaver

[Antoine Martin]

dummy randr 1.2: patch 4 Remove DGA support

[Antoine Martin]

dummy randr 1.2: patch 5 Get rid of dPtr->FBBase

[Antoine Martin]

dummy randr 1.2: patch 6 Support RandR 1.2

[Antoine Martin]

just tried the patch series above and hit a snag: ​my xorg-devel reply

[Antoine Martin]

See also: ​MST monitors and the proposal for RandR 1.5 which would have the concept of "monitors" (without requiring us to have virtual CRTCs attached to them apparently)

[Antoine Martin]

No movement on this upstream, re-scheduling.

[Antoine Martin]

The randr v2 patch has been merged: ​http://lists.x.org/archives/xorg-devel/2015-December/048228.html.
Commit: ​3d68d1f26709ecb5ce22a9baa0d3d8162574ed6a.
So either we figure out how to use the same code in Xdummy, or we switch back to Xvfb with newer versions?
Will have to test this new stuff: re-scheduling.

[Antoine Martin]

re-scheduling

[Antoine Martin]

We're not alone in needing this: ​xf86-video-dummy: resize to exact resolution from Chrome Remote Desktop developer Erik Jensen.

[Antoine Martin]

Milestone renamed

[Antoine Martin]

I don't have time for this, new links:

• ​re: xf86-video-dummy: resize to exact resolution: Xvfb is as maintained as any other server we build
• ​re: xf86-video-dummy: resize to exact resolution: Which approach seems more likely to gain traction? Without a champion for either one, neither. :)

[Antoine Martin]

for testing the latest upstream patches for dummy

[Antoine Martin]

Recent discussion: ​remove dead code in dummy driver: In 2014 I had also modified the dummy driver while working with Teradici Corporation to support not only arbitrary pixel dimensions, but also multiple monitors. The latter feature might not make sense to some folks, but if you have a server-side Xserver mapped to a hardware thin client sitting across a network, which has multiple physical monitors attached, you want the Xserver to be configured in the exact same manner as the tin client. Even though there is just a virtual framebuffer in main memory, X applications need to know the number/size/location of monitors so that toolbars are placed properly, windows are fullscreen'ed properly, etc. And when the user moves from one hardware thin client to another, which may have a different monitor configuration, the Xserver session needs to change to that configuration.

[Antoine Martin]

This will also make #1008 redundant.

[Antoine Martin]

Raising again.

This is the commit that added randr to Xvfb: ​vfb: add randr support (v2)