[Bug 30184] New: Take advantage of xrandr 1.3 features

http://bugs.winehq.org/show_bug.cgi?id=30184

Bug #: 30184
           Summary: Take advantage of xrandr 1.3 features
           Product: Wine
           Version: 1.4-rc6
          Platform: x86
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: winex11.drv
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

See bug 30154

"""
(In reply to comment #18)
> Wine is a user level application, it's by definition a kernel/vidoe driver
> bug if doing a simple video modes query (just once at start up!) makes X
> block for several seconds.

I don't think anyone denied there was a driver/hardware bug involved as well.
But that doesn't change the fact that the way XRandR is currently used in Wine
causes completely unnecessary EDID polls.

This doesn't happen just once on startup either. As the linked source shows,
calling XRRGetScreenInfo() causes a poll. X11DRV_XRandR_GetCurrentMode() calls
XRRGetScreenInfo(). This is what is used to implement the ENUM_CURRENT_SETTINGS
part of the EnumDisplaySettings*() calls, and it's certainly not unheard of for
applications to call those.

You can certainly argue that this bug isn't a very high priority for Wine, and
that it's more important to get the driver fixed so that polls aren't so
expensive. You can't argue that Wine doesn't cause these polls.
> Wine doesn't do anything of the listed below things as the reporter claims:
> > - wine is requesting the information again and again

Calls to EnumDisplaySettings*() with ENUM_CURRENT_SETTINGS do this.
> > - and is forcing xrandr to do a reprobe instead of just getting the current
> >
> > information.

Just about any XRandR 1.2 query will do this. The way to fix it is to use
XRandR 1.3 RRGetScreenResourcesCurrent for querying, and e.g.
RRScreenChangeNotify events to get notified of configuration changes. This is
practically needed for proper multi-head support anyway, and listening for the
appropriate events will also fix the issue where applications are unaware of
mode changes by other applications.
"""