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The current implementation of the display dialog does mostly support cloning your display to a second monitor. Xrandr and xfconf can do a lot more than that (e.g. extend and adjust resolutions) and this should be made more accessible to users. In fact this is one of the more frequently asked questions, or requested features. (There was even an episode in the 2011 FOSDEM where an Xfce-dev couldn't get the beamer to work from his notebook for his presentation.)
Currently there's only a list of displays and a few combobuttons to change settings. The list is a bit too much in my opinion, because most people won't have many more than 2 displays maximum.
Features / ToDo
This is the list of features we want to implement in the first stage:
- Support extended desktop mode for 2 monitors
- Reflect this in the settings dialogs
Other features / problems:
- Support setting the primary monitor (Related bug: 9338)
- Improve visual representation of monitor-positions (e.g. via using iconview over treeview)
- Save settings based on EDID (automatic “display-setup-profiles”), i.e. different EDIDs at work and at home would result in always having the right config automatically, even if the screens have the same resolution (this would be particularly interesting with having primary monitor support in the panel)
The minimal dialog should only be called automatically when a new display is plugged in. It should provide users quick access to the most-used modes:
- Extend desktop to the left
- Extend desktop to the right
- Mirror displays
Furthermore it should contain a button linking to the display-settings dialog (see next section), in case the user wants to configure the new display more in depth (e.g. laptop docking). An additional checkbox should enable/disable presentation mode (see section above).
Theoretically (and according to Ubuntu's Multi-Monitor Spec) it's possible to (heuristically) detect whether the connected device is a TV or a Projector or an external monitor. We could try to use this information to set the window-title (at least).
This design currently features three 128px icons for the three basic modes, a tickbox for presentation-mode and a button to launch the display settings dialog.
Display Settings Dialog
This dialog will enable the user to change all the settings of all connected displays. The set of options basically depends on what RandR and the display drivers offer.
Improve the current dialog
To improve Xfce's dialog one would have to implement the “extended desktop”-mode of RandR, i.e. positioning the monitors “left-of” and “right-of”. (Theoretically there's also “above” and “below”, but in most scenarios multiple monitors are aligned horizontally.) The “mirror displays”-checkbox would make the combobox for choosing the position of the screen insensitive.
Status / Implementation
- Add the 10sec-reset-timeout dialog just to be sure
- Debug/fix segfault after setting Mirror, then Extend Right
4 options: Only Primary, Mirror, Extend Right, Only Secondary draw icons implement in code
Hook up Advanced button Consider dropping “presentation mode”
- Fix xfconf channel binding warning
Add code for “identifying popups”
- Use xfce4-notifyd's gtk-style
- Fix wrong position and values after a display has been disabled
Re-color the currently selected display
- Check why xrandr works better with Nvidia proprietary than our code
- Applying new positions works every second time. Debugging output about desktop dimensions only gets printed every second time (TRACE[displays.c:800] xfce_displays_helper_channel_apply(): Desktop dimensions: 3200×1200 (px), 722×271 (mm).) I would assume that the problem lies there: the desktop dimensions don't get changed in time for the first try, so the driver falls back to mirror-mode. The second time the desktop dimensions are already changed from the last try and then applying new positions works. What supports this hypothesis is that switching from right-of to left-of seems to work fine. But e.g. from right-of to below it takes 2 tries again and vice versa (because the desktop dimensions would again have to be changed). — simon 2012/10/11 10:55
- Code review
Fix rotation code with extended desktop mode Change rotation-combo-entry-name from “normal” to “none”
- Fix 3 commit authors (merge locally, then rebase interactive on origin/master and set a new committer)
- Celebrate the release!
- The vertical/horizontal alignment of monitors (especially those with different resolutions) cannot be set in the current proposals. E.g. an external monitor with 1280×1024 and a laptop monitor with 1280×768, the ext-mon could be right of the laptop but then either at X=0 or at X=1024-768 depending on how you're using your desktop (panels etc.)
- Not all drivers send proper notifications so that we can trigger the –minimal dialog.