Libnotify brightness appears on different screen to brightness change taking place

[Paul Sladen]

Filing here, as the multi-monitor story is still under design, and also because any solution will likely require adjustments across many components (libnotify, libindicator, gnome-settings-daemon, panel).

With a multi-monitor setup (large screen above a netbook screen) I used the hardware combination keys (Fn+F2/Fn+F3) to adjust the brightness. The notification of this change appeared on the other screen.

Possibly it would be better that indicators applying to a specific display show only on that specific screen. The only two that really come to mind are hardware brightness changes and rotation feedback, although the latter is probably not required as the change should ideally be obvious+reversible to the user at the point that they've made it.

To reproduce:
  1. Set up a laptop. Observe that this has a display, and ensure that it is working
  2. Set up an external monitor. Observe that this has an image, and ensure that it is working.
  3. Open a full-screen window on the external monitor, focus and leave mouse over it.
  4. Press the buttons just below the external monitor. Observe the amount of transmitted light on the external display being increased and decreased. Note that the (hardware) percentage appears on the external display only. This is logical.
  5. Press the buttons just below the internal monitor. Observe the amount of transmitted light on the internal display being increased and decreased. Note that the (software) percentage appears on the *external* display. *This is illogical*.
  6. Move the full-screen window to the internal monitor, focus and leave mouse over it
  7. Press the buttons just below the external monitor. Observe the amount of transmitted light on the external display being increased and decreased. Note that the (hardware) percentage appears on the external display only. This is logical.
  8. Press the buttons just below the internal monitor. Observe the amount of transmitted light on the internal display being increased and decreased. Note that the (software) percentage appears on the internal display only. This is logical.

Case 5 is illogical, and feedback is occuring in a different and disconnected place to where it being (a) initiated and (b) impacting.

This is different to normal use of a keyboard where the feedback is provided at the point of working (eg. entering text in a window on the external screen) or in a global/intangible way (volume control).

A similar situation might occur with a tablet display (such as ThinkPad X61 Tablet) which has hardware rotation buttons. The point of input and point of output would both be the internal adjacent display.

[Paul Sladen (sladen)]

Had a reply back from Stewart Wilson that the Multi-Monitor prototype/research/specification will have a section on the placement of OSD notifications and this will probably be integrated/linked from there.

[Matthew Paul Thomas (mpt)]

<https://wiki.ubuntu.com/NotifyOSD#position> already specifies which display notification bubbles should appear on.

[Bryce Harrington (bryce)]

Reproduced case 5 on precise with Intel gfx hardware and external monitor.

[Bryce Harrington (bryce)]

Testing on unity 5.2 shows this has been fixed.