support setting non-supported modes (resolution)

[Jonas G. Drange]

Reproduce:
run mirout

What happens:
I only see one resolution supported.

What should happen:
I should see more resolutions, like I do on unity7.

I guess, if in doubt, “support” the same ones as xrandr.

[Bill Filler (bfiller)]

this is needed for system-settings, user expects to be able to change resolutions as they did in unity7

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Chris Halse Rogers (raof)]

OK, there's a design discussion to be had here.

In these cases, mirout is correct - your display has exactly one mode it can be driven at. X adds a whole bunch of fake “standard” modes, but they're just that - fake. Selecting one of the fake modes does not change the video mode; instead, it scales the rendering up to the monitor's mode.

What is the user requirement here?

I'd prefer the Mir API to accurately reflect the capabilities of the system, but one of those capabilities is that we can scale content. If the user-requirement is “I'd like everything on my screen to look bigger”, we can do that.

Indeed, this seems to be the Apple approach - https://support.apple.com/en-au/HT202471 - there's the “optimal resolution” button, and then the “make everything larger or smaller” option.

[Chris Halse Rogers (raof)]

(Note that the user requirement *cannot* be “I'd like to change the display mode”, because Unity 7 doesn't change the display mode in these cases ☺)

[Daniel van Vugt (vanvugt)]

The discussion is already ongoing in bug 1196239, but that one needs a more current description. Please update bug 1196239 as appropriate.