Fullscreen mode always uses primary monitor

[Benedikt Straub]

On a multiple monitor setup, Widelands always uses the primary monitor in fullscreen mode. It should be possible to select which monitor to play on in the options, ideally with an option to use all of them.

[GunChleoc (gunchleoc)]

I don't have a multi-monitor setup, but since we don't have any code to handle this, I'm setting the bug to confirmed.

[kaputtnik (franku)]

I have a multimonitor setup and my display manager/window manager have always trouble with it :-D

The problem here is that it is a problem of window/display manager configuration in conjunction with the graphics adapter/driver, not a problem of a single program.

> ideally with an option to use all of them.

This depends also to the window manager and graphics driver, not to a program. Example: https://www.facebook.com/photo.php?fbid=1386381771377233&set=o.326816027402782&type=3&theater

What i want to say: There are so many possibilities, also depending on the operating system and the graphics driver, that it will be impossible to achieve a solution for widelands to this bug.

I would vote to mark this bug as invalid or won't fix.

[Benedikt Straub (nordfriese)]

I don´t think it only depends on the graphic driver and window manager. The default behavior on my system is that a fullscreen window is placed on the monitor it was located on before maximizing. Widelands already has a different behavior, so I´d take a wild guess that the SDL can have some influence here.
Other programs have other handling methods. For example, OpenTTD allows me to choose a resolution equal to the combined size of both monitors, and when entering fullscreen mode at that res, the game uses both monitors. That´s what I would love to have for Widelands.
I don´t know the SDL very well, but it might be worth to check whether it allows to implement such a behavior.

[GunChleoc (gunchleoc)]

SDL does have some functions for listing the monitors, so we should be able to take it from there and at least improve the situation - staying on the same monitor while switching the mode would be good.

Code snippet for iterating through the available monitors:

https://wiki.libsdl.org/SDL_GetCurrentDisplayMode

[GunChleoc (gunchleoc)]

Migrated to https://github.com/widelands/widelands/issues/1079