Option: Manually set windowed resolution
The game's windowed-mode loads its display resolution from an ini file located here
~/.local/share/FasterThanLight/settings.ini
This file has a small section for manual display size, here is the original and my settings for a thin window manager on a 1920x1080 dispaly.
Original Text:
#Manual resolution choices - overrides anything in the options
#Set manual to 1 and then change the resolution
#Does not check if values are valid. Use with caution.
#If you do not support GL_ARB_framebuffer_object, "stretched" will not function
manual=0
screen_x=0
screen_y=0
windowed=0
stretched=0
My Config (Cinnamon WM + Numix Window Borders 1080x1920 Display):
#Manual resolution choices - overrides anything in the options
manual=1
screen_x=1918
screen_y=1024
windowed=1
stretched=1
The summary of the problem as I understand it, FTL uses SDL (Simple DirectMedia Layer), for both receiving keyboard events, and drawing a desktop window. From what I understand, its a limitation (really out of scope) for SDL to integrate with a window manager (I suppose you could even write a window manager with SDL!). A bit unrelated, but one topic asking how to handle ALT+Tab in SDL suggests forfeiting SDL Altogether and using the GTK desktop-programming toolkit instead, which is a lot of hard work [and not necessarily a very practical work] to get alt tab support and other minor desktop integrations.
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