FLTK's fullscreen_x() function will always put the window on a high
level (NSStatusWindowLevel = 25), even if the window doesn't have focus.
This causes the OptionsDialog to end up behind the DesktopWindow when
the fullscreen function is called. Until we can rest assured that most
people building TigerVNC will use a fixed version of FLTK, we will need
this workaround.
It was only possible to capture either the current, or all displays
previously. This could become an issue if you want to show a vnc session
over only a selected set of displays, because then we only want to
capture those displays.
The solution in the commit was chosen because it handles all cases - by
looking at what monitors are enclosed by the viewport the implementation
is independent on any configuration, but instead captures the monitors
actually being used.
We won't always be on the primary monitor, so check which color space
we're actually using right now. For offscreen stuff we assume a standard
sRGB color space.
Samuel Mannehed
Hugo Lundin
Pierre Ossman
DRC
Adam Tkac
Constantin Kaplinsky