Make the class in the XrmGetResource call be the same as the resource
name we are trying to retrieve, "Xft.dpi". Nowhere in the documentation
it is mentioned that the class name can be NULL so it is better to be
cautious and set it to a value that is unlikely to affect anything.
Calculating the screen dpi on a per-monitor basis can cause
inconsistencies if multiple monitors with slightly different dpis are
used and in some cases it might not be the expected behaviour.
As such, the per-monitor dpi calculation was changed from a default
fallback to an opt in experimental feature and the default value of 96
will be used for the dpi if Xft.dpi is not set.
In the future, depending on how we decide to continue, we can either
move this setting in the global configuration section and fall back to
the X11 display dpi as the default or simply always use the per-monitor
dpi calculation. But to preserve backwards compatibility, this decision
can wait until the next major release.
Previously, we were getting screen info every time we tried to move the
window. To improve the situation, information about the available
screens is initialised once when dunst starts and further behaviour
depends on the compile-time options used.
If Xrandr is enabled, screen information is updated when an
XRRScreenChangeNotify event is received, meaning only when the screen
layout changes.
If Xinerama is enabled, screen information is only updated on startup.
This behaviour might be changed later.
If none are enabled, then dunst assumes only one screen and ignores all
multi-monitor options.
Since we are adding Xrandr support to allow for automatic dpi detection,
split screen handling code into a new file as part of the effort to
simplify x.c
x.c has grown into an unmaintainable blob. Moving it in its own
subdirectory is the first step to splitting it into submodules each of
which will have a well defined job so that a lot of the code can be
abstracted to improve readability and make it much easier to maintain.
This process will be done one small part at a time only when we need to
change significantly change a part of the file, there is no need to
break what already works.
