Like the X11 and Wayland backends, re-work how the cursors are being
handled. So, we use a hash table to cache up the HCURSORS that we
create along the way.
We still need to cache up the icon/cursor themes since this is something
that is not part of Windows but was added on to support icon/cursor themes
such as Adwaita on Windows, but should be in-line with what is going on in
GdkCursor.
Also, remove the _gdk_grab_cursor global variable in gdkprivate-win32.h,
and replace it with another variable in the GdkWin32Display structure,
to make things cleaner in the process.
https://bugzilla.gnome.org/show_bug.cgi?id=773299
Load themed cursors from the same places they are loaded on freedesktop systems,
but use W32 API functions to do so (works for .cur/.ani cursors instead of X
cursors).
Refactor the code for cursor handling. Prefer loading cursors by name.
Do not load actual cursors when loading the theme. Find the files and remember
the arguments/calls for loading them instead. Keeping HCURSOR instance in the
hashmap would result in multiple GdkCursors using the same HCURSOR. Given that
we use DestroyCursor() to off them, this would cause problems (at the very
least - DestroyCursor() would fail).
Store GdkCursor instances in a cache. Update cached cursors when theme changes.
Recognize "system" theme as a special (and default) case. When it is set,
prefer system cursors and fall back to Adwaita cursors and (as a last resort)
built-in X cursors. Otherwise prefer theme cursors and fall back to system and
X cursors.
Force GTK to use "left_ptr" cursor when no cursor is set. Using NULL makes
it use the system default "arrow", which is not the intended behaviour when
a non-system theme is selected.
Ignore cursor size setting and query the OS for the required cursor size, as
Windows (almost) does not allow setting cursors of arbitrary size.
https://bugzilla.gnome.org/show_bug.cgi?id=749287
There are sure regressions but basic stuff seems to be working
again after all the API breakage done with comments like
"Win32 and Quartz need to be ported still."
