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[STR Pending]

Link: https://www.fltk.org/str.php?L3521
Version: 1.4-feature


Well, this seems to be more complicated than anticipated. Basically I think
that my simple approach doesn't work - we need a platform specific patch
instead.

As I understand it now macOS does the horizontal/vertical swap for us even
before the event reaches FLTK. Hence I conclude that we need to do the same
(swap horizontal/vertical) for scrollwheel events on Windows and Linux in
FLTK. Note that (according to the FLTK code I investigated) both Windows
and Linux have builtin "horiontal mousewheel" support, but this doesn't
help users with a simple mouse with only one wheel. Only for the latter
we'll do "horizontal mousewheel emulation with Shift key".

I don't think we can resolve the issue for the XQuartz and/or VirtualBox
under macOS case though. If we handle these cases in our X11 event handling
*and* macOS does its own swapping *before* XQuartz or VirtualBox "see" the
event then we'll always get a double swap, i.e. we can't handle the
"horizontal mousewheel emulation" - unless we also have a user/system
option to disable "horizontal mousewheel emulation" at runtime for users on
these platforms.

I'll work on a better (platform specific) patch later.


Link: https://www.fltk.org/str.php?L3521
Version: 1.4-feature