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[STR Pending]

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


FWIW, here's my take on this issue. According to MS docs the MK_SHIFT bit
is set if Shift is pressed during the event. I'm using this to invert the
wParam value of the WM_MOUSEHWHEEL event which is also executed in the
FALLTHROUGH case (WM_MOUSEWHEEL with Shift):

        // FALLTHROUGH
      case WM_MOUSEHWHEEL: {
	static int delta = 0; // running total of all motion
	// ** new code starts below
	int wparam = (SHORT)(HIWORD(wParam));
	if (LOWORD(wParam) & MK_SHIFT)
	  wparam = -wparam;
	delta += wparam;
	// ** new code ends above
	Fl::e_dy = 0;
	Fl::e_dx = delta / WHEEL_DELTA;
	delta -= Fl::e_dx * WHEEL_DELTA;
	if (Fl::e_dx)
	  Fl::handle(FL_MOUSEWHEEL, window);
	return 0;
      }

This patch, however, has the side effect that it would also invert the
scroll /direction/ of real horizontal mousewhee levents (WM_MOUSEHWHEEL).

It works, but I'm not entirely satisfied with this approach. Maybe we need
a longer but more explicit patch. Ideas?


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