Re: master 5eb729c0b36 1/2: Report touch events on MS-Windows

[Po Lu <luangruo@yahoo.com>]

Po Lu via Mailing list for Emacs changes <emacs-diffs@gnu.org> writes:

> branch: master
> commit 5eb729c0b36a31869cf4928bc7bf5111b6f59ebb
> Author: Po Lu <luangruo@yahoo.com>
> Commit: Po Lu <luangruo@yahoo.com>
>
>     Report touch events on MS-Windows
>     
>     * etc/NEWS: Announce change.
>     
>     * src/w32fns.c (RegisterTouchWindow_fn): New function.
>     (w32_createwindow): Assign a base value for touch event
>     identifiers to the frame, and register for touch input.
>     (w32_wnd_proc): Forward WM_TOUCH/WM_TOUCHMOVE messages to the
>     main thread.
>     (globals_of_w32fns): Load RegisterTouchWindow from user32.dll.
>     
>     * src/w32term.c (w32_read_socket) <WM_TOUCH>: Detect WM_TOUCH
>     events, compare and record their touch points with and into the
>     frame's record of their prior state, and report the same to Lisp.
>     (pfnCloseTouchInputHandle, pfnGetTouchInputInfo): New variables.
>     (w32_initialize): Load the above functions from user32.dll.
>     
>     * src/w32term.h (MAX_TOUCH_POINTS): New definition.
>     (struct w32_output) <touch_ids, touch_x, touch_y, touch_base>:
>     New fields.

Folks, I got around to writing this code earlier than anticipated, but
it has not been tested with real user input.  If there are MS-Windows
users with the relevant touch input hardware reading this, let one of
them come forth and do us this trivial service, and his efforts will be
appreciated.