Re: MS Windows double buffering

[Po Lu <luangruo@yahoo.com>]

Po Lu <luangruo@yahoo.com> writes:

> From ee8cc91559c04a4f21a1ad14ff5461453638145e Mon Sep 17 00:00:00 2001
> From: Po Lu <luangruo@yahoo.com>
> Date: Fri, 29 Apr 2022 11:33:41 +0800
> Subject: [PATCH] Implement double buffering on MS Windows
>
> * etc/NEWS: Announce changes.
> * src/w32fns.c (w32_set_inhibit_double_buffering): New function.
> (w32_wnd_proc):
> (Fx_create_frame):
> (w32_create_tip_frame): Set `inhibit-double-buffering' parameter.
> (w32_frame_parm_handlers): Add new handler.
>
> * src/w32term.c (w32_show_back_buffer):
> (w32_release_paint_buffer): New functions.
> (w32_frame_up_to_date): Show back buffer if applicable.
> (w32_buffer_flipping_unblocked_hook): New hook.
> (w32_scroll_run): Use BitBlt to scroll instead of window
> scrolling functions.
> (w32_scroll_bar_clear): Don't clear scroll bars when double
> buffered.
> (w32_read_socket): Flip buffers after reading input events in
> some cases.
> (w32_free_frame_resources): Free back buffer.
> (w32_create_terminal): Add new hook.
>
> * src/w32term.h (struct w32_output): New fields for handling
> back buffers.
> * src/w32xfns.c (select_palette): Fix indentation.
> (get_frame_dc, release_frame_dc): Return back buffer when
> appropriate and set dirty flag.

I fixed a few minor problems with this, synchronized parts of the tool
bar code with X to fix a bug, and installed the resulting changes, since
they seems to be working fine for me and eliminates all of the dreadful
flickering that was previously present on MS Windows.