在 2020年1月2日 +0800 AM12:23，Eli Zaretskii <eliz@gnu.org>，写道：

Date: Wed, 1 Jan 2020 11:47:49 +0800
From: HaiJun Zhang <netjune@outlook.com>
Cc: "38807@debbugs.gnu.org" <38807@debbugs.gnu.org>

My understanding of the display flow:
1. an event comes which causes redisplay

More often than not, it is not an event, but a command that changes
Lisp data (buffer text, overlays, text properties, position of point,
new or deleted windows, etc.).

Thanks for your explanation.

2. the display engine prepares the glyph matrix
3. convert the glyph matrix to bitmap and display it

I think lots of work are in 2.

Actually, 3 is also a lot of work.

Then 3 can be done in a separate thread from 2 and 1?