alt Hacker NewsThis is a decades-old design pattern when CPU >> IO. Emacs has been doing just that since the 80s, when people were complaining about "Eight Megs And Constantly Swapping". See "redisplay" [1]
This minimizes screen flash. You can't rely on terminals doing double-buffering.
[1] https://github.com/emacs-mirror/emacs/blob/c29071587c64efb30... or a more user-friendly overview, Daniel Colascione's seminal "Buttery Smooth Emacs", snapshotted at e.g. https://gist.github.com/ghosty141/c93f21d6cd476417d4a9814eb7...
Replies
strix_varius • today at 12:42 AM
lol what? There are definitely ways to make non flashing terminal UIs without this total insanity.
➕ show 1 reply
xiaoyu2006 • today at 2:27 AM
Even with that, 1G of RAM usage is still not justified.
> This minimizes screen flash. You can't rely on terminals doing double-buffering.
GUI and TUI have different architecture model. Most GUI have have a 2D surface that is redrawn multiple times per second. Double buffering is for decoupling update and render. TUI is a grid of characters that are updated one at a time via an active element, the cursor. Double buffering there is very wrong. Like adding airbags to a bicycle.
There’s a reason you see most old TUI either have an option to redraw the screen (automatically like top, or manually) and those that have a scrolling option allow to scroll by page. The TTY (the underlying concepts) used to be slow and it can be slow today as well (ssh connection). You need to be thoughtful about whole screen updates.