Commit Graph

9 Commits

Author SHA1 Message Date
bakkeby 5c7d8ab1ad auto-sync: draw on idle to avoid flicker/tearing
st could easily tear/flicker with animation or other unattended
output. This commit eliminates most of the tear/flicker.

Before this commit, the display timing had two "modes":

- Interactively, st was waiting fixed `1000/xfps` ms after forwarding
  the kb/mouse event to the application and before drawing.

- Unattended, and specifically with animations, the draw frequency was
  throttled to `actionfps`. Animation at a higher rate would throttle
  and likely tear, and at lower rates it was tearing big frames
  (specifically, when one `read` didn't get a full "frame").

The interactive behavior was decent, but it was impossible to get good
unattended-draw behavior even with carefully chosen configuration.

This commit changes the behavior such that it draws on idle instead of
using fixed latency/frequency. This means that it tries to draw only
when it's very likely that the application has completed its output
(or after some duration without idle), so it mostly succeeds to avoid
tear, flicker, and partial drawing.

The config values minlatency/maxlatency replace xfps/actionfps and
define the range which the algorithm is allowed to wait from the
initial draw-trigger until the actual draw. The range enables the
flexibility to choose when to draw - when least likely to flicker.

It also unifies the interactive and unattended behavior and config
values, which makes the code simpler as well - without sacrificing
latency during interactive use, because typically interactively idle
arrives very quickly, so the wait is typically minlatency.

While it only slighly improves interactive behavior, for animations
and other unattended-drawing it improves greatly, as it effectively
adapts to any [animation] output rate without tearing, throttling,
redundant drawing, or unnecessary delays (sounds impossible, but it
works).
2020-05-20 14:15:57 +02:00
bakkeby d26b46ffa7 Adding invert patch 2020-03-29 15:38:16 +02:00
bakkeby e7cfd5ae16 better Input Method Editor (IME) support (35f7db) 2020-03-24 11:25:39 +01:00
bakkeby 9f1a2db7c5 Adding font2 patch as per request #3 2020-03-21 16:41:43 +01:00
bakkeby 352170eec8 Adding st embedder patch 2020-01-07 14:05:53 +01:00
bakkeby dc915b6056 Adding note about flexipatch-finalizer 2019-10-16 12:05:53 +02:00
bakkeby cfecd195ba Adding relativeborder, fix-keyboard-input, iso14755, visualbell, rightclicktoplumb, boxdraw and keyboard-select patches 2019-09-17 15:16:22 +02:00
bakkeby 4bd0ed3327 Adding xresources patch 2019-09-16 14:21:09 +02:00
bakkeby 7615c2f0aa Adding fixime, newterm and opencopied patches 2019-09-16 12:40:07 +02:00