Before, we applied delayed rendering (that is, we gave the client a
chance to do more writes before we scheduled a render refresh) only
when the renderer were idle.
However, with e.g. a high keyboard repeat rate, it is very much
possible to start the render loop and then never break out of it while
receiving keyboard input.
This causes screen flickering, as we're no longer even trying to
detect the clients transaction boundaries.
So, let's rewrite how this is done.
First, we give the user the ability to disable delayed rendering
altogether, by setting either the lower or upper timeout to 0.
Second, when delayed rendering is enabled, we ignore the frame
callback. That is, when receiving input, we *always* reschedule the
lower timeout timer, regardless of whether the render is idle or not.
The render's frame callback handler will *not* render the grid if the
delayed render timers are armed.
This means for longer client data bursts, we may now skip frames. That
is, we're trading screen flicker for the occasional frame hickup.
For short client data bursts we should behave roughly as before.
This greatly improves the behavior of fullscreen, or near fullscreen,
updates of large grids (example, scrolling in emacs in fullscreen,
with a vertical buffer split).
There's a race/chance that we'll have disarmed the delayed rendering
timers and still get the call.
While it _shouldn't_ be anything to read from the timers, it doesn't
hurt to try. And, if the timers *are* readable, not reading them means
we'll end up in an infinite FDM loop.
When resizing in alt mode, we never updated the saved 'normal'
cursor. This meant that when we exited alt mode, the cursor would be
positioned where it was in the old pre-resize/reflow grid.
Now, we update the saved cursor in the same way we update visible
cursor. The result is that when we exit the alt screen, the cursor
is restored to the same coordinates it would have been updated to had
the resize been done in the 'normal' screen.
They aren't really user configurable. At least not yet.
However, with this, we now handle raw key codes just like the normal
key bindings. Meaning, e.g. ctrl+g, ctrl+a, ctrl+e etc now works while
searching with e.g. a russian layout.
Before, when looking for a matching user key binding, we only
matched *symbols*.
This means that the physical keys that generate a specific key binding
is layout dependent. What's worse, it may not even be possible to
generate the key binding at all.
Russian is one such layout, where all the "normal" (us) symbols are
replaced.
By using raw key codes, we can get around this - the key code has a
direct mapping to the physical key.
However, matching raw key codes **only** doesn't always make sense
either. For now, match **both** symbols _and_ key codes. Symbols take
precedence.
TODO: we might have to make this configurable _per binding_.
Note: 'search' mode still uses mostly hardcoded shortcuts that still
have this problem (i.e. ctrl+g doesn't work with a russian layout).
This adds an undocumented 'tweak' section to footrc, with two new
options:
* delayed-render-lower
* delayed-render-upper
Both takes an integer value, representing the lower/upper timeout
values (in nano seconds) for delayed rendering.
This fixes an issue where we sometimes (depends on compositor?) tried
to signal a TIOCSWINSZ and failed. This caused us to log a misleading
error message.
This fixes an issue where an 'underline' cursor wasn't visible on
underlined text - the cursor was rendered first, and then shadowed by
the text underline.
Track whether app-sync updates were enabled or disabled while handling
the current chunk of PTMX data.
This fixes and issue where we called render_refresh() unnecessarily
under (at least) the following conditions:
* Application sent "BSU <data> ESU" in the *same* chunk. In this case
we never saw that app sync was enabled and triggered delayed
rendering as usual.
* Application sent ESU. While we had noticed app sync updates being
enabled in earlier PTMX reads, when it was disabled *in the current*
PTMX read, we treated it as if it had not been enabled at all.
This caused us to trigger delayed rendering.
Now we call render_refresh() directly from ESU, and detect the "flip
off" case in PTMX read and avoid triggering a delayed rendering.
The end result of all this is that each key press (for e.g. scrolling
in a pager application) went from two frames being rendered, to a
single frame.
This fixes an issue where we failed to restore the cursor correctly
when exiting from the alternate screen, if the client had sent escapes
to save the cursor position while inside the alternate screen.
This was because we used the *same* storage for saving the cursor
position through escapes, as for saving it when entering the alternate
screen.
Fix by using a custom variable dedicated to normal <--> alt screen
switching.
This way we:
* Don't have to call wl_display_get_fd() all the time
* No longer call fdm_del_no_close() even though the FD hasn't been
added to the FDM.
This fixes an issue where the fonts were rendered too small when the
output had fractional scaling.
For integral scaling, using the logical (scaled) DPI multiplied with
the scaling factor results in the same final DPI value as if we had
used the physical DPI.
But for fractional scaling, this works around the fact that the
compositor downscales the surface after we've rendered it.
Closes#5
Sway 1.4 is better than 1.2, in that we always have keyboard focus
when we get a keyboard_key() event.
That however is because it doesn't send keyboard_leave() on e.g. a TTY
switch.
Still, this is good enough - foot handles this and doesn't crash. We
are also able to process input without having to refocus the window.
And, Sway master (what will become Sway 1.5) has fixed this for real -
we now get a keyboard_leave() and pointer_leave() event on a TTY
switch. And the corresponding enter events when switching back.
