This is a more robust approach; we make a separate pass to figure
out information about the (harfbuzz) cluster for a sequence of glyphs,
and then map that sequence back to the original cell sequence, and
from there compute the total cell width for the run, then distribute
the glyphs across the run.
This should yield more sane results for bidi.
Fixup the x-position math; it was still wonky despite the
efforts in 5f2c905db8 and
af92265ffb
refs: #1570
refs: #1607
refs: #1563
This allows unicode_version to be respected again when rendering.
The updated emoji-presentation.sh script now highlights this slightly
better by putting `.` characters after the emoji; unicode version 14
emoji presentation will show the `.` in the 3rd column, while earlier
versions will show it in the 2nd column for glyphs that are sensitive
to the version.
refs: #1607
refs: #1563
The centos8 builds have been failing today, and it appears to
be because https://www.centos.org/centos-linux-eol/ happened
about 3 years early and the URLs in the image are hard-broken.
https://forums.centos.org/viewtopic.php?f=54&t=78708 has some
info on re-pointing them to a vault subdomain.
The "right" thing to do is to migrate to centos 8 stream, but
I don't see a centos stream docker image from centos.
This commit attempts the manual migration steps to stream.
Let's see how this goes.
This commit does two related things, from opposite ends of the spectrum:
* Sets the sticky bit on pid files and unix sockets to avoid tmpwatch
deleting them in cleanup scenarios
* Falls back to looking at the changed time if the filesystem doesn't
support reporting creation time when wezterm does its own liveness
and cleanup checks for unix domain sockets in the runtime dir
* Allow any wezterm instance to perform that cleanup
refs: #1601
with:
```
bidi_enabled = false,
bidi_direction = "RightToLeft",
```
lines are now rendered right-justified in the terminal.
I think there's still work to do on this, because the cluster
order seems weird to me, but it's hard for me to intuit how
this should really look.
refs: #784
* Re-export portable_pty::PtySize as it is available in public API
* Re-export portable_pty::{MasterPty, ChildKiller} as those are both implemented by public structs from wezterm-ssh
This commit refines bidi property handling:
* experimental_bidi has been split into two new configuration settings;
`bidi_enabled` (which controls whether the terminal performs implicit
bidi processing) and `bidi_direction` which specifies the base
direction and whether auto detection is enabled.
* The `Line` type can now store those bidi properties (they are actually
split across 3 bits representing enabled, auto-detection and
direction)
* The terminal now has a concept of active bidi properties and default
bidi properties
* The default properties are pulled from the wezterm configuration
* active bidi properties are potentially set via escape sequences,
BDSM (which sets bidi_enabled) and SCP (which sets bidi_direction).
We don't support the 2501 temporary dec private mode suggested by
the BIDI recommendation doc at this time.
* When creating new `Line`'s or clearing from the start of a `Line`, the
effective bidi properties are computed (from the active props,
falling back to default propr) and applied to the `Line`.
* When rendering the line, we now look at its bidi properties instead
of just the global config.
The default bidi properties are `bidi_enabled: false` and
`bidi_direction: LeftToRight` which corresponds to the typical
bidi-unaware mode of most terminals.
It is possible to live reload the config to change the effective
defaults, but note that they apply, by design, to new lines being
processed through the terminal. That means existing output is
left unaffected by a config reload, but subsequently printed lines
will respect it. Pressing CTRL-L or otherwise contriving to have
the running application refresh its display should cause the
refreshed display to update and apply the new bidi mode.
refs: #784
This reverts commit a189bb57c14ec2245f276a077fbe13a88622c1d7;
it turns out that we do need to send those bonus lines because
the sequence number available to the logic here doesn't account
for the actual last rendered sequence number on the client, and
in a bursty update situation we can skip or otherwise omit a
line range.
refs: #1597
Two problems:
* Need reordered_runs method to populate ranges based on
the reordered levels!
* Use reordered runs to get the *logical* bounds of those
runs and pass those to harfbuzz.
Now the text is ordered correctly, but the rendering advances
by the wrong amount for the reordered clusters and looks bad
unless experimental_pixel_positioning=true.
refs: #784
Introduce a new config knob called 'local_echo_threshold_ms' to let
users configure when the local echo prediction should kick in. The
default value is 100ms to retain the current behavior.
This commit is larger than it appears to due fanout from threading
through bidi parameters. The main changes are:
* When clustering cells, add an additional phase to resolve embedding
levels and further sub-divide a cluster based on the resolved bidi
runs; this is where we get the direction for a run and this needs
to be passed through to the shaper.
* When doing bidi, the forced cluster boundary hack that we use to
de-ligature when cursoring through text needs to be disabled,
otherwise the cursor appears to push/rotate the text in that
cluster when moving through it! We'll need to find a different
way to handle shading the cursor that eliminates the original
cursor/ligature/black issue.
* In the shaper, the logic for coalescing unresolved runs for font
fallback assumed LTR and needed to be adjusted to cluster RTL.
That meant also computing a little index of codepoint lengths.
* Added `experimental_bidi` boolean option that defaults to false.
When enabled, it activates the bidi processing phase in clustering
with a strong hint that the paragraph is LTR.
This implementation is incomplete and/or wrong for a number of cases:
* The config option should probably allow specifying the paragraph
direction hint to use by default.
* https://terminal-wg.pages.freedesktop.org/bidi/recommendation/paragraphs.html
recommends that bidi be applied to logical lines, not physical
lines (or really: ranges within physical lines) that we're doing
at the moment
* The paragraph direction hint should be overridden by cell attributes
and other escapes; see 85a6b178cf
and probably others.
However, as of this commit, if you `experimental_bidi=true` then
```
echo This is RTL -> عربي فارسی bidi
```
(that text was sourced from:
https://github.com/microsoft/terminal/issues/538#issuecomment-677017322)
then wezterm will display the text in the same order as the text
renders in Chrome for that github comment.
```
; ./target/debug/wezterm --config experimental_bidi=false ls-fonts --text "عربي فارسی ->"
LeftToRight
0 ع \u{639} x_adv=8 glyph=300 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
2 ر \u{631} x_adv=3.78125 glyph=273 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
4 ب \u{628} x_adv=4 glyph=244 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
6 ي \u{64a} x_adv=4 glyph=363 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
8 \u{20} x_adv=8 glyph=2 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
9 ف \u{641} x_adv=11 glyph=328 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
11 ا \u{627} x_adv=4 glyph=240 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
13 ر \u{631} x_adv=3.78125 glyph=273 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
15 س \u{633} x_adv=10 glyph=278 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
17 ی \u{6cc} x_adv=4 glyph=664 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
19 \u{20} x_adv=8 glyph=2 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
20 - \u{2d} x_adv=8 glyph=276 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
21 > \u{3e} x_adv=8 glyph=338 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
```
```
; ./target/debug/wezterm --config experimental_bidi=true ls-fonts --text "عربي فارسی ->"
RightToLeft
17 ی \u{6cc} x_adv=9 glyph=906 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
15 س \u{633} x_adv=10 glyph=277 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
13 ر \u{631} x_adv=4.78125 glyph=272 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
11 ا \u{627} x_adv=4 glyph=241 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
9 ف \u{641} x_adv=5 glyph=329 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
8 \u{20} x_adv=8 glyph=2 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
6 ي \u{64a} x_adv=9 glyph=904 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
4 ب \u{628} x_adv=4 glyph=243 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
2 ر \u{631} x_adv=5 glyph=273 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
0 ع \u{639} x_adv=6 glyph=301 wezterm.font(".Geeza Pro Interface", {weight="Regular", stretch="Normal", italic=false})
/System/Library/Fonts/GeezaPro.ttc index=2 variation=0, CoreText
LeftToRight
0 \u{20} x_adv=8 glyph=2 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
1 - \u{2d} x_adv=8 glyph=480 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
2 > \u{3e} x_adv=8 glyph=470 wezterm.font("Operator Mono SSm Lig", {weight="DemiLight", stretch="Normal", italic=false})
/Users/wez/.fonts/OperatorMonoSSmLig-Medium.otf, FontDirs
;
```
refs: https://github.com/wez/wezterm/issues/784
In order to support RTL/BIDI, wezterm needs a bidi implementation. I
don't think a well-conforming rust implementation exists today; what I
found were implementations that didn't pass 100% of the conformance
tests.
So I decided to port "bidiref", the reference implementation of the UBA
described in http://unicode.org/reports/tr9/ to Rust.
This implementation focuses on conformance: no special measures have
been taken to optimize it so far, with my focus having been to ensure
that all of the approx 780,000 test cases in the unicode data for
unicode 14 pass. Having the tests passing 100% allows for making
performance improvements with confidence in the future.
The API isn't completely designed/fully baked. Until I get to hooking
it up to wezterm's shaper, I'm not 100% sure exactly what I'll need.
There's a good discussion on API in
https://github.com/open-i18n/rust-unic/issues/273 that suggests omitting
"legacy" operations such as reordering. I suspect that wezterm may
actually need that function to support monospace text layout in some
terminal scenarios, but regardless: reordering is part of the
conformance test suite so it remains a part of the API.
That said: the API does model the major operations as separate
phases, so you should be able to pay for just what you use:
* Resolving the embedding levels from a paragraph
* Returning paragraph runs of those levels (and their directions)
* Returning the whitespace-level-reset runs for a line-slice within the
paragraph
* Returning the reordered indices + levels for a line-slice within the
paragraph.
refs: https://github.com/wez/wezterm/issues/784
refs: https://github.com/kas-gui/kas-text/issues/20
