Release 1.8.0
Grapheme shaping
----------------
This release adds _experimental, opt-in_ support for grapheme cluster
segmentation and grapheme shaping.
(note: several of the examples below may not render correctly in your
browser, viewer or editor).
Grapheme cluster segmentation is the art of splitting up text into
grapheme clusters, where a cluster may consist of more than one
Unicode codepoint. For example, 🙂 is a single codepoint, while 👩🏽🚀
consists of 4 codepoints (_Woman_ + _Medium skin tone_ + _Zero width
joiner_ + _Rocket_). The goal is to _cluster_ codepoints belonging to
the same grapheme in the same cell in the terminal.
Previous versions of foot implemented a simple grapheme cluster
segmentation technique that **only** handled zero-width
codepoints. This allowed us to cluster combining characters, like q́
(_q_ + _COMBINING ACUTE ACCENT_).
Once we have a grapheme cluster, we need to _shape_ it.
Combining characters are simple: they are typically rendered as
multiple glyphs layered on top of each other. This is why previous
versions of foot got away with it without any actual text shaping
support.
Beyond that, support from the font library is needed. Foot now depends
on fcft-2.4, which added support for grapheme and text shaping. When
rendering a cell, we ask the font library: give us the glyph(s) for
this sequence of codepoints.
Fancy emoji sequences aside, using libutf8proc for grapheme cluster
segmentation means **improved correctness**.
For full support, the following is required:
* fcft compiled with HarfBuzz support
* foot compiled with libutf8proc support
* `tweak.grapheme-shaping=yes` in `foot.ini`
If `tweak.grapheme-shaping` has **not** been enabled, foot will
neither use libutf8proc to do grapheme cluster segmentation, nor will
it use fcft’s grapheme shaping capabilities to shape combining
characters.
This feature is _experimental_ mostly due to the “wcwidth” problem;
how many cells should foot allocate for a grapheme cluster? While the
answer may seem simple, the problem is that, whatever the answer is,
the client application **must** come up with the **same**
answer. Otherwise we get cursor synchronization issues.
In this release, foot simply adds together the `wcwidth()` of all
codepoints in the grapheme cluster. This is equivalent to running
`wcswidth()` on the entire cluster. **This is likely to change in the
future**.
Finally, note that grapheme shaping is not the same thing as text (or
text run) shaping. In this version, foot only shapes individual
graphemes, not entire text runs. That means e.g. ligatures are **not**
supported.
Added
-----
* Support for DECSET/DECRST 2026, as an alternative to the existing
"synchronized updates" DCS sequences
(https://codeberg.org/dnkl/foot/issues/459).
* `cursor.beam-thickness` option to `foot.ini`
(https://codeberg.org/dnkl/foot/issues/464).
* `cursor.underline-thickness` option to `foot.ini`
(https://codeberg.org/dnkl/foot/issues/524).
* Unicode 13 characters U+1FB70 - U+1FB8B to list of box drawing
characters rendered by foot itself (rather than using font glyphs)
(https://codeberg.org/dnkl/foot/issues/471).
* Dedicated `[bell]` section to config, supporting multiple actions
and a new `command` action to run an arbitrary command.
(https://codeberg.org/dnkl/foot/pulls/483)
* Dedicated `[url]` section to config.
* `[url].protocols` option to `foot.ini`
(https://codeberg.org/dnkl/foot/issues/531).
* Support for setting the full 256 color palette in foot.ini
(https://codeberg.org/dnkl/foot/issues/489)
* XDG activation support, will be used by `[bell].urgent` when
available (falling back to coloring the window margins red when
unavailable) (https://codeberg.org/dnkl/foot/issues/487).
* `ctrl`+`c` as a default key binding; to cancel search/url mode.
* `${window-title}` to `notify`.
* Support for including files in `foot.ini`
(https://codeberg.org/dnkl/foot/issues/555).
* `ENVIRONMENT` section in **foot**(1) and **footclient**(1) man pages
(https://codeberg.org/dnkl/foot/issues/556).
* `tweak.pua-double-width` option to `foot.ini`, letting you force
_Private Usage Area_ codepoints to be treated as double-width
characters.
* OSC 9 desktop notifications (iTerm2 compatible).
* Support for LS2 and LS3 (locking shift) escape sequences
(https://codeberg.org/dnkl/foot/issues/581).
* Support for overriding configuration options on the command line
(https://codeberg.org/dnkl/foot/issues/554,
https://codeberg.org/dnkl/foot/issues/600).
* `underline-offset` option to `foot.ini`
(https://codeberg.org/dnkl/foot/issues/490).
* `csd.button-color` option to `foot.ini`.
* `-Dterminfo-install-location=disabled|<custom-path>` meson command
line option (https://codeberg.org/dnkl/foot/issues/569).
Changed
-------
* [fcft](https://codeberg.org/dnkl/fcft): required version bumped from
2.3.x to 2.4.x.
* `generate-alt-random-writes.py --sixel`: width and height of emitted
sixels has been adjusted.
* _Concealed_ text (`\E[8m`) is now revealed when highlighted.
* The background color of highlighted text is now adjusted, when the
foreground and background colors are the same, making the
highlighted text legible
(https://codeberg.org/dnkl/foot/issues/455).
* `cursor.style=bar` to `cursor.style=beam`. `bar` remains a
recognized value, but will eventually be deprecated, and removed.
* Point values in `line-height`, `letter-spacing`,
`horizontal-letter-offset` and `vertical-letter-offset` are now
rounded, not truncated, when translated to pixel values.
* Foot’s exit code is now -26/230 when foot itself failed to launch
(due to invalid command line options, client application/shell not
found etc). Footclient’s exit code is -36/220 when it itself fails
to launch (e.g. bad command line option) and -26/230 when the foot
server failed to instantiate a new window
(https://codeberg.org/dnkl/foot/issues/466).
* Background alpha no longer applied to palette or RGB colors that
matches the background color.
* Improved performance on compositors that does not release shm
buffers immediately, e.g. KWin
(https://codeberg.org/dnkl/foot/issues/478).
* `ctrl + w` (_extend-to-word-boundary_) can now be used across lines
(https://codeberg.org/dnkl/foot/issues/421).
* Ignore auto-detected URLs that overlap with OSC-8 URLs.
* Default value for the `notify` option to use `-a ${app-id} -i
${app-id} ...` instead of `-a foot -i foot ...`.
* `scrollback-*`+`pipe-scrollback` key bindings are now passed through
to the client application when the alt screen is active
(https://codeberg.org/dnkl/foot/issues/573).
* Reverse video (`\E[?5h`) now only swaps the default foreground and
background colors. Cells with explicit foreground and/or background
colors remain unchanged.
* Tabs (`\t`) are now preserved when the window is resized, and when
copying text (https://codeberg.org/dnkl/foot/issues/508).
* Writing a sixel on top of another sixel no longer erases the first
sixel, but the two are instead blended
(https://codeberg.org/dnkl/foot/issues/562).
* Running foot without a configuration file is no longer an error; it
has been demoted to a warning, and is no longer presented as a
notification in the terminal window, but only logged on stderr.
Deprecated
----------
* `bell` option in `foot.ini`; set actions in the `[bell]` section
instead.
* `url-launch` option in `foot.ini`; use `launch` in the `[url]`
section instead.
* `jump-label-letters` option in `foot.ini`; use `label-letters` in
the `[url]` section instead.
* `osc8-underline` option in `foot.ini`; use `osc8-underline` in the
`[url]` section instead.
Removed
-------
* Buffer damage quirk for Plasma/KWin.
Fixed
-----
* `generate-alt-random-writes.py --sixel` sometimes crashing,
resulting in PGO build failures.
* Wrong colors in the 256-color cube
(https://codeberg.org/dnkl/foot/issues/479).
* Memory leak triggered by “opening” an OSC-8 URI and then resetting
the terminal without closing the URI
(https://codeberg.org/dnkl/foot/issues/495).
* Assertion when emitting a sixel occupying the entire scrollback
history (https://codeberg.org/dnkl/foot/issues/494).
* Font underlines being positioned below the cell (and thus being
invisible) for certain combinations of fonts and font sizes
(https://codeberg.org/dnkl/foot/issues/503).
* Sixels with transparent bottom border being resized below the size
specified in _”Set Raster Attributes”_.
* Fonts sometimes not being reloaded with the correct scaling factor
when `dpi-aware=no`, or `dpi-aware=auto` with monitor(s) with a
scaling factor > 1 (https://codeberg.org/dnkl/foot/issues/509).
* Crash caused by certain CSI sequences with very large parameter
values (https://codeberg.org/dnkl/foot/issues/522).
* Rare occurrences where the window did not close when the shell
exited. Only seen on FreeBSD
(https://codeberg.org/dnkl/foot/issues/534)
* Foot process(es) sometimes remaining, using 100% CPU, when closing
multiple foot windows at the same time
(https://codeberg.org/dnkl/foot/issues/542).
* Regression where `<mod>+shift+tab` always produced `\E[Z` instead of
the correct `\E[27;<mod>;9~` sequence
(https://codeberg.org/dnkl/foot/issues/547).
* Crash when a line wrapping OSC-8 URI crossed the scrollback wrap
around (https://codeberg.org/dnkl/foot/issues/552).
* Selection incorrectly wrapping rows ending with an explicit newline
(https://codeberg.org/dnkl/foot/issues/565).
* Off-by-one error in markup of auto-detected URLs when the URL ends
in the right-most column.
* Multi-column characters being cut in half when resizing the
alternate screen.
* Restore `SIGHUP` in spawned processes.
* Text reflow performance (https://codeberg.org/dnkl/foot/issues/504).
* IL+DL (`CSI Ps L` + `CSI Ps M`) now moves the cursor to column 0.
* SS2 and SS3 (single shift) escape sequences behaving like locking
shifts (https://codeberg.org/dnkl/foot/issues/580).
* `TEXT`+`STRING`+`UTF8_STRING` mime types not being recognized in
clipboard offers (https://codeberg.org/dnkl/foot/issues/583).
* Memory leak caused by custom box drawing glyphs not being completely
freed when destroying a foot window instance
(https://codeberg.org/dnkl/foot/issues/586).
* Crash in scrollback search when current XKB layout is missing
_compose_ definitions.
* Window title not being updated while window is hidden
(https://codeberg.org/dnkl/foot/issues/591).
* Crash on badly formatted URIs in e.g. OSC-8 URLs.
* Window being incorrectly resized on CSD/SSD run-time changes.
Contributors
------------
* [r\_c\_f](https://codeberg.org/r_c_f)
* [craigbarnes](https://codeberg.org/craigbarnes)