This was a bit of a PITA to run down; the essence of the problem
was that the shaper was returning an x_advance of 0 for U+3000,
which caused wezterm's shaping layer to elide that glyph.
I eventually tracked down the x_advance to be the result of
scaling by an x_scale of 0, which in turn is the result of
harfbuzz not knowing the font size.
The critical portion of this diff is the line that advises
harfbuzz that the font has changed after we've applied the
font size.
The rest is just stuff to make it easier to debug and verify.
This:
```
printf "x\u3000x."
```
Now correctly renders on screen as "x x".
fixes: #1161
I noticed while reviewing the session recording for https://github.com/wez/wezterm/issues/1102
that wezterm reported:
```
2021-09-04T22:05:46.136Z WARN wezterm_term::terminalstate::performer > unknown unspecified CSI: "58::2::87::61::38m"
2021-09-04T22:05:46.138Z WARN wezterm_term::terminalstate::performer > unknown unspecified CSI: "58::2::87::61::38m"
```
Those extra double-colons aren't valid, and I think they're coming from
this terminfo file, so fix it up!
This will enable eg: a lua helper function to serialize keycodes to
assist in some key rebinding scenarios (see:
https://github.com/wez/wezterm/pull/1091#issuecomment-910940833 for the
gist of it) but also makes it a bit easier to write unit tests for key
encoding so that situations like those in #892 are potentially less
likely to occur in the future.
If a cell contained a ligature, the math used to track where the
next quad was going to be placed could lose consistency with
the cluster/shaping information and result in offset glyphs.
This was most noticeable to me in tab titles in the tab bar;
my shell dotfiles append `-- something` to the title when a
command is launched, and the `--` is a ligature in my font.
I think I've also seen this mess up positioning in the notcurses
demo as well.
The solution is to take the cluster initial cell index rather
than trying to reverse engineer it from incomplete info.
A while back I made the line lengths lazily grown; the reduction
in memory was nice, and it helped with render performance for
really wide screens.
Unfortunately, it puts a bunch of reallocation into the hot path
of the parser and updating the terminal model when people run
the inevitable `cat giant-file.txt` benchmark.
This commit reinstates pre-allocating lines to match the physical
terminal width, and tweaks the code a bit to take advantage of
const Cell allocation and to avoid some clones (a really micro
optimization).
For simple graphemes, we can avoid subsequently calling
grapheme_column_width and cache that information in TeenyString.
Make blank TeenyString and Cell initializations const.
Terminal now maintains a sequence number that increments
for each Action that is applied to it.
Changes to lines are tagged with the current sequence number.
This makes it a bit easier to reason about when an individual
line has changed relative to some point in "time"; the consumer
of the terminal can sample the current sequence number and then
can later determine which lines have changed since that point
in time.
refs: https://github.com/wez/wezterm/issues/867
An implementation detail in wezterm is that it doesn't model
image placements as a separate entity; they are all bound to
the image cells in the terminal model.
The semantics of the kitty image protocol are that placements
are "permanent" wrt. overwriting a cell with text, except for
the explicit EraseInLine/EraseInDisplay sequences that are
used for clearing.
This commit takes a pass at implementing that semantic in
the wezterm data model.
refs: #986
This should give the shaper a better chance at using text
presentation in a run that mixes emoji with text and/or
uses presentation selectors.
It also exposes the presentation property to the shaper
so that it could potentially adjust its fallback strategy.
However, it doesn't do that here.
refs: https://github.com/wez/wezterm/issues/997
Make a distinction between default and selected presentation,
and account for that in the cell width.
Add a method to the cell that returns the effective presentation.
refs: https://github.com/wez/wezterm/issues/997
These modifiers have the effect of forcing us to consider the grapheme
as being either a single cell (VS15) or two cells (VS16) in the
terminal model.
These don't affect font choice as wezterm doesn't know whether a given
font in the fallback has a textual vs. an emoji version of a given
glyph, or whether a later font in the fallback has one or the other
because we can't know until we fall back, and that has a very high
cost--we perform fallback asynchronously in another thread because
of its high cost.
Depending on the selected glyph, it may or may not render as double
wide.
refs: #997
Since we can now mutate individual frames, we need to avoid
falsely caching across a change; switch from using (image_id, frame_idx)
to frame_hash.
refs: #986
Adds a use_image feature to termwiz that enables an optional
dep on the image crate. This in turn allows decoding of animation
formats (gif, apng) from file data, but more crucially, allows
modeling animation frames at the termwiz layer, which is a pre-req
for enabling kitty img protocol animation support.
refs: #986
I noticed when running the notcurses demo that we're spending a
decent amount of time decoding png data whenever we need to
re-do the texture atlas.
Let's avoid that by allowing for ImageData at the termwiz layer
to represent both the image file format and decoded rgba8 data.
This commit is a bit muddy and also includes some stuff to try
to delete placements from the model. It's not perfect by any
means--more expensive than I want, and there's something funky
that causes a large number of images to build up during some
phases of the demo.
refs: #986
This isn't complete; many of the placement options are not supported,
and the status reporting is missing in a number of cases, including
querying/probing, and shared memory objects are not supported yet.
However, this commit is sufficient to allow the kitty-png.py script
(that was copied from
https://sw.kovidgoyal.net/kitty/graphics-protocol/#a-minimal-example)
to render a PNG in the terminal.
This implementation routes the basic image display via the same
code that we use for iterm2 and sixel protocols, but it isn't
sufficient to support the rest of the placement options allowed
by the spec.
Notably, we'll need to add the concept of image placements to
the data model maintained by the terminal state and find a way
to efficiently manage placements both by id and by a viewport
range.
The renderer will need to manage separate quads for placements
and order them by z-index, and adjust the render phases so that
images can appear in the correct plane.
refs: #986
This teaches termwiz to recognize and encode the APC
sequences used by the kitty image protocol.
This doesn't include support for animations, just the
transmit, placement and delete requests.
refs: #986
These were parsed but swallowed. This commit expands the transitions
to be able to track the APC start, data and end and then adds
an `apc_dispatch` method to allow capturing APC sequences.
APC sequences are used in the kitty image protocol.
refs: #986
This commit hooks up DECRQM so that we can report that we implement
synchronized updates, and then refines the code that manages sending
data to the terminal model; the first cut at synchronized updates
was a bit simplistic, and now we make a point of "flushing" pending
actions when we start a sync point, and again as soon as we release
the sync point.
This smooths out the jaggies around the orca that I mentioned in
dcbbda7702
and while testing this, I realized that recent parser changes had
mangled processing bundled dec private mode sequences where multiple
modes were specified in the same overall escape sequence. I've
added the missing unit test case for this and made that work again.
refs: https://github.com/wez/wezterm/issues/955
refs: https://github.com/wez/wezterm/issues/882
