Using the frame callback works most of the time, but e.g. Sway doesn’t
call it while the window is hidden, and thus prevents us from updating
the title in e.g. stacked views.
This patch uses a timer FD instead. We store a timestamp from when the
title was last updated. When the application wants to update the
title, we first check if we already have a timer running, and if so,
does nothing.
If no timer is running, check the timestamp. If enough time has
passed, update the title immediately.
If not, instantiate a timer and wait for it to trigger.
Set the minimum time between two updates to ~8ms (twice per frame, for
a 60Hz output, and ~once per frame on a 120Hz output).
Closes#591
tllists are great when dealing with dynamically changing lists. They
are also very easy to use when building lists/arrays where the final
size is unknown.
However, this ease of use comes at a price: code size. tll-macros
expand to a lot of code.
Since things in the config are static, once the config has been
loaded, using tllists for configuration data structures doesn’t make
much sense.
This patch replaces nearly all tllists used by the configuration, with
dynamically allocated arrays.
When printing a character to a cell, we copy the current VT state’s
attributes to the cell. And then clear the ‘clean’ bit.
But the ‘clean’ bit is part of the VT state, and is *always*
zero. Thus there’s no need to explicitly clear it right after copying
the VT state.
This is a fairly new XTerm extension. The reply is on the format:
DCS > | text ST
XTerm replies with ‘text’ = “XTerm(366)”.
Foot replies with ‘text’ = “foot(1.6.4)”
Closes#359
There's no mention of SS0 or SS1 functions in ECMA-48 or ECMA-35.
0x0E/0x0F are SO/SI (Shift In/Out) in "7-bit environments" or LS0/LS1
(Locking Shift 0/1) in "8-bit environments". The former is the one
that applies to foot, since it generally follows "7-bit" conventions
due to its use of UTF-8.
See also: ECMA-35 §7.2 and §9.2.
Allow any configuration option to be overridden with -o/--override
'section.key=value' arguments, as suggested in #554
update completitions for override
slight refactoring to ease footclient support
This commit also renames the term_set_single_shift_ascii_printer()
function to term_single_shift(), since the former is overly verbose
and not really even accurate.
Writing a sixel on top of an already existing sixel currently has the
following limitations in foot:
* The parts of the first sixel that is covered by the new sixel are
removed, completely. Even if the new sixel has transparent
areas. I.e. writing a transparent sixel on top of another
sixel *replaces* the first sixel with the new sixel, instead of
layering them on top of each other.
* The second sixel erases the first sixel cell-wise. That is, a sixel
whose size isn’t a multiple of the cell dimensions will leave
unsightly holes in the first sixel.
This patch takes care of both issues.
The first one is actually the easiest one: all we need to do is
calculate the intersection, and blend the two images. To keep things
relatively simple, we use the pixman image from the *new* image, and
use the ‘OVER_REVERSE’ operation to blend the new image over the old
one.
That is, the old image is still split into four tiles (top, left,
right, bottom), just like before. But instead of throwing away the
fifth middle tile, we blend it with the new image. As an optimization,
this is only done if the new image has transparency (P1=1).
The second problem is solved by detecting when we’re erasing an area
from the second image that is larger than the new image. In this case,
we enlarge the new image, and copy the old image into the new one.
Finally, when we enlarge the new image, there may be areas in the new
image that is *not* covered by the old image. These areas are made
transparent.
The end result is:
* Each cell is covered by at *most* 1 sixel image. I.e. the total
numbers of sixels are finite. This is important for the ‘mpv
--vo=sixel’ use case - we don’t want to end up with thousands of
sixels layered on top of each other.
* Writing an opaque sixel on top of another sixel has _almost_ zero
performance impact. Especially if the two sixels have the same size,
so that we don’t have to resize the new image. Again, important for
the ‘mpv --vo=sixel’ use case.
Closes#562
These sequences are supposed to affect the next printable ASCII
character and then reset to the previous character set, but before
this commit they were behaving like locking shifts.
If the cursor is already at the right edge, our logic that checked for
non-empty cells failed; it didn’t check the current cell.
Fix by initializing ‘emit_tab_char’ to true/false, depending on the
contents of the current cell.
TAB (\t) move the cursor to the next tab stop. That’s it, according to
the specification.
However, many terminal emulators try to keep tabs in the grid, to be
able to e.g. copy them. That is, copying a text chunk containing tabs
should result in tabs being pasted, not spaces.
In order to do that, we need to print a tab character to the grid. To
improve text reflow of tabs, we also print spaces to the subsequent
cells, up until (but not including) the next tab stop.
However, we can only do this if all the cells between the cursor and
the next tab stop are empty, since (obviously), we cannot overwrite
pre-existing characters.
Finally, while some fonts render tabs as spaces (i.e. an empty glyph),
some use a glyph representing “unprintable” characters, or
similar. Thus, we need to exclude cells with tab characters when
rendering.
