Fixes#668
We were previously only checking the first font result in the search.
This also fixes our CoreText scoring algorithm to prioritize faces that
have the codepoint we're searching for.
This is a weird one. By using intCast on the `idx` I am periodically
getting a panic on index out of bounds where the index is larger than
FontIndex can possibly be. Very strange!
I tried to just remove intCasts and believe it or not that worked.
Previously, `cat /dev/urandom` would trigger the issue in seconds and
now I've had it running 20+ minutes without the issue.
The additional `if` check is just a safety mechanism
Fixes#143
There were multiple issues with the previous calculation. First, we
expected dash width COULD be negative and protected against it, but our
dash width calculation type was unsigned! With the proper font metrics,
this led to an underflow safey panic.
Second, as part of the dash width calculation, we are tryign to downstep
the size of the gaps so we can try to fit dashes within a cell. But we
were not using those adjusted gap sizes. With the proper font metrics,
this could lead to an assertion failure seen in #143.
This fixes the calculations. They produce the same numbers, but do so in
a more Zig-idiomatic way while fixing the above two issues.
When font shaping grapheme clusters, we erroneously used the font index
of a font that only matches the first codepoint in the cell. This led to the
combining characters being [usually] unknown and rendering as boxes.
For a grapheme, we must find a font face that has a glyph for _all codepoints_
in the grapheme.
This also fixes an issue where we now properly render the unicode replacement
character if we can't find a font satisfying a codepoint.
* font: disable default font features for Menlo and Monaco
Both of these fonts have a default ligature on "fi" which makes terminal
rendering super ugly. The easiest thing to do is special-case these
fonts and disable ligatures. It appears other terminals do the same
thing.
Fontconfig in particular appears unsafe to initialize multiple times.
Font discovery is a singleton object in an application and only ever
accessed from the main thread so we can work around this by only
initializing and caching the font discovery mechanism exactly once on
the app singleton.
