This commit is quite large because it's fairly interconnected and can't
be split up in a logical way. The main part of this commit is that alpha
blending is now always done in the Display P3 color space, and depending
on the configured `window-colorspace` colors will be converted from sRGB
or assumed to already be Display P3 colors. In addition, a config option
`text-blending` has been added which allows the user to configure linear
blending (AKA "gamma correction"). Linear alpha blending also applies to
images and makes custom shaders receive linear colors rather than sRGB.
In addition, an experimental option has been added which corrects linear
blending's tendency to make dark text look too thin and bright text look
too thick. Essentially it's a correction curve on the alpha channel that
depends on the luminance of the glyph being drawn.
This sets the stage for dynamically adjusting the sizes of fallback
fonts based on the primary font's face metrics. It also removes a lot of
unnecessary work when loading fallback fonts, since we only actually use
the metrics based on the parimary font.
This is achieved by rendering to an alpha-only context rather than a
normal single-channel context, and adjusting the brightness at which
coretext thinks it's drawing the glyph, which affects how it applies
font smoothing (which is what `font-thicken` enables).
\+ much more flexible syntax and lenient parser
\+ allows comma-separated list as a single config value
This allows, e.g. `cv01 = 2` to select the second variant of `cv01`.
Resolves#3128
Parser could probably be a little smaller than it is- would be a lot
cleaner with the labeled switch continue pattern from Zig 0.14. Maybe
should've put it in its own file too...
I spent *much* too long trying to test this with `cv01` with
[monaspace](https://github.com/githubnext/monaspace) before realizing
that the README refers to v1.2 but the latest released version (and
hence the one I had installed) was v1.101 -- I installed the v1.2
version and tested with both CoreText and HarfBuzz and successfully set
`cv01 = 2` and got the expected result.
Feel free to make any stylistic changes you feel necessary before
merging.
+ much more flexible syntax and lenient parser
+ allows comma-separated list as a single config value
This allows, e.g. `cv01 = 2` to select the second variant of `cv01`.
macOS bitmap-only fonts are a poorly documented format, which are often
distributed as `.dfont` or `.dfon` files. They use a 'bhed' table in
place of the usual 'head', but the table format is byte-identical, so
enabling the use of bitmap-only fonts only requires us to properly fetch
this table while calculating metrics.
ref: https://fontforge.org/docs/techref/bitmaponlysfnt.html
Reverts #3550 for obvious reasons, and may close issue #2168 because
this should now mean that bitmap fonts are properly supported under both
font backends due to #3837 - unless `otb` fonts are still not properly
supported under FreeType (they are not supported under CoreText because
CoreText does not know how to handle them).
I tested this change with the `.dfont` distribution of
[Cozette](https://github.com/slavfox/Cozette) v1.25.2 and saw no visual
issues.
macOS bitmap-only fonts are a poorly documented format, which are often
distributed as `.dfont` or `.dfon` files. They use a 'bhed' table in
place of the usual 'head', but the table format is byte-identical, so
enabling the use of bitmap-only fonts only requires us to properly fetch
this table while calculating metrics.
ref: https://fontforge.org/docs/techref/bitmaponlysfnt.html
The original version had issues converting properly and caused broken
glyphs. This version tries to be as simple as possible in order to make
it easy to understand. I haven't measured the performance but in
practice this will only happen during the first render of the glyph
after a face change (i.e. during launch or when changing font size).
We do not currently support bitmap fonts in a real capacity, and they
often are missing some tables which we currently rely on for metrics,
and we don't handle the metrics calculations failing gracefully right
now.
Annotate the node count of all uses of z2d `StaticPath` to verify
correctness, adjusted the size of a couple which were oversized, and
changed all painter calls that take node slices from `StaticPath`s to
use the slice from the wrapped `ArrayList` so that we don't include any
potentially `undefined` nodes at the end of the list, which I think was
causing a crash before.
Introduces static path methods and a reworked context API that makes
things generally cleaner.
This update incidentally fixed a bug we had before where the corner
triangle shade characters were drawn solid rather than medium shade.
Subsumes #2580 (which has multiple conflicts with main due to recent
changes to metrics); I figured it'd be easier to just implement it this
way.
#2580 claimed to solve #2487 but I don't think it really does- ideally
we can think of a good way to configure each individual cursor type, but
I don't wanna just do something ad hoc and add a bunch of config keys
blindly so I limited the scope of this.
Unicode 16 added "Separated Block Quadrants" from CP 0x0x1CC21 through
0x1CC2F:
To test, use the following command:
```
printf "\U0001CC21\U0001CC22\U0001CC23\U0001CC24\U0001CC25\U0001CC26\U0001CC27\U0001CC28\U0001CC29\U0001CC2A\U0001CC2B\U0001CC2C\U0001CC2D\U0001CC2E\U0001CC2F\n"
```
Which should look like this:
cc @qwerasd205 @rockorager
- Simplifies and clarifies the math for how the bounding box for
rendered glyphs is computed
- Reduces margin from 2px between glyphs to 1px by only padding the
bottom and right side of each glyph
- Avoids excessive padding to glyph box when font thicken is enabled or
when using a synthetic bold (it was previously 4x as much padding as
necessary in some cases)
Variable font init used to just select the first available predefined
instance, if there were any, which is often not desirable- using
createFontDescriptorFromData instead of createFontDescritorsFromData
ensures that the default variation config is selected. In the future we
should probably allow selection of predefined instances, but for now
this is the correct behavior.
I found this bug when adding the metrics calculation test case for
CoreText, hence why fixing it is part of the same commit.
Unify grid metrics calculations by relying on shared logic mostly based
on values directly from the font tables, this deduplicates a lot of code
and gives us more control over how we interpret various metrics.
Also separate metrics for underlined, strikethrough, and overline
thickness and position, and box drawing thickness, so that they can
individually be adjusted as the user desires.
