CMYK data describes which inks a printer should use to print a color.
If a screen should display a color that's supposed to look similar
to what the printer produces, it results in a color very different
to what Color::from_cmyk() produces. (It's also printer-dependent.)
There are many ICC profiles describing printing processes. It doesn't
matter too much which one we use -- most of them look somewhat
similar, and they all look dramatically better than Color::from_cmyk().
This patch adds a function to download a zip file that Adobe offers
on their web site. They even have a page for redistribution:
https://www.adobe.com/support/downloads/iccprofiles/icc_eula_win_dist.html
(That one leads to a broken download though, so this downloads the
end-user version.)
In case we have to move off this download at some point, there are also
a whole bunch of profiles at https://www.color.org/registry/index.xalter
that "may be used, embedded, exchanged, and shared without restriction".
The adobe zip contains a whole bunch of other useful and fun profiles,
so I went with it.
For now, this only unzips the USWebCoatedSWOP.icc file though, and
installs it in ${CMAKE_BINARY_DIR}/Root/res/icc/Adobe/CMYK/. In
Serenity builds, this will make it to /res/icc/Adobe/CMYK in the
disk image. And in lagom build, after #23016 this is the
lagom res staging directory that tools can install via
Core::ResourceImplementation. `pdf` and `MacPDF` already do that,
`TestPDF` now does it too.
The final piece is that LibPDF then loads the profile from there
and uses it for DeviceCMYK color conversions.
(Doing file access from the bowels of a library is a bit weird,
especially in a system that has sandboxing built in. But LibGfx does
that in FontDatabase too already, and LibPDF uses that, so it's not a
new problem.)
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