Re: NotoColorEmoji - loca table not found

[Hans Hagen <j.hagen@xs4all.nl>]

On 5/14/2021 6:33 PM, Adam Reviczky wrote:
> Hi Hans,
> 
> Yes, sorry about the error :).
> 
> Thanks for the explanation, will use lmtx for that, though probably best 
> just using another font (some mentioned on the list 
> https://www.mail-archive.com/ntg-context@ntg.nl/msg92800.html 
> <https://www.mail-archive.com/ntg-context@ntg.nl/msg92800.html> and 
> https://mailman.ntg.nl/pipermail/ntg-context/2020/098136.html 
> <https://mailman.ntg.nl/pipermail/ntg-context/2020/098136.html>) or svg 
> or metapost as I do not need it in colour.

I spend quite a bit of time looking into this (it's already a while ago 
when I implemented all this and color stuff in otf is a bit of a mess 
and evolving, so in retrospect it's probably better to wait a few years 
to see how that works out; the same for variable fonts ... hadr to deal 
with when there are not many fonts and fuzzy specs.)

Anyway, the problem is this: these png emoji are using palettes + masks 
and that combinaiton gives:

- with gm (gs) : white background
- with mutool  : black background
- with luatex  : a mess
- with lmtx    : what we want

now, testing all this takes a lot of time in mkiv because building the 
cache file takes time, so it's one of these moments i wonder if a modern 
machine would do better than my old but reliable machine. The outcome is 
that in mkiv one can do this:

\enabledirectives[backend.otfpng.method=lmtx]   % the real deal, slow
\enabledirectives[backend.otfpng.method=mutool] % black bg
\enabledirectives[backend.otfpng.method=gm]     % white bg, default

So, when you have a fast machine or a coffe break, you can use the lmtx 
method (can be configures in cont-loc.mkiv).

As manetioned, in lmtx it is done differently so no penalties there.

> I thought it would be easier via fonts but backtracking on the idea now 
> and maybe using something like this instead: 
> https://thenounproject.com/term/handshake/153516/ 
> <https://thenounproject.com/term/handshake/153516/>.
btw, some emoji fonts have both bw outlines and bitmap color, some use 
png (bloated), and microsoft fonts have efficient outline color (nice 
mechanism).

Hans

(who never uses emoji)


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                                           Hans Hagen | PRAGMA ADE
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