Hi,
The Skin Tone modifier is working as a combining character,
so it must be handled at the level higher than FreeType.
FreeType does not return the image of "À" (U+00C0) from
the sequence "A" + "`" (U+0041, U+0300) , even if the
specified font has a precomposed glyph which is accessible
from GSUB table.
I guess HarfBuzz has already supported the skin tone modifier,
according to here:
https://ja.overleaf.com/learn/latex/Articles/An_overview_of_technologies_supporting_the_use_of_colour_emoji_fonts_in_LaTeX#Exploring_HarfBuzz
Regards,
mpsuzuki
On 2022/01/21 18:17, Werner LEMBERG wrote:
We would like to implement the colored font feature of freetype to
manage colored emoji.
We already have a POC with colored emoji, but we have seen that some
of the glyph in our font (Segoe UI Emoji) are associated with a skin
tone modifier base on Fitzpatrick scale.
We don't really know how to manage this.
Is this something managed by the freetype library?
I'm not an expert, but as far as I know this has to be handled at a
higher level by using Emoji ZWJ Sequences.
https://unicode.org/emoji/charts/emoji-zwj-sequences.html
Dominik, can you give more information?
Werner
