Coloured Punctuation and Annotation

[Peter Constable via Unicode]

Michael, your two-tone effect can easily be added into your first font using COLR and CPAL tables, so that the one font can support a monochrome rendering that uses glyphs in which the swirls are fused with the letters, and can also support a poly-chrome rendering in which those glyphs are decomposed into separate glyphs that get layered on top of one another in an order you specify with different RGBA colours.


Peter

-----Original Message-----
From: Unicode [mailto:unicode-bounces at unicode.org] On Behalf Of Michael Everson
Sent: Thursday, April 6, 2017 5:41 AM
To: unicode Unicode Discussion <unicode at unicode.org>
Subject: Re: Coloured Punctuation and Annotation


> On 6 Apr 2017, at 05:41, Richard Wordingham <richard.wordingham at ntlworld.com> wrote:
> 
> On Thu, 6 Apr 2017 01:11:09 +0100
> Michael Everson <everson at evertype.com> wrote:
> 
>> On 5 Apr 2017, at 22:48, Richard Wordingham 
>> <richard.wordingham at ntlworld.com> wrote:
>> 
>>> I tried to read it from UTS#51 ‘Unicode Emoji', which is not part of TUS, but I couldn't deduce that a font that enables U+10B99 PSALTER PAHLAVI SECTION MARK to have exactly two (as opposed to none or four) red dots is in breach of the guidelines therein. 
>> 
>> Kindly explain how ANY font could do this.
> 
> Is this a trick question?

No. Here is an example of a font available in two variants. In one variant, all those grey swirls are fused to the letters, and it can all be printed in black or one colour ink. https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fcdn.myfonts.net%2Fs%2Faw%2Foriginal%2F255%2F0%2F131020.png&data=02%7C01%7Cpetercon%40microsoft.com%7Cd423eda2387c475363ef08d47ceb4b80%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636270797424696444&sdata=%2F64giVqctMwconsQVzFvIj7WPbOzNeQ%2F6npJUlIXaTc%3D&reserved=0 

There is also a second set of fonts included which separates the swirls from the letters, and those can be used in typesetting to get the two-colour effect you see here. That can’t really be done using standard encoding. You’d probably see IIVVOORRYY in the backing store for that word, with every other letter being set in the letter font and the swirl font. 

Emoji-style colour fonts use other mechanisms for colour.

Michael Everson