[MPEG-OTSPEC] Colour fonts and PDF

[William_J_G Overington]

What is the current situation regarding colour fonts and PDF (Portable 
Document Format) please?

I seem to remember that some years ago there was something - possibly in 
this list - about somebody having produced an experimental program that 
had input of text and the program produced a PDF document, without any 
alteration being needed to the PDF specification, the  PDF document 
being produced by extracting the layers from the COLR/CPAL font and 
producing a multilayer PDF document, one layer for each colour. Has that 
idea been developed and become mainstream please?

Producing an end result like the long-possible facility of using a set 
of fonts and manually combining several layers, one for each font, as in 
the following example.

http://www.users.globalnet.co.uk/~ngo/mosaic3.PDF

William Overington

Friday 5 February 2021