Automatic face setting based on contrast?

[Richard Stallman]

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  > I made this point in the above bug report, but there is no way to
  > style Emacs with 25-50 face definitions.  It is very hard to put an
  > exact number on this, as e.g. some faces are inherited and therefore
  > more important, but realistically speaking you need at least twice
  > that to have a somewhat decent coverage.

Is this something that could be fixed, in principle?  Could a theme
specify some faces manually, and then Emacs would adjust various other
faces automatically so as to contrast with some of those?

Currently, a face can inherit properties from another face.
Could there be a kind of contrast-inheritance where face A
is set automatically to contrast strongly with B, and contrast
somewhat with C and D?  Based on calculations on the RGB codes,
I imagine.

This would call for a bit of research, but if we got it to work,
specifying a good theme might become a lot easier.

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)