[cairo] Spot colors (and CMYK)

[ecir hana]

On Sun, Feb 21, 2010 at 1:48 AM, Chris Murphy <lists at colorremedies.com> wrote:
>
> I'm not saying you always need a profile. But such colors do need XYZ or LAB (or spectral if we look forward) metadata associated with them. Further, I propose we could also use ink opacity information.

You know me, I couldn't care less about alternative definition of a
spot color. If I was up to me, all would be random - so you could
easily distinguish between them :). But what I try to do is to
understand what Cairo needs to ask a user for. For now, for CMYK and
RGB you need to supply a profile and for spots a LAB triple? And I
know that in lcms you can create a transform from one profile to
another but I don't know what to do if I have just a LAB triple. And
then you say "ink opacity" - where, as a user, am I supposed to get
such info?