[metapost] rfc: consistent color values

[Jens-Uwe Morawski]

Am Freitag, den 08.04.2005, 20:18 +0200 schrieb Boguslaw Jackowski:

> What about controlling this behavior by a variable, say, `truecolors',
> similarly to the controlling of bounding boxes usin `truecorners'? 
> For example:
>    truecolors=0 -- current behavior
>    truecolors=1 -- colors are reduced to teh interval [0,1]
>                    prior to the shipping the picture to PostScript
>    truecolors=2 -- actual colors are shipped to PostScript

It's ok to me to have variables that control the behaviour,
but we shouldn't mix here two different things in one control
variable. Therefore we should have two variables: one that controls
the addto stage and one the shipout stage.

Additionally, it must be possible to change the behaviour for
each addto

addto ... withcolor (-1,-2,-3) ; % truncated color
begingroup
  interim truecolors:=1 ;
  addto ... withcolor (-1,-2,-3) ; % not truncated color ;
endgroup

j.