Hi Hans

I don't know if the latest beta already has the new code. But I can confirm, that there is still a difference between tikz-colors and context/metafun colors.

TikZ translates c=1,m=1 in (native) RGB, that is b=1, which is in some way correct.
ConTeXt translates c=1,m=1 in something I couldn't really define (perhaps sRGB or some other color profile) r=0.183... g=0.191... b=0.574... or in Web-Hex: #2e3092

or back to cmyk: c=.68, m=.67,k=.43 (which is blue with some key-value compared to TikZ with k=0)

So I think that TikZ and ConTeXt don't use the same color profile....

Hope it could help somewhat to solve my problem.

Thanks
Christian

PS.: New MWE with output.pdf attached.

\usemodule[tikz]
\usetypescript[palatino]
\setupbodyfont[palatino,40pt]
\starttext
\definecolor[mycola][c=1,m=1,y=0,k=0]
\definecolor[mycolb][c=0.5,m=0.5,y=0,k=0]
\definecolor[mycolc][c=0.25,m=0.25,y=0,k=0]

\starttikzpicture
\node[fill=mycola,rectangle, minimum height=4cm,minimum width=2cm] {\startcolor[mycola]T\stopcolor};
\node[fill=mycolb,rectangle, minimum height=4cm,minimum width=2cm] at (2,0) {\startcolor[mycolb]T\stopcolor};
\node[fill=mycolc,rectangle, minimum height=4cm,minimum width=2cm] at (4,0) {\startcolor[mycolc]T\stopcolor};
\stoptikzpicture

\startMPcode
 fill fullsquare xscaled 2cm yscaled 4cm withcolor \MPcolor{mycola};
 fill fullsquare xscaled 2cm yscaled 4cm xshifted 2cm withcolor \MPcolor{mycolb};
 fill fullsquare xscaled 2cm yscaled 4cm xshifted 4cm withcolor \MPcolor{mycolc};
\stopMPcode

\par
\startcolor[mycola]T\stopcolor
\startcolor[mycolb]T\stopcolor
\startcolor[mycolc]T\stopcolor
\stoptext


2015-04-17 1:27 GMT+02:00 Hans Hagen <pragma@wxs.nl>:
On 4/16/2015 11:29 PM, Christian Prim wrote:
Hi Hans

sorry to ask again. But the different color handling between
context-version before 2015.04.14 00:54 and
context-version 2015.04.14 00:54 is remarkable and annoying.

See attached pdf-documents. Both have exactly the same source:

\usemodule[tikz]
\setupbodyfont[40pt]
\starttext
\definecolor[mycola][c=0.23,m=0.58,y=0.88,k=0.45]
\definecolor[mycolb][c=0.115,m=0.29,y=0.44,k=0.225]
\definecolor[mycolc][c=0.055,m=0.145,y=0.22,k=0.1125]

\starttikzpicture
\node[fill=mycola,rectangle, minimum height=4cm,minimum
width=2cm,anchor=south west] {\startcolor[mycola]T\stopcolor};
\node[fill=mycolb,rectangle, minimum height=4cm,minimum
width=2cm,anchor=south west] at (2,0) {\startcolor[mycolb]T\stopcolor};
\node[fill=mycolc,rectangle, minimum height=4cm,minimum
width=2cm,anchor=south west] at (4,0) {\startcolor[mycolc]T\stopcolor};
\stoptikzpicture
\stoptext

I write in each box the letter T with exactly the same color as the
underlying box. Textcolor is set using context, fill color of the box is
set using tikz.

old.pdf shows the correct color handling. The letter T has exactly the
same color as the box and therefore disappears.

With newest beta (new.pdf) the letter T is visible.

Must I now stay with an old beta or can this "bug" be fixed? Perhaps
it's a bug in tikz...

i found out that it relates to the lack of gray support (which in fact seems to be rgb support)

so the next beta might work ok for you (no upload yet)

Hans



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