Re: [NTG-context] Metafun textext()

11 Jan 2013

      On 1/10/2013 2:18 PM, Aditya Mahajan wrote:
...
On Thu, 10 Jan 2013, Alan BRASLAU wrote:
...
On Thu, 10 Jan 2013 06:51:50 -0500
Aditya Mahajan  wrote:
...
Since the beginning of MkIV, colors in metapost labels need to be set at
the ConTeXt end (Untested):
T := thelabel(textext("\color[blue]{I'm seeing double}"), origin);
Aditya
I don't believe that this is true, but I am most likely wrong.
Well, I think it was true in the beginning (as I remember a discussion
from Mojca on how to handle labels differently in the gnuplot module),
but clearly that is not the case now.
...
Indeed "\blue text" has worked, but 'draw T withcolor blue;' *should*
work as well.
The processing of textext() has changed recently, it seems.
The mkiv implementation has always been rather different from the mkii 
one: text handling as well as dealing with colors.
...
...
\startMPcode
label(textext("I'm seeing double"),origin)     withcolor green ;
label(textext("I'm seeing double"),(-1mm,1mm)) withcolor blue ;
\stopMPcode
DOES work.
Of course, these are much simplified minimal examples of what I would
like to do.
Minimal example to show what is happening:
\startbuffer[initialize]
   picture T;
   T := textext("Hello");
picture Q;
   Q := T;
\stopbuffer
\startbuffer[T]
   draw T withcolor blue;
\stopbuffer
\startbuffer[Q]
   draw Q shifted (-1mm, 1mm) withcolor red;
\stopbuffer
\startlines
Only draw T: \processMPbuffer[initialize,T]
Only draw Q: \processMPbuffer[initialize,Q]
Draw T & Q : \processMPbuffer[initialize,T,Q]
Draw Q & T : \processMPbuffer[initialize,Q,T]
\stoplines
You and Alan can pick up the beta from the ftp server and play with this:

\setupbodyfont[dejavu]

\starttext

\startMPpage[offset=10pt]

     picture MyText ; MyText := textext("Dummy") ; % not used later on

     picture MyText ; MyText := textext("\red Red") ;

     draw MyText ;

     draw MyText scaled 2 shifted (0,-1cm) ;

     draw MyText scaled 3 shifted (0,-2cm) ;

     picture MyText ; MyText := textext("Blue Green Red") ;

     draw MyText rotatedaround(center MyText,10) shifted (0,-3cm) 
withcolor blue ;

     draw MyText shifted (0,-4cm) withcolor green ;

     draw MyText rotatedaround(center MyText,-10) shifted (0,-5cm) 
withcolor red ;

     picture MyText ; MyText := image (
         draw textext("Green Red Blue {\yellow YELLOW} Whatever 1") ;
         draw textext("Green Red Blue {\yellow YELLOW} Whatever 2") 
shifted (10cm,0) ;
     ) ;

     draw MyText shifted (0,-6cm) withcolor green ;

     draw MyText shifted (0,-7cm) withcolor red ;

     draw MyText shifted (0,-8cm) withcolor blue ;

\stopMPpage

\stoptext

The complication is that we reuse a picture which once defined has 
frozen properties. However, after hours of lua/tex juggling I managed to 
made a variant that better keeps track of applied colors. I'm not sure 
if this is foolproof but it's probably quite ok for what Alan wants to 
do. Although ... being a scientist he will look for the next frontier 
... (or even more scientific: try to prove me wrong).

Hans
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