Re: Transparency (Metapost)

[Hans Hagen <j.hagen@xs4all.nl>]

On 12/1/2019 11:32 AM, Fabrice Couvreur wrote:
> Hello
> Thank you for your suggestion. However, it works with context and not 
> with lmtx.
> Fabrice
> 
> \starttext
> \startMPcode
>     defaultfont := "texgyrepagella-regular*default" ;
>     defaultscale :=0.8;
> 
>     color brown;
>     brown = (0.128,0.00,0.00);
> 
>     path twos, threes, sixes;
>     twos = fullcircle xscaled 4cm yscaled 2cm rotated 180
>            shifted 42 left;
>     threes = fullcircle xscaled 4cm yscaled 2cm shifted 42 right;
>     sixes = buildcycle(twos, threes);
> 
>     fill twos   withcolor brown withtransparency(1,0.75);
>     fill threes withcolor yellow withtransparency(1,0.75);
>     fill sixes withcolor yellow + brown withtransparency(1,0.75);
> 
>     draw twos;
>     draw threes;
> 
>     label("...",(1.5cm,0));
>     label("...",(0,0));
>     label("...",(-1.5cm,0));
>     label.top("yeux marron",(-1.5cm,1.25cm));
>     label.top("cheveux blonds",(1.5cm,1.25cm));
> \stopMPcode
> \stoptext
> 
> tex error       > tex error on line 1 in file ./blond.tex: ?
Looks ok here ... but isn't the transparacy used instead of the sizes? 
Anyway, you can use named colors

\starttext

\startMPcode
    defaultfont  := "texgyrepagella-regular*default" ;
    defaultscale := 0.8 ;

    definecolor [ name = "mp:red",   b = 1 ] ;
    definecolor [ name = "mp:green", y = 1 ] ;

    path twos, threes ;
    twos   := fullcircle xscaled 4cm yscaled 2cm rotated 180 shifted 42 
left ;
    threes := fullcircle xscaled 4cm yscaled 2cm             shifted 42 
right ;

    fill twos   withcolor "mp:red"   withtransparency(1,0.5) ;
    fill threes withcolor "mp:green" withtransparency(1,0.5) ;

    draw twos ;
    draw threes ;

    label("...",( 1.5cm,0));
    label("...",( 0,    0));
    label("...",(-1.5cm,0));
    label.top("\strut yeux marron",   (-1.5cm,1.25cm));
    label.top("\strut cheveux blonds",( 1.5cm,1.25cm));
\stopMPcode

\stoptext

(you cannot overload colors at the tex level in mp but use them in order 
to be consistent)

Hans

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                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
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