Cover page coloring in ConTeXt

Question

How would I go about coloring the top and bottom of a page in ConTeXt/Metafun?

Currently I am using this code

\definecolor [Top] [h=00ff00]
\definecolor [Bottom] [h=ff0000]
\definecolor [TitleColor] [h=0000ff]
\setupmakeup [CoverPage] [pagestart=yes]
\definehighlight [CoverTitle] [color=TitleColor]

\startuseMPgraphic{Head}
    StartPage ;
         fill Page withcolor \MPcolor{Top} ;
    StopPage ;
\stopuseMPgraphic

\defineoverlay[page][\useMPgraphic{Head}]
\setupbackgrounds[page][background=page]

\starttext
\startmakeup[CoverPage][doublesided=no]
    \definedfont[Serif at 20.7pt]\setstrut \strut Author \par
    \definedfont[Serif at 32.7pt]\setstrut \strut \TitleColor{Cover Page Title} \par
    % I would like to separate the top and bottom colors here.
    \definedfont[Serif at 24.9pt]\setstrut \strut \TitleColor{Subhead Title}
\stopmakeup
\stoptext

Which obviously returns a page with a single color.

I am learning ConTeXt/Metafun, so the above code is "cargo cult"-ish. If there is a better way I would like to know.

Answer 1

For such specific placement requirements it's probably the easiest to just design the whole page in MetaFun. I have also adapted it to look more more “Motion Mountainy”. The picture shows the mountain Matterhorn, the highest peak in Switzerland. It's royalty free and obtained from here: https://pixabay.com/en/matterhorn-snow-mountain-panorama-3051346/

\setupbodyfont [minion]

\definecolor [Top] [h=a5b291]
\definecolor [Bottom] [h=b7c1a7]
\definecolor [TitleColor] [h=96433a]

\define[1]\titlefont{%
  \setcharacterkerning[extrakerning]%
  \cap
  \definedfont[#1]%
  \ignorespaces
}

\starttext

\startMPpage

    StartPage ;

    numeric w ; w := bbwidth(Page) ;
    numeric h ; h := bbheight(Page) ;

    fill (unitsquare xyscaled (w,.8h)) withcolor \MPcolor{Bottom} ;
    fill (unitsquare xyscaled (w,.2h) yshifted .8h) withcolor \MPcolor{Top} ;
    draw (0,.8h) -- (w,.8h) withpen pensquare scaled 2pt withcolor white ;

    draw textext.rt("\definedfont[Serif at 20.7pt]Author") shifted (.1w,.95h) ;
    draw textext.rt("\titlefont{Serif at 45.2pt} Cover Page Title") shifted (.1w,.85h) withcolor \MPcolor{TitleColor} ;
    draw textext.rt("\titlefont{SerifBold at 20.7pt} Subhead Title") shifted (.1w,.75h) withcolor \MPcolor{TitleColor} ;
    draw textext.rt("\titlefont{SerifBold at 20.7pt} Another subhead") shifted (.1w,.70h) ;

    picture p; p := externalfigure "matterhorn.png" ;
    draw p scaled (w/bbwidth p) ;

    StopPage ;

\stopMPpage

\stoptext