This is the version I ended up with, seems to do exactly what I had in mind:
\startuniqueMPgraphic{mpshadow}
% BodyFontSize should be the current font size of/in the frame
mw := BodyFontSize/3;
ox := 3 ; % offset x
oy := 2 ; % offset y
bx := 1.7mw ; % bleed x (height of the shadow)
by := 3mw ; % bleed y (width of the shadow)
rx := 2mw ; % max. corner radius x
ry := 1mw ; % max. corner radius y
steps := 10 ; % number of shadow layers, 10 is a good value
hue := 0.03 ; % 0.02 is a good value
ycorr := 1mw ; % difference between overlay height and shadow height
for step = 1 upto steps:
part := (step-1)/steps;
xstep := bx * part ; % current part of bleed
ystep := by * part ;
crx := (rx + rx*part)/2; % current radius
cry := (ry + ry*part)/2;
% points of the rounded rectangle
xa := -xstep + ox;
xb := -xstep + ox + crx;
xc := xstep + ox - crx + \overlaywidth;
xd := xstep + ox + \overlaywidth;
ya := -ystep + ycorr + oy;
yb := -ystep + ycorr + oy + cry;
yc := ystep - ycorr + oy - cry + \overlayheight;
yd := ystep - ycorr + oy + \overlayheight;
fill (xb, ya)---
(xc, ya)...
(xd, yb)---
(xd, yc)...
(xc, yd)---
(xb, yd)...
(xa, yc)---
(xa, yb)...cycle
withcolor transparent(1, hue, black) ;
endfor;
setbounds currentpicture to OverlayBox ;
\stopuniqueMPgraphic
\defineoverlay[shadow][\useMPgraphic{mpshadow}]
\setupexternalfigures[location=default]
\starttext
\startplacefigure
[title={MyTitle.}]
\externalfigure[mill]
\stopplacefigure
\blank[2em]
\startplacefigure
[title={MyTitle.}]
\externalfigure[mill][background=shadow]
\stopplacefigure
\stoptext
Op zo 11 mei 2025 om 15:18 schreef Wolfgang Schuster <
wolfgang.schuster.li...@gmail.com>:
> Am 10.05.2025 um 21:39 schrieb Jeroen:
> > Is there a way with metapost to get a slightly off-centered (upper-
> > right) shadow around a figure?
>
> This a simple version (the \setupexternalfigures line is needed to load
> the example image because it won't wotk with dummy graphics):
>
> \startuseMPgraphic{shadow}
> fill OverlayBox shifted (EmWidth/2,EmWidth/2) withcolor "lightgray" ;
> setbounds currentpicture to OverlayBox ;
> \stopuseMPgraphic
>
> \defineoverlay [shadow] [\useMPgraphic{shadow}]
>
> \setupexternalfigures[location=default]
>
> \starttext
>
> \externalfigure[mill]
> \blank
> \externalfigure[mill][background=shadow]
>
> \stoptext
>
> Wolfgang
>
>
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>
> ___________________________________________________________________________________
>
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl /
https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive : https://github.com/contextgarden/context
wiki : https://wiki.contextgarden.net
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