On Thu, 20 May 2021, Jeroen wrote:
> I have the following working example with hatching. This works fine, but
> when I uncomment the sketching commands, no figure is rendered. Is the
> mp-sketch macro still working?
Seems to be working here with LMTX ver. 2021.04.29. See attached.
Aditya
hatch.pdf
Description: Adobe PDF document
hatch.tex
Description: TeX document
%D \module
%D [ file=mp-sketch.mp
%Dversion=2021.05.13
%D title=\CONTEXT\ \METAPOST\ graphics,
%D subtitle=Sketch drawing,
%D author=Aditya Mahajan,
%D date=\currentdate,
%D copyright={Aditya Mahajan}]
%D This metapost module is inspired by a TeX.SE question:
%D http://tex.stackexchange.com/q/39296/323
%D
%D I thought that it would be fun to implement a similar feature in MetaPost.
%D
%D To use this package in MetaPost:
%D
%D \starttyping
%Dinput mp-sketch;
%D
%Dbeginfig(1)
%D sketchypaths; % Make draw and fill sketchy
%D ...
%D naturalizepaths; % Restore the value of draw and fill
%D ...
%Dendfig
%D \stoptyping
%D
%D The code is heavily inspired by Hans Hagen's Metafun macros.
%D
%D The macro \type{sketchypaths} is modeled after \type{visualizepaths} from
%D \filename{mp-tool}.
def sketchypaths =
let draw = sketchdraw ;
let fill = sketchfill ;
enddef ;
%D Check if \filename{mp-tool} is loaded
if not known context_tool :
let normaldraw = draw;
let normalfill = fill;
def naturalizepaths =
let fill = normalfill ;
let draw = normaldraw ;
enddef ;
fi
%D The variable \type{sketch_amount} determines the amount of randomness in the
%D drawing
numeric sketch_amount; sketch_amount := 0.75bp;
%D The variable \type{sketch_passes} determines the number of times the path
%D is drawn
numeric sketch_passes; sketch_passes := 1;
%D Based on \type{randomized}. Assumes p is path:
numeric sketch_segments; sketch_segments := 20;
primarydef p sketchrandomized s = (
if path p :
for t = 0 step 1/sketch_segments until 1-1/sketch_segments :
((point (t*arclength(p)) on p)
randomshifted s) .. controls
((postcontrol (t*arclength(p)) on p)
randomshifted s) and
((precontrol ((t+1/sketch_segments)*arclength(p)) on p)
randomshifted s) ..
endfor
if cycle p :
cycle
else :
((point arclength(p) on p) randomshifted s)
fi
else :
p
fi
) enddef ;
%D The macro \type{sketchdraw} draws the randomized path. The
%D \type{expr} ... \type{text} trick is copied from the definition of
%D \type{drawarrow}
def sketchdraw expr p =
do_sketchdraw(p)
enddef;
def do_sketchdraw(expr p) text t =
if (path p) :
for i = 1 upto max(1,sketch_passes) :
normaldraw p
sketchrandomized sketch_amount
withtransparency ("multiply", 1/max(1,sketch_passes))
t ;
endfor;
else :
normaldraw p t;
fi
enddef;
%D The macro \type{sketchfill} randomizes the path before filling it.
def sketchfill expr p =
do_sketchfill(p)
enddef ;
def do_sketchfill(expr p) text t =
if (path p) :
for i = 1 upto max(1,sketch_passes) :
normalfill p
randomized sketch_amount
withtransparency ("multiply", 1/max(1,sketch_passes))
t ;
endfor;
else :
normalfill p t;
fi
enddef;
endinput;
% Modified example from
% http://tex.loria.fr/prod-graph/zoonekynd/metapost/metapost.html
beginfig(1)
pair A,B,C,O;
A=(0,0); B=(3cm,0); C=(1cm,2cm);
O - 1/2[B,C] = whatever * (B-C) rotated 90;
O - 1/2[A,B] = whatever * (A-B) rotated 90;
sketchypaths;
sketch_amount := 5bp;
draw A--B--C--cycle;
draw O withpen pencircle scaled 4bp;
sketch_amount := 2bp;
draw fullcircle scaled 2abs(O-A) shifted O;
endfig
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