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* John Hobby's page: http://cm.bell-labs.com/who/hobby/MetaPost.html* Current development: https://foundry.supelec.fr/projects/metapost/ MetaPost is a graphical programming language, based on Donald Knuth's MetaFont. Normally MP graphics are converted to PostScript and used with dvips, but ConTeXt can use it directly with PDF (see the[http://www.pragma-ade.com/general/sources/mptopdf.pdf MPtoPDFMP to PDF]manual). MetaPost is ConTeXt's "native" graphics mode, see [[MetaFun]].
Added Hans, the provider of the solution to the problem with textext...
< [[Math]], [[MetaFun]], [[Graphics]]
MetaPost is ConTeXt's native graphics language. [[MetaFun]] is a MetaPost module by Hans Hagen that adds a lot of extra features; it is enabled by default, so one could say that MetaFun is ConTeXt's default dialect of MetaPost.
== Documentation & Tutorials ==
* [http://www.ctantug.org/tex-archive/graphicsdocs/metapost/mpman.pdf A User's Manual for MetaPost] <!-- http://cm.bell-labs.com/who/hobby/cstr_162.pdf has its pages reversed -->
* [http://remote.science.uva.nl/~heck/Courses/mptut.pdf Learning METAPOST by doing] ([http://maps.aanhet.net/maps/pdf/32_14.pdf this] and [http://maps.aanhet.net/maps/pdf/32_15.pdf this link] are not working)
* [http://www.tug.org/pracjourn/2006-4/henderson/henderson.pdf A Beginner's Guide to METAPOST for Creating High-Quality Graphics] by Troy Henderson
* [[manual:metafun-s.pdf|MetaFun]]
* [http://tex.loria.fr/prod-graph/zoonekynd/metapost/metapost.html Lots of examples]
* [[Color in MetaPost]] describes how to get color mixtures, TeX colors, and transparent effects in MetaPost graphics.
* [http://wiki.contextgarden.net/MetaPost_in_ConTeXt MetaPost in ConTeXt]
== Using MetaPost in ConTeXt ==
With {{cmd|startuseMPgraphic}}, you define a piece of graphics code that is processed anew every time the graphic is placed with {{cmd|useMPgraphic}}. Further commands are described at [[MetaPost in ConTeXt]].
<context source=yes>
\def\mycolor{.625red}
\startuseMPgraphic{name}
fill fullcircle scaled 20pt withcolor \mycolor;
\stopuseMPgraphic
red: \useMPgraphic{name}
\def\mycolor{.625blue}
blue: \useMPgraphic{name}
</context>
== Different Packages, Extensions & Applications of Metapost ==
* [http://www.ctan.org/tex-archive/graphics/metaplot/ MetaPlot] - graph drawing
* [http://www.ctan.org/tex-archive/graphics/metapost/contrib/macros/metaobj/ MetaObj] - object-oriented drawing, see also the page about [[MetaObj and Labels]]
* [http://stud4.tuwien.ac.at/~e0225855/finomaton/finomaton.html finomaton] - drawing finite state automata
* [http://www-math.univ-poitiers.fr/~phan/statsmac.html statsmac] - metapost macros for statistics graphs
* [http://metauml.sourceforge.net/ MetaUML] - MetaPost library for typesetting UML diagrams
* [http://vigna.dsi.unimi.it/metagraph/ METAGRAPH] - drawing (un)directed graphs
=== 3D support ===
* [http://asymptote.sourceforge.net/ Asymptote] - inspired by MetaPost & fully generalizes MetaPost path construction algorithms to three-dimensions
== Testing plain MetaPost ==
To test whether MetaPost is installed on your system, create a file called {{code|test.mp}}:
beginfig(1)
draw fullcircle scaled 3cm ;
endfig ;
end ;
* apply MetaPost on the testfile
mp test.mp
or
mpost test.mp
* that should create a postscript file test.1
* open test.1 with a postscript viewer like Ghostview, Okular, … You should see a circle.
== Testing MetaPost embedded in ConTeXt ==
If MetaPost is installed on your system and working correctly, you can
\starttext
\startMPcode
draw fullcircle scaled 3cm;
\stopMPcode
\stoptext
* for mkii you need to have write18 support enabled and run
texexec --pdf test.tex
* for mkiv run
context test.tex
* that should create a pdf file test.pdf
* open test.pdf with a pdf viewer like Adobe Acrobat, Okular... You should see a circle.
== Text in MetaPost ==
Text that is typeset using `textext` or `btex … etex` adapts to the body font. However, when `label("Foo", pair)` or `"Foo" infont defaultfont` is used, which is not the recommended way, the text is typeset using the font `MetafunDefault`, which can be changed if desired. Example:
<context mode="mkiv" source="yes" text="Gives:">
\starttext
\startMPcode
label("Foo", origin);
draw textext("Bar") yshifted -LineHeight;
\stopMPcode
\definefontsynonym
[MetafunDefault]
[Bold*default]
\switchtobodyfont [pagella, 18pt]
\startMPcode
label("Foo", origin);
draw textext("Foo") yshifted -LineHeight;
\stopMPcode
\stoptext
</context>
The recommended way to typeset text is to use the `textext` macro and change the font using {{cmd |setupMPinstance}}.
== Repetition of a Text Element to Fill a Bar Using textext ==
Imagine you want to create a frame which consists out of one glyph or a combination of different glyphs in order to make a decorative border. For this purpose a series of such elements should be placed on the bar as pictures, evenly spaced. Probably you want to have at the end of the bar a different glyph inserted as a picture too.
The following code is working but the last picture is not the expected glyph. One would expect 14 times the "?" and at the end of the bar a "*":
<context mode="mkiv" source="yes" text="Gives:">
\starttext
\startMPpage
picture PicA ; PicA := textext("*");
picture PicB ; PicB := textext("?");
numeric Step ; Step := 2cm div bbwidth(PicB) ;
for i = 1 upto Step :
draw PicB shifted (i*5mm,0) ;
endfor ;
draw PicA ;
\stopMPpage
\stoptext
</context>
What you get is 15 "?" but no "*"!
In order to get this corrected one needs to calculate the boundingbox of the "?" on beforehand. Hans Hagen provided this solution on 14-10-2014.
<context mode="mkiv" source="yes" text="Gives:">
\starttext
\startMPcalculation
path PicX ; PicX := boundingbox textext("?") ;
\stopMPcalculation
\startMPpage
picture PicA ; PicA := textext("*");
picture PicB ; PicB := textext("?");
numeric Step ; Step := 2cm div bbwidth(PicX) ;
% numeric Step ; Step := 2cm div bbwidth(PicB) ;
for i = 1 upto Step :
draw PicB shifted (i*5mm,0) ;
endfor ;
draw PicA ;
\stopMPpage
\stoptext
</context>
Now you get 14 "?" and the "*".
=== A Full Example ===
<context mode="mkiv" source="yes" text="Gives:">
\setupbodyfont[8pt]
\defineoverlay[Myframe][\reuseMPgraphic{Frame}]
\setuppapersize[A8][A8]
\setuplayout
[topspace=5mm,
backspace=5mm,
height=middle,
width=middle,
header=0pt,
footer=0pt]
\starttext
% ======== Definition of the frame in Metafun ==========
\startMPcalculation
path PicX ; PicX := boundingbox textext("= : =") ;
\stopMPcalculation
\startreusableMPgraphic{Frame}
numeric u,v,xshift,yshift,picwidth,remnant,nelements;
u := OverlayWidth;
v := OverlayHeight;
path p,w;
p := unitsquare xscaled u yscaled v;
w := fullcircle scaled 8pt;
picture Edgepic,Linepic[];
color edgedotcolor,linelementcolorA;
edgedotcolor := blue;
linelementcolorA := red;
Linepic[1] := textext("\rotate[rotation=90]{= : =}");
Linepic[2] := textext("= : =");
Edgepic := textext("o");
%Calculations for the horizontal frame-element placement:
% In order to make this work, the width of the line element needs to be calculated on beforehand.
% path PicX; PicX := textext(")(");
picwidth := bbwidth(PicX);
nelements := u div picwidth;
remnant := u mod picwidth;
xshift := picwidth + remnant/nelements;
Linepic[3] := Linepic[2] shifted (0.5*picwidth,0);
for a = llcorner p, ulcorner p :
for i = 1 upto nelements :
draw Linepic[3] shifted ((xpart a + (i-1)*xshift),ypart a) withcolor linelementcolorA;
endfor;
endfor;
%Calculations for the vertical frame-element placement:
picheight := bbwidth(PicX);
nelements := v div picheight;
remnant := v mod picheight;
yshift := picheight + remnant/nelements;
Linepic[4]:= Linepic[1] shifted (0,0.5*picheight);
for a = llcorner p, lrcorner p :
for i = 1 upto nelements:
draw Linepic[4] shifted (xpart a,ypart a + (i-1)*yshift) withcolor linelementcolorA;
endfor;
endfor;
for i = llcorner p, lrcorner p,ulcorner p,urcorner p :
fill w shifted (xpart i,ypart i) withcolor white;
draw Edgepic shifted (xpart i,ypart i) withcolor edgedotcolor;
endfor;
% For frame-element positioning checking:
% draw p;
%
\stopreusableMPgraphic
% ==========
\startframedtext
[width=0.8\textwidth,height=0.8\textheight,frame=off,background=Myframe, align={middle,lohi}]
The butterfly counts not months but moments, and has time enough.
\blank
{\tfx Rabindranath Tagore}
\stopframedtext
\stoptext
</context>
There is some strange cropping going on on the Wiki-implementation. Of course the left frame is in reality equal to the right frame...
There is one important remark: The MPcalculation and the drawing itself must be inside \starttext ... \stoptext.
== Other Links ==
* Metapost home page: http://tug.org/metapost
* John Hobby's page: http://cm.bell-labs.com/who/hobby/MetaPost.html
* Current development: http://foundry.supelec.fr/projects/metapost/
* http://melusine.eu.org/syracuse/metapost/
[[Category:Graphics]]
[[Category:Metapost]]
