% Reference Card for Asymptote

% Copyright (c) 2011 John C. Bowman. May be freely distributed.
% Thanks to Stephen Gildea for the multicolumn macro package
% and Joseph H. Silverman for the C Reference card.

%**start of header
\newcount\columnsperpage

\overfullrule=0pt

% This file can be printed with 1, 2, or 3 columns per page (see below).
% [For 2 or 3 columns, you'll need 6 and 8 point fonts.]
% Specify how many you want here.  Nothing else needs to be changed.

\columnsperpage=2

% This reference card is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

% This file is intended to be processed by plain TeX (TeX82).
%
% The final reference card has six columns, three on each side.
% This file can be used to produce it in any of three ways:
% 1 column per page
%    produces six separate pages, each of which needs to be reduced to 80%.
%    This gives the best resolution.
% 2 columns per page
%    produces three already-reduced pages.
%    You will still need to cut and paste.
% 3 columns per page
%    produces two pages which must be printed sideways to make a
%    ready-to-use 8.5 x 11 inch reference card.
%    For this you need a dvi device driver that can print sideways.
% Which mode to use is controlled by setting \columnsperpage above.
%
%  (reference card macros due to Stephen Gildea)
%

\def\versionnumber{0.0}  % Version of this reference card
\def\year{2011}
\def\month{August}
\def\version{\month\ \year\ v\versionnumber}

\def\shortcopyrightnotice{\vskip .5ex plus 2 fill
  \centerline{\small \copyright\ \year\ John C. Bowman
  Permissions on back.  v\versionnumber}}

\def\copyrightnotice{
\vskip 1ex plus 100 fill\begingroup\small
\centerline{\version. Copyright \copyright\ \year\ John C. Bowman}

Permission is granted to make and distribute copies of
this card provided the copyright notice and this permission notice
are preserved on all copies.
\endgroup}

% make \bye not \outer so that the \def\bye in the \else clause below
% can be scanned without complaint.
\def\bye{\par\vfill\supereject\end}

\newdimen\intercolumnskip
\newbox\columna
\newbox\columnb

\def\ncolumns{\the\columnsperpage}

\message{[\ncolumns\space 
  column\if 1\ncolumns\else s\fi\space per page]}

\def\scaledmag#1{ scaled \magstep #1}

% This multi-way format was designed by Stephen Gildea
% October 1986.
\if 1\ncolumns
  \hsize 4in
  \vsize 10in
  \voffset -.7in
  \font\titlefont=\fontname\tenbf \scaledmag3
  \font\headingfont=\fontname\tenbf \scaledmag2
		\font\headingfonttt=\fontname\tentt \scaledmag2
  \font\smallfont=\fontname\sevenrm
  \font\smallsy=\fontname\sevensy

  \footline{\hss\folio}
  \def\makefootline{\baselineskip10pt\hsize6.5in\line{\the\footline}}
\else
  \hsize 3.2in
  \vsize 7.95in
  \hoffset -.75in
  \voffset -.745in
  \font\titlefont=cmbx10 \scaledmag2
  \font\headingfont=cmbx10 \scaledmag1
		\font\headingfonttt=cmtt10 \scaledmag1
  \font\smallfont=cmr6
  \font\smallsy=cmsy6
  \font\eightrm=cmr8
  \font\eightbf=cmbx8
  \font\eightit=cmti8
  \font\eighttt=cmtt8
  \font\eightsy=cmsy8
  \font\eightsl=cmsl8
  \font\eighti=cmmi8
  \font\eightex=cmex10 at 8pt
  \textfont0=\eightrm  
  \textfont1=\eighti
  \textfont2=\eightsy
  \textfont3=\eightex
  \def\rm{\fam0 \eightrm}
  \def\bf{\eightbf}
  \def\it{\eightit}
  \def\tt{\eighttt}
  \def\sl{\eightsl}
  \normalbaselineskip=.8\normalbaselineskip
  \normallineskip=.8\normallineskip
  \normallineskiplimit=.8\normallineskiplimit
  \normalbaselines\rm		%make definitions take effect

  \if 2\ncolumns
    \let\maxcolumn=b
    \footline{\hss\rm\folio\hss}
    \def\makefootline{\vskip 2in \hsize=6.86in\line{\the\footline}}
  \else \if 3\ncolumns
    \let\maxcolumn=c
    \nopagenumbers
  \else
    \errhelp{You must set \columnsperpage equal to 1, 2, or 3.}
    \errmessage{Illegal number of columns per page}
  \fi\fi

  \intercolumnskip=.46in
  \def\abc{a}
  \output={%
      % This next line is useful when designing the layout.
      %\immediate\write16{Column \folio\abc\space starts with \firstmark}
      \if \maxcolumn\abc \multicolumnformat \global\def\abc{a}
      \else\if a\abc
	\global\setbox\columna\columnbox \global\def\abc{b}
        %% in case we never use \columnb (two-column mode)
        \global\setbox\columnb\hbox to -\intercolumnskip{}
      \else
	\global\setbox\columnb\columnbox \global\def\abc{c}\fi\fi}
  \def\multicolumnformat{\shipout\vbox{\makeheadline
      \hbox{\box\columna\hskip\intercolumnskip
        \box\columnb\hskip\intercolumnskip\columnbox}
      \makefootline}\advancepageno}
  \def\columnbox{\leftline{\pagebody}}

  \def\bye{\par\vfill\supereject
    \if a\abc \else\null\vfill\eject\fi
    \if a\abc \else\null\vfill\eject\fi
    \end}  
\fi

% we won't be using math mode much, so redefine some of the characters
% we might want to talk about
\catcode`\^=12
%\catcode`\_=12
\catcode`\~=12

\chardef\\=`\\
\chardef\{=`\{
\chardef\}=`\}
\chardef\underscore=`\_

\hyphenation{}

\parindent 0pt
\parskip .85ex plus .35ex minus .5ex

\def\small{\smallfont\textfont2=\smallsy\baselineskip=.8\baselineskip}

\outer\def\newcolumn{\vfill\eject}

\outer\def\title#1{{\titlefont\centerline{#1}}\vskip 1ex plus .5ex}

\outer\def\section#1{\par\filbreak
  \vskip .5ex  minus .1ex {\headingfont #1}\mark{#1}%
  \vskip .3ex  minus .1ex}

\outer\def\librarysection#1#2{\par\filbreak
  \vskip .5ex  minus .1ex {\headingfont #1}\quad{\headingfonttt<#2>}\mark{#1}%
  \vskip .3ex  minus .1ex}


\newdimen\keyindent

\def\beginindentedkeys{\keyindent=1em}
\def\endindentedkeys{\keyindent=0em}
\def\begindoubleindentedkeys{\keyindent=2em}
\def\enddoubleindentedkeys{\keyindent=1em}
\endindentedkeys

\def\paralign{\vskip\parskip\halign}

\def\<#1>{$\langle${\rm #1}$\rangle$}

\def\kbd#1{{\tt#1}\null}	%\null so not an abbrev even if period follows

\def\beginexample{\par\vskip1\jot
\hrule width.5\hsize
\vskip1\jot
\begingroup\parindent=2em
  \obeylines\obeyspaces\parskip0pt\tt}
{\obeyspaces\global\let =\ }
\def\endexample{\endgroup}

\def\Example{\qquad{\sl Example\/}.\enspace\ignorespaces}

\def\key#1#2{\leavevmode\hbox to \hsize{\vtop
  {\hsize=.75\hsize\rightskip=1em
  \hskip\keyindent\relax#1}\kbd{#2}\hfil}}

\newbox\metaxbox
\setbox\metaxbox\hbox{\kbd{M-x }}
\newdimen\metaxwidth
\metaxwidth=\wd\metaxbox

\def\metax#1#2{\leavevmode\hbox to \hsize{\hbox to .75\hsize
  {\hskip\keyindent\relax#1\hfil}%
  \hskip -\metaxwidth minus 1fil
  \kbd{#2}\hfil}}

\def\threecol#1#2#3{\hskip\keyindent\relax#1\hfil&\kbd{#2}\quad
  &\kbd{#3}\quad\cr}

% Define Italic Names
\def\makedef#1 {%
\expandafter\edef\csname#1\endcsname{\hbox{\it#1\/}}}
\makedef array
\makedef arg
\makedef const
\makedef dim
\makedef expr
\makedef filename
\makedef fnc
\makedef format
\makedef member
\makedef name
\makedef statement
\makedef statements
\makedef string
\makedef type
\makedef value
\makedef var

%**end of header


\title{Asymptote Reference Card}

\section{Program structure/functions}
\halign{\tt#\hfil&\qquad#\hfil\cr
import "\filename"&import module\cr
import "\filename" as name&import filename as module name\cr
include "\filename"&include verbatim text from file\cr
\type\ \fnc(\type,\dots);&optional function declaration\cr
\type\ \name;&variable declaration\cr
\type\ \fnc(\type\ \arg,\dots) \{&function definition\cr
\quad\statements\cr
\quad return \value;\cr
\}\cr
}

\section{Data types/declarations}
\key{boolean (true or false)}{bool}
\key{tri-state boolean (true, default, or false)}{bool3}
\key{integer}{int}
\key{float (double precision)}{real}
\key{ordered pair (complex number)}{pair}
\key{character string}{string}
\key{fixed piecewise cubic Bezier spline}{path}
\key{unresolved piecewise cubic Bezier spline}{guide}
\key{color, line type/width/cap, font, fill rule}{pen}
\key{label with position, alignment, pen attributes}{Label}
\key{drawing canvas}{picture}
\key{affine transform}{transform}
\key{constant (unchanging) value}{const}
\key{allocate in higher scope}{static}
\key{no value}{void}
\key{inhibit implicit argument casting}{explicit}
\key{structure}{struct}
\key{create name by data type}{typedef \type\ \name}

\section{3D data types (import three;)}
\key{ordered triple}{triple}
\key{3D path}{path3}
\key{3D guide}{guide3}
\key{3D affine transform}{transform3}

\section{Constants}
\key{exponential form}{6.02e23}
\key{\TeX\ string constant}{"abc\dots de"}
\key{\TeX\ strings: special characters}{\\\\, \\"}
\key{C strings: constant}{'abc\dots de'}
\key{C strings: special characters}{\\\\, \\" \\' \\?}
\key{C strings: newline, cr, tab, backspace}{\\n \\r \\t \\b}
\key{C strings: octal, hexadecimal bytes}{\\0-\\377 \\x0-\\xFF}

\section{Operators}
\key{arithmetic operations}{+ - * /}
\key{modulus (remainder)}{\%}
\key{comparisons}{== != > >= < <=}
\key{not}{!}
\key{and or (conditional evaluation of RHS)}{\&\& ||}
\key{and or xor}{\& | ^}
\key{cast expression to type}{(\type) \expr}
\key{increment decrement prefix operators}{++ --}
\key{assignment operators}{+= -= *= /= \%=}
\key{conditional expression}{\expr$_1$\ {?}\ \expr$_2$\ {:}\ \expr$_3$}
\key{structure member operator}{\name.\member}
\key{expression evaluation separator}{,}

\section{Flow control}
\key{statement terminator}{;}
\key{block delimeters}{\{\quad\}}
\key{comment delimeters}{/*\quad*/}
\key{comment to end of line delimiter}{//}
\key{exit from \kbd{while}/\kbd{do}/\kbd{for}}{break;}
\key{next iteration of \kbd{while}/\kbd{do}/\kbd{for}}{continue;}
\key{return value from function}{return \expr;}
\key{terminate execution}{exit();}
\key{abort execution with error message}{abort(string);}
\metax{{\bf Flow constructions} ({\tt if/while/for/do})\hidewidth}{}
\beginexample
if(\expr)\ \statement
else if(\expr)\ \statement
else \statement
\endexample
\beginexample
while(\expr)
\quad\statement
\endexample
\beginexample
for(\expr$_1$; \expr$_2$; \expr$_3$)
\quad\statement
\endexample
\beginexample
for(\type var : \array)
\quad\statement
\endexample
\beginexample
do \statement
\quad while(\expr);
\endexample

\section{Arrays}
\metax{array}{\type[]\ \name}
\metax{array element i}{\name[i]}
\metax{anonymous array}{new \type[\dim]}
\metax{array containing n deep copies of x}{array(n,x)}
\metax{length}{\name.length}
\metax{cyclic flag}{\name.cyclic}
\metax{pop element {\tt x}}{\name.pop()}
\metax{push element {\tt x}}{\name.push(x)}
\metax{append array {\tt a}}{\name.append(a)}
\metax{insert rest arguments at index {\tt i}}{\name.insert(i,\dots)}
\metax{delete element at index {\tt i}}{\name.delete(i)}
\metax{delete elements with indices in [{\tt i},{\tt j}]}{\name.delete(i,j)}
\metax{delete all elements}{\name.delete()}
\metax{test whether element n is initialized}{\name.initialized(n)}
\metax{array of indices of initialized elements}{\name.keys}
\metax{complement of int array in {\tt \{0,\dots,n-1\}}}{complement(a,n)}
\metax{deep copy of array {\tt a}}{copy(a)}
\metax{array {\tt \{0,1,\dots,n-1\}}}{sequence(n)}
\metax{array {\tt \{n,n+1,\dots,m\}}}{sequence(n,m)}
\metax{array {\tt \{n-1,n-2,\dots,0\}}}{reverse(n)}
\metax{array {\tt \{f(0),f(1),\dots,f(n-1)\}}}{sequence(f,n)}
\metax{array obtained by applying {\tt f} to array {\tt a}}{map(f,a)}
\metax{uniform partition of [{\tt a},{\tt b}] into n intervals}{uniform(a,b,n)}
\metax{concat specified 1D arrays}{concat(a,b,\dots)}
\metax{return sorted array}{sort(a)}
\metax{return array sorted using ordering {\tt less}}{sort(a,{\tt less})}
\metax{search sorted array {\tt a} for key}{search(a,key)}
\metax{index of first true value of bool array {\tt a}}{find(a)}
\metax{index of nth true value of bool array {\tt a}}{find(a,n)}

\section{Initialization}
\key{initialize variable}{\type\ \name=\value;}
\key{initialize array}{\type[]\ \name=\{\dots\};}

\section{path connectors}
\key{straight segment}{--}
\key{Bezi\'er segment with implicit control points}{..}
\key{Bezi\'er segment with explicit control points}{..controls c0 and c1..}
\key{concatenate}{\&}
\key{lift pen}{^^}
\key{..tension atleast 1..}{::}
\key{..tension atleast infinity..}{---}

\section{Labels}
\key{implicit cast of string {\tt s} to Label}{s}
\key{Label {\tt s} with relative position and alignment}{Label(s,real,pair)}
\key{Label {\tt s} with absolute position and alignment}{Label(s,pair,pair)}
\key{Label {\tt s} with specified pen}{Label(s,pen)}

\section{draw commands}
\key{draw path with current pen}{draw(path)}
\key{draw path with pen}{draw(path,pen)}
\key{draw labeled path}{draw(Label,path)}
\key{draw arrow with pen}{draw(path,pen,Arrow)}
\key{draw path on picture}{draw(picture,path)}

\section{fill commands}
\key{fill path with current pen}{fill(path)}
\key{fill path with pen}{fill(path,pen)}
\key{fill path on picture}{fill(picture,path)}

\section{label commands}
\key{label a pair with optional alignment z}{label(Label,pair,{\tt z})}
\key{label a path with optional alignment z}{label(Label,path,{\tt z})}
\key{add label to picture}{label(picture,Label)}

\section{clip commands}
\key{clip to path}{clip(path)}
\key{clip to path with fill rule}{clip(path,pen)}
\key{clip picture to path}{clip(picture,path)}

\section{pens}
\key{Grayscale pen from value in [0,1]}{gray(g)}
\key{RGB pen from values in [0,1]}{rgb(r,g,b)}
\key{CMYK pen from values in [0,1]}{cmyk(r,g,b)}
\key{RGB pen from heximdecimal string]}{rgb(string)}
\key{heximdecimal string from rgb pen]}{hex(pen)}
\key{hsv pen from values in [0,1]}{hsv(h,s,v)}
\key{invisible pen}{invisible}
\key{default pen}{defaultpen}
\key{current pen}{currentpen}
\key{solid pen}{solid}
\key{dotted pen}{dotted}
\key{wide dotted current pen}{Dotted}
\key{wide dotted pen}{Dotted(pen)}
\key{dashed pen}{dashed}
\key{long dashed pen}{longdashed}
\key{dash dotted pen}{dashdotted}
\key{long dash dotted pen}{longdashdotted}
\key{PostScript butt line cap}{squarecap}
\key{PostScript round line cap}{roundcap}
\key{PostScript projecting square line cap}{extendcap}
\key{miter join}{miterjoin}
\key{round join}{roundjoin}
\key{bevel join}{beveljoin}
\key{pen with miter limit}{miterlimit(real)}
\key{zero-winding fill rule}{zerowinding}
\key{even-odd fill rule}{evenodd}
\key{align to character bounding box (default)}{nobasealign}
\key{align to \TeX\ baseline}{basealign}
\key{pen with font size (pt)}{fontsize(real)}
\key{LaTeX pen from encoding,family,series,shape}{font(strings)}
\key{\TeX\ pen}{font(string)}
\key{scaled \TeX\ pen}{font(string,real)}
\key{PostScript font from strings}{Courier(series,shape)}
\key{pen with opacity in [0,1]}{opacity(real)}
\key{construct pen nib from polygonal path}{makepen(path)}
\key{pen mixing operator}{+}

\section{path operations}
\key{number of segments in path {\tt p}}{length(p)}
\key{number of nodes in path {\tt p}}{size(p)}
\key{is path {\tt p} cyclic?}{cyclic(p)}
\key{is segment {\tt i} of path {\tt p} straight?}{straight(p,i)}
\key{is path {\tt p} straight?}{piecewisestraight(p)}
\key{coordinates of path {\tt p} at time {\tt t}}{point(p,t)}
\key{direction of path {\tt p} at time {\tt t}}{dir(p,t)}
\key{direction of path {\tt p} at {\tt length(p)}}{dir(p)}
\key{unit(dir(p)+dir(q))}{dir(p,q)} 
\key{acceleration of path {\tt p} at time {\tt t}}{accel(p,t)}
\key{radius of curvature of path {\tt p} at time {\tt t}}{radius(p,t)}
\key{precontrol point of path {\tt p} at time {\tt t}}{precontrol(p,t)}
\key{postcontrol point of path {\tt p} at time {\tt t}}{postcontrol(p,t)}
\key{arclength of path {\tt p}}{arclength(p)}
\key{time at which {\tt arclength(p)=L}}{arctime(p,L)}
\key{point on path {\tt p} at arclength {\tt L}}{arcpoint(p,L)}
\key{first value {\tt t} at which {\tt dir(p,t)=z}}{dir(p,z)}
\key{time {\tt t} at relative fraction {\tt l} of {\tt arclength(p)}}{reltime(p,l)}
\key{point at relative fraction {\tt l} of {\tt arclength(p)}}{relpoint(p,l)}
\key{point midway along arclength of {\tt p}}{midpoint(p)}
\key{path running backwards along {\tt p}}{reverse(p)}
\key{subpath of {\tt p} between times {\tt a} and {\tt b}}{subpath(p,a,b)}
\key{times for one intersection of paths {\tt p} and {\tt q}}{intersect(p,q)}
\key{times at which {\tt p} reaches minimal extents}{mintimes(p)}
\key{times at which {\tt p} reaches maximal extents}{maxtimes(p)}
\key{intersection times of paths {\tt p} and {\tt q}}{intersections(p,q)}
\key{intersection times of paths {\tt p} and {\tt a--b}}{intersections(p,a,b)}
\key{intersection times of path {\tt p} crossing $x=${\tt x}}{times(p,x)}
\key{intersection times of path {\tt p} crossing $y=${\tt z.y}}{times(p,z)}
\key{intersection point of paths {\tt p} and {\tt q}}{intersectionpoint(p,q)}
\key{intersection points of {\tt p} and {\tt q}}{intersectionpoints(p,q)}
\key{intersection of extension of {\tt P--Q} and {\tt p--q}}{extension(P,Q,p,q)}
\key{lower left point of bounding box of path {\tt p}}{min(p)}
\key{upper right point of bounding box of path {\tt p}}{max(p)}
\key{subpaths of {\tt p} split by $n$th cut of {\tt knife}}{cut(p,knife,n)}
\key{winding number of path {\tt p} about pair {\tt z}}{windingnumber(p,z)}
\key{pair {\tt z} lies within path {\tt p}?}{interior(p,z)}
\key{pair {\tt z} lies within or on path {\tt p}?}{inside(p,z)}
\key{path surrounding region bounded by paths}{buildcycle(\dots)}
\key{path filled by \tt{draw(g,p)}}{strokepath(g,p)}
\key{unit square with lower-left vertex at origin}{unitsquare}
\key{unit circle centered at origin}{unitcircle}
\key{circle of radius {\tt r} about {\tt c}}{circle(c,r)}
\key{arc of radius {\tt r} about {\tt c} from angle {\tt a} to {\tt b}}{arc(c,r,a,b)}
\key{unit {\tt n}-sided polygon}{polygon(n)}
\key{unit {\tt n}-point cyclic cross}{cross(n)}

\section{pictures}
\key{add picture {\tt pic} to currentpicture}{add(pic)}
\key{add picture {\tt pic} about pair {\tt z}}{add(pic,z)}

\section{affine transforms}
\key{identity transform}{identity()}
\key{shift by values}{shift(real,real)}
\key{shift by pair}{shift(pair)}
\key{scale by {\tt x} in the $x$ direction}{xscale(x)}
\key{scale by {\tt y} in the $y$ direction}{yscale(y)}
\key{scale by {\tt x} in both directions}{scale(x)}
\key{scale by real values {\tt x} and {\tt y}}{scale(x,y)}
\key{map $(x,y) \rightarrow (x+${\tt s}$y,y)$}{slant(s)}
\key{rotate by real {\tt angle} in degrees about pair {\tt z}}{rotate(angle,z=(0,0))}
\key{reflect about line from {\tt P--Q}}{reflect(P,Q)}

\section{string operations}
\key{concatenate operator}{+}
\key{string length}{length(string)}
\key{position $\ge$ {\tt pos} of first occurence of {\tt t} in {\tt s}}{find({\tt s},{\tt t},pos=0)}
\key{position $\le$ {\tt pos} of last occurence of {\tt t} in {\tt s}}{rfind({\tt s},{\tt t},pos=-1)}
\key{string with {\tt t} inserted in {\tt s} at {\tt pos}}{insert({\tt s},{\tt pos},{\tt t})}
\key{string {\tt s} with {\tt n} characters at {\tt pos} erased}{erase({\tt s},{\tt pos},{\tt n})}
\key{substring of string {\tt s} of length {\tt n} at {\tt pos}}{substr({\tt s},{\tt pos},{\tt n})}
\key{string {\tt s} reversed}{reverse({\tt s})}
\key{string {\tt s} with {\tt before} changed to {\tt after}}{replace({\tt s},{\tt before},{\tt after})}
\key{string {\tt s} translated via {\tt \{\{before,after\},\dots\}}}{replace({\tt
s},string [][] table)}
\key{format {\tt x} using C-style format string {\tt s} }{format({\tt s},x)}
\key{casts hexidecimal string to an integer}{hex(s)}
\key{casts {\tt x} to string using precision {\tt digits}}{string(x,digits=realDigits)}
\key{current time formatted by {\tt format}}{time(format="\%a \%b \%d \%T \%Z \%Y")}
\key{time in seconds of string {\tt t} using {\tt format}}{seconds(t,format)}
\key{string corresponding to {\tt seconds} using {\tt format}}{time(seconds,format)}
\key{split {\tt s} into strings separated by {\tt delimiter}}{split(s,delimiter="")}

%%%%%%%%%%%%%%%%%%%%%%%%%% END LIBRARIES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% This goes at the bottom of the last page (column 6)
%\copyrightnotice
%

\bye

% Local variables:
% compile-command: "tex AsyRefCard"
% End:




