doc-en/par-codejps-en.tex

   1 \section{The \Index{jps code}}
   2
   3 \textit{jps code} contains all the  PostScript code that is used by the library
   4 developed for the software \textit{jps2ps}.
   5
   6 The \texttt{solides.pro} file of the \texttt{solides3d} package
   7 contains all the elements native
   8 to that library, which contains about $4\, 500$~functions and
   9 procedures.
  10
  11 It allows us to have available some adapted commands in mathematical form, without
  12 having to construct them with the primitives
  13  \verb+moveto+, \verb+lineto+, \verb+curveto+, etc.
  14
  15 For example, we can define a function $F$ with $F(t) =
  16 (3\cos^3 t, 3\sin^3 t)$, and draw its curve
  17 %I'm not sure of the distinction between the curve and the path, as you use it
  18 with the \textit{jps code} \verb+0 360 {F} CourbeR2+.
  19
  20 If we only want to have the path of that curve, we use the code
  21 \verb+0 360 {F} CourbeR2_+,
  22 and if we want to add this to the stack of points of the curve,
  23 we use \verb+0 360 {F} CourbeR2++.
  24
  25 In all of the $3$~examples below, the number of points is declared by the global
  26 variable \Lkeyword{resolution}.
  27
  28 In other words, with the \Index{function} $F$ named above and a fixed resolution of 36, the \textit{jps code}
  29 \begin{verbatim}
  30    0 360 {F} CourbeR2+
  31 \end{verbatim}
  32 is equivalent to the PostScript code
  33 \begin{verbatim}
  34    0 10 360 {
  35       /angle exch def
  36       3 angle cos 3 exp mul
  37       3 angle sin 3 exp mul
  38    } for
  39 \end{verbatim}
  40
  41 We haven't yet developed documentation for the library hidden in the
  42 \texttt{solides.pro} file. For the moment we refer the
  43 \textit{Guide de l'utilisateur de jps2ps} for the interested user
  44 available at the website  \url{melusine.eu.org/syracuse/bbgraf}.
  45
  46 \endinput