% Copyright 2005 by Palle Jørgensen
%
% This file is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation; either version 2 of the License, or
% (at your option) any later version.
%
% This program 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.  See the GNU
% General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc., 59 Temple Place - Suite 330, Boston,
% MA 02111-1307, USA.
%
% This is version 0.1 Wed Aug 10 2005
%
% The module is documentet in exteps.pdf

picture epspicture; 

%% String handling tool
string string_split[];
def splitstring expr S =
  begingroup
    save __splitctr; numeric __splitctr; __splitctr = 0;
    save __prevchar; string __prevchar, __currentchar; __prevchar = " ";
    for i = 0 upto infinity:
      __currentchar := substring(i, i+1) of S;
      if (__currentchar = " ") and (__prevchar = " "):
	relax;
      elseif (__currentchar <> " ") and (__prevchar = " "):
	string_split[__splitctr] := __currentchar;
      elseif (__currentchar <> " ") and (__prevchar <> " "):
	string_split[__splitctr] := string_split[__splitctr] & __currentchar;
      elseif (__currentchar = " ") and (__prevchar <> " "):
	__splitctr := __splitctr+1;
      fi
      __prevchar := __currentchar;
    endfor
  endgroup;
enddef;
%% End string handling tool

def begineps text F =
  begingroup;
    save file;                string file;        file = F;    
    save angle;               numeric angle;      angle = 0;
    save clip;                boolean clip;       clip = false;
    save scale;               pair scale;         scale = (1,1);
    save base;                pair base;          base = origin;
    save __bbxfound;          boolean __bbxfound; __bbxfound = false;
    save grid;                boolean grid;       grid = false;
    save gridstep;            numeric gridstep;   gridstep = 10;
    save __base;              pair __base;
    save  __eps__currentline; string __eps__currentline;
    save __bbxline;           string __bbxline;
    save llx, lly, urx, ury;  numeric llx, lly, urx, ury;
    save pct;                 numeric pct;
    save width;               numeric width;
    save height;              numeric height;
%% Finding the bounding box
    forever:
      __eps__currentline := readfrom F;
      if substring(0,14) of __eps__currentline = "%%BoundingBox:":
	__bbxline := substring(14, infinity) of __eps__currentline;
	__bbxfound := true;
	splitstring __bbxline;
	llx = scantokens string_split[0];
	lly = scantokens string_split[1];
	urx = scantokens string_split[2];
	ury = scantokens string_split[3];
      fi
      exitif __bbxfound;
    endfor
    closefrom F;
    __base = -(llx,lly);
    pct = (urx - llx)/100;
%% To ensure the right bounding box of the output file
%% a picture with the same size as the eps figure is added.
    epspicture := nullpicture;
    setbounds epspicture to ((0,0)--(0,ury-lly)--(urx-llx,ury-lly)--(urx-llx,0)--cycle);
enddef;
  
def endeps =
%% Drawing the grid
  if grid:
    for i = 0 step gridstep*pct until (urx - llx):
      epsdraw (i,0)--(i,ury - lly);
      epslabel.bot(((decimal.(i/pct) & "%") infont defaultfont) rotated -90, (i,0));
    endfor
    for i = 0 step gridstep*pct until (epsilon + ury - lly):
      epsdraw (0,i)--(urx - llx,i);
      epslabel.lft(((decimal.(i/pct) & "%") infont defaultfont), (0,i));
    endfor
  fi
%% Calculating scale if width and/or height is known
  if (known width) and (known height):
    scale := (width/(urx - llx),height/(ury - lly));
  elseif known width:
    scale := (width/(urx - llx),width/(urx - llx));
  elseif known height:
    scale := (height/(ury - lly),height/(ury - lly));
  fi
%% The graphics inclusion commands
  special "gsave";
  if base <> origin:
    special decimal.xpart.base & " " & decimal.ypart.base & " translate";
  fi
  if scale <> (1,1):
    special decimal xpart.scale & " " & decimal ypart.scale & " scale";
  fi
  if angle <> 0:
    special decimal angle & " rotate";
    epspicture := epspicture rotatedaround(origin)(angle);
  fi
    if __base <> origin:
    special decimal.xpart.__base & " " & decimal.ypart.__base & " translate";
  fi
  if scale <> (1,1):
    epspicture := epspicture scaled xpart.scale
    if xpart.scale <> ypart.scale:
      yscaled (ypart.scale/xpart.scale)
    fi;
  fi
  if clip:
    special "newpath ";
    special decimal llx & " " & decimal lly & " moveto";
    special decimal llx & " " & decimal ury & " lineto";
    special decimal urx & " " & decimal ury & " lineto";
    special decimal urx & " " & decimal lly & " lineto";
    special decimal llx & " " & decimal lly & " lineto";
    special "closepath clip";
  fi
  special "%%BeginDocument: " & file;
  forever:
    __eps__currentline := readfrom file;
    exitunless __eps__currentline <> EOF;      
    special __eps__currentline;
  endfor
  special "%%EndDocument: " & file;
  special "grestore";
  closefrom file;
  if base <> (0,0):
    epspicture :=  epspicture shifted base;
  fi
  addto currentpicture also epspicture;
endgroup;
enddef;

%% Special drawing commands
def epsfill expr c = addto epspicture contour c _op_ enddef;

def epsdraw expr p =
  addto epspicture
  if picture p:
    also p
  else:
    doublepath p withpen currentpen
  fi
  _op_
enddef;

def epsfilldraw expr c =
  addto epspicture contour c withpen currentpen
  _op_ enddef;

def epsdrawdot expr z =
  addto epspicture contour makepath currentpen shifted z
  _op_ enddef;

def epslabel = epsdraw thelabel enddef;

endinput