PACKET graphic editor DEFINES  graphic,           (*Autor: H.Indenbirken *)
                               picfile, picture,  (*Stand: 26.02.1985    *)

                               neu zeichnen,
 
                               UP, DOWN, T,

                               pen, select pen, selected pen, background,
                               extrema pic, extrema picfile:
 

 
LET norm cmd = ""1""27""3""10""9"epb"16"",
    hop cmd = ""2""10""12""1"",
    bell    = ""7"",
    esc     = ""27"";

PICFILE VAR p;
PICTURE VAR pic;
TEXT VAR command :: "", old command :: "", char, headline :: "";
BOOL VAR within edit :: FALSE, new plot :: FALSE;
ROW 3 ROW 2 REAL VAR size;
ROW 2 ROW 2 REAL VAR limits;
ROW 4 REAL VAR angles;
ROW 2 REAL VAR oblique;
ROW 3 REAL VAR perspective;

PROC open graphic (TEXT CONST name, DATASPACE CONST ds):
  p := ds; 
  get values (p, size, limits, angles, oblique, perspective); 
  head line := ""1""15"LEN       ................................ DIM    PEN    .."14" Picture      "15""14"";
  replace (head line, 32-LENGTH name DIV 2, name);
  new plot := TRUE;
  within edit := TRUE
END PROC open graphic;

PROC graphic:
  graphic (last param)
END PROC graphic;

PROC graphic (TEXT CONST name) :
  IF NOT exists (name) 
  THEN IF yes ("Soll ein neuer Picfile eingerichtet werden")
       THEN graphic (new (name), name) FI
  ELSE graphic (old (name), name) FI

END PROC graphic;

PROC graphic (DATASPACE CONST f, TEXT CONST name) :
  open graphic (name, f);
  reset;
  kommandos bearbeiten;
  within edit := FALSE  .

kommandos bearbeiten :
  REP IF new plot
      THEN plot (p);
           new plot := FALSE
      FI;
      read picture (p, pic);
      out head line;
      inchar (command);
      do command
  PER  .
 
out head line:
  replace (headline,  7, text (length (pic), 5));
  replace (headline, 50, text (dim (pic), 1));
  replace (headline, 57, text (pen (pic), 2));
  replace (headline, 72, text (picture no (p), 4));
  out (head line)  .

do command:
  SELECT pos (norm cmd, command) OF 
  CASE  1: hop commands
  CASE  2: escape commands
  CASE  3: position up
  CASE  4: position down
  CASE  5: position direct
  CASE  6: extrema pic
  CASE  7: selected pen (pen (pic));
  CASE  8: out (1, 2, ""15""5"Hintergrundfarbe: " +
           colour of (background (p)) + " "14"")
  CASE  9: identify (pic);
  OTHERWISE out (bell) ENDSELECT .

position up :
  IF is first picture (p)
  THEN out (bell);
  ELSE up (p) FI  .

position down :
  IF eof (p)
  THEN out (bell)
  ELSE down (p) FI  .
 
position direct:
   out (1, 68, "");
   edit get (command, 4, 4);
   to pic (p, int (command))  .

hop commands :
  inchar (command);
  SELECT pos (hop cmd, command) OF 
  CASE 1: to first pic (p)
  CASE 2: to eof (p)
  CASE 3: delete picture (p);
          IF NOT new plot
          THEN erase (pic) FI
  CASE 4: new plot := TRUE
  OTHERWISE out (bell) ENDSELECT  .

escape commands :
  inchar (command);
  IF command = "q"
  THEN LEAVE kommandos bearbeiten
  ELIF command = "f"
  THEN do (old command)
  ELIF command = esc
  THEN kommandomodus
  ELSE do (kommando auf taste (command)) FI  .

END PROC graphic;

PROC kommandomodus:
  command := "";
  disable stop;
  REP get command;
      do (command)
  UNTIL command executed PER;

  IF new values
  THEN get values (size, limits, angles, oblique, perspective); 
       set values (p, size, limits, angles, oblique, perspective); 
       new plot := new plot OR new values
  FI  .

get command:
  REP out (1, 2, ""15"Gib Graphikkommando: ");
      edit get (command, 0, 54, "", "k", char);
      out (""14"");
      out (1, 2, ""5"");

      IF char = ""13""
      THEN LEAVE get command
      ELIF char = ""27"k"
      THEN command := old command FI
  PER  .

command executed:
  IF is error
  THEN out (1, 1, error message);
       clear error;
       FALSE
  ELSE old command := command;
       TRUE
  FI  .

END PROC kommandomodus;

PROC out (INT CONST x, y, TEXT CONST t):
  cursor (x, y);
  out (t)
END PROC out;

TEXT PROC colour of (INT CONST colour):
  SELECT colour OF
  CASE 0: "löschen"
  CASE 1: "std"
  CASE 2: "rot"
  CASE 3: "blau"
  CASE 4: "grün"
  CASE 5: "schwarz"
  CASE 6: "weiß"
  OTHERWISE text (colour) ENDSELECT  .
END PROC colour of;

TEXT PROC linetype of (INT CONST linetype):
  SELECT linetype OF
  CASE 0: "unsichtbar"
  CASE 1: "durchgehend"
  CASE 2: "gepunktet"
  CASE 3: "kurz gestrichelt"
  CASE 4: "lang gestrichelt"
  CASE 5: "strichpunkt"
  OTHERWISE text (linetype) ENDSELECT  .
END PROC linetype of;

PICFILE PROC picfile :
  IF NOT within edit
  THEN errorstop ("Not within editmode") FI;
  p
END PROC picfile;

PICTURE PROC picture :
  IF NOT within edit
  THEN errorstop ("Not within editmode") FI;
  pic
END PROC picture;

PROC neu zeichnen:
  new plot := TRUE
END PROC neu zeichnen;

OP UP (INT CONST distance):
  up (p, distance);
  read picture (p, pic) 
END OP UP;

OP DOWN (INT CONST distance):
  down (p, distance);
  read picture (p, pic) 
END OP DOWN;

OP T (INT CONST n):
  to pic (p, n);
  read picture (p, pic) 
END OP T;
 
PROC pen (INT CONST n):
  IF NOT new plot
  THEN erase (pic) FI;

  pen (pic, n);
  write picture (p, pic);

  IF NOT new plot
  THEN show (pic) FI
END PROC pen;

PROC select pen (INT CONST n, colour, thickness, linetype, BOOL CONST hidden):
  select pen (p, n, colour, thickness, linetype, hidden);
  new plot := TRUE
END PROC select pen;

PROC select pen (INT CONST n, colour, thickness, linetype):
  select pen (p, n, colour, thickness, linetype, FALSE);
  new plot := TRUE
END PROC select pen;

PROC selected pen (INT CONST n, INT VAR colour, thickness, linetype,
                   BOOL VAR hidden):
  selected pen (p, n, colour, thickness, linetype, hidden);
END PROC selected pen;

PROC selected pen (INT CONST n):
  INT VAR colour, thickness, linetype;
  BOOL VAR hidden;
  selected pen (p, n, colour, thickness, linetype, hidden);
  out (1, 2, ""5""15"PEN #" + text (n) + ":  Farbe: " + colour of (colour) +
             ", Dicke " + text (thickness) + ", Linientyp " + linetype of (linetype) +
             hidden text + " "14"")  .

hidden text:
  IF hidden
  THEN ". "
  ELSE ", nicht sichtbare Linien werden unterdrückt." FI  .

END PROC selected pen;

INT PROC background:
  background (p)
END PROC background;

PROC background (INT CONST n):
  new plot := n <> background (p);
  background (p, n)
END PROC background;

PROC extrema pic:
  REAL VAR x min, x max, y min, y max, z min, z max;
  IF dim (pic) = 2
  THEN extrema (pic, x min, x max, y min, y max);
       out (1, 2, ""5""15"Extrema: [" + text (x min) + "," + text (x max) + 
                  "]  [" + text (y min) + "," + text (y max) + "] "14"")
  ELSE extrema (pic, x min, x max, y min, y max, z min, z max);
       out (1, 2, ""5""15"Extrema: [" + text (x min) + "," + text (x max) + 
                  "]  [" + text (y min) + "," + text (y max) + 
                  "]  [" + text (z min) + "," + text (z max) +"] "14"") 
  FI
END PROC extrema pic;

PROC extrema picfile:
  REAL VAR x min, x max, y min, y max, z min, z max;
  extrema (p, x min, x max, y min, y max, z min, z max);
  out (1, 2, ""5""15"Extrema: [" + text (x min) + "," + text (x max) + 
             "]  [" + text (y min) + "," + text (y max) + 
             "]  [" + text (z min) + "," + text (z max) +"] "14"") 
END PROC extrema picfile;

PROC identify (PICTURE CONST pic):
  begin plot;
  hidden lines (TRUE);
  pen (background (p), 1, 1, 2);
  plot (pic);
  end plot
END PROC identify;

PROC erase (PICTURE CONST pic):
  INT VAR colour, thickness, linetype;
  BOOL VAR hidden;

  selected pen (p, pen (pic), colour, thickness, linetype, hidden); 
  begin plot;
  hidden lines (TRUE);
  pen (background (p), 0, thickness, linetype);
  plot (pic);
  end plot
END PROC erase;

PROC show (PICTURE CONST pic):
  INT VAR colour, thickness, linetype;
  BOOL VAR hidden;

  selected pen (p, pen (pic), colour, thickness, linetype, hidden); 
  begin plot;
  hidden lines (TRUE);
  pen (background (p), colour, thickness, linetype);
  plot (pic);
  end plot
END PROC show;

END PACKET graphic editor;