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PACKET std plot DEFINES drawing area,
begin plot,
end plot,
clear,
pen,
move,
draw,
get cursor:
LET delete = 0, {Farbcodes}
std = 1,
black = 5,
white = 6,
durchgehend = 1, {Linientypen}
gepunktet = 2,
kurz gestrichelt = 3,
lang gestrichelt = 4,
strichpunkt = 5,
empty = 0, {Punktsymbole}
high = 1,
low = 2,
both = 3;
LET POS = STRUCT (INT x, y);
ROW 79 ROW 24 INT VAR screen;
BOOL VAR colour :: TRUE, action :: TRUE;
POS VAR pos :: POS : (0, 0);
clear;
PROC drawing area (REAL VAR x cm, y cm, INT VAR x pixel, y pixel) :
x cm := 25.0; y cm := 17.0; {***** Horizontale und vertikale *****}
{***** GrӇe in Zentimetern. *****}
x pixel := 79; y pixel := 48 {***** Koordinaten des rechten *****}
{***** oberen Punktes. *****}
END PROC drawing area;
PROC begin plot :
ENDPROC begin plot ;
PROC end plot :
ENDPROC end plot ;
PROC clear :
INT VAR i, j;
colour := TRUE;
action := TRUE;
pos := POS : (0, 0);
FOR i FROM 1 UPTO 24
REP screen [1] [i] := 0 PER;
FOR i FROM 2 UPTO 79
REP screen [i] := screen [1] PER;
page;
out (""6""23""0"") .
END PROC clear;
PROC pen (INT CONST background, foreground, thickness, linetype):
colour := foreground > 0;
action := linetype <> 0 .
END PROC pen;
PROC move (INT CONST x, y) :
out (""6""+ code (23-y DIV 2) + code (x));
pos := POS : (x, y)
END PROC move;
PROC draw (INT CONST x, y) :
IF action
THEN vector (x-pos.x, y-pos.y) FI;
pos := POS : (x, y) .
END PROC draw;
PROC vector (INT CONST dx , dy) :
IF dx >= 0
THEN IF dy > dx THEN vector (pos.y, pos.x, dy, dx, 1, 1)
ELIF dy > 0 THEN vector (pos.x, pos.y, dx, dy, 1, 1)
ELIF dy > -dx THEN vector (pos.x, pos.y, dx, -dy, 1,-1)
ELSE vector (pos.y, pos.x, -dy, dx,-1, 1) FI
ELSE IF dy > -dx THEN vector (pos.y, pos.x, dy, -dx, 1,-1)
ELIF dy > 0 THEN vector (pos.x, pos.y, -dx, dy,-1, 1)
ELIF dy > dx THEN vector (pos.x, pos.y, -dx, -dy,-1,-1)
ELSE vector (pos.y, pos.x, -dy, -dx,-1,-1) FI
FI .
ENDPROC vector ;
PROC vector (INT VAR x pos, y pos, INT CONST dx, dy, right, up) :
INT VAR i;
prepare first step ;
point;
FOR i FROM 1 UPTO dx
REP do one step PER .
prepare first step :
INT VAR up right error := dy - dx,
right error := dy,
old error := 0 .
do one step:
IF right is better
THEN do right step
ELSE do up right step
FI .
right is better :
abs (old error + right error) < abs (old error + up right error) .
do upright step :
x pos INCR right ;
y pos INCR up ;
point ;
old error INCR upright error .
do right step :
x pos INCR right ;
point ;
old error INCR right error .
point :
IF (pos.y AND 1) = 0
THEN lower point
ELSE upper point FI .
lower point :
out (""6""+ code (23-pos.y DIV 2) + code (pos.x));
IF colour
THEN set lower point
ELSE reset lower point FI .
set lower point:
SELECT screen [pos.x+1] [pos.y DIV 2+1] OF
CASE empty : out (","8"");
screen [pos.x+1] [pos.y DIV 2+1] := low
CASE high : out ("|"8"");
screen [pos.x+1] [pos.y DIV 2+1] := both
ENDSELECT .
reset lower point:
SELECT screen [pos.x+1] [pos.y DIV 2+1] OF
CASE low : out (" "8"");
screen [pos.x+1] [pos.y DIV 2+1] := empty
CASE both : out ("'"8"");
screen [pos.x+1] [pos.y DIV 2+1] := high
ENDSELECT .
upper point :
out (""6""+ code (23-pos.y DIV 2) + code (pos.x));
IF colour
THEN set upper point
ELSE reset upper point FI .
set upper point:
SELECT screen [pos.x+1] [pos.y DIV 2+1] OF
CASE empty : out ("'"8"");
screen [pos.x+1] [pos.y DIV 2+1] := high
CASE low : out ("|"8"");
screen [pos.x+1] [pos.y DIV 2+1] := both
ENDSELECT .
reset upper point:
SELECT screen [pos.x+1] [pos.y DIV 2+1] OF
CASE high : out (" "8"");
screen [pos.x+1] [pos.y DIV 2+1] := empty
CASE both : out (","8"");
screen [pos.x+1] [pos.y DIV 2+1] := low
ENDSELECT .
END PROC vector;
PROC draw (TEXT CONST record, REAL CONST angle, height, width):
out (subtext (record, 1, 79-pos.x));
out (""6""+ code (23-pos.y DIV 2) + code (pos.x));
END PROC draw;
PROC draw (TEXT CONST record) :
draw (record, 0.0, 0.0, 0.0)
END PROC draw;
PROC get cursor (TEXT VAR t, INT VAR x, y) :
x := pos.x;
y := pos.y;
REP out (""6""+ code (23-y DIV 2) + code (x));
inchar (t);
SELECT code (t) OF
CASE 2 : x INCR 1
CASE 3 : y INCR 1
CASE 8 : x DECR 1
CASE 10: y DECR 1
CASE 1 : out (""0""1"" + text (x, 3) + "," + text (y, 3) + " "13""16"")
OTHERWISE leave get cursor ENDSELECT;
check
PER .
leave get cursor:
out (""6""+ code (23-pos.y DIV 2) + code (pos.x));
LEAVE get cursor .
check :
IF x < 0
THEN x := 0;
out (""7"")
ELIF x > 47
THEN x := 47;
out (""7"")
FI;
IF y < 0
THEN y := 0;
out (""7"")
ELIF y > 78
THEN y := 78;
out (""7"")
FI .
END PROC get cursor;
PROC test (INT CONST x, y, TEXT CONST t):
out (""27";(" + text (x) + "," + text (y) + ") " + t + ""29"");
IF incharety (10000) = ""27""
THEN stop FI
END PROC test;
END PACKET std plot;
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