§ Код программы

SCREEN 13

DrawGrid
DrawText

cx% = 0: cy% = 0
dx% = 0: dy% = 0

LOCATE 2, 19: PRINT "S-Save font.bin"
LOCATE 3, 19: PRINT "L-Load font.bin"

mode = 1

DO

  UpdateGrid cx%, cy%, 1
  IF mode = 0 THEN SetGrid dx%, dy%, 15

  DO: i$ = INKEY$: LOOP WHILE i$ = ""

  lf = 0: rt = 0: up = 0: dn = 0
  IF i$ = CHR$(0) + "K" THEN lf = 1
  IF i$ = CHR$(0) + "M" THEN rt = 1
  IF i$ = CHR$(0) + "H" THEN up = 1
  IF i$ = CHR$(0) + "P" THEN dn = 1
  IF i$ = "s" OR i$ = "S" THEN SaveFont
  ' MODE = 0: Draw 8x8 Block
  IF mode = 0 THEN

    SetGrid dx%, dy%, 8

    IF lf AND dx% > 0 THEN dx% = dx% - 1
    IF rt AND dx% < 7 THEN dx% = dx% + 1
    IF up AND dy% > 0 THEN dy% = dy% - 1
    IF dn AND dy% < 7 THEN dy% = dy% + 1

    IF i$ = CHR$(27) THEN mode = 1: i$ = ""

    ' Swap color
    IF i$ = " " THEN

      ax = 8 + 8 * cx% + dx%
      ay = 80 + 8 * cy% + dy%
      n = POINT(ax, ay)
      k = n <> 8 AND n <> 0
      IF k THEN c = 8 ELSE c = 15
      PSET (ax, ay), c

    END IF

  ELSE

    UpdateGrid cx%, cy%, 0

    IF lf AND cx% > 0 THEN cx% = cx% - 1
    IF rt AND cx% < 31 THEN cx% = cx% + 1
    IF up AND cy% > 0 THEN cy% = cy% - 1
    IF dn AND cy% < 7 THEN cy% = cy% + 1

    IF i$ = CHR$(13) THEN mode = 0: i$ = ""

  END IF

LOOP UNTIL i$ = CHR$(27) AND mode = 1

SUB DrawGrid

  ox = 8
  oy = 8

  FOR y = 0 TO 7
  FOR x = 0 TO 7
    LINE (ox + 8 * x, oy + 8 * y)-(ox + 8 * x + 8, oy + 8 * y + 8), 8, B
  NEXT
  NEXT

END SUB

SUB DrawText

  COLOR 7
  FOR y = 1 TO 7
  FOR x = 0 TO 31
    LOCATE 10 + y, x + 2: PRINT CHR$(x + 32 * y);
  NEXT
  NEXT

END SUB

SUB SaveFont

OPEN "font.bin" FOR OUTPUT AS #1
FOR i = 0 TO 255: PRINT #1, CHR$(0); : NEXT
FOR y = 0 TO 6
FOR x = 0 TO 31
FOR i = 0 TO 7
t = 0
FOR j = 0 TO 7

  n = POINT(8 + x * 8 + j, 80 + y * 8 + i)
  k = n <> 8 AND n <> 0
  t = t * 2
  IF k THEN t = t + 1

NEXT
PRINT #1, CHR$(t);
NEXT
NEXT
NEXT
CLOSE #1
END SUB

SUB SetGrid (x%, y%, c)
  LINE (8 + x% * 8, 8 + y% * 8)-(8 + x% * 8 + 8, 8 + y% * 8 + 8), c, B
END SUB

SUB UpdateGrid (x%, y%, t%)

  ox = 8
  oy = 80

  FOR i = 0 TO 7
  FOR j = 0 TO 7

    ax = ox + j + x% * 8
    ay = oy + i + y% * 8
    a = POINT(ax, ay)
    k = (a <> 8) AND (a <> 0)

    IF k THEN c = 7 ELSE c = 0

    IF t% > 0 THEN
      IF k THEN B = 15 ELSE B = 8
    ELSE
      IF k THEN B = 7 ELSE B = 0
    END IF

    PSET (ax, ay), B

    LINE (8 + 8 * j + 1, 8 + 8 * i + 1)-(8 + 8 * j + 7, 8 + 8 * i + 7), c, BF

  NEXT
  NEXT

END SUB