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DRAW Statement Programming Example
                       Example                 Contents  Index  Back
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'The following three examples demonstrate the DRAW statement.
 
'This example uses the DRAW statement to draw a triangle's outline in magenta
'and to paint the interior cyan.
 
SCREEN 1
DRAW "C2"             'Set color to magenta.
DRAW "F60 L120 E60"   'Draw a triangle.
DRAW "BD30"           'Move down into the triangle.
DRAW "P1,2"           'Paint interior.
 
 
'The following example shows how to use the M macro command with absolute and
'relative movement, and with string-variable and numeric-variable arguments.
 
SCREEN 2
PRINT "Press any key to continue..."
'Absolute movement.
DRAW "M 50,80"
DRAW "M 80,50"
LOCATE 2, 30: PRINT "Absolute movement"
DO
LOOP WHILE INKEY$ = ""
'Relative movement.
DRAW "M+40,-20"
DRAW "M-40,-20"
DRAW "M-40,+20"
DRAW "M+40,+20"
LOCATE 3, 30: PRINT "Relative movement"
DO
LOOP WHILE INKEY$ = ""
'Using a string variable.
X$ = "400": Y$ = "190"
DRAW "M" + X$ + "," + Y$
LOCATE 4, 30: PRINT "String variable"
DO
LOOP WHILE INKEY$ = ""
'Using numeric variables (note the two "=" signs).
A = 300: B = 120
DRAW "M=" + VARPTR$(A) + ",=" + VARPTR$(B)
LOCATE 5, 30: PRINT "Numeric variables"
 
 
'This example draws a clock on the screen using the TIME$ function.
 
DECLARE SUB Face (Min$)
SCREEN 2    '640 x 200 pixel high-resolution graphics screen.
DO
   CLS
   'Get string containing minutes value.
   Min$ = MID$(TIME$, 4, 2)
   'Draw clock face.
   Face Min$
   'Wait until minute changes or a key is pressed.
   DO
      'Print time at top of screen.
      LOCATE 2, 37
      PRINT TIME$
      'Test for a key press.
      Test$ = INKEY$
   LOOP WHILE Min$ = MID$(TIME$, 4, 2) AND Test$ = ""
'End program when a key is pressed.
LOOP WHILE Test$ = ""
END
 
'Draw the clock face.
SUB Face (Min$) STATIC
   LOCATE 23, 30
   PRINT "Press any key to end"
   CIRCLE (320, 100), 175
   'Convert strings to numbers.
   Hr = VAL(TIME$)
   Min = VAL(Min$)
   'Convert numbers to angles.
   Little = 360 - (30 * Hr + Min / 2)
   Big = 360 - (6 * Min)
   'Draw the hands.
   DRAW "TA=" + VARPTR$(Little) + "NU40"
   DRAW "TA=" + VARPTR$(Big) + "NU70"
END SUB