'===========================================================================
' Subject: GEOMETRIC CIRCLE                  Date: 01-04-99 (23:33)       
' Author:  Roger Hermans                     Code: QB, QBasic, PDS, PB    
' Origin:  r.hermans@planetinternet.be     Packet: GRAPHICS.ABC
'===========================================================================
 DECLARE SUB s.WachtLus (A$)

 'for PowerBasic and QBasic.
 'Geo.bas   1/4/1999.
 'r.hermans@planetinternet.be
 'CornerR is the corner 'et tight 's with the center of the circle.
 'the value off the Cosinus is the center off the circle to the cosinus.
 'the value off the Sinus is the Cosinus to the Sinus.
 'Simplefied example off the geometric circle. The basic for triangles.
 '--------------------------------------------------------------------------

 SCREEN 12

 PI# = 4 * ATN(1): Straal = 239: CornerR = 1: px = 399: py = 240

 DO

 IF CornerR > 360 THEN CornerR = 1

 A$ = INKEY$

 CIRCLE (px, py), 239, 9

 p2x = px + Straal * COS(PI# / 180 * CornerR)
 p2y = py + Straal * SIN(PI# / 180 * CornerR)

 LINE (px - 239, py)-(px + 239, py), 2        'de 2 haakse lijnen.
 LINE (px, py + 239)-(px, py - 239), 2

 LINE (px, py)-(p2x, p2y), 15               'de straal.
 LINE (px, py)-(p2x, py), 15                'de cos lijn.
 LINE (p2x, py)-(p2x, p2y), 15              'de sin lijn.

 LOCATE 1, 1: PRINT "Cosinus ="; ABS(Straal * COS(PI# / 180 * CornerR))
 LOCATE 3, 1: PRINT "Sinus ="; ABS(Straal * SIN(PI# / 180 * CornerR))

 LOCATE 5, 1: PRINT "CornerR ="; CornerR

 IF CornerR > 90 AND CornerR < 180 THEN
   LOCATE 5, 14: PRINT "("; 180 - CornerR; ")"
 ELSEIF CornerR > 180 AND CornerR < 270 THEN
   LOCATE 5, 14: PRINT "("; ABS((270 - CornerR) - 90); ")"
 ELSEIF CornerR > 270 AND CornerR < 360 THEN
   LOCATE 5, 14: PRINT "("; 360 - CornerR; ")"
 END IF

 LOCATE 1, 73: PRINT "Cosinus"
 LINE (605, 15)-(p2x, py), 12

 LOCATE 26, 1: PRINT "Sinus"
 LINE (40, 408)-(p2x, p2y), 4

 LOCATE 28, 72: PRINT "Esc = end"
 LOCATE 28, 1: PRINT "Push a button"

 s.WachtLus A$

 COLOR 15
 CLS

 CornerR = CornerR + 1           'for QBasic fans.

 IF A$ = CHR$(27) THEN
  LOCATE 4, 10: PRINT "Roger Hermans  - Geo1.bas -"
   LOCATE 6, 10: PRINT "r.hermans@planetinternet.be"
     LOCATE 8, 10: PRINT " See You on the Internet."
   END
 END IF

 LOOP

 '---------------------------------------------------------------------------

 SUB s.WachtLus (A$)

 DO
  A$ = INKEY$
   IF A$ <> "" THEN EXIT DO
    COLOR 11
   LOCATE 16, 1
  PRINT TIME$
 LOOP

 END SUB