'===========================================================================
' Subject: CIRCLE FUNCTIONS                   Date: 12-17-95 (11:37)       
'  Author: Mike Beckman                       Code: QB, QBasic, PDS        
'  Origin: mhscards@aol.com                 Packet: EGAVGA.ABC
'===========================================================================
DEFINT A-Z
DECLARE FUNCTION Distance! (x1, y1, x2, y2)
SCREEN 12

DO
   CLS
   PRINT "You must choose at least 2 points."
   INPUT "How many points do you want the computer to choose randomly"; a
   IF a > 1 THEN EXIT DO
LOOP

PRINT
PRINT "Do you want the computer to choose the center of the circle,"
PRINT "or would you like to choose it?"
PRINT "(Press C for computer to choose or anything else to choose)"
DO: abc$ = INKEY$: LOOP UNTIL abc$ <> ""
PRINT abc$
IF INSTR("cC", abc$) THEN
   RANDOMIZE TIMER
   x = INT(RND * 640)
   y = INT(RND * 480)
   radius = INT(RND * 200) + 20
ELSE
   DO
      INPUT "X Coordinate"; x
      IF x >= 0 AND x <= 639 THEN EXIT DO
   LOOP
   DO
      INPUT "Y Coordinate"; y
      IF y >= 0 AND x <= 479 THEN EXIT DO
   LOOP
   DO
      INPUT "Radius (20 - 220)"; radius
      IF radius >= 20 OR radius <= 220 THEN EXIT DO
   LOOP
END IF

PRINT "Now choosing random points..."

   RANDOMIZE TIMER
   DIM x1(1 TO a)
   DIM y1(1 TO a)

FOR ab = 1 TO a
   x1(ab) = INT(RND * 640)
   y1(ab) = INT(RND * 480)
NEXT ab

PRINT "Done!"
PRINT
PRINT "Now I'm going to draw the screen."
PRINT "The circle will be blue, the center of the circle will be red, and"
PRINT "all the points will be yellow."
PRINT
PRINT "Then I will tell you how many points are on the circle, how many"
PRINT "are inside the circle, and how many are outside the circle."
DO: LOOP UNTIL LEN(INKEY$)

CLS

FOR ab = 1 TO a
   PSET (x1(ab), y1(ab)), 14
NEXT ab

CIRCLE (x, y), radius, 9

DO: LOOP UNTIL LEN(INKEY$)

CLS
inside = 0
outside = 0
oncircle = 0
timey! = TIMER
FOR ab = 1 TO a
   dist! = Distance(x, y, x1(ab), y1(ab))
   IF dist! = radius THEN oncircle = oncircle + 1
   IF dist! > radius THEN outside = outside + 1
   IF dist! < radius THEN inside = inside + 1
NEXT ab
stoptime! = TIMER - timey!

SCREEN 0
PRINT "Total Points on the screen:"; a
PRINT "Total Points on the circle:"; oncircle
PRINT "Total Points outside the circle:"; outside
PRINT "Total Points inside the circle:"; inside
PRINT "Radius of the circle:"; radius
PRINT "Seconds to calculate:"; stoptime!
END

FUNCTION Distance! (x1, y1, x2, y2)

Distance! = SQR((x2 - x1) ^ 2 + (y2 - y1) ^ 2)

END FUNCTION