PROGRAM ACMTST
C  TEST PROGRAM FOR CACM ALGORITHM 475
C  COMM ACM V17 NO3 PP152-155 (MARCH 1974)
C
C  THE FOLLOWING PARAMETERS DETERMINE THE PICTURE SIZE
C
C  LX=1+(NX-1)/NBPW, NBPW=NO OF BITS/WORD
C  ANUM1=FLOAT(NU-1) ETC., HNUP1=FLOAT(NU+1)/2. ETC.
	PARAMETER NU=50, NV=50, NW=50, NX=90, NY=90, LX=6, IU=1,
     *		ANUM1=49., ANVM1=49., ANWM1=49.,
     *		HNUP1=25.5, HNVP1=25.5, HNWP1=25.5
C  PEN COLOURS
	PARAMETER IBLACK=1, IRED=2, IGREEN=3, IBLUE=4
	BYTE OBJECT
	DIMENSION EYE(3),ST1(NU,NV,2),IS2(LX,NY),OBJECT(NV,NW)
	CALL OPENPL(2,5,'ACMTEST.PLT',-1)
	CALL LIMITS(2.5,17.5,2.5,17.5)
	OPEN(UNIT=IU, ACCESS='SEQUENTIAL', FORM='UNFORMATTED',
     *	     NAME='SY:3D.TMP', TYPE='OLD', READONLY)
	EYE(1)=250.
	EYE(2)=150.
	EYE(3)=100.
	CALL INIT3D(1,EYE,NU,NV,NW,ST1,LX,NY,IS2,IU)
	DO 50 I=1,NU
	  A=(I-31)**2
	  DO 40 J=1,NV
	    C=(J-16)**2
	    D=IABS(J-39)+IABS(I-16)
	    DO 30 K=1,NW
	      OBJECT(J,K)=0
C  FLOOR
	      IF(K.EQ.1) OBJECT(J,K)=IRED
C  BALL
	      IF(SQRT(A+C+(FLOAT(K)-16.)**2).LE.16.)
     *		OBJECT(J,K)=IBLUE
C  POINT
	      IF(D.LE.FLOAT(NW-K)*.1875) OBJECT(J,K)=IGREEN
 30	    CONTINUE
 40	  CONTINUE
	  CALL DANDR(NV,NW,ST1,LX,NX,NY,IS2,IU,OBJECT)
 50	CONTINUE
D	CALL DRAWAL
D	CALL FRAME
C  SECOND PICTURE. CALL INIT3D WITH MODE=2 TO CLEAR STORES
D	CALL INIT3D(2,EYE,NU,NV,NW,ST1,LX,NY,IS2,IU)
D	DO 120 I=1,NU
D	  U=(HNUP1-FLOAT(I))/ANUM1
D	  UU=U*U
D	  DO 110 J=1,NV
D	    V=(FLOAT(J)-HNVP1)/ANVM1
D	    VV=V*V
D	    A=1./SQRT(UU+VV)
D	    DO 100 K=1,NW
D	      IF(I*J.EQ.1 .OR. I*K.EQ.1 .OR. J*K.EQ.1) GOTO 80
D	      W=(FLOAT(K)-HNWP1)/ANWM1
D	      IF(1./SQRT(UU+VV+W*W)+(0.5-V)**2*A .LE. 4.) GOTO 90
D 80	      OBJECT(J,K)=IBLACK
D	      GOTO 100
D 90	      OBJECT(J,K)=0
D 100	  CONTINUE
D 110	CONTINUE
D	CALL DANDR(NV,NW,ST1,LX,NX,NY,IS2,IU,OBJECT)
D 120	CONTINUE
	CALL DRAWAL
	CALL GREND
 999	STOP
	END