00002	C***** FILLER, HGHT, MISS, HALF ********
00005	C  Q AND R  ARE X,Y COORDS.  NE(1)=WDCNT. OTHER NE'S HAVE 3
00007	C   FOR INVIS. VECTORS.   M=VERTICAL SCAN LINES
00010		SUBROUTINE FILLER(Q,R,NE,M)
00200		DIMENSION Q(1),R(1),NE(1)
00500		KK=NE(1)
00510		NX=-10000
00520		JN=NX
00600		KJ=2
00700		DO 4 K=2,KK
00800		IF(NE(K).NE.3)GO TO 11
00900		NE(K)=KJ
01000		KJ=K+1
01100		GO TO 4
01200	11	NE(K)=0
01300	4	CONTINUE
01310		DO 12 K=1,KK
01320		Q(K)=IFIX(Q(K))
01330	12	R(K)=IFIX(R(K))
01400		NE(KK+1)=KJ
01500	C  FINDS JUMPS
02200		DO 2 J=2,KK
02300		IF(NE(J).GT.0.OR.Q(J).EQ.Q(J-1))GO TO 2
02400	C  SKIPS VERTICAL LINES
02410		XMID=HALF(Q,J)+.00001
02500	C  MIDPOINT OF LINE
02600		ALT=HALF(R,J)
02700	C  THE ALTITUDE
02800		KJ=0
02810	
02900	100	DO 3 L=2,KK
03000		IF(L.EQ.J.OR.NE(L).GT.0)GO TO 3
03100	C  NEXT FINDS LINE OVERLAP
03205		IF(MISS(L,XMID,Q))GO TO 3
03800	C  NEXT FINDS ALT. OF CROSSING
03900	40	Y=HGHT(L,XMID,Q,R)
04000		IF(Y.LT.ALT)KJ=KJ+1
04100	3	CONTINUE
04110	
04200		IF(MOD(KJ,2).EQ.0)GO TO 2
04300	C  NEXT IF FOUND A LINE TO DRAW LINES DOWN FROM.
04400		NE(J)=-1
05215		KJ=M
05235		N=Q(J)
05255		L=Q(J-1)
05256	CC	IF(IABS(N-L).LE.M)GO TO 2
05257	C  SKIPS SEGS SHORTER THAN M INCREMENT.
05258		ALT=.0001
05260		IF(N.GT.L)GO TO 33
05270		KJ=-KJ
05275		ALT=-ALT
05280	33	IF(L.EQ.NX.AND.JN.EQ.J-1)GO TO 17
05285		JA=3
05290		X=-1
05295	17	NX=N
05296		JN=J
05346	
05396	CC34	L=L+KJ/2
05408		DO 6 K=L,N,KJ
05414		RK=K
05420		XK=RK
05426		IF(K.EQ.N)ALT=-ALT
05433	C  NO SHIFT AT LAST POSITION
05466	 	RK=RK+ALT
05501		Y=HGHT(J,RK,Q,R)
05605	CC1000	YK=Y-1
05611		IF(X)CALL LINES(XK,Y,JA)
05620		JA=2
05700		H=-10000
05800	
05900	18	DO 7 I=2,KK
06000		IF(NE(I).NE.0)GO TO 7
06100	C  SKIP IF SAME LINE.
06200		IF(MISS(I,RK,Q))GO TO 7
06400	C  TRY NEXT POINT IF IT HIT A -1 LINE.
07000	9	B=HGHT(I,RK,Q,R)
07100		IF(B.GT.Y)GO TO 7
07200		IF(B.LE.H)GO TO 7
07300		H=B
07310		IX=I
07500	C  FOUND HIGHEST NEW POINT
07600	7	CONTINUE
07700		IF(H.EQ.Y)GO TO 31
07800	C  WIPES OUT THIS LINE SEG.
08200		IF(H.NE.-10000)GO TO 31
08205		NX=-10000
08300	C***	X=1
08302		X=-1
08305		GO TO 6
08308	31	IF(IX.NE.JX.AND.X.GT.0)JA=3
08309		JX=IX
08311		CALL LINES(XK,H,JA)
08314		JA=2
08320		IF(X.GT.0)CALL LINES(XK,Y,JA)
08350		X=-X
08360	600	GO TO 6
08370		CALL DPYOUT(1)
08500	6	CONTINUE
08510	2	CONTINUE
08600	
12000		END
13000		
13100		FUNCTION HGHT(J,A,Q,R)
13110		DIMENSION Q(1),R(1)
13120		B=R(J-1)
13130		D=Q(J-1)
13140		F=Q(J)
13200		HGHT=((R(J)-B)*(A-D))/(F-D)+B
13250		IF(F.EQ.D)HGHT=B
13300		END
13400	
14700		FUNCTION MISS(J,A,Q)
14800		DIMENSION Q(1)
14900		B=Q(J)
15000		C=Q(J-1)
15100		MISS=-1
15150		IF((A.LT.C.AND.A.GT.B).OR.(A.LT.B.AND.A.GT.C))MISS=0
16000		END
16100	C  MISS=-1, HIT=0
16200	
16300		FUNCTION HALF(A,J)
16400		DIMENSION A(1)
16500		HALF=(A(J-1)-A(J))/2.+A(J)
16600		END