SUBROUTINE PLTOV(F1,F2,NP,NT,S,O,PL)
C	[OUTER VIEW]
C	PROGRAMM TO PRODUCE A PERSPECTIVE DRAWING OF A SINGLE VALUED
C	FUNCTION DEFINED OVER A SPHERICAL SURFACE, IN SUCH A WAY AS
C	TO EXHIBIT THE ARCS OF LATITUDE AND LONTITUDE.
C	F1(NP,NT) ARRAY OF VALUES OF FIRST FUNCTION
C	F2(NP,NT) ARRAY OF VALUES OF SECOND FUNCTION
C	NP	NUMBER (=2*N+1) OF POINTS OF LATITUDE
C	NT	NUMBER OF POINTS ON ONE LONGITUDE
C	S	S=1, OUTER; S=-1, INNER VIEW
C	O(3,3)	ORTHOGONAL ROTATION MATRIX
C	PL	PEN MOVEMENT SUBROUTINE
C	[02-JUN-74]
C	COPIED FROM DECUS
C	[STEIGER THD 20-DEC-75]
	EXTERNAL PL
	LOGICAL B,C
	DIMENSION F1(1),F2(1),O(3,3)
	COMMON/VIS/ N0
	CALL VISNP(PH,TH,JP,IT,NP,NT,O)
	NH=(NP-1)/2
	CALL VISSP(R,P,1.0,TH,PH+0.05,O)
	B=((-0.25).LT.P).AND.(P.LE.(0.25))
	C=.NOT.B
	IF(TH.GT.(1.57079)) GOTO 10
	I1=1
	I2=IT
	I3=IT
	I4=NT
	GOTO 12
10	I1=IT
	I2=NT
	I3=1
	I4=IT
12	J1=JP
	J2=JP+NH
	J3=JP-NH-1
	J4=JP
	N0=0
	CALL VISOS(F1,F2,J1,J2,NP,I1,I2,NT,1,-1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I1,I2,NT,1,1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I3,I4,NT,1,1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I3,I4,NT,1,-1,S,B,O,PL)
	N0=0
	CALL VISOS(F1,F2,J1,J2,NP,I1,I2,NT,-1,-1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I1,I2,NT,-1,1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I3,I4,NT,-1,1,S,B,O,PL)
	CALL VISOS(F1,F2,J1,J2,NP,I3,I4,NT,-1,-1,S,B,O,PL)
	RETURN
	END