C
C=============================================================================
C
C	MPASGD - ASSIGN MULPLT GRAPHICS DEVICE
C
C	ALL DEVICE SPECS. ARE STORED IN /GRPHDV/ COMMON AS ASCIZ STRINGS.
C
C=============================================================================
C
	BYTE DEFGDN(6),DEFGD0(32)
	DATA DEFGDN/'G','D','1',':',0,0/
	DATA DEFGD0/'S','Y','0',':','V','E','C','T','O','R',
	1			    '.','B','I','N',';','1',16*0/
C	SET SOME DEFAULTS FOR STARTUP
C
	JDEV = IDEV		! remember who we are talking to
	IDEV=-1
	ICMD=1			!ASSUME IT WILL BE A DISPLAY COMMAND
	IF(LSTRN0.LE.0)GO TO 40 ! yup - display all (it may be a G? command)
C
C	NON-NULL LINE, LOOK FOR FIRST NON-BLANK CHARACTER
C
10	DO 12 I=1,LSTRN0
	IF (STRNG0(I) .NE. "40) GO TO 20
12	CONTINUE
	GO TO 40		!GARBAGE LINE => NULL LINE
C
C	NOW SCAN FOR "=" FOR ASSIGNMENT
C
20	DO 22 J=I,LSTRN0
	IF (STRNG0(J) .EQ. "75) GO TO 30
22	CONTINUE
C
C	IF HERE, DEVICE # SPANS FROM I TO J; DEVICE SPEC STARTS AT J+1
C
30	K=J-I
	IF (K .LE.0 ) GO TO 35
	DECODE(K,33,STRNG0(I),ERR=990)IDEV
33	FORMAT(I5)
	IF (IDEV. LT. 0 .OR. IDEV .GT. MAXGD) GO TO 990
35	IF (J .LE. LSTRN0) ICMD=2	!RESET COMMAND TO ASSIGNMENT IF SAW "="
	K=LSTRN0-J
	IF (K .LE. 0) GO TO 40
	IF (IDEV .EQ. 0) GOTO 38
	IF (K .GT. 5) GO TO 994	!TRAP BAD DEVICE SPECS
	DO 37 I=J+1,LSTRN0
	IF (STRNG0(I) .NE. "72) GO TO 37
	STRNG0(I+1)=0		!FORCE NULL AFTER ":"
	GO TO 40
37	CONTINUE
	IF (IDEV .GT. 0) GOTO 994
38	STRNG0(LSTRN0+1) = 0
C
C	DISPATCH COMMAND
C
40	GO TO (100,200),ICMD
	GOTO 2000
C
C	DISPLAY CURRENT ASSIGNMENTS
C
100	IFIRST = 0
	ILAST = MAXGD
	IF (IDEV .LT. 0) GOTO 105
	IFIRST = IDEV
	ILAST = IDEV
C
105	DO 150 IDEV=IFIRST,ILAST
	IF (IDEV .GT. 0) GOTO 125
	DO 110 K=1,32
	IF (GDDEV0(K) .EQ. 0) GOTO 111
110	CONTINUE
111	K = K - 1
	WRITE (LUNTI,115) IDEV,(GDDEV0(L),L=1,K)
115	FORMAT(' Grpahics Device ',I2,' => ',32A1)
	GOTO 150
C
125	CALL VECTOR(X,Y,-5)			! ask vector if this device exists
	IF (X .LE. 0) GOTO 150			! no device here ...
	DO 129 K=1,6
	IF (GDDEVN(K,IDEV) .EQ. 0) GO TO 130	!FIND TRAILING NULL
129	CONTINUE
130	K=K-1
C
	WRITE (LUNTI,140) IDEV,(GDDEVN(L,IDEV),L=1,K)
140	FORMAT('$Graphics Device ',I2,' => ',6A1)
	CALL VECTOR(FLOAT(LUNTI),0.,6)		! tell us the type of device
150	CONTINUE
	GOTO 2000
C
C	(RE)ASSIGN RSX DEVICE TO GRAPHICS DEVICE
C	 DEVICE SPEC STARTS @ J+1, WITH LENGTH OF K CHARACTERS
C
200	IF (IDEV .LT. 0 .AND. K .GT. 0) GOTO 998	! trap "=DDnn:"
	IFIRST = 0			! assume we work on all devices
	ILAST = MAXGD
	IF (IDEV .LT. 0) GOTO 205
	IFIRST = IDEV
	ILAST = IDEV
C
205	IF (K .LE. 0) GO TO 250		!BRANCH IF SETTING DEFAULTS
	IF (IDEV .EQ. 0) GOTO 210
	DO 208 L=1,6
	GDDEVN(L,IDEV) = STRNG0(J+L)
208	CONTINUE
	GOTO 2000
C
210	DO 220 L=1,32
	GDDEV0(L) = STRNG0(J+L)
220	CONTINUE
	GOTO 2000
C
C	set the defaults (GTidev:)
C
250	DO 300 IDEV=IFIRST,ILAST
	IF (IDEV .EQ. 0) GOTO 280
C
	DO 270 L = 1,6
	GDDEVN(L,IDEV) = DEFGDN(L)
270	CONTINUE
	GDDEVN(3,IDEV) = "60+IDEV	! ASCII for IDEV
	GOTO 300
C
280	DO 290 L=1,32
	GDDEV0(L) = DEFGD0(L)
290	CONTINUE
300	CONTINUE
	GOTO 2000
C
C	ERROR MESSAGES
C
990	WRITE(LUNTI,991)
991	FORMAT('0MPASGD: Invalid graphics device')
	GO TO 1000
994	WRITE(LUNTI,995)
995	FORMAT('0MPASGD: Invalid RSX device specification')
	GO TO 1000
998	WRITE(LUNTI,999)
999	FORMAT('0MPASGD: Illegal command')
1000	WRITE(LUNTI,1001)(STRNG0(I),I=1,LSTRN0)
1001	FORMAT(' ?-> ',82A1)
2000	IDEV = JDEV
	RETURN
	END