SUBROUTINE FACTOR(FACTR)
C
C	NAME:FACTOR
C
C	LANGUAGE:  FORTRAN
C
C	OPERATING SYSTEM:  DEC VAX/VMS
C
C	ORDER NUMBER:  5448-SE
C
C	PART NUMBER:  000-025522-001  OCTOBER 1985
C
C	PRODUCT:  DEC VAX/VMS VERSAPLOT COLOR RANDOM 2.0
C
C	VERSATEC, INC., SANTA CLARA, CALIFORNIA 95051
C	A XEROX COMPANY
C
C	Copyright (C) 1985 by Xerox Corporation.  All rights reserved.
C
C	"NOTICE. THIS PROGRAM IS THE EXCLUSIVE PROPERTY OF VERSATEC,
C	INC. AND IS ISSUED IN STRICT CONFIDENCE UNDER A PREARRANGED
C	LICENSE AGREEMENT AND IS NOT TO BE DISCLOSED IN ANY MANNER TO
C	PERSONS OUTSIDE THE LICENSED ORGANIZATION AND SHALL NOT BE
C	REPRODUCED OR DISSEMINATED, IN WHOLE OR PART, TO ANYONE OUTSIDE
C	THE LICENSED ORGANIZATION WITHOUT THE PRIOR WRITTEN APPROVAL OF
C	VERSATEC, INC. UNLESS OTHERWISE PROVIDED FOR BY SUCH LICENSE
C	AGREEMENT.  THIS WORK IS PROTECTED AS AN UNPUBLISHED WORK UNDER
C	THE COPYRIGHT ACT OF 1976."
C
C	REVISION HISTORY:
C
C	REV. C   8/22/85	IGNORE THE CALLS WITH THE RATIO OF ZERO
C				AND LESS, AND NOTIFY THE USER WITH A
C				MESSAGE.
C	FACTOR - SET DRAWING FACTOR
C
C	SUBROUTINE FACTOR ALLOWS THE PROGRAMMER TO ENLARGE OR REDUCE
C	THE CLIPPING WINDOW BY SPECIFYING THE RATIO OF THE DESIRED
C	WINDOW TO THE NORMAL CLIPPING WINDOW.
C
C	ENTRY: CALL FACTOR(FACTR)
C
C		 FACTR - RATIO OF DESIRED SIZE TO 'NORMAL' SIZE
C			(FOR EXAMPLE:
C			 =2.0 GIVES A DOUBLE SIZE PLOT,
C			 =0.5 GIVES A HALF SIZE PLOT.)
C			 THIS RATIO MUST BE GREATER THAN ZERO, OTHERWISE
C			 THE CALL WILL BE IGNORED AND A MESSAGE WILL NOTIFY
C			 THE USER.
C
C	EXIT: RETURN
C
C	CALLS: CWTV, MSGLG1
C
C	CALLED BY: USER
C
C	COMMON USED:
C	/DVCOM/
C		R FACT    - CURRENT SCALING FACTOR. USED BY *FACTOR*
C		R VCP()   - CURRENT POINT IN COMPUTATIONAL COORDINATES
C		R WIN()   - THE CURRENT VIEW WINDOW IN COMPUTATIONAL
C		            COORDINATES
C		R WX()    - ARRAY OF X ORDINATES FOR REPRESENTING THE
C		            VIEW WINDOW AS POLYGONS.
C		R WY()    - ARRAY OF Y ORDINATES FOR REPRESENTING THE
C		            VIEW WINDOW AS POLYGONS.
C
C	/MSGCOM/
C		R RELARG()- ARRAY FOR PASSING REAL OUTPUT ARGUMENTS
C
C
C
C
	INCLUDE 'DVCOM.CMN'
C
C
	INCLUDE 'MSGCOM.CMN'
C
C
C-D  DEBUG MESSAGE
C	 RELARG(1)=FACTR
C	 CALL MSGLG1(26)
C-D
C
C...	CHECK THE VALIDITY OF THE NEW FACTOR
C
	IF( FACTR. LE. 0 ) GO TO 20
C
C...	CORRECTION FACTOR COMPUTED FROM NEW FACTOR AND OLD FACTOR
	ALMT = FACT/FACTR
C
C...	ADJUST WINDOW FOR NEW FACTOR
	DO 10 I=1,4
	WIN(I) = WIN(I) * ALMT
	WX(I) = WX(I) * ALMT
	WY(I) = WY(I) * ALMT
   10	CONTINUE
C
C...	ADJUST REORIGIN POINT/CURRENT POSITION FOR NEW FACTOR
	DO 15 I=1,2
	RORG(I) = RORG(I)*ALMT
	VCP(I) = VCP(I)*ALMT
   15	CONTINUE
C
C...	ADJUST WTV TRANSFORMATION FOR NEW FACTOR
	CALL CWTV
C
C...	FACTOR SAVED
	FACT = FACTR
C
	RETURN
C
C...	INVALID FACTOR REQUEST, INFORM THE USER AND RETURN.
C
   20	RELARG( 1 ) = FACTR
	 CALL MSGLG1( 138 )
	RETURN
C
	END