C++*********************************************************************
C
C TRAFC3.F
C                  OPFILEC                         FEB  03 ARDEAN LEITH
C
C **********************************************************************
C=* FROM: SPIDER - MODULAR IMAGE PROCESSING SYSTEM.   AUTHOR: J.FRANK  *
C=* Copyright (C) 1985-2005  Health Research Inc.                      *
C=*                                                                    *
C=* HEALTH RESEARCH INCORPORATED (HRI),                                *   
C=* ONE UNIVERSITY PLACE, RENSSELAER, NY 12144-3455.                   *
C=*                                                                    *
C=* Email:  spider@wadsworth.org                                       *
C=*                                                                    *
C=* This program is free software; you can redistribute it and/or      *
C=* modify it under the terms of the GNU General Public License as     *
C=* published by the Free Software Foundation; either version 2 of the *
C=* License, or (at your option) any later version.                    *
C=*                                                                    *
C=* This program is distributed in the hope that it will be useful,    *
C=* but WITHOUT ANY WARRANTY; without even the implied warranty of     *
C=* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  *
C=* General Public License for more details.                           *
C=*                                                                    *
C=* You should have received a copy of the GNU General Public License  *
C=* along with this program; if not, write to the                      *
C=* Free Software Foundation, Inc.,                                    *
C=* 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.      *
C=*                                                                    *
C **********************************************************************
C
C
C changed 9/5/94 to include complete sign reversal and intelligible
C Gaussian parameter jf
C  FIXED, PP 3/2/95
C
C23456789012345678901234567890123456789012345678901234567890123456789012
C--*********************************************************************

         SUBROUTINE TRAFC3(LUN)

         INCLUDE 'CMBLOCK.INC'
         COMMON        B(1)
	 COMPLEX       B
         CHARACTER *81 FILNAM
         REAL          LAMBDA,KM,SIGN
         CHARACTER     NULL

         DATA PI/3.1415926/

         NULL = CHAR(0)

         CALL FILERD(FILNAM,NLET,NULL,'OUTPUT',IRTFLG)
         IF (IRTFLG .EQ. -1) RETURN

         CALL RDPRM(CS,NOT_USED,'CS(MM)')
         CALL RDPRM2(DZ,LAMBDA,NOT_USED,
     &       'DEFOCUS(ANGSTROEMS), LAMBDA(ANGSTROEMS)')
         CALL RDPRMI(NSAM,NDUM,NOT_USED,'NUMBER OF SP.FREQ.PTS')
         CALL RDPRM(KM,NOT_USED,'MAXIMUM SPATIAL FREQUENCY[A-1]')
         CALL RDPRM2(Q,DS,NOT_USED,
     &       'SOURCE SIZE[A-1], DEFOCUS SPREAD[A]')
         CALL RDPRM2(DZA,AZZ,NOT_USED,'ASTIGMATISM[A], AZIMUTH[DEG]')
         CALL RDPRM2(WGH,ENV,NOT_USED,
     &      'AMPL CONTRAST RATIO [0-1], GAUSSIAN ENV HALFW [FOU UNITS]')
         ENV=1./ENV**2
         CALL  RDPRM(SIGN,NOT_USED,'SIGN (+1 OR -1.)')
         IFORM = -7
         NROW=NSAM
         NSLICE=NROW
	 IF (MOD(NSAM,2).EQ.0)  THEN
            IFORM = -22
	    LSM=NSAM+2
	 ELSE
	    IFORM=-21
	    LSM=NSAM+1
	 ENDIF

         MAXIM = 0
         CALL OPFILEC(0,.FALSE.,FILNAM,LUN,'U',IFORM,LSM,NROW,NSLICE,
     &               MAXIM,' ',.FALSE.,IRTFLG)
         IF (IRTFLG .NE. 0) RETURN

         SC=KM/FLOAT(NSAM/2)

C        IE=0 SELECTS TRANSFER FUNCTION OPTION IN SUBROUTINE TFD
	 IE=0
	 WGH = ATAN(WGH/(1.0-WGH))
	 CS = CS*1.E7

         NS2=NSAM/2
         NR2=NROW/2
         NL2=NSLICE/2
C
	DO K=1,NSLICE
	   IZ=K-1
	   IF (IZ.GT.NL2)  IZ=IZ-NSLICE
	   DO J=1,NROW
	      IY=J-1
	      IF(IY.GT.NR2)  IY=IY-NROW
	      DO I=1,LSM
	         IX=(I-1)/2
C
                 AK = SQRT(FLOAT(IX*IX)+FLOAT(IY*IY)+FLOAT(IZ*IZ))*SC
                 IF (AK.NE.0.0) THEN
                    AZ=0.0
                 ELSE
                    AZ = PI/2.
                 ENDIF
C                AZ=ATAN2(0.0,AK)
                 AZR=AZZ*(PI/180.)
                 DZZ=DZ+DZA/2*SIN(2*(AZ-AZR))
                 CALL TFD(TF,CS,DZZ,LAMBDA,Q,DS,IE,AK,WGH,ENV)
                        B(IX+1)=CMPLX(TF*SIGN,0.0)
              ENDDO
              CALL WRTLIN(LUN,B,LSM,J+(K-1)*NROW)
           ENDDO
	 ENDDO
         END