C                  INTERNATIONAL AVS CENTER
C        (This disclaimer must remain at the top of all files)
C
C WARRANTY DISCLAIMER
C
C This module and the files associated with it are distributed free of charge.
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C directory located at the International AVS Center ftp site and to include
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C that site.
C
C The International AVS Center, MCNC, the AVS Consortium and the individual
C submitting the module and files associated with said module provide absolutely
C NO WARRANTY OF ANY KIND with respect to this software.  The entire risk as to
C the quality and performance of this software is with the user.  IN NO EVENT
C WILL The International AVS Center, MCNC, the AVS Consortium and the individual
C submitting the module and files associated with said module BE LIABLE TO
C ANYONE FOR ANY DAMAGES ARISING FROM THE USE OF THIS SOFTWARE, INCLUDING,
C WITHOUT LIMITATION, DAMAGES RESULTING FROM LOST DATA OR LOST PROFITS, OR ANY
C SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
C
C This AVS module and associated files are public domain software unless
C otherwise noted.  Permission is hereby granted to do whatever you like with
C it, subject to the conditions that may exist in copyrighted materials. Should
C you wish to make a contribution toward the improvement, modification, or
C general performance of this module, please send us your comments:  why you
C liked or disliked it, how you use it, and most important, how it helps your
C work. We will receive your comments at avs@ncsc.org.
C
C Please send AVS module bug reports to avs@ncsc.org.
C
C Author:  "insert name" (if users state on release form that they wish to
C remain anonymous, a control number will be placed at this location)
C Modifications:  Who modified, date modified ( so donor does not receive blame
C if modifications made and passed on to others do not work as described)
c pointsample.f: print (numerically) the value at a point in a field.
c ====================================================================== 
c
c Created by:   Ian Curington
c               Stardent Computer Limited
c               15 Frederick Sanger Road
c               The Surrey Research Park
c               Guildford
c               Surrey    GU2 5YD
c               United Kingdom
c               +44-483-505388
c               email: ianc@Stardent.COM
c
c Modified:   18 January 90 ianc: modification of avsplot
c             30 January 90 ianc: removed extra messages
c
c ====================================================================== 
C === avs module initialization, connection prototypes
      subroutine AVSinit_modules
      integer  iport
      integer  point_compute
      external point_compute
      external AVScreate_input_port
      integer  AVScreate_input_port
      integer iparam

C Set the module name and type
      call AVSset_module_name('point sample', 'renderer')

C Create an input port for the required field input
      iport = AVScreate_input_port('input field',
     $     'field 2D scalar uniform float', REQUIRED)

C Get several control dials
      iparam=AVSadd_parameter(' X Position','integer', 1, 1, 999)
      iparam=AVSadd_parameter(' Y Position','integer', 1, 1, 999)

C Tell AVS what function to call to do the compute
      call AVSset_compute_proc(point_compute)
      
      return
      end

C === avs compute module, process incomming data

      integer function point_compute(f,nx,ny,
     &                 islicex,islicey)
      integer nx, ny, nz
      real  f(nx, ny)
      integer islicex,islicey
      real value

      if ( islicex .le. 1 ) islicex = 1
      if ( islicey .le. 1 ) islicey = 1
      if ( islicex .gt. nx ) islicex = nx
      if ( islicey .gt. ny ) islicey = ny

      value  = f (islicex, islicey)

      write (*,*) ' pointsample: x= '
     &            ,islicex,' y= ',islicey,' value= ',value 
      
C When we're done, we return 1 to indicate success
      point_compute = 1
      return
      end