[Paraview] Clean Ensight C binary format with Fortran 2003

[Christophe Peyret]

With Fortran 2003, it is now possible to write generic C binary files.


To illustrate, I join 2 files for those who would be interested into  
writing binary ensight directly from fortran. In the exemple it is is  
'BIG_ENDIAN' but you can also choose 'LITTLE_ENDEAN' .



   subroutine EnsightCase(FileOut,nf)
     !------------------------------------------------------
     !
     !  EnsightCase helps to write a Ensight's case file
     !
     !------------------------------------------------------
     implicit none

     character(50) :: FileOut
     integer       :: icase
     integer       :: i,nf
     !------------------------------------------------------

     write(*,'(/a)') ' Creating case file for Ensight and Paraview...'
     write(*,'(2a)')'File: ',trim(FileOut)//'.case'

     icase = 35
     open(icase,file=trim(FileOut)//'.case')

     !    Writing header file
     write(icase,'(a)')'FORMAT'
     write(icase,'(a/)')'type: ensight gold'

     write(icase,'(a)')'GEOMETRY'
     write(icase,'(a,a,a/)')'model: ',trim(FileOut),'.geom'


   !  write(icase,'(a)')'VARIABLE'
   !  if( nf/=1 )then
   !    write(icase,'(3a)')'scalar per node:           pressure       
',trim(FileOut),'_pres_0000.scl'
   !    write(icase,'(3a)')'scalar per node:           pressure       
',trim(FileOut),'_vel_0000.vec'
   !  else
   !    write(icase,'(3a)')'scalar per node:           pressure       
',trim(FileOut),'_pres_0***.scl'
   !    write(icase,'(3a)')'scalar per node:           pressure       
',trim(FileOut),'_vel_0***.vec'
   !
   !    write(icase,'(/a)')'TIME'
   !    write(icase,'( a)')'time set: 1'
   !    write(icase,'(a,i6)')'number of steps:',nf
   !    write(icase,'(f5.2)') (real(i,kind=4),i=0,nf-1)
   !  endif

     close(icase)

   end subroutine EnsightCase




   subroutine m_ensight_WriteEnsightMeshBIN(FileOut, vertices, tetra,  
trian, edges)
     !------------------------------------------------------
     use,intrinsic :: ISO_C_BINDING
     !------------------------------------------------------
     !
     ! WriteEnsightMeshBIN writes mesh data in Ensight's binary format
     !
     !------------------------------------------------------
     implicit none
     character(50)    , intent(in) :: FileOut
     real(c_float)    , intent(in) :: vertices(:,:)
     integer(c_int)   , optional   :: tetra   (:,:)
     integer(c_int)   , optional   :: trian   (:,:)
     integer(c_int)   , optional   :: edges   (:,:)
     !------------------------------------------------------
     integer(4)                :: geo  =0
     integer(4)                :: nVert=0
     integer(4)                :: nT4  =0
     integer(4)                :: nT3  =0
     integer(4)                :: nL2  =0
     !

     character(80)             :: cbuffer
     character(80)             :: header(5)                ! EnSight  
Gold character const buffer
     character(80) , parameter :: vert      ='coordinates' ! EnSight  
Gold character const buffer
     character(80) , parameter :: part      ='part'
     character(80) , parameter :: tetrahedra='tetra4'
     character(80) , parameter :: triangles ='tria3'
     character(80)             :: id_part(10)
     integer(4)                ::   ipart(10)

     integer(4)                :: i,ierr
     integer(4)                :: reclength
     integer(4)   , parameter  :: iens=11
     !------------------------------------------------------
     geo  =size(vertices,1)
     nVert=size(vertices,2)
     if( present(tetra) )nT4= size(tetra,2)
     if( present(trian) )nT3= size(trian,2)
     if( present(edges) )nL2= size(edges,2)


     write(*,'(3a)')'Writing Binary Format File: ',trim 
(FileOut)//'.geom'
     write(*,*)'Number of Vertices:  ',nVert
     write(*,*)'Number of Tetrahedra:',nT4
     write(*,*)'Number of Triangles: ',nT3
     write(*,*)'Number of Edges:     ',nL2
     !
     !     Header
     !
     header(1) = 'C Binary'
     header(2) = 'Ensight Binary Model Geometry'
     header(3) = 'File Created with WriteEnsightMeshBIN'
     header(4) = 'node id given'
     header(5) = 'element id given'
     !
     !   nodal coordinates
     !
     ipart  (1)=1
     id_part(1)= 'Volume'

     open (unit=iens,file=trim(FileOut)//'.geom',&
     &     form='unformatted'                   ,&
     &     recordtype='stream'                  ,&
     &     action='write'                       ,&
     &     convert='BIG_ENDIAN'                 ,&
     &     access='sequential'                   )


     cbuffer = 'C Binary'                            ; write(iens)  
cbuffer
     cbuffer = 'Ensight Binary Model Geometry'       ; write(iens)  
cbuffer
     cbuffer = 'File Created by WriteEnsightMeshBIN' ; write(iens)  
cbuffer
     cbuffer = 'node id given'                       ; write(iens)  
cbuffer
     cbuffer = 'element id given'                    ; write(iens)  
cbuffer

     cbuffer = 'extents'                             ; write(iens)  
cbuffer
     write (iens)minval(vertices(1,:)),maxval(vertices(1,:)),&
     &           minval(vertices(2,:)),maxval(vertices(2,:)),&
     &           minval(vertices(3,:)),maxval(vertices(3,:))

     cbuffer = 'part'                                ; write(iens)  
cbuffer
     write(iens)int(1,kind=c_int)

     cbuffer = 'Volumes'                             ; write(iens)  
cbuffer
     cbuffer = 'coordinates'                         ; write(iens)  
cbuffer

     write(iens) nVert
     write(iens) (i,i=1,nVert)
     write(iens) (real(vertices(1,i),kind=4),i=1,nVert)
     write(iens) (real(vertices(2,i),kind=4),i=1,nVert)
     write(iens) (real(vertices(3,i),kind=4),i=1,nVert)

    cbuffer = 'tetra4'                              ; write(iens)  
cbuffer
    write(iens) nT4
    write(iens) (i, i=1,nT4)
    write(iens) (tetra(1:4,i) ,i=1,nT4)

    close(iens)


   end subroutine m_ensight_WriteEnsightMeshBIN