Start implemented Zernike FE filter

CMakeLists.txt

@@ -430,6 +430,7 @@ set(LIBOPENMC_FORTRAN_SRC
   src/tallies/tally_filter_sptl_legendre.F90
   src/tallies/tally_filter_surface.F90
   src/tallies/tally_filter_universe.F90
+  src/tallies/tally_filter_zernike.F90
   src/tallies/tally_header.F90
   src/tallies/trigger.F90
   src/tallies/trigger_header.F90

src/constants.F90

@@ -358,7 +358,7 @@ module constants
   integer, parameter :: NO_BIN_FOUND = -1
 
   ! Tally filter and map types
-  integer, parameter :: N_FILTER_TYPES = 19
+  integer, parameter :: N_FILTER_TYPES = 20
   integer, parameter :: &
        FILTER_UNIVERSE       = 1,  &
        FILTER_MATERIAL       = 2,  &
@@ -378,7 +378,8 @@ module constants
        FILTER_MESHSURFACE    = 16, &
        FILTER_LEGENDRE       = 17, &
        FILTER_SPH_HARMONICS  = 18, &
-       FILTER_SPTL_LEGENDRE  = 19
+       FILTER_SPTL_LEGENDRE  = 19, &
+       FILTER_ZERNIKE        = 20
 
   ! Mesh types
   integer, parameter :: &

src/tallies/tally_filter.F90

@@ -27,6 +27,7 @@ module tally_filter
   use tally_filter_sptl_legendre
   use tally_filter_surface
   use tally_filter_universe
+  use tally_filter_zernike
 
   implicit none
 
@@ -87,6 +88,8 @@ contains
           type_ = 'surface'
         type is (UniverseFilter)
           type_ = 'universe'
+        type is (ZernikeFilter)
+          type_ = 'zernike'
         end select
 
         ! Convert Fortran string to null-terminated C string. We assume the
@@ -164,6 +167,8 @@ contains
           allocate(SurfaceFilter :: filters(index) % obj)
         case ('universe')
           allocate(UniverseFilter :: filters(index) % obj)
+        case ('zernike')
+          allocate(ZernikeFilter :: filters(index) % obj)
         case default
           err = E_UNASSIGNED
           call set_errmsg("Unknown filter type: " // trim(type_))

src/tallies/tally_header.F90

@@ -362,6 +362,9 @@ contains
       type is (SpatialLegendreFilter)
         j = FILTER_SPTL_LEGENDRE
         this % estimator = ESTIMATOR_COLLISION
+      type is (ZernikeFilter)
+        j = FILTER_ZERNIKE
+        this % estimator = ESTIMATOR_COLLISION
       end select
       this % find_filter(j) = i
     end do