Use grid_mapping attribute for GRID_PROJECTION.

src/cdf_write.c

@@ -567,8 +567,7 @@ int cdfDefVar(stream_t *streamptr, int varID)
         cdf_put_att_int(fileID, ncvarid, "table", NC_INT, 1, &tablenum);
     }
 
-  char coordinates[CDI_MAX_NAME];
-  coordinates[0] = 0;
+  char coordinates[CDI_MAX_NAME]; coordinates[0] = 0;
 
   if ( zaxis_is_scalar )
     {
@@ -589,33 +588,26 @@ int cdfDefVar(stream_t *streamptr, int varID)
         cdf_put_att_text(fileID, ncvarid, "grid_type", len, gridNamePtr(gridtype));
     }
 
-  if ( gridIsRotated(gridID) )
-    {
-      char mapping[] = "rotated_pole";
-      cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(mapping), mapping);
-    }
+  char gmapvarname[CDI_MAX_NAME]; gmapvarname[0] = 0;
 
-  if ( gridtype == GRID_PROJECTION )
-    {
-      char mapping[] = "dummy";
-      cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(mapping), mapping);
-    }
-  else if ( gridtype == GRID_SINUSOIDAL )
-    {
-      char mapping[] = "sinusoidal";
-      cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(mapping), mapping);
-    }
-  else if ( gridtype == GRID_LAEA )
-    {
-      char mapping[] = "laea";
-      cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(mapping), mapping);
-    }
-  else if ( gridtype == GRID_LCC2 )
+  if      ( gridtype == GRID_SINUSOIDAL ) strcpy(gmapvarname, "sinusoidal");
+  else if ( gridtype == GRID_LAEA )       strcpy(gmapvarname, "laea");
+  else if ( gridtype == GRID_LCC2 )       strcpy(gmapvarname, "Lambert_Conformal");
+  else if ( gridtype == GRID_LONLAT && gridIsRotated(gridID) ) strcpy(gmapvarname, "rotated_pole");
+  else
     {
-      char mapping[] = "Lambert_Conformal";
-      cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(mapping), mapping);
+      char mapping[CDI_MAX_NAME]; mapping[0] = 0;
+      cdiGridInqKeyStr(gridID, CDI_KEY_MAPPING, CDI_MAX_NAME, mapping);
+      if ( mapping[0] )
+        {
+          cdiGridInqKeyStr(gridID, CDI_KEY_MAPNAME, CDI_MAX_NAME, gmapvarname);
+          if ( !gmapvarname[0] ) strcpy(gmapvarname, "dummy");
+        }
     }
-  else if ( gridtype == GRID_TRAJECTORY )
+
+  if ( gmapvarname[0] ) cdf_put_att_text(fileID, ncvarid, "grid_mapping", strlen(gmapvarname), gmapvarname);
+
+  if ( gridtype == GRID_TRAJECTORY )
     {
       cdf_put_att_text(fileID, ncvarid, "coordinates", 9, "tlon tlat" );
     }
@@ -1286,3 +1278,13 @@ void cdf_write_record(stream_t *streamptr, int memtype, const void *data, int nm
 }
 
 #endif
+
+/*
+ * Local Variables:
+ * c-file-style: "Java"
+ * c-basic-offset: 2
+ * indent-tabs-mode: nil
+ * show-trailing-whitespace: t
+ * require-trailing-newline: t
+ * End:
+ */

src/stream_cdf_i.c

@@ -2271,8 +2271,8 @@ bool cdf_read_coordinates(struct cdfLazyGrid *restrict lazyGrid, ncvar_t *ncvar,
       int gmapvarid = ncvar->gmapid;
       if ( gmapvarid != UNDEFID && cdfCheckAttText(ncvar->ncid, gmapvarid, "grid_mapping_name") )
         {
-          enum {attstringlen = 256}; char attstring[attstringlen];
-          cdfGetAttText(ncvar->ncid, gmapvarid, "grid_mapping_name", attstringlen, attstring);
+          char attstring[CDI_MAX_NAME];
+          cdfGetAttText(ncvar->ncid, gmapvarid, "grid_mapping_name", CDI_MAX_NAME, attstring);
           if ( strcmp(attstring, "latitude_longitude") == 0 ) gridtype = ncvar->gridtype;
         }
     }
@@ -2435,8 +2435,8 @@ void cdf_read_mapping_atts(int ncid, int gmapvarid, int projID, const char *varn
 {
   if ( cdfCheckAttText(ncid, gmapvarid, "grid_mapping_name") )
     {
-      enum {attstringlen = 256}; char attstring[attstringlen];
-      cdfGetAttText(ncid, gmapvarid, "grid_mapping_name", attstringlen, attstring);
+      char attstring[CDI_MAX_NAME];
+      cdfGetAttText(ncid, gmapvarid, "grid_mapping_name", CDI_MAX_NAME, attstring);
       cdiGridDefKeyStr(projID, CDI_KEY_MAPPING, (int)(strlen(attstring)+1), attstring);
     }
   else

src/stream_cdf_o.c

@@ -1969,18 +1969,24 @@ void cdfDefPole(stream_t *streamptr, int gridID)
 static
 void cdf_def_mapping(stream_t *streamptr, int gridID)
 {
-  int fileID = streamptr->fileID;
-
-  static const char varname[] = "dummy";
+  char mapping[CDI_MAX_NAME]; mapping[0] = 0;
+  cdiGridInqKeyStr(gridID, CDI_KEY_MAPPING, CDI_MAX_NAME, mapping);
+  if ( mapping[0] )
+    {
+      char gmapvarname[CDI_MAX_NAME]; gmapvarname[0] = 0;
+      cdiGridInqKeyStr(gridID, CDI_KEY_MAPNAME, CDI_MAX_NAME, gmapvarname);
+      if ( !gmapvarname[0] ) strcpy(gmapvarname, "dummy");
 
-  cdf_redef(fileID);
+      int fileID = streamptr->fileID;
+      cdf_redef(fileID);
 
-  int ncvarid;
-  int ncerrcode = nc_def_var(fileID, varname, (nc_type) NC_CHAR, 0, NULL, &ncvarid);
-  if ( ncerrcode == NC_NOERR )
-    cdfDefineAttributes(gridID, CDI_GLOBAL, fileID, ncvarid);
+      int ncvarid;
+      int ncerrcode = nc_def_var(fileID, gmapvarname, (nc_type) NC_CHAR, 0, NULL, &ncvarid);
+      if ( ncerrcode == NC_NOERR )
+        cdfDefineAttributes(gridID, CDI_GLOBAL, fileID, ncvarid);
 
-  cdf_enddef(fileID);
+      cdf_enddef(fileID);
+    }
 }
 
 static
@@ -2116,7 +2122,7 @@ void cdfDefGrid(stream_t *streamptr, int gridID)
           if ( gridInqXsize(gridID) > 0 ) cdfDefXaxis(streamptr, gridID, ndims);
           if ( gridInqYsize(gridID) > 0 ) cdfDefYaxis(streamptr, gridID, ndims);
 
-          if ( gridtype == GRID_PROJECTION ) cdf_def_mapping(streamptr, gridID);
+          cdf_def_mapping(streamptr, gridID);
         }
 
       if ( gridIsRotated(gridID) ) cdfDefPole(streamptr, gridID);
@@ -2210,6 +2216,7 @@ void cdfDefVars(stream_t *streamptr)
 }
 
 #endif
+
 /*
  * Local Variables:
  * c-file-style: "Java"