Remove more StringGrid usage

Signed-off-by: Dan Bailey <danbailey@ilm.com>

Author: danrbailey

doc/examplecode.txt

@@ -1199,7 +1199,6 @@ void processTypedGrid(openvdb::GridBase::Ptr grid, OpType& op)
     else if (grid->isType<openvdb::Vec3IGrid>())  CALL_OP(openvdb::Vec3IGrid);
     else if (grid->isType<openvdb::Vec3SGrid>())  CALL_OP(openvdb::Vec3SGrid);
     else if (grid->isType<openvdb::Vec3DGrid>())  CALL_OP(openvdb::Vec3DGrid);
-    else if (grid->isType<openvdb::StringGrid>()) CALL_OP(openvdb::StringGrid);
 
 #undef CALL_OP
 }
@@ -1221,11 +1220,6 @@ struct PruneOp {
     {
         grid->tree().prune(typename GridType::ValueType(tolerance));
     }
-    // Overload to handle string-valued grids
-    void operator()(openvdb::StringGrid::Ptr grid) const
-    {
-        grid->tree().prune();
-    }
 };
 
 // Read all grids from a file.

openvdb/openvdb/openvdb.cc

@@ -78,13 +78,6 @@ initialize()
     GridBase::clearRegistry();
     GridTypes::foreach<RegisterGrid>();
 
-    // @note String grids types are deprecated but we still register them
-    //   as supported serializable types for backward compatibility. This
-    //   will likely be removed in a future major version
-OPENVDB_NO_DEPRECATION_WARNING_BEGIN
-    StringGrid::registerGrid();
-OPENVDB_NO_DEPRECATION_WARNING_END
-
     // Register types associated with point index grids.
     Metadata::registerType(typeNameAsString<PointIndex32>(), Int32Metadata::createMetadata);
     Metadata::registerType(typeNameAsString<PointIndex64>(), Int64Metadata::createMetadata);