add id and parent to pdal::Metadata

include/pdal/Metadata.hpp

@@ -227,6 +227,23 @@ class PDAL_DLL Metadata
     /// returns the attribute value for a given attribute key
     std::string getAttribute(std::string const& name) const;    
 
+/** @name Parent/child relationships
+*/
+    /// denotes the parent relationship of this instance to another 
+    /// with a given metadata::id
+    /// @param id the metadata::id of the parent dimension to this instance
+    inline void setParent( metadata::id const& id)
+    { 
+        m_parentDimensionID = id;
+    }
+
+    /// @return the metadata::id of the parent Metadata entry to this one.
+    inline metadata::id const& getParent( ) const
+    {
+        return m_parentDimensionID;
+    }
+
+
 /** @name private attributes
 */
 private:
@@ -236,6 +253,7 @@ class PDAL_DLL Metadata
     metadata::Type m_type;
     metadata::MetadataAttributeM m_attributes;
     metadata::id m_uuid;
+    metadata::id m_parentDimensionID;
 
 };
 

src/Metadata.cpp

@@ -41,6 +41,11 @@
 #include <sstream>
 #include <string>
 
+#include <boost/algorithm/string.hpp>
+#include <boost/uuid/string_generator.hpp>
+#include <boost/uuid/random_generator.hpp>
+#include <boost/uuid/uuid_io.hpp>
+
 namespace pdal
 {
 
@@ -49,6 +54,8 @@ Metadata::Metadata( std::string const& name,
     : m_name(name)
     , m_namespace(ns) 
     , m_type(metadata::String)
+    , m_uuid(boost::uuids::nil_uuid())
+    , m_parentDimensionID(boost::uuids::nil_uuid())
 {
     return;
 }
@@ -59,6 +66,8 @@ Metadata::Metadata(const Metadata& other)
     , m_name(other.m_name)
     , m_namespace(other.m_namespace)
     , m_type(other.m_type)
+    , m_uuid(other.m_uuid)
+    , m_parentDimensionID(other.m_parentDimensionID)
 {
     return;
 }