Add further documentation to ExtractorCallbacks

extractor/extractor_callbacks.cpp

@@ -47,7 +47,12 @@ ExtractorCallbacks::ExtractorCallbacks(ExtractionContainers &extraction_containe
 {
 }
 
-/** warning: caller needs to take care of synchronization! */
+/**
+ * Takes the node position from osmium and the filtered properties from the lua
+ * profile and saves them to external memory.
+ *
+ * warning: caller needs to take care of synchronization!
+ */
 void ExtractorCallbacks::ProcessNode(const osmium::Node &input_node,
                                      const ExtractionNode &result_node)
 {
@@ -73,11 +78,11 @@ void ExtractorCallbacks::ProcessRestriction(
     }
 }
 /**
- * This function takes the geometry contained in the ```input_way``` and the tags
+ * Takes the geometry contained in the ```input_way``` and the tags computed
- * computed by the lua profile inside ```parsed_way``` and computes all edge segments.
+ * by the lua profile inside ```parsed_way``` and computes all edge segments.
  *
- * Depending on the forward/backwards weights the edges are split into forward and backward
+ * Depending on the forward/backwards weights the edges are split into forward
- * edges.
+ * and backward edges.
  *
  * warning: caller needs to take care of synchronization!
  */

extractor/extractor_callbacks.hpp

@@ -43,6 +43,13 @@ class ExtractionContainers;
 struct InputRestrictionContainer;
 struct ExtractionNode;
 
+/**
+ * This class is uses by the extractor with the results of the
+ * osmium based parsing and the customization through the lua profile.
+ *
+ * It mediates between the multi-threaded extraction process and the external memory containers.
+ * Thus the synchronization is handled inside of the extractor.
+ */
 class ExtractorCallbacks
 {
   private: