fix

examples/t12_groot_howto.cpp

@@ -10,18 +10,16 @@
  *  But this time we also show how to connect
  */
 
-// A custom structuree that I want to visualize in Groot2
+// A custom struct  that I want to visualize in Groot2
 struct Position2D {
   double x;
   double y;
 };
 
-// Allows Position2D to be visualized in Groot2
-// You still need BT::RegisterJsonDefinition<Position2D>(PositionToJson)
-void PositionToJson(nlohmann::json& j, const Position2D& p)
+BT_JSON_CONVERTER(Position2D, pos)
 {
-  j["x"] = p.x;
-  j["y"] = p.y;
+  add_field("x", &pos.x);
+  add_field("y", &pos.y);
 }
 
 // Simple Action that updates an instance of Position2D in the blackboard
@@ -97,7 +95,7 @@ int main()
   factory.registerBehaviorTreeFromText(xml_text);
 
   // Add this to allow Groot2 to visualize your custom type
-  BT::RegisterJsonDefinition<Position2D>(PositionToJson);
+  BT::RegisterJsonDefinition<Position2D>();
 
   auto tree = factory.createTree("MainTree");
 

include/behaviortree_cpp/json_export.h

@@ -9,7 +9,7 @@
 namespace BT {
 
 /**
-*  To add new type, you must follow these isntructions:
+*  To add new type to the JSON library, you should follow these isntructions:
 *    https://json.nlohmann.me/features/arbitrary_types/
 *
 *  Considering for instance the type:
@@ -24,19 +24,18 @@ namespace BT {
 *   void to_json(nlohmann::json& j, const Point2D& point);
 *   void from_json(const nlohmann::json& j, Point2D& point);
 *
-*  To avoir repeating yourself, we provide the macro BT_JSON_CONVERTION
-*  that implements both those function, at once.
-*  Usage:
+*  To avoid repeating yourself, we provide the macro BT_JSON_CONVERTION
+*  that implements both those function, at once. Usage:
 *
 *  BT_JSON_CONVERTER(Point2D, point)
 *  {
 *     add_field("x", &point.x);
 *     add_field("y", &point.y);
 *  }
 *
-*  Later, you MUST register the type in main using:
+*  Later, you MUST register the type using:
 *
-*   RegisterJsonDefinition<Point2D>();
+*  BT::RegisterJsonDefinition<Point2D>();
 */
 
 //-----------------------------------------------------------------------------------