more readable API

Author: facontidavide

examples/crossdoor_example.cpp

@@ -58,22 +58,22 @@ int main()
 
     // Important: when the object tree goes out of scope, all the TreeNodes are destroyed
     auto tree = buildTreeFromText(factory, xml_text, blackboard);
-    TreeNode* root_node = tree.first.get();
 
-    StdCoutLogger logger_cout(root_node);
-    MinitraceLogger logger_minitrace(root_node, "bt_trace.json");
-    FileLogger logger_file(root_node, "bt_trace.fbl", 32);
+    StdCoutLogger logger_cout(tree.root_node);
+    MinitraceLogger logger_minitrace(tree.root_node, "bt_trace.json");
+    FileLogger logger_file(tree.root_node, "bt_trace.fbl", 32);
 #ifdef ZMQ_FOUND
-    PublisherZMQ publisher_zmq(root_node);
+    PublisherZMQ publisher_zmq(tree.root_node);
 #endif
 
-    std::cout << writeXML( factory, root_node, false ) << std::endl;
+    std::cout << writeXML( factory, tree.root_node, false ) << std::endl;
     std::cout << "---------------" << std::endl;
 
     // Keep on ticking until you get either a SUCCESS or FAILURE state
-    while( root_node->executeTick() == BT::NodeStatus::RUNNING)
+    NodeStatus status = NodeStatus::RUNNING;
+    while( status == NodeStatus::RUNNING )
     {
-        // continue;
+        status = tree.root_node->executeTick();
     }
     return 0;
 }

examples/tutorial_blackboard.cpp

@@ -96,13 +96,12 @@ int main()
     auto blackboard = Blackboard::create<BlackboardLocal>();
 
     // Important: when the object tree goes out of scope, all the TreeNodes are destroyed
-    auto res = buildTreeFromText(factory, xml_text, blackboard);
-    const TreeNode::Ptr& root_node = res.first;
+    auto tree = buildTreeFromText(factory, xml_text, blackboard);
 
     NodeStatus status = NodeStatus::RUNNING;
     while( status == NodeStatus::RUNNING )
     {
-        status = root_node->executeTick();
+        status = tree.root_node->executeTick();
     }
 
     return 0;

examples/tutorial_factory_tree.cpp

@@ -35,12 +35,11 @@ int main()
 
     // IMPORTANT: when the object tree goes out of scope, all the TreeNodes are destroyed
     auto tree = buildTreeFromText(factory, xml_text);
-    const TreeNode::Ptr& root_node = tree.first;
 
     // The tick is propagated to all the children.
     // until one of the returns FAILURE or RUNNING.
     // In this case all of the return SUCCESS
-    root_node->executeTick();
+    tree.root_node->executeTick();
 
     return 0;
 }

examples/tutorial_sequence_star.cpp

@@ -66,33 +66,32 @@ int main()
         std::cout << "\n------------ BUILDING A NEW TREE ------------\n\n" << std::endl;
 
         auto tree = buildTreeFromText(factory, xml_text);
-        TreeNode::Ptr root_node = tree.first;
 
         // This logger will show all the state transitions on console
-        StdCoutLogger logger_cout(root_node.get());
+        StdCoutLogger logger_cout(tree.root_node);
 
         // This other logger will save the state transition in a custom file format
         // simple_trace.fbl can be visualized using the command line tool [bt_log_cat]
-        FileLogger file_file(root_node.get(), "simple_trace.fbl", 32);
+        FileLogger file_file(tree.root_node, "simple_trace.fbl", 32);
 
         NodeStatus status;
 
         std::cout << "\n------- First executeTick() --------" << std::endl;
-        status = root_node->executeTick();
+        status = tree.root_node->executeTick();
         Assert( status == NodeStatus::RUNNING);
 
         std::cout << "\n------- sleep --------" << std::endl;
         std::this_thread::sleep_for(std::chrono::milliseconds(100));
 
         std::cout << "\n------- Second executeTick() --------" << std::endl;
-        status = root_node->executeTick();
+        status = tree.root_node->executeTick();
         Assert( status == NodeStatus::RUNNING);
 
         std::cout << "\n------- sleep --------" << std::endl;
         std::this_thread::sleep_for(std::chrono::milliseconds(100));
 
         std::cout << "\n------- Third executeTick() --------" << std::endl;
-        status = root_node->executeTick();
+        status = tree.root_node->executeTick();
         Assert( status == NodeStatus::SUCCESS);
 
         std::cout << std::endl;

include/behavior_tree_core/xml_parsing.h

@@ -35,17 +35,22 @@ class XMLParser
     const BehaviorTreeFactory& factory_;
 };
 
+struct Tree
+{
+   TreeNode* root_node;
+   std::vector<TreeNode::Ptr> nodes;
+};
+
 /** Helper function to do the most common steps all at once:
 * 1) Create an instance of XMLParse and call loadFromText.
 * 2) Instantiate the entire tree.
 * 3) Assign the given Blackboard
 *
 * return: a pair containing the root node (first) and a vector with all the instantiated nodes (second).
 */
-std::pair<TreeNode::Ptr, std::vector<TreeNode::Ptr>>
-buildTreeFromText(const BehaviorTreeFactory& factory,
-                  const std::string& text,
-                  const Blackboard::Ptr& blackboard = Blackboard::Ptr() );
+Tree buildTreeFromText(const BehaviorTreeFactory& factory,
+                       const std::string& text,
+                       const Blackboard::Ptr& blackboard = Blackboard::Ptr() );
 
 /** Helper function to do the most common steps all at once:
 * 1) Create an instance of XMLParse and call loadFromFile.
@@ -54,10 +59,9 @@ buildTreeFromText(const BehaviorTreeFactory& factory,
 *
 * return: a pair containing the root node (first) and a vector with all the instantiated nodes (second).
 */
-std::pair<TreeNode::Ptr, std::vector<TreeNode::Ptr>>
-buildTreeFromFile(const BehaviorTreeFactory& factory,
-                  const std::string& filename,
-                  const Blackboard::Ptr& blackboard = Blackboard::Ptr() );
+Tree buildTreeFromFile(const BehaviorTreeFactory& factory,
+                       const std::string& filename,
+                       const Blackboard::Ptr& blackboard = Blackboard::Ptr() );
 
 std::string writeXML(const BehaviorTreeFactory& factory,
                      const TreeNode* root_node,

src/xml_parsing.cpp

@@ -483,8 +483,7 @@ std::string writeXML(const BehaviorTreeFactory& factory,
     return std::string( printer.CStr(), printer.CStrSize()-1 );
 }
 
-std::pair<TreeNode::Ptr, std::vector<TreeNode::Ptr> >
-buildTreeFromText(const BehaviorTreeFactory &factory,
+Tree buildTreeFromText(const BehaviorTreeFactory &factory,
                   const std::string &text,
                   const Blackboard::Ptr &blackboard)
 {
@@ -494,11 +493,10 @@ buildTreeFromText(const BehaviorTreeFactory &factory,
     std::vector<TreeNode::Ptr> nodes;
     auto root = parser.instantiateTree(nodes);
     assignBlackboardToEntireTree(root.get(), blackboard );
-    return {root, nodes};
+    return {root.get(), nodes};
 }
 
-std::pair<TreeNode::Ptr, std::vector<TreeNode::Ptr> >
-buildTreeFromFile(const BehaviorTreeFactory &factory,
+Tree buildTreeFromFile(const BehaviorTreeFactory &factory,
                   const std::string &filename,
                   const Blackboard::Ptr &blackboard)
 {
@@ -508,7 +506,7 @@ buildTreeFromFile(const BehaviorTreeFactory &factory,
     std::vector<TreeNode::Ptr> nodes;
     auto root = parser.instantiateTree(nodes);
     assignBlackboardToEntireTree(root.get(), blackboard );
-    return {root, nodes};
+    return {root.get(), nodes};
 }
 
 }