t06_wrap_legacy.cpp
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4 
5 
11 // clang-format off
12 const std::string xml_text = R"(
13 
14  <root main_tree_to_execute = "MainTree" >
15  <BehaviorTree ID="MainTree">
16  <SequenceStar name="root">
17  <MoveTo goal="-1;3;0.5" />
18  <MoveTo goal="${myGoal}" />
19  </SequenceStar>
20  </BehaviorTree>
21  </root>
22  )";
23 
24 // clang-format on
25 
26 // This is my custom type.
27 // By default, we don't know how to read this from a NodeParameter.
28 struct Point3D { double x,y,z; };
29 
30 // We want to create an ActionNode that calls the method MyLegacyMoveTo::go
32 {
33 public:
34  bool go(Point3D goal)
35  {
36  printf("Going to: %f %f %f\n", goal.x, goal.y, goal.z);
37  return true; // true means success in my legacy code
38  }
39 };
40 
41 // Similarly to the previous tutorials, we need to implement this parsing method,
42 // providing a specialization of BT::convertFromString
43 namespace BT
44 {
45 template <> Point3D convertFromString(const StringView& key)
46 {
47  // three real numbers separated by semicolons
48  auto parts = BT::splitString(key, ';');
49  if (parts.size() != 3)
50  {
51  throw std::runtime_error("invalid input)");
52  }
53  else
54  {
55  Point3D output;
56  output.x = convertFromString<double>(parts[0]);
57  output.y = convertFromString<double>(parts[1]);
58  output.z = convertFromString<double>(parts[2]);
59  return output;
60  }
61 }
62 }
63 
64 
65 int main()
66 {
67  using namespace BT;
68 
69  MyLegacyMoveTo move_to;
70 
71  // Here we use a lambda that captures the reference of move_to
72  auto MoveToWrapperWithLambda = [&move_to](TreeNode& parent_node) -> NodeStatus
73  {
74  Point3D goal;
75  // thanks to paren_node, you can access easily the NodeParameters and the blackboard
76  parent_node.getParam("goal", goal);
77 
78  // you can write and read the blackboard if you like
79  //parent_node.blackboard() ....
80 
81  bool res = move_to.go( goal );
82  // convert bool to NodeStatus
83  return res ? NodeStatus::SUCCESS : NodeStatus::FAILURE;
84  };
85 
86  BehaviorTreeFactory factory;
87  // Register the lambda with BehaviorTreeFactory::registerSimpleAction
88  factory.registerSimpleAction("MoveTo", MoveToWrapperWithLambda);
89 
90  auto blackboard = Blackboard::create<BlackboardLocal>();
91  auto tree = buildTreeFromText(factory, xml_text, blackboard);
92 
93  // We set the entry "myGoal" in the blackboard.
94  Point3D my_goal = {3,4,5};
95  blackboard->set("myGoal", my_goal);
96 
97  NodeStatus status = NodeStatus::RUNNING;
98  while (status == NodeStatus::RUNNING)
99  {
100  status = tree.root_node->executeTick();
101  }
102  return 0;
103 }
104 
105 /* Expected output:
106 
107 Going to: -1.000000 3.000000 0.500000
108 Going to: 3.000000 4.000000 5.000000
109 
110 The first MoveTo read the parameter from the string "-1;3;0.5"
111 whilst the second from the blackboard, that contains a copy of the Point3D my_goal.
112 
113 */
double convertFromString< double >(const StringView &str)
Definition: basic_types.cpp:92
Point3D convertFromString(const StringView &key)
std::vector< StringView > splitString(const StringView &strToSplit, char delimeter)
bool go(Point3D goal)
nonstd::string_view StringView
Definition: basic_types.h:58
void registerSimpleAction(const std::string &ID, const SimpleActionNode::TickFunctor &tick_functor)
Register a SimpleActionNode.
Definition: bt_factory.cpp:85
const std::string xml_text
int main()
NodeStatus
Definition: basic_types.h:28
Tree buildTreeFromText(const BehaviorTreeFactory &factory, const std::string &text, const Blackboard::Ptr &blackboard=Blackboard::Ptr())


behaviortree_cpp
Author(s): Michele Colledanchise, Davide Faconti
autogenerated on Sun Feb 3 2019 03:14:32