Creation of the RTree Godot Class

Basic defintions, we are going to see if it fits the use case.

src/rectangletree.cpp

@@ -0,0 +1,43 @@
+#include "rectangletree.hpp"
+#include "godot_cpp/core/class_db.hpp"
+#include "godot_cpp/variant/packed_int32_array.hpp"
+#include "godot_cpp/variant/packed_vector2_array.hpp"
+#include "godot_cpp/variant/typed_array.hpp"
+
+RectangleTree::RectangleTree() {}
+
+void RectangleTree::_bind_methods() {
+  ClassDB::bind_method(
+      godot::D_METHOD("add", "min_bound", "max_bound", "polygon_index"),
+      &RectangleTree::add);
+  ClassDB::bind_method(godot::D_METHOD("remove", "point"),
+                       &RectangleTree::remove);
+  ClassDB::bind_method(godot::D_METHOD("query", "point"),
+                       &RectangleTree::query);
+}
+
+void RectangleTree::add(const Vector2 &min_bound, const Vector2 &max_bound,
+                        const int &polygon_index) {
+  // convert into c++ types from godot types
+  Rect rect = Rect(min_bound.x, min_bound.y, max_bound.x, max_bound.y);
+
+  tree.Insert(rect.min, rect.max, polygon_index);
+}
+
+void RectangleTree::remove(const int &polygon_index) {
+  tree.Remove(polygon_index);
+}
+
+PackedInt32Array RectangleTree::query(const Vector2 &point) {
+  Rect rect = Rect(point.x, point.y, point.x, point.y);
+
+  PackedInt32Array return_value;
+  auto callbackLambda = [&return_value](int index) {
+    return_value.push_back(index);
+    return true;
+  };
+
+  tree.Search(rect.min, rect.max, callbackLambda);
+
+  return return_value;
+}

src/rectangletree.hpp

@@ -0,0 +1,53 @@
+#pragma once
+
+#include "godot_cpp/classes/wrapped.hpp"
+#include "godot_cpp/variant/packed_int32_array.hpp"
+#include "godot_cpp/variant/packed_vector2_array.hpp"
+#include "godot_cpp/variant/vector2.hpp"
+#include "rtree.h"
+#include <godot_cpp/classes/object.hpp>
+#include <godot_cpp/classes/polygon2d.hpp>
+
+using namespace godot;
+
+template <class CoordType = float> struct RectTemplate {
+  RectTemplate() {}
+
+  RectTemplate(CoordType a_minX, CoordType a_minY, CoordType a_maxX,
+               CoordType a_maxY) {
+    min[0] = a_minX;
+    min[1] = a_minY;
+
+    max[0] = a_maxX;
+    max[1] = a_maxY;
+  }
+
+  bool operator==(const RectTemplate &o) const {
+    return min[0] == o.min[0] && min[1] == o.min[1] && max[0] == o.max[0] &&
+           max[1] == o.max[1];
+  }
+
+  CoordType min[2];
+  CoordType max[2];
+};
+
+// returns an index, accepts 2 dimension floats
+typedef RTree<int, float, 2> RecTree;
+typedef RectTemplate<float> Rect;
+
+class RectangleTree : public Object {
+  GDCLASS(RectangleTree, Object);
+
+protected:
+  RecTree tree;
+
+  static void _bind_methods();
+
+public:
+  RectangleTree();
+
+  void add(const Vector2 &min_bound, const Vector2 &max_bound,
+           const int &polgon_index);
+  void remove(const int &polygon_index);
+  PackedInt32Array query(const Vector2 &point);
+};

src/register_types.cpp

@@ -1,5 +1,6 @@
 #include "register_types.h"
 #include "godot_cpp/core/class_db.hpp"
+#include "rectangletree.hpp"
 #include "triangulization.hpp"
 
 #include <gdextension_interface.h>
@@ -13,7 +14,8 @@ void initialize_triangulation_module(ModuleInitializationLevel p_level) {
     return;
   }
 
-  GDREGISTER_CLASS(Triangulization)
+  GDREGISTER_CLASS(Triangulization);
+  GDREGISTER_CLASS(RectangleTree);
 }
 
 void uninitialize_triangulation_module(ModuleInitializationLevel p_level) {