add camera limit script

src/CameraLimit.cpp

@@ -0,0 +1,52 @@
+#include "CameraLimit.h"
+
+#include <SceneTree.hpp>
+#include <TileMap.hpp>
+#include <Camera2D.hpp>
+#include <Viewport.hpp>
+#include <Node.hpp>
+
+using namespace godot;
+
+void CameraLimit::_register_methods()
+{
+    register_method("_ready", &CameraLimit::_ready);
+}
+
+CameraLimit::CameraLimit()
+{
+}
+
+CameraLimit::~CameraLimit()
+{
+}
+
+void CameraLimit::_init()
+{
+}
+
+void CameraLimit::_ready()
+{
+    auto node = find_node("Middleground");
+    auto middle_ground = cast_to<TileMap>(node);
+    if (middle_ground != NULL)
+    {
+        auto used_rect = middle_ground->get_used_rect();
+        auto bounds = Vector2(used_rect.position.x + used_rect.size.x, used_rect.position.y + used_rect.size.y - 1);
+        node = get_tree()->get_root()->find_node("Camera2D", true, false);
+        auto camera = cast_to<Camera2D>(node);
+        if (camera != NULL)
+        {
+            camera->set_limit(2, bounds.x * middle_ground->get_cell_size().x);
+            camera->set_limit(3, bounds.y * middle_ground->get_cell_size().y);
+        }
+        else
+        {
+            ERR_PRINT("Could not find Camera2D node!");
+        }
+    }
+    else
+    {
+        ERR_PRINT("Could not find Middleground node!");
+    }
+}