4 files changed, 60 insertions, 11 deletions

diff --git a/src/crepe/api/AI.h b/src/crepe/api/AI.h
index d4bd9d3..35b8998 100644
--- a/src/crepe/api/AI.h
+++ b/src/crepe/api/AI.h
@@ -36,6 +36,8 @@ public:
 		if (on(PATH_FOLLOW)) flags ^= PATH_FOLLOW;
 	}
 
+	void add_path_node(vec2 node) { path.push_back(node); }
+
 public:
 	float max_force;
 
@@ -47,9 +49,21 @@ public:
 	float square_flee_panic_distance = 200.0f * 200.0f;
 	// The deceleration rate for the arrive behavior (higher values will make the entity decelerate faster (less overshoot))
 	float arrive_deceleration = 40.0f;
+	// The path to follow
+	std::vector<vec2> path;
+	// The distance from the path node at which the entity will move to the next node
+	float path_node_distance = 400.0f;
+	// Looping behavior for the path
+	bool path_loop = true;
 
 private:
+	// The flags for the behaviors
 	int flags = 0;
+	// The current path index
+	size_t path_index = 0;
+
+	// The AISystem is the only class that can access the private members of AI
+	friend class AISystem;
 };
 
 } // namespace crepe
diff --git a/src/crepe/system/AISystem.cpp b/src/crepe/system/AISystem.cpp
index ce3147f..55dc14c 100644
--- a/src/crepe/system/AISystem.cpp
+++ b/src/crepe/system/AISystem.cpp
@@ -55,11 +55,11 @@ vec2 AISystem::calculate(AI & ai) {
 		}
 	}
 	if (ai.on(AI::BehaviorType::PATH_FOLLOW)) {
-		/*vec2 force_to_add = this->path_follow(ai);
+		vec2 force_to_add = this->path_follow(ai);
 
 		if (!this->accumulate_force(ai, force, force_to_add)) {
 			return force;
-		}*/
+		}
 	}
 
 	return force;
@@ -138,3 +138,33 @@ vec2 AISystem::arrive(const AI & ai) {
 
 	return vec2{0, 0};
 }
+
+vec2 AISystem::path_follow(AI & ai) {
+	const Mediator & mediator = this->mediator;
+	ComponentManager & mgr = mediator.component_manager;
+	RefVector<Transform> transforms = mgr.get_components_by_id<Transform>(ai.game_object_id);
+	Transform & transform = transforms.front().get();
+	RefVector<Rigidbody> rigidbodies = mgr.get_components_by_id<Rigidbody>(ai.game_object_id);
+	Rigidbody & rigidbody = rigidbodies.front().get();
+
+	if (ai.path.empty()) {
+		return vec2{0, 0};
+	}
+
+	vec2 to_target = ai.path.at(ai.path_index) - transform.position;
+	if (to_target.length_squared() > ai.path_node_distance * ai.path_node_distance) {
+		ai.seek_target = ai.path.at(ai.path_index);
+	} else {
+		ai.path_index++;
+		if (ai.path_index >= ai.path.size()) {
+			if (ai.path_loop) {
+				ai.path_index = 0;
+			} else {
+				ai.path_index = ai.path.size() - 1;
+				return this->arrive(ai);
+			}
+		}
+	}
+
+	return this->seek(ai);
+}
diff --git a/src/crepe/system/AISystem.h b/src/crepe/system/AISystem.h
index 18f1c61..27861d9 100644
--- a/src/crepe/system/AISystem.h
+++ b/src/crepe/system/AISystem.h
@@ -20,7 +20,7 @@ private:
 	vec2 seek(const AI & ai);
 	vec2 flee(const AI & ai);
 	vec2 arrive(const AI & ai);
-	vec2 path_follow(const AI & ai);
+	vec2 path_follow(AI & ai);
 };
 
 } // namespace crepe
diff --git a/src/example/AITest.cpp b/src/example/AITest.cpp
index 319d0fe..d12a99a 100644
--- a/src/example/AITest.cpp
+++ b/src/example/AITest.cpp
@@ -25,10 +25,10 @@ class Script1 : public Script {
 	}
 
 	bool mousemove(const MouseMoveEvent & event) {
-		RefVector<AI> aivec = this->get_components<AI>();
+		/*RefVector<AI> aivec = this->get_components<AI>();
 		AI & ai = aivec.front().get();
 		ai.flee_target
-			= vec2{static_cast<float>(event.mouse_x), static_cast<float>(event.mouse_y)};
+			= vec2{static_cast<float>(event.mouse_x), static_cast<float>(event.mouse_y)};*/
 		return true;
 	}
 
@@ -46,21 +46,26 @@ public:
 		Mediator & mediator = this->mediator;
 		ComponentManager & mgr = mediator.component_manager;
 
-		GameObject game_object1 = mgr.new_object("", "", vec2{250, 250}, 0, 1);
+		GameObject game_object1 = mgr.new_object("", "", vec2{0, 0}, 0, 1);
 		GameObject game_object2 = mgr.new_object("", "", vec2{0, 0}, 0, 1);
 
 		Texture img = Texture("asset/texture/test_ap43.png");
 		game_object1.add_component<Sprite>(img, Color::MAGENTA,
 										   Sprite::FlipSettings{false, false}, 1, 1, 195);
-		AI & ai = game_object1.add_component<AI>(30);
-		ai.arrive_on();
-		ai.flee_on();
+		AI & ai = game_object1.add_component<AI>(300);
+		// ai.arrive_on();
+		// ai.flee_on();
+		ai.path_follow_on();
+		ai.add_path_node(vec2{1200, 1200});
+		ai.add_path_node(vec2{-1200, 1200});
+		ai.add_path_node(vec2{1200, -1200});
+		ai.add_path_node(vec2{-1200, -1200});
 		game_object1.add_component<Rigidbody>(Rigidbody::Data{
-			.mass = 0.5f, .max_linear_velocity = {21, 21}, // sqrt(21^2 + 21^2) = 30
+			.mass = 0.5f, .max_linear_velocity = {50, 50}, // sqrt(21^2 + 21^2) = 30
 		});
 		game_object1.add_component<BehaviorScript>().set_script<Script1>();
 
-		game_object2.add_component<Camera>(Color::WHITE, ivec2{1080, 720}, vec2{1036, 780},
+		game_object2.add_component<Camera>(Color::WHITE, ivec2{1080, 720}, vec2{5000, 5000},
 										   1.0f);
 	}