6 files changed, 23 insertions, 20 deletions

diff --git a/src/crepe/system/CMakeLists.txt b/src/crepe/system/CMakeLists.txt
index 9ee12f6..2fb58dc 100644
--- a/src/crepe/system/CMakeLists.txt
+++ b/src/crepe/system/CMakeLists.txt
@@ -1,8 +1,8 @@
 target_sources(crepe PUBLIC
 	System.cpp
-	# ParticleSystem.cpp
+	ParticleSystem.cpp
 	ScriptSystem.cpp
-	# PhysicsSystem.cpp
+	PhysicsSystem.cpp
 	# CollisionSystem.cpp
 	# RenderSystem.cpp
 	# AnimatorSystem.cpp
@@ -11,7 +11,7 @@ target_sources(crepe PUBLIC
 target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	System.h
 	ScriptSystem.h
-	# PhysicsSystem.h
+	PhysicsSystem.h
 	# CollisionSystem.h
 	# RenderSystem.h
 	# AnimatorSystem.h
diff --git a/src/crepe/system/ParticleSystem.cpp b/src/crepe/system/ParticleSystem.cpp
index 397b586..64fee4e 100644
--- a/src/crepe/system/ParticleSystem.cpp
+++ b/src/crepe/system/ParticleSystem.cpp
@@ -8,10 +8,8 @@
 
 using namespace crepe;
 
-ParticleSystem::ParticleSystem() : elapsed_time(0.0f) {}
-
 void ParticleSystem::update() {
-	ComponentManager & mgr = ComponentManager::get_instance();
+	ComponentManager & mgr = this->component_manager;
 	std::vector<std::reference_wrapper<ParticleEmitter>> emitters
 		= mgr.get_components_by_type<ParticleEmitter>();
 	float delta_time = 0.10;
@@ -60,3 +58,4 @@ void ParticleSystem::emit_particle(ParticleEmitter & emitter) {
 		}
 	}
 }
+
diff --git a/src/crepe/system/ParticleSystem.h b/src/crepe/system/ParticleSystem.h
index 3ac1d3f..f171c62 100644
--- a/src/crepe/system/ParticleSystem.h
+++ b/src/crepe/system/ParticleSystem.h
@@ -2,17 +2,22 @@
 
 #include "../api/ParticleEmitter.h"
 
+#include "System.h"
+
 namespace crepe {
 
-class ParticleSystem {
+class ParticleSystem : public System {
 public:
-	ParticleSystem();
-	void update();
+	using System::System;
+	void update() override;
 
 private:
-	void emit_particle(ParticleEmitter & emitter); //emits a new particle
+	//! Emits a new particle
+	void emit_particle(ParticleEmitter & emitter);
 
-	float elapsed_time; //elapsed time since the last emission
+	//! Elapsed time since the last emission
+	float elapsed_time = 0.0;
+	// TODO: to std::chrono::duration
 };
 
 } // namespace crepe
diff --git a/src/crepe/system/PhysicsSystem.cpp b/src/crepe/system/PhysicsSystem.cpp
index eb54ad3..da79707 100644
--- a/src/crepe/system/PhysicsSystem.cpp
+++ b/src/crepe/system/PhysicsSystem.cpp
@@ -11,7 +11,7 @@
 using namespace crepe;
 
 void PhysicsSystem::update() {
-	ComponentManager & mgr = ComponentManager::get_instance();
+	ComponentManager & mgr = this->component_manager;
 	std::vector<std::reference_wrapper<Rigidbody>> rigidbodies
 		= mgr.get_components_by_type<Rigidbody>();
 	std::vector<std::reference_wrapper<Transform>> transforms
diff --git a/src/crepe/system/PhysicsSystem.h b/src/crepe/system/PhysicsSystem.h
index cc13b70..5433a0f 100644
--- a/src/crepe/system/PhysicsSystem.h
+++ b/src/crepe/system/PhysicsSystem.h
@@ -1,24 +1,24 @@
 #pragma once
 
+#include "System.h"
+
 namespace crepe {
+
 /**
  * \brief System that controls all physics
  * 
  * This class is a physics system that uses a rigidbody and transform
  * to add physics to a game object.
  */
-class PhysicsSystem {
+class PhysicsSystem : public System {
 public:
-	/**
-	 * Constructor is default
-	 */
-	PhysicsSystem() = default;
+	using System::System;
 	/**
 	 * \brief updates the physics system.
 	 * 
 	 * It calculates new velocties and changes the postion in the transform.
 	 */
-	void update();
+	void update() override;
 };
 
 } // namespace crepe
diff --git a/src/crepe/system/ScriptSystem.h b/src/crepe/system/ScriptSystem.h
index b52e825..b0b4185 100644
--- a/src/crepe/system/ScriptSystem.h
+++ b/src/crepe/system/ScriptSystem.h
@@ -7,12 +7,11 @@
 namespace crepe {
 
 class Script;
-class BehaviorScript;
 
 class ScriptSystem : public System {
 public:
 	using System::System;
-	void update();
+	void update() override;
 
 private:
 	std::forward_list<std::reference_wrapper<Script>> get_scripts();