Changed System to take World through constructor and store it instead, cause it makes more sense.

src/Game/Systems/HealthSystem.cpp

@@ -1,7 +1,7 @@
 #include "Systems/HealthSystem.h"
 
-HealthSystem::HealthSystem(EventBroker* eventBroker)
-    : System(eventBroker)
+HealthSystem::HealthSystem(World* m_World, EventBroker* eventBroker)
+    : System(m_World, eventBroker)
     , PureSystem("Health")
 {
     //subscribe/listenTo playerdamage,healthpickup events (using the eventBroker)
@@ -9,10 +9,10 @@ HealthSystem::HealthSystem(EventBroker* eventBroker)
     EVENT_SUBSCRIBE_MEMBER(m_EPlayerHealthPickup, &HealthSystem::OnPlayerHealthPickup);
 }
 
-void HealthSystem::UpdateComponent(World* world, EntityWrapper& entity, ComponentWrapper& component, double dt)
+void HealthSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& component, double dt)
 {
     //if entityID of health is 9 then the players ID is also 9 (player,health are connected to the same entity)
-    ComponentWrapper player = world->GetComponent(component.EntityID, "Player");
+    ComponentWrapper player = m_World->GetComponent(component.EntityID, "Player");
     double maxHealth = (double)component["MaxHealth"];
 
     //process the DeltaHealthVector and change the entitys health accordingly

src/Game/Systems/PlayerMovementSystem.cpp

@@ -1,6 +1,6 @@
 #include "Systems/PlayerMovementSystem.h"
 
-void PlayerMovementSystem::UpdateComponent(World* world, EntityWrapper& entity, ComponentWrapper& component, double dt)
+void PlayerMovementSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& component, double dt)
 {
     ComponentWrapper& cTransform = entity["Transform"];
     if (!entity.HasComponent("Physics")) {

src/Game/Systems/PlayerSpawnSystem.cpp

@@ -1,21 +1,21 @@
 #include "Systems/PlayerSpawnSystem.h"
 
-PlayerSpawnSystem::PlayerSpawnSystem(EventBroker* eventBroker) 
-    : System(eventBroker)
+PlayerSpawnSystem::PlayerSpawnSystem(World* m_World, EventBroker* eventBroker) 
+    : System(m_World, eventBroker)
 {
     EVENT_SUBSCRIBE_MEMBER(m_OnInputCommand, &PlayerSpawnSystem::OnInputCommand);
 }
 
-void PlayerSpawnSystem::Update(World* world, double dt)
+void PlayerSpawnSystem::Update(double dt)
 {
-    auto playerSpawns = world->GetComponents("PlayerSpawn");
+    auto playerSpawns = m_World->GetComponents("PlayerSpawn");
     if (playerSpawns == nullptr) {
         return;
     }
 
     for (auto& team : m_SpawnRequests) {
         for (auto& cPlayerSpawn : *playerSpawns) {
-            EntityWrapper spawner(world, cPlayerSpawn.EntityID);
+            EntityWrapper spawner(m_World, cPlayerSpawn.EntityID);
             if (!spawner.HasComponent("Spawner")) {
                 continue;
             }

src/Game/Systems/PlayerSystem.cpp

@@ -1,6 +1,6 @@
 #include "Systems/PlayerSystem.h"
 
-void PlayerSystem::UpdateComponent(World* world, EntityWrapper& entity, ComponentWrapper& component, double dt)
+void PlayerSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& component, double dt)
 {
     component["Velocity"] = glm::vec3(0.f, 0.f, 0.f);
     if ((bool&)component["Forward"] == true) {
@@ -18,7 +18,7 @@ void PlayerSystem::UpdateComponent(World* world, EntityWrapper& entity, Componen
     }
 
     if ((glm::vec3)component["Velocity"] != glm::vec3(0.f)) {
-        ComponentWrapper& transform = world->GetComponent(component.EntityID, "Transform");
+        ComponentWrapper& transform = m_World->GetComponent(component.EntityID, "Transform");
         (glm::vec3&)transform["Position"] += (glm::vec3)component["Velocity"];
     }
 }

src/Game/Systems/SpawnerSystem.cpp

@@ -1,6 +1,7 @@
 #include "Systems/SpawnerSystem.h"
 
-SpawnerSystem::SpawnerSystem(EventBroker* eventBroker) : System(eventBroker)
+SpawnerSystem::SpawnerSystem(World* world, EventBroker* eventBroker) 
+    : System(world, eventBroker)
 {
     EVENT_SUBSCRIBE_MEMBER(m_OnSpawnerSpawn, &SpawnerSystem::OnSpawnerSpawn);
 }