Add function call helpers

src/Hook.cpp

@@ -32,7 +32,6 @@ Hook::Hook() : m_menu(nullptr), m_modules()
 
 void Hook::Initialize()
 {
-	Instances::Init();
 	Game::Init();
 
 	RegisterModules();

src/instance/Instance.cpp

@@ -0,0 +1,13 @@
+#include "Instance.h"
+
+#include "util/Hooking.h"
+
+void INSTANCE_Post(Instance* instance, int message, int data)
+{
+	Hooking::Call(0x4580B0, instance, message, data);
+}
+
+void INSTANCE_HideUnhideDrawGroup(Instance* instance, int drawGroup, int on)
+{
+	Hooking::Call(0x4319B0, instance, drawGroup, on);
+}

src/instance/Instance.h

@@ -15,6 +15,14 @@ struct Intro
 {
 };
 
+struct ObjectData
+{
+	unsigned __int16 version;
+	unsigned __int16 family;
+	unsigned __int16 id;
+	unsigned __int16 type;
+};
+
 struct HModel;
 struct SoundInstanceData;
 struct Body;
@@ -49,7 +57,11 @@ struct BaseInstance
 	Object* object;
 	Intro* intro;
 
-	char pad2[100];
+	char pad2[64];
+
+	unsigned int noDrawGroups;
+
+	char pad3[32];
 };
 
 struct Instance : BaseInstance
@@ -61,4 +73,7 @@ struct Instance : BaseInstance
 	char pad2[12];
 
 	int introUniqueID;
-};
+};
+
+void INSTANCE_Post(Instance* instance, int message, int data);
+void INSTANCE_HideUnhideDrawGroup(Instance* instance, int drawGroup, int on);

src/instance/Instances.cpp

@@ -1,12 +1,5 @@
 #include "Instances.h"
 
-static void(*INSTANCE_Post)(Instance*, int, int);
-
-void Instances::Init()
-{
-	INSTANCE_Post = reinterpret_cast<void(*)(Instance*, int, int)>(0x4580B0);
-}
-
 void Instances::Iterate(std::function<void(Instance*)> callback)
 {
 	auto first = *(Instance**)0x817D64;
@@ -15,9 +8,4 @@ void Instances::Iterate(std::function<void(Instance*)> callback)
 	{
 		callback(instance);
 	}
-}
-
-void Instances::Post(Instance* instance, int message, int data)
-{
-	INSTANCE_Post(instance, message, data);
 }

src/instance/Instances.h

@@ -7,8 +7,5 @@
 class Instances
 {
 public:
-	static void Init();
-
 	static void Iterate(std::function<void(Instance*)> callback);
-	static void Post(Instance* instance, int message, int data);
 };

src/modules/Skew.cpp

@@ -8,7 +8,7 @@ void Skew::ToggleSkew()
 	auto tracker = Game::GetGameTracker();
 
 	tracker->cheatMode = !tracker->cheatMode;
-	Instances::Post(tracker->playerInstance, 1048592, tracker->cheatMode);
+	INSTANCE_Post(tracker->playerInstance, 1048592, tracker->cheatMode);
 }
 
 void Skew::Process(UINT msg, WPARAM wParam)

src/util/Hooking.h

@@ -0,0 +1,20 @@
+#pragma once
+
+// Helpers for hooking and calling functions
+class Hooking
+{
+public:
+	// Calls a function
+	template<typename... Args>
+	static inline void Call(unsigned int address, Args... args)
+	{
+		reinterpret_cast<void(*)(Args...)>(address)(args...);
+	}
+
+	// Calls a function with a return value
+	template<typename T, typename... Args>
+	static inline T CallReturn(unsigned int address, Args... args)
+	{
+		reinterpret_cast<T(*)(Args...)>(address)(args...);
+	}
+};