Update README.md

Reviewed-on: http://gitea.drewcav.com/drew/FoCAPI/pulls/2

FoCAPI.vcxproj

@@ -167,6 +167,7 @@
     <ClCompile Include="functions\file_io.cpp" />
     <ClCompile Include="functions\players.cpp" />
     <ClCompile Include="functions\screen_text.cpp" />
+    <ClCompile Include="functions\game_object_type.cpp" />
   </ItemGroup>
   <ItemGroup>
     <None Include="powrprof.def" />

FoCAPI.vcxproj.filters

@@ -59,6 +59,9 @@
     <ClCompile Include="functions\functions.cpp">
       <Filter>Source Files\Functions</Filter>
     </ClCompile>
+    <ClCompile Include="functions\game_object_type.cpp">
+      <Filter>Source Files\Functions</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <None Include="powrprof.def">

README.md

@@ -4,11 +4,11 @@ A powrprof.dll hook which adds custom Lua functions to Forces of Corruption.
 
 ## Usage
 
-Drop powrprof.dll and MinHooks.x64.dll into the `/corruption/` folder of your Empire at War installation.
+Drop powrprof.dll and MinHooks.x64.dll into the `/corruption` folder of your Empire at War installation.
 Works with both the debug kit `StarWarsI.exe` and client version `StarWarsG.exe` of the Steam version.
 Not supported on disc / GoG versions (sorry).
 
-## Functions
+## Global Functions
 
 - Global `WriteToFile(file, text)` - Appends a line of text specified file in the game directory.
   - Parameter `file` string - The file name to append.
@@ -23,4 +23,8 @@ Not supported on disc / GoG versions (sorry).
   - Parameter `b` number? - The blue color component. Default: 1
   - Parameter `a` number? - The alpha component. Default: 1
 - Global `Remove_Tutorial_Text(key)` - Removes the line associated with the key.
-  - Parameter `key` string - The key used to identify the line when it was added.
+  - Parameter `key` string - The key used to identify the line when it was added.
+  
+## GameObjectTypeWrapper
+
+- `Get_Display_Name()` - Returns the localized text string display name of the object type.

functions/functions.h

@@ -11,3 +11,7 @@ void Register_All(lua_State* L);
 void Register_FileIO(lua_State* L);
 void Register_Players(lua_State* L);
 void Register_ScreenText(lua_State* L);
+
+// Called from the GameObjectTypeWrapper ctor hook (not from Register_All).
+// Registers custom member functions on each wrapper instance.
+void Register_GOTMembers(void* wrapper);

functions/game_object_type.cpp

@@ -0,0 +1,92 @@
+#include "functions.h"
+#include "../lua_hook.h"
+#include <windows.h>
+#include <string>
+#include <cstring>
+
+// Offset of SmartPtr<GameObjectTypeClass> within GameObjectTypeWrapper.
+// SmartPtr stores the raw pointer as its first member.
+static constexpr int OFFSET_OBJECT = 0x70;
+
+// MSVC std::wstring layout (x64, MSVC 14.0+).
+// Used to read the wstring* returned by GameTextClass::Get.
+struct MSVCWString {
+    union {
+        wchar_t buf[8];    // SSO buffer (up to 7 wchars + null)
+        wchar_t* ptr;      // heap pointer when capacity > 7
+    };
+    size_t size;
+    size_t capacity;       // <= 7 means SSO, > 7 means heap
+
+    const wchar_t* c_str() const { return (capacity <= 7) ? buf : ptr; }
+};
+
+// Custom member function registered on GameObjectTypeWrapper.
+// Signature matches LuaTable* __thiscall (LuaScriptClass*, LuaTable*).
+// On x64 this is the standard calling convention: this_wrapper in RCX, script in RDX, params in R8.
+static void* Lua_Get_Display_Name(void* this_wrapper, void* /*script*/, void* /*params*/)
+{
+    // 1. Get GameObjectTypeClass* from SmartPtr at offset 0x70
+    void* got_class = *(void**)((char*)this_wrapper + OFFSET_OBJECT);
+    if (!got_class)
+        return nullptr;
+
+    // 2. Get the text ID string (e.g. "TEXT_UNIT_X_WING") via Get_Text_Name_ID.
+    //    The game's function constructs a std::string into our buffer via copy-ctor.
+    //    Assumes shared CRT (both DLL and game link to vcruntime140.dll dynamically).
+    std::string text_id;
+    pfn_get_text_name_id(got_class, &text_id);
+
+    // 3. Resolve the localized display name via TheGameText.Get(text_id, false).
+    //    Returns a pointer to an internal wstring (the translated text).
+    MSVCWString* display_wstr = (MSVCWString*)pfn_game_text_get(g_the_game_text, &text_id, false);
+    if (!display_wstr)
+        return nullptr;
+
+    // 4. Convert the wide display name to a narrow (UTF-8) string for Lua.
+    const wchar_t* wdata = display_wstr->c_str();
+    int wlen = (int)display_wstr->size;
+
+    int narrow_len = WideCharToMultiByte(CP_UTF8, 0, wdata, wlen, nullptr, 0, nullptr, nullptr);
+    if (narrow_len <= 0)
+        return nullptr;
+
+    std::string narrow(narrow_len, '\0');
+    WideCharToMultiByte(CP_UTF8, 0, wdata, wlen, &narrow[0], narrow_len, nullptr, nullptr);
+
+    // 5. Create a LuaString (LuaValue<string>, 0x78 bytes) and return it.
+    void* lua_value = ::operator new(0x78);
+    if (!lua_value)
+        return nullptr;
+    memset(lua_value, 0, 0x78);
+    pfn_lua_value_ctor(lua_value, &narrow);
+
+    return pfn_return_variable(this_wrapper, lua_value);
+}
+
+void Register_GOTMembers(void* wrapper)
+{
+    if (!pfn_lmfw_ctor || !pfn_register_member)
+        return;
+    if (!pfn_get_text_name_id || !pfn_game_text_get || !g_the_game_text)
+        return;
+    if (!pfn_lua_value_ctor || !pfn_return_variable)
+        return;
+
+    // Allocate a LuaMemberFunctionWrapper<GameObjectTypeWrapper> (0x88 bytes).
+    void* lmfw = ::operator new(0x88);
+    if (!lmfw) return;
+    memset(lmfw, 0, 0x88);
+
+    // Build the 16-byte pointer-to-member-function structure.
+    // MSVC x64 multiple-inheritance PMF: [8-byte func addr][8-byte this-adjustment].
+    // this-adjustment is 0 (our function expects the full GameObjectTypeWrapper*).
+    alignas(8) uint8_t pmf[16] = {};
+    *(uintptr_t*)pmf = (uintptr_t)&Lua_Get_Display_Name;
+
+    // Construct the LuaMemberFunctionWrapper via the game's ctor.
+    pfn_lmfw_ctor(lmfw, wrapper, pmf, false);
+
+    // Register as a member callable via wrapper.Get_Display_Name()
+    pfn_register_member(wrapper, "Get_Display_Name", lmfw);
+}

lua_hook.cpp

@@ -21,6 +21,14 @@ fn_AddTutorialText     pfn_add_tutorial_text     = nullptr;
 fn_RemoveTutorialText  pfn_remove_tutorial_text  = nullptr;
 void*                  g_command_bar             = nullptr;
 fn_DebugPrint          pfn_debug_print           = nullptr;
+fn_RegisterMember      pfn_register_member       = nullptr;
+fn_LuaValueCtor        pfn_lua_value_ctor        = nullptr;
+fn_ReturnVariable      pfn_return_variable       = nullptr;
+fn_GotWrapperCtor      real_got_wrapper_ctor     = nullptr;
+fn_LmfwCtor            pfn_lmfw_ctor             = nullptr;
+fn_GetTextNameId       pfn_get_text_name_id      = nullptr;
+fn_GameTextGet         pfn_game_text_get         = nullptr;
+void*                  g_the_game_text           = nullptr;
 
 void register_global(lua_State* L, const char* name, lua_CFunction fn) {
 	pfn_pushstring(L, name);
@@ -28,6 +36,13 @@ void register_global(lua_State* L, const char* name, lua_CFunction fn) {
 	pfn_settable(L, LUA_GLOBALSINDEX);
 }
 
+// Fired every time the game constructs a GameObjectTypeWrapper
+static void* Hook_GOTWrapperCtor(void* this_wrapper) {
+	void* result = real_got_wrapper_ctor(this_wrapper);
+	Register_GOTMembers(this_wrapper);
+	return result;
+}
+
 // Fired every time the game creates a new Lua state
 static lua_State* Hook_lua_open() {
 	lua_State* L = real_lua_open();
@@ -84,6 +99,22 @@ bool LuaHook_Init() {
 	if (rvas->debug_print)
 		pfn_debug_print = (fn_DebugPrint)(base + rvas->debug_print);
 
+	if (rvas->register_member)
+		pfn_register_member = (fn_RegisterMember)(base + rvas->register_member);
+	if (rvas->lua_value_ctor)
+		pfn_lua_value_ctor = (fn_LuaValueCtor)(base + rvas->lua_value_ctor);
+	if (rvas->return_variable)
+		pfn_return_variable = (fn_ReturnVariable)(base + rvas->return_variable);
+
+	if (rvas->the_game_text)
+		g_the_game_text = (void*)(base + rvas->the_game_text);
+	if (rvas->get_string)
+		pfn_game_text_get = (fn_GameTextGet)(base + rvas->get_string);
+	if (rvas->got_get_text_name_id)
+		pfn_get_text_name_id = (fn_GetTextNameId)(base + rvas->got_get_text_name_id);
+	if (rvas->got_lmfw_ctor)
+		pfn_lmfw_ctor = (fn_LmfwCtor)(base + rvas->got_lmfw_ctor);
+
 	if (rvas->lua_newtable && rvas->lua_rawseti) {
 		pfn_newtable = (fn_lua_newtable)(base + rvas->lua_newtable);
 		pfn_rawseti  = (fn_lua_rawseti)(base + rvas->lua_rawseti);
@@ -103,6 +134,18 @@ bool LuaHook_Init() {
 		return false;
 	}
 
+	// Hook GameObjectTypeWrapper constructor to register custom member functions
+	if (rvas->got_wrapper_ctor && rvas->got_lmfw_ctor &&
+		pfn_register_member && pfn_lmfw_ctor &&
+		pfn_get_text_name_id && pfn_game_text_get && g_the_game_text &&
+		pfn_lua_value_ctor && pfn_return_variable)
+	{
+		void* got_ctor_target = (void*)(base + rvas->got_wrapper_ctor);
+		if (MH_CreateHook(got_ctor_target, &Hook_GOTWrapperCtor, (void**)&real_got_wrapper_ctor) == MH_OK) {
+			MH_EnableHook(got_ctor_target);
+		}
+	}
+
 	return true;
 }
 

lua_hook.h

@@ -20,6 +20,15 @@ typedef void         (*fn_MapVarToLua)(lua_State*, void*);        // LuaScriptCl
 typedef void         (*fn_AddTutorialText)(void*, void*, const char*, float, unsigned int, bool, void*); // CommandBarClass::Add_Tutorial_Text (inner)
 typedef void         (*fn_RemoveTutorialText)(void*, const char*);                                      // CommandBarClass::Remove_Tutorial_Text
 typedef void         (*fn_DebugPrint)(const char*);               // Debug_Print
+// Scripting internals (LuaUserVar) -- usable by any wrapper module
+typedef void         (*fn_RegisterMember)(void* uservar, const char* name, void* fn_ptr); // LuaUserVar::Register_Member
+typedef void         (*fn_LuaValueCtor)(void* lua_value, void* basic_string_ptr);         // LuaValue<>::LuaValue<>(basic_string<>*)
+typedef void*        (*fn_ReturnVariable)(void* uservar, void* lua_var);                  // LuaUserVar::Return_Variable(LuaVar*) -> LuaTable*
+// Game Object Type Wrapper internals
+typedef void*        (*fn_GotWrapperCtor)(void* this_wrapper);                            // GameObjectTypeWrapper::GameObjectTypeWrapper()
+typedef void*        (*fn_LmfwCtor)(void* lmfw, void* wrapper, void* pmf, bool use_maps); // LuaMemberFunctionWrapper<GameObjectTypeWrapper>::ctor
+typedef void*        (*fn_GetTextNameId)(void* got_class, void* out_string);              // GameObjectTypeClass::Get_Text_Name_ID() -- returns via hidden out-param
+typedef void*        (*fn_GameTextGet)(void* game_text, void* text_id_str, bool insert);  // GameTextClass::Get(basic_string*, bool) -- returns wstring*
 
 // Resolved function pointers (defined in lua_hook.cpp)
 extern fn_lua_open            real_lua_open;
@@ -39,6 +48,14 @@ extern fn_AddTutorialText     pfn_add_tutorial_text;
 extern fn_RemoveTutorialText  pfn_remove_tutorial_text;
 extern void*                  g_command_bar;
 extern fn_DebugPrint          pfn_debug_print;
+extern fn_RegisterMember      pfn_register_member;
+extern fn_LuaValueCtor        pfn_lua_value_ctor;
+extern fn_ReturnVariable      pfn_return_variable;
+extern fn_GotWrapperCtor      real_got_wrapper_ctor;
+extern fn_LmfwCtor            pfn_lmfw_ctor;
+extern fn_GetTextNameId       pfn_get_text_name_id;
+extern fn_GameTextGet         pfn_game_text_get;
+extern void*                  g_the_game_text;
 
 constexpr int LUA_GLOBALSINDEX = -10001;
 

rvas.h

@@ -12,20 +12,32 @@ struct LuaRVAs {
     uintptr_t lua_newtable;
     uintptr_t lua_rawseti;
 
+    // --- Scripts ---
+    uintptr_t get_script_from_state;   // LuaScriptClass::Get_Script_From_State (static)
+    uintptr_t map_var_to_lua;          // LuaScriptClass::Map_Var_To_Lua (member)
+    uintptr_t register_member;         // LuaUserVar::Register_Member(char*, LuaVar*)
+    uintptr_t lua_value_ctor;          // LuaValue<>::LuaValue<>(basic_string<>*)
+    uintptr_t return_variable;         // LuaUserVar::Return_Variable(LuaVar*)
+
+    // --- TheGameText ---
+	uintptr_t the_game_text;		  // TheGameText global object (data, not a function)
+	uintptr_t get_string;			  // GameTextClass::Get(char*, bool)
+
     // --- Players ---
     uintptr_t get_player_by_index;     // PlayerListClass::Get_Player_By_Index
     uintptr_t player_list;             // PlayerList global object (data, not a function)
     uintptr_t player_wrapper_create;   // PlayerWrapper::Create (static)
 
-    // --- Scripts ---
-    uintptr_t get_script_from_state;   // LuaScriptClass::Get_Script_From_State (static)
-    uintptr_t map_var_to_lua;          // LuaScriptClass::Map_Var_To_Lua (member)
-
     // --- Screen Text ---
     uintptr_t command_bar;             // TheCommandBar global object (data, not a function)
     uintptr_t add_tutorial_text;       // CommandBarClass::Add_Tutorial_Text (inner overload: wstring*, char*, float, uint, bool, RGBAClass*)
     uintptr_t remove_tutorial_text;    // CommandBarClass::Remove_Tutorial_Text(char*)
 
+    // --- Game Object Type Wrapper ---
+    uintptr_t got_wrapper_ctor;        // GameObjectTypeWrapper::GameObjectTypeWrapper()
+    uintptr_t got_get_text_name_id;    // GameObjectTypeClass::Get_Text_Name_ID()
+    uintptr_t got_lmfw_ctor;           // LuaMemberFunctionWrapper<GameObjectTypeWrapper>::LuaMemberFunctionWrapper<>()
+
     // --- Debug ---
     uintptr_t debug_print;             // Debug_Print(char*)
 };
@@ -42,20 +54,32 @@ constexpr LuaRVAs RVAs_StarWarsI = {
     0x12AC460, // lua_newtable
     0x12ACD70, // lua_rawseti
 
+    // --- Scripts ---
+    0x0537BB0, // LuaScriptClass::Get_Script_From_State
+    0x0536FE0, // LuaScriptClass::Map_Var_To_Lua
+    0x0046f51, // LuaUserVar::Register_Member
+    0x004df5e, // LuaValue<>::LuaValue<>
+    0x0058887, // LuaUserVar::Return_Variable
+
+    // --- TheGameText ---
+    0x18578b0, // TheGameText global object
+    0x002b4cc, // GameTextClass::Get
+
     // --- Players ---
     0x000b0e1, // PlayerListClass::Get_Player_By_Index
     0x1913158, // PlayerList global object
     0x0F12010, // PlayerWrapper::Create
 
-    // --- Scripts ---
-    0x0537BB0, // LuaScriptClass::Get_Script_From_State
-    0x0536FE0, // LuaScriptClass::Map_Var_To_Lua
-
     // --- Screen Text ---
     0x1916b80, // TheCommandBar global object
     0x003c83a, // CommandBarClass::Add_Tutorial_Text inner
     0x006e1eb, // CommandBarClass::Remove_Tutorial_Text
 
+    // --- Game Object Type Wrapper ---
+    0x004f6c9, // GameObjectTypeWrapper::GameObjectTypeWrapper()
+	0x007b747, // GameObjectTypeClass::Get_Text_Name_ID()
+    0x0f08450, // LuaMemberFunctionWrapper<GameObjectTypeWrapper>::ctor
+
     // --- Debug ---
     0x0476AE0, // Debug_Print
 };
@@ -72,20 +96,32 @@ constexpr LuaRVAs RVAs_StarWarsG = {
     0x07b9140, // lua_newtable
     0x07b9820, // lua_rawseti
 
+    // --- Scripts ---
+    0x0245790, // LuaScriptClass::Get_Script_From_State
+    0x0247700, // LuaScriptClass::Map_Var_To_Lua
+    0,         // LuaUserVar::Register_Member  -- not mapped
+    0,         // LuaString::LuaString         -- not mapped
+    0,         // LuaUserVar::Return_Variable  -- not mapped
+
+    // --- TheGameText ---
+    0, // TheGameText global object
+    0, // GameTextClass::Get
+
     // --- Players ---
     0x0294bc0, // PlayerListClass::Get_Player_By_Index
     0x0a16fd0, // PlayerList global object
     0x06019f0, // PlayerWrapper::Create
 
-    // --- Scripts ---
-    0x0245790, // LuaScriptClass::Get_Script_From_State
-    0x0247700, // LuaScriptClass::Map_Var_To_Lua
-
     // --- Screen Text ---
-    0x0b27f60, // TheCommandBar
+    0x0b27f60, // TheCommandBar global object
     0x02dfd10, // CommandBarClass::Add_Tutorial_Text inner
     0x02ff290, // CommandBarClass::Remove_Tutorial_Text
 
+    // --- Game Object Type Wrapper ---
+    0,         // GameObjectTypeWrapper::GameObjectTypeWrapper() -- not mapped
+    0,         // GameObjectTypeClass::Get_Text_Name_ID()        -- not mapped
+    0,         // LuaMemberFunctionWrapper<GameObjectTypeWrapper>::ctor -- not mapped
+
     // --- Debug ---
     0,         // Debug_Print (not mapped)
 };