From 80bc1e7b8bc6b66d1e2725b1f2a59893c64e767f Mon Sep 17 00:00:00 2001
From: Blu3train <frtempra@gmail.com>
Date: Fri, 2 Jun 2023 00:17:49 +0200
Subject: [PATCH] GameMaker engine hook

---
 texthook/engine/engine.cc  | 42 ++++++++++++++++++++++++++++++++++++++
 texthook/engine/engine.h   |  1 +
 texthook/engine/match32.cc |  4 ++++
 3 files changed, 47 insertions(+)

diff --git a/texthook/engine/engine.cc b/texthook/engine/engine.cc
index c2c7abc..6ad4642 100644
--- a/texthook/engine/engine.cc
+++ b/texthook/engine/engine.cc
@@ -21728,6 +21728,48 @@ bool InsertNamcoPS2Hook()
 }
 #endif // 0
 
+bool GameMakerFilter(LPVOID data, DWORD *size, HookParam *, BYTE)
+{
+  CharFilter(reinterpret_cast<LPSTR>(data), reinterpret_cast<size_t*>(size), '#');
+  return true;
+}
+
+bool InsertGameMakerHook() 
+{
+  //by Blu3train
+    /*
+    * Sample games:
+    *   VA-11 Hall A
+    */
+  const BYTE bytes[] = {
+    0x85, 0xF6,                 // test esi,esi
+    0x74, XX,                   // je "VA-11 Hall A.exe"+D5014
+    0x85, 0xC0,                 // test eax,eax
+    0x74, XX,                   // je "VA-11 Hall A.exe"+D5014
+    0x50,                       // push eax
+    0x56                        // push esi          << hook here
+  };
+  enum { addr_offset = sizeof(bytes) - 1 };
+
+  ULONG range = min(processStopAddress - processStartAddress, MAX_REL_ADDR);
+  ULONG addr = MemDbg::findBytes(bytes, sizeof(bytes), processStartAddress, processStartAddress + range);
+  if (!addr) {
+    ConsoleOutput("vnreng:GameMaker: pattern not found");
+    return false;
+  }
+
+  HookParam hp = {};
+  hp.address = addr + addr_offset;
+  hp.offset = pusha_eax_off -4;
+  hp.index = 0;
+  hp.type = USING_STRING | NO_CONTEXT;
+  hp.filter_fun = GameMakerFilter;
+  ConsoleOutput("vnreng: INSERT GameMaker");
+  NewHook(hp, "GameMaker");
+  ConsoleOutput("vnreng:GameMaker: use regex filter .+\\]");
+  return true;
+}
+
 } // namespace Engine
 
 // EOF
diff --git a/texthook/engine/engine.h b/texthook/engine/engine.h
index 5e167b2..be2bfe2 100644
--- a/texthook/engine/engine.h
+++ b/texthook/engine/engine.h
@@ -156,6 +156,7 @@ bool InsertWillPlusHook();      // WillPlus: Rio.arc
 bool InsertWolfHook();          // Wolf: Data.wolf
 bool InsertYukaSystem2Hook();   // YukaSystem2: *.ykc
 bool InsertYurisHook();         // YU-RIS: *.ypf
+bool InsertGameMakerHook();     // GameMaker: GMResource.dll
 
 void InsertBrunsHook();         // Bruns: bruns.exe
 void InsertIronGameSystemHook();// IroneGameSystem: igs_sample.exe
diff --git a/texthook/engine/match32.cc b/texthook/engine/match32.cc
index fffc4c7..0433222 100644
--- a/texthook/engine/match32.cc
+++ b/texthook/engine/match32.cc
@@ -370,6 +370,10 @@ bool DetermineEngineByFile3()
 
 bool DetermineEngineByFile4()
 {
+  if (Util::CheckFile(L"GMResource.dll")) {
+    if (InsertGameMakerHook())
+      return true;
+  }
   if (Util::CheckFile(L"EAGLS.dll")) { // jichi 3/24/2014: E.A.G.L.S
     //ConsoleOutput("vnreng: IGNORE EAGLS");
     InsertEaglsHook();