From 75a3f16ffbf88debe5a147cdc9ae459ba6114c5b Mon Sep 17 00:00:00 2001
From: Silent <zdanio95@gmail.com>
Date: Fri, 1 Nov 2024 17:33:33 +0100
Subject: [PATCH] III/VC: Improve the way RwD3D8Get/SetRenderState is located

Improves compatibility with other mods and provides a safe fallback.

Fixes #65
---
 SilentPatch/Common.cpp                        |  5 +-
 SilentPatch/RWGTA.cpp                         | 46 +++++++++++++++++--
 SilentPatch/RWGTA.h                           |  6 +++
 SilentPatchIII/SilentPatchIII.vcxproj         |  1 +
 SilentPatchIII/SilentPatchIII.vcxproj.filters |  3 ++
 SilentPatchVC/SilentPatchVC.vcxproj           |  1 +
 SilentPatchVC/SilentPatchVC.vcxproj.filters   |  3 ++
 7 files changed, 59 insertions(+), 6 deletions(-)
 create mode 100644 SilentPatch/RWGTA.h

diff --git a/SilentPatch/Common.cpp b/SilentPatch/Common.cpp
index 8baeaa5..e64f88b 100644
--- a/SilentPatch/Common.cpp
+++ b/SilentPatch/Common.cpp
@@ -7,6 +7,7 @@
 #include "SVF.h"
 #include "ParseUtils.hpp"
 #include "Random.h"
+#include "RWGTA.h"
 
 #include "Utils/DelimStringReader.h"
 
@@ -195,6 +196,8 @@ namespace Common {
 			using namespace Memory;
 			using namespace hook::txn;
 
+			const bool HasRwD3D8 = RWGTA::Patches::TryLocateRwD3D8();
+
 			// Delayed patching
 			try
 			{
@@ -249,7 +252,7 @@ namespace Common {
 
 
 			// Fixed static shadows not rendering under fire and pickups
-			try
+			if (HasRwD3D8) try
 			{
 				using namespace StaticShadowAlphaFix;
 
diff --git a/SilentPatch/RWGTA.cpp b/SilentPatch/RWGTA.cpp
index 21e35de..71f2fea 100644
--- a/SilentPatch/RWGTA.cpp
+++ b/SilentPatch/RWGTA.cpp
@@ -4,6 +4,7 @@
 #define RwEngineInstance (*rwengine)
 
 #include <rwcore.h>
+#include "RWGTA.h"
 
 // GTA versions of RenderWare functions/macros for GTA III/Vice City
 // since we cannot use RwEngineInstance directly
@@ -39,14 +40,16 @@ void** rwengine = []() -> void** {
 	return nullptr;
 }();
 
-static void* varRwD3D8SetRenderState = Memory::ReadCallFrom( hook::get_pattern( "0F 8C ? ? ? ? 6A 05 6A 19", 10 ) );
-WRAPPER RwBool RwD3D8SetRenderState(RwUInt32 state, RwUInt32 value) { VARJMP(varRwD3D8SetRenderState); }
+static decltype(::RwD3D8SetRenderState)* fnRwD3D8SetRenderState;
+RwBool RwD3D8SetRenderState(RwUInt32 state, RwUInt32 value)
+{
+	return fnRwD3D8SetRenderState(state, value);
+}
 
-static RwUInt32* _rwD3D8RenderStates = *static_cast<RwUInt32**>(Memory::ReadCallFrom( hook::get_pattern( "0F 8C ? ? ? ? 6A 05 6A 19", 10 ), 8 + 3 ));
+static decltype(::RwD3D8GetRenderState)* fnRwD3D8GetRenderState;
 void RwD3D8GetRenderState(RwUInt32 state, void* value)
 {
-	RwUInt32* valuePtr = static_cast<RwUInt32*>(value);
-	*valuePtr = _rwD3D8RenderStates[ 2 * state ];
+	fnRwD3D8GetRenderState(state, value);
 }
 
 RwReal RwIm2DGetNearScreenZ()
@@ -66,3 +69,36 @@ RwBool RwRenderStateSet(RwRenderState state, void *value)
 
 // Unreachable stub
 RwBool RwMatrixDestroy(RwMatrix* mpMat) { assert(!"Unreachable!"); return TRUE; }
+
+bool RWGTA::Patches::TryLocateRwD3D8() try
+{
+	using namespace Memory;
+	using namespace hook::txn;
+
+	auto fnRwD3D8SetRenderState = [] {
+		try {
+			// Everything except for III Steam
+			return static_cast<decltype(RwD3D8SetRenderState)*>(get_pattern("39 0C C5 ? ? ? ? 74 31", -8));
+		} catch (const hook::txn_exception&) {
+			// III Steam
+			return static_cast<decltype(RwD3D8SetRenderState)*>(get_pattern("8B 0C C5 ? ? ? ? 3B CA", -8));
+		}
+	}();
+	auto fnRwD3D8GetRenderState = [] {
+		try {
+			// Everything except for III Steam
+			return static_cast<decltype(RwD3D8GetRenderState)*>(get_pattern("8B 0C C5 ? ? ? ? 89 0A C3", -8));
+		} catch (const hook::txn_exception&) {
+			// III Steam
+			return static_cast<decltype(RwD3D8GetRenderState)*>(get_pattern("8B 04 C5 ? ? ? ? 89 02 C3", -8));
+		}
+	}();
+
+	::fnRwD3D8SetRenderState = fnRwD3D8SetRenderState;
+	::fnRwD3D8GetRenderState = fnRwD3D8GetRenderState;
+	return true;
+}
+catch (const hook::txn_exception&)
+{
+	return false;
+}
\ No newline at end of file
diff --git a/SilentPatch/RWGTA.h b/SilentPatch/RWGTA.h
new file mode 100644
index 0000000..e184dc9
--- /dev/null
+++ b/SilentPatch/RWGTA.h
@@ -0,0 +1,6 @@
+#pragma once
+
+namespace RWGTA::Patches
+{
+	bool TryLocateRwD3D8();
+}
diff --git a/SilentPatchIII/SilentPatchIII.vcxproj b/SilentPatchIII/SilentPatchIII.vcxproj
index 1dfde18..4f2b048 100644
--- a/SilentPatchIII/SilentPatchIII.vcxproj
+++ b/SilentPatchIII/SilentPatchIII.vcxproj
@@ -73,6 +73,7 @@
     <ClInclude Include="..\SilentPatch\Maths.h" />
     <ClInclude Include="..\SilentPatch\ParseUtils.hpp" />
     <ClInclude Include="..\SilentPatch\Random.h" />
+    <ClInclude Include="..\SilentPatch\RWGTA.h" />
     <ClInclude Include="..\SilentPatch\StdAfx.h" />
     <ClInclude Include="..\SilentPatch\StoredCar.h" />
     <ClInclude Include="..\SilentPatch\SVF.h" />
diff --git a/SilentPatchIII/SilentPatchIII.vcxproj.filters b/SilentPatchIII/SilentPatchIII.vcxproj.filters
index c630dbd..17a2005 100644
--- a/SilentPatchIII/SilentPatchIII.vcxproj.filters
+++ b/SilentPatchIII/SilentPatchIII.vcxproj.filters
@@ -113,6 +113,9 @@
     <ClInclude Include="..\SilentPatch\Random.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\SilentPatch\RWGTA.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="..\SilentPatch\SilentPatch.rc">
diff --git a/SilentPatchVC/SilentPatchVC.vcxproj b/SilentPatchVC/SilentPatchVC.vcxproj
index f996dff..660d626 100644
--- a/SilentPatchVC/SilentPatchVC.vcxproj
+++ b/SilentPatchVC/SilentPatchVC.vcxproj
@@ -166,6 +166,7 @@
     <ClInclude Include="..\SilentPatch\Maths.h" />
     <ClInclude Include="..\SilentPatch\ParseUtils.hpp" />
     <ClInclude Include="..\SilentPatch\Random.h" />
+    <ClInclude Include="..\SilentPatch\RWGTA.h" />
     <ClInclude Include="..\SilentPatch\RWUtils.hpp" />
     <ClInclude Include="..\SilentPatch\StdAfx.h" />
     <ClInclude Include="..\SilentPatch\StoredCar.h" />
diff --git a/SilentPatchVC/SilentPatchVC.vcxproj.filters b/SilentPatchVC/SilentPatchVC.vcxproj.filters
index fe68fbd..84c775f 100644
--- a/SilentPatchVC/SilentPatchVC.vcxproj.filters
+++ b/SilentPatchVC/SilentPatchVC.vcxproj.filters
@@ -75,6 +75,9 @@
     <ClInclude Include="EntityVC.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\SilentPatch\RWGTA.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\SilentPatch\Timer.cpp">