Fix walking while aiming on higher fps (#502) (#2663)

Author: Merlin

Client/mods/deathmatch/CClient.cpp

@@ -128,6 +128,7 @@ int CClient::ClientInitialize(const char* szArguments, CCoreInterface* pCore)
     pCore->GetCommands()->Add("debug2", "debug function 2", COMMAND_Debug2);
     pCore->GetCommands()->Add("debug3", "debug function 3", COMMAND_Debug3);
     pCore->GetCommands()->Add("debug4", "debug function 4", COMMAND_Debug4);
+    pCore->GetCommands()->Add("timestep", "timestep", COMMAND_TimeStep);
 #endif
 
     // Got any arguments?

Client/mods/deathmatch/ClientCommands.cpp

@@ -1035,6 +1035,12 @@ void COMMAND_Debug4(const char* szCmdLine)
     g_pClientGame->StartPlayback();
     return;
 }
+
+void COMMAND_TimeStep(const char* szCmdLine)
+{
+    g_pCore->GetConsole()->Printf("TimeStep: %f", *(float*)0xB7CB5C); // CTimer::ms_fTimeStep
+}
+
 #endif
 
 void COMMAND_ShowCollision(const char* szCmdLine)

Client/mods/deathmatch/ClientCommands.h

@@ -80,6 +80,7 @@ void COMMAND_Debug(const char* szCmdLine);
 void COMMAND_Debug2(const char* szCmdLine);
 void COMMAND_Debug3(const char* szCmdLine);
 void COMMAND_Debug4(const char* szCmdLine);
+void COMMAND_TimeStep(const char* szCmdLine);
 #endif
 
 // Commands enabled when development mode in on

Client/multiplayer_sa/CMultiplayerSA.cpp

@@ -1566,6 +1566,7 @@ void CMultiplayerSA::InitHooks()
     InitHooks_VehicleWeapons();
 
     InitHooks_Streaming();
+    InitHooks_FrameRateFixes();
 }
 
 // Used to store copied pointers for explosions in the FxSystem

Client/multiplayer_sa/CMultiplayerSA.h

@@ -78,6 +78,7 @@ class CMultiplayerSA : public CMultiplayer
     void                InitHooks_Direct3D();
     void                InitHooks_FixLineOfSightArgs();
     void                InitHooks_Streaming();
+    void                InitHooks_FrameRateFixes();
     CRemoteDataStorage* CreateRemoteDataStorage();
     void                DestroyRemoteDataStorage(CRemoteDataStorage* pData);
     void                AddRemoteDataStorage(CPlayerPed* pPed, CRemoteDataStorage* pData);

Client/multiplayer_sa/CMultiplayerSA_FrameRateFixes.cpp

@@ -0,0 +1,36 @@
+/*****************************************************************************
+ *
+ *  PROJECT:     Multi Theft Auto
+ *  LICENSE:     See LICENSE in the top level directory
+ *  FILE:        multiplayer_sa/CMultiplayerSA_FrameRateFixes.cpp
+ *
+ *  Multi Theft Auto is available from https://www.multitheftauto.com/
+ *
+ *****************************************************************************/
+
+#include "StdInc.h"
+
+constexpr float kOriginalTimeStep = 50.0f / 30.0f;
+
+#define HOOKPOS_CTaskSimpleUseGun__SetMoveAnim 0x61E4F2
+#define HOOKSIZE_CTaskSimpleUseGun__SetMoveAnim 0x6
+const unsigned int RETURN_CTaskSimpleUseGun__SetMoveAnim = 0x61E4F8;
+
+void _declspec(naked) HOOK_CTaskSimpleUseGun__SetMoveAnim()
+{
+    _asm {
+        fld ds:[0xB7CB5C]           // CTimer::ms_fTimeStep
+        fdiv kOriginalTimeStep      // 1.666f
+        fmul ds:[0x858B1C]          // 0.1f
+        fxch
+        fcom
+        fxch
+        fstp st(0)
+        jmp RETURN_CTaskSimpleUseGun__SetMoveAnim
+    }
+}
+
+void CMultiplayerSA::InitHooks_FrameRateFixes()
+{
+    EZHookInstall(CTaskSimpleUseGun__SetMoveAnim);
+}