Virtual Offsets (Source Mods)

2011-01-07T03:57:48Z

Samantharp: Added a link to Bernis, VTable offeset list to provide a more updated interference for developers, credit given clearly.

[[Category:Metamod:Source Development]]
== Calling virtual functions ==
I got this method from [[User:Mani|Mani]], who I believe got it from [[User:PM|Pavol Marko]]. Thank you!

I hope to expand on an actual explanation when I have the time (and understand it better). Hopefully, someone can expand on this, but for now I'll just post the examples and a list of the CCSPlayer virtual function table offsets.

== Offset Lists ==
==== Automated Offsets ====
You can get automatically updated offsets from Berni's VTable Offset list. It automatically updates the offsets when an update is pushed by valve, making it a very resourceful tool.
* [http://www.sourcemodplugins.org/gamedumper/vtableoffsets.php Automated Offsets - Thanks to Berni]
==== Counter-Strike: Source ====
* [[CCSPlayer Offset List (Counter-Strike: Source)|CCSPlayer]]
* [[CBaseCombatWeapon Offset List (Counter-Strike: Source)|CBaseCombatWeapon]]
* [[CCSGameRules Offset List (Counter-Strike: Source) | CCSGameRules]]
* [[CBaseGrenade Offset List (Counter-Strike: Source) | CBaseGrenade]]
* [[CDEagle Offset List (Counter-Strike: Source) | CDEagle]]

==== Day of Defeat: Source ====
* [[CDODPlayer Offset List (Day of Defeat: Source)|CDODPlayer]]

==== Dystopia ====
* [[CDYSPlayer Offset List (Dystopia)|CDYSPlayer]]

==== Empires v2.12 ====
* [[CSDKPlayer Offset List (Empires)|CSDKPlayer]]

==== Fortress Forever ====
* [[CFFPlayer Offset List (Fortress Forever)|CFFPlayer]]

==== Half-Life 2: Capture the Flag ====
* [[CHL2_Player Offset List (Half-Life 2: Capture the Flag)|CHL2_Player]]

==== Half-Life 2: Deathmatch ====
* [[CHL2MP_Player Offset List (Half-Life 2: Deathmatch)|CHL2MP_Player]]

==== Hidden: Source ====
* [[CSDKPlayer Offset List (Hidden: Source)|CSDKPlayer]]

==== Insurgency ====
* [[CINSPlayer Offset List (Insurgency)|CINSPlayer]]

==== Left 4 Dead ====
* [[CTerrorPlayer Offset List (Left 4 Dead)|CTerrorPlayer]]

==== Left 4 Dead 2 ====
* [[CTerrorPlayer Offset List (Left 4 Dead 2)|CTerrorPlayer]]

==== Obsidian Conflict ====
* [[CHL2MP_Player Offset List (Obsidian Conflict)|CHL2MP_Player]]

==== Pirates, Vikings, and Knights II ====
* [[CPVK2Player Offset List (Pirates, Vikings, and Knights II)|CPVK2Player]]

==== The Ship ====
* [[CShipPlayer Offset List (The Ship)|CShipPlayer]]

==== SourceForts ====
* [[CHL2MP_Player Offset List (SourceForts)|CHL2MP_Player]]

==== Synergy ====
* [[CHL2MP_Player Offset List (Synergy)|CHL2MP_Player]]

==== Synergy SteamWorks (Synergy Orange Box Edition)====
* [[CHL2MP_Player Offset List (SynergyOB)|CHL2MP_Player]]

==== Team Fortress 2 ====
* [[CTFPlayer Offset List (Team Fortress 2)|CTFPlayer]]

==== Zombie Master ====
* [[CHL2MP_Player Offset List (Zombie Master)|CHL2MP_Player]]

==== Zombie Panic: Source ====
* [[CHL2MP_Player Offset List (Zombie Panic: Source)|CHL2MP_Player]]
* [[CBasePlayer Offset List (Zombie Panic: Source)|CBasePlayer ]]

==== GoldenEye: Source ====
* [[CGEPlayer Offset List (GoldenEye: Source)|CGEPlayer]]

== How to use the examples ==

Basically, this lets you call any [[virtual function]] by knowing it's offset. A table is created for each class that lists the address of the function for each virtual function. This method takes advantage of that to call those addresses.

Look at the examples below and edit to match the function you want to call:
Use the offset for the function you want to call in this line. ([[CCSPlayer_offset_list_(SourceMM)]])
<cpp>void *func = vtable[m_Off_GiveNamedItem];</cpp>
Change this line to match your return type and parameters:
<cpp>union {CBaseEntity *(VfuncEmptyClass::*mfpnew)(const char *, int );</cpp>
Call the original function with your parameters (change the return type to match the function you're calling):
<cpp>return (CBaseEntity *) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)(ItemName, iSubType);</cpp>

You'll need to add an empty class for the union. Something like this:
<cpp>class VfuncEmptyClass {};</cpp>

== Examples ==

These examples are for CSS. Mani has created a set of macros to make this easier. If you ask nicely, maybe he'll give them to you or let you post them here.

<cpp>datamap_t *VFuncs::GetDataDescMap(CBaseEntity *pThisPtr)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_GetDataDescMap];

union {datamap_t *(VfuncEmptyClass::*mfpnew)();
#ifndef __linux__
void *addr; } u; u.addr = func;
#else /* GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0 */
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

return (datamap_t *) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)();

}

void VFuncs::SetModel(CBaseEntity *pThisPtr, const char *ModelName)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_SetModel];

union {void (VfuncEmptyClass::*mfpnew)(const char *);
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

(void) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)(ModelName);

}

void VFuncs::Teleport(CBaseEntity *pThisPtr, const Vector *newPosition, const QAngle *newAngles, const Vector *newVelocity)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_Teleport];

union {void (VfuncEmptyClass::*mfpnew)(const Vector *, const QAngle *, const Vector *);
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

(void) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)(newPosition, newAngles, newVelocity);

}

Vector VFuncs::EyePosition( CBaseEntity *pThisPtr )
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_EyePosition];

union {Vector (VfuncEmptyClass::*mfpnew)( void );
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

return (Vector) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)( );

}

QAngle &VFuncs::EyeAngles( CBaseEntity *pThisPtr )
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_EyeAngles];

union {QAngle& (VfuncEmptyClass::*mfpnew)( void );
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

return (QAngle&) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)( );

}

void VFuncs::Ignite(CBaseEntity *pThisPtr, float flFlameLifetime, bool bNPCOnly, float flSize, bool bCalledByLevelDesigner)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_Ignite];

union {void (VfuncEmptyClass::*mfpnew)(float , bool , float , bool );
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

(void) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)(flFlameLifetime, bNPCOnly, flSize, bCalledByLevelDesigner);

}

CBaseEntity *VFuncs::GiveNamedItem(CBaseEntity *pThisPtr, const char *ItemName, int iSubType)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_GiveNamedItem];

union {CBaseEntity *(VfuncEmptyClass::*mfpnew)(const char *, int );
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

return (CBaseEntity *) (reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)(ItemName, iSubType);
}

void VFuncs::CommitSuicide(CBaseEntity *pThisPtr)
{
void **this_ptr = *(void ***)&pThisPtr;
void **vtable = *(void ***)pThisPtr;
void *func = vtable[m_Off_CommitSuicide];

union {CBaseEntity *(VfuncEmptyClass::*mfpnew)( void );
#ifndef __linux__
void *addr; } u; u.addr = func;
#else // GCC's member function pointers all contain a this pointer adjustor. You'd probably set it to 0
struct {void *addr; intptr_t adjustor;} s; } u; u.s.addr = func; u.s.adjustor = 0;
#endif

(reinterpret_cast<VfuncEmptyClass*>(this_ptr)->*u.mfpnew)();
}
</cpp>

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Virtual Offsets (Source Mods)