diff --git a/cl_dll/com_weapons.cpp b/cl_dll/com_weapons.cpp
index 5621149b..05c8bdf9 100644
--- a/cl_dll/com_weapons.cpp
+++ b/cl_dll/com_weapons.cpp
@@ -116,7 +116,7 @@ void HUD_PlaySound( const char *sound, float volume )
 	if( !g_runfuncs || !g_finalstate )
 		return;
 
-	gEngfuncs.pfnPlaySoundByNameAtLocation( sound, volume, (float *)&g_finalstate->playerstate.origin );
+	gEngfuncs.pfnPlaySoundByNameAtLocation( sound, volume, g_finalstate->playerstate.origin );
 }
 
 /*
@@ -138,7 +138,7 @@ void HUD_PlaybackEvent( int flags, const edict_t *pInvoker, unsigned short event
 	// Weapon prediction events are assumed to occur at the player's origin
 	org			= g_finalstate->playerstate.origin;
 	ang			= v_angles;
-	gEngfuncs.pfnPlaybackEvent( flags, pInvoker, eventindex, delay, (float *)&org, (float *)&ang, fparam1, fparam2, iparam1, iparam2, bparam1, bparam2 );
+	gEngfuncs.pfnPlaybackEvent( flags, pInvoker, eventindex, delay, org, ang, fparam1, fparam2, iparam1, iparam2, bparam1, bparam2 );
 }
 
 /*
diff --git a/dlls/client.cpp b/dlls/client.cpp
index 80b16945..f96302d0 100644
--- a/dlls/client.cpp
+++ b/dlls/client.cpp
@@ -1102,8 +1102,8 @@ void SetupVisibility( edict_t *pViewEntity, edict_t *pClient, unsigned char **pv
 		}
 	}
 
-	*pvs = ENGINE_SET_PVS( (float *)&org );
-	*pas = ENGINE_SET_PAS( (float *)&org );
+	*pvs = ENGINE_SET_PVS( org );
+	*pas = ENGINE_SET_PAS( org );
 }
 
 #include "entity_state.h"
diff --git a/dlls/crossbow.cpp b/dlls/crossbow.cpp
index 12d0ff8c..c3f73f4f 100644
--- a/dlls/crossbow.cpp
+++ b/dlls/crossbow.cpp
@@ -373,7 +373,7 @@ void CCrossbow::FireSniperBolt()
 	flags = 0;
 #endif
 
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usCrossbow2, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0, 0, m_iClip, m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType], 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usCrossbow2, 0.0, g_vecZero, g_vecZero, 0, 0, m_iClip, m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType], 0, 0 );
 
 	// player "shoot" animation
 	m_pPlayer->SetAnimation( PLAYER_ATTACK1 );
@@ -416,7 +416,7 @@ void CCrossbow::FireBolt()
 	flags = 0;
 #endif
 
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usCrossbow, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0, 0, m_iClip, m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType], 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usCrossbow, 0.0, g_vecZero, g_vecZero, 0, 0, m_iClip, m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType], 0, 0 );
 
 	// player "shoot" animation
 	m_pPlayer->SetAnimation( PLAYER_ATTACK1 );
diff --git a/dlls/crowbar.cpp b/dlls/crowbar.cpp
index 4cc48d97..8a0ba9a3 100644
--- a/dlls/crowbar.cpp
+++ b/dlls/crowbar.cpp
@@ -204,7 +204,7 @@ int CCrowbar::Swing( int fFirst )
 	if( fFirst )
 	{
 		PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usCrowbar, 
-		0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0, 0, 0,
+		0.0, g_vecZero, g_vecZero, 0, 0, 0,
 		0, 0, 0 );
 	}
 
diff --git a/dlls/egon.cpp b/dlls/egon.cpp
index b83c9086..6f248309 100644
--- a/dlls/egon.cpp
+++ b/dlls/egon.cpp
@@ -197,7 +197,7 @@ void CEgon::Attack( void )
 
 			m_flAmmoUseTime = gpGlobals->time;// start using ammo ASAP.
 
-			PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usEgonFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, m_fireState, m_fireMode, 1, 0 );
+			PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usEgonFire, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, m_fireState, m_fireMode, 1, 0 );
 		
 			m_shakeTime = 0;
 
@@ -216,7 +216,7 @@ void CEgon::Attack( void )
 
 			if( pev->fuser1 <= UTIL_WeaponTimeBase() )
 			{
-				PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usEgonFire, 0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, m_fireState, m_fireMode, 0, 0 );
+				PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usEgonFire, 0, g_vecZero, g_vecZero, 0.0, 0.0, m_fireState, m_fireMode, 0, 0 );
 				pev->fuser1 = 1000;
 			}
 
@@ -504,7 +504,7 @@ void CEgon::EndAttack( void )
 	if( m_fireState != FIRE_OFF ) //Checking the button just in case!.
 		 bMakeNoise = true;
 
-	PLAYBACK_EVENT_FULL( FEV_GLOBAL | FEV_RELIABLE, m_pPlayer->edict(), m_usEgonStop, 0, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, 0.0, 0.0, bMakeNoise, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( FEV_GLOBAL | FEV_RELIABLE, m_pPlayer->edict(), m_usEgonStop, 0, m_pPlayer->pev->origin, m_pPlayer->pev->angles, 0.0, 0.0, bMakeNoise, 0, 0, 0 );
 
 	m_flTimeWeaponIdle = UTIL_WeaponTimeBase() + 2.0;
 	m_flNextPrimaryAttack = m_flNextSecondaryAttack = UTIL_WeaponTimeBase() + 0.5;
diff --git a/dlls/gauss.cpp b/dlls/gauss.cpp
index 62af08e1..21377783 100644
--- a/dlls/gauss.cpp
+++ b/dlls/gauss.cpp
@@ -138,7 +138,7 @@ BOOL CGauss::Deploy()
 
 void CGauss::Holster( int skiplocal /* = 0 */ )
 {
-	PLAYBACK_EVENT_FULL( FEV_RELIABLE | FEV_GLOBAL, m_pPlayer->edict(), m_usGaussFire, 0.01, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );
+	PLAYBACK_EVENT_FULL( FEV_RELIABLE | FEV_GLOBAL, m_pPlayer->edict(), m_usGaussFire, 0.01, m_pPlayer->pev->origin, m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );
 
 	m_pPlayer->m_flNextAttack = UTIL_WeaponTimeBase() + 0.5;
 
@@ -217,7 +217,7 @@ void CGauss::SecondaryAttack()
 		m_pPlayer->m_flStartCharge = gpGlobals->time;
 		m_pPlayer->m_flAmmoStartCharge = UTIL_WeaponTimeBase() + GetFullChargeTime();
 
-		PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussSpin, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, 110, 0, 0, 0 );
+		PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussSpin, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, 110, 0, 0, 0 );
 
 		m_iSoundState = SND_CHANGE_PITCH;
 	}
@@ -281,7 +281,7 @@ void CGauss::SecondaryAttack()
 		if( m_iSoundState == 0 )
 			ALERT( at_console, "sound state %d\n", m_iSoundState );
 
-		PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussSpin, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, pitch, 0, ( m_iSoundState == SND_CHANGE_PITCH ) ? 1 : 0, 0 );
+		PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussSpin, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, pitch, 0, ( m_iSoundState == SND_CHANGE_PITCH ) ? 1 : 0, 0 );
 
 		m_iSoundState = SND_CHANGE_PITCH; // hack for going through level transitions
 
@@ -389,13 +389,13 @@ void CGauss::Fire( Vector vecOrigSrc, Vector vecDir, float flDamage )
 		 g_irunninggausspred = true;
 #endif	
 	// The main firing event is sent unreliably so it won't be delayed.
-	PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussFire, 0.0, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, flDamage, 0.0, 0, 0, m_fPrimaryFire ? 1 : 0, 0 );
+	PLAYBACK_EVENT_FULL( FEV_NOTHOST, m_pPlayer->edict(), m_usGaussFire, 0.0, m_pPlayer->pev->origin, m_pPlayer->pev->angles, flDamage, 0.0, 0, 0, m_fPrimaryFire ? 1 : 0, 0 );
 
 	// This reliable event is used to stop the spinning sound
 	// It's delayed by a fraction of second to make sure it is delayed by 1 frame on the client
 	// It's sent reliably anyway, which could lead to other delays
 
-	PLAYBACK_EVENT_FULL( FEV_NOTHOST | FEV_RELIABLE, m_pPlayer->edict(), m_usGaussFire, 0.01, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );
+	PLAYBACK_EVENT_FULL( FEV_NOTHOST | FEV_RELIABLE, m_pPlayer->edict(), m_usGaussFire, 0.01, m_pPlayer->pev->origin, m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );
 
 	/*ALERT( at_console, "%f %f %f\n%f %f %f\n", 
 		vecSrc.x, vecSrc.y, vecSrc.z, 
diff --git a/dlls/glock.cpp b/dlls/glock.cpp
index 1150d8b9..89dd189e 100644
--- a/dlls/glock.cpp
+++ b/dlls/glock.cpp
@@ -168,7 +168,7 @@ void CGlock::GlockFire( float flSpread, float flCycleTime, BOOL fUseAutoAim )
 	Vector vecDir;
 	vecDir = m_pPlayer->FireBulletsPlayer( 1, vecSrc, vecAiming, Vector( flSpread, flSpread, flSpread ), 8192, BULLET_PLAYER_9MM, 0, 0, m_pPlayer->pev, m_pPlayer->random_seed );
 
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), fUseAutoAim ? m_usFireGlock1 : m_usFireGlock2, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, vecDir.x, vecDir.y, 0, 0, ( m_iClip == 0 ) ? 1 : 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), fUseAutoAim ? m_usFireGlock1 : m_usFireGlock2, 0.0, g_vecZero, g_vecZero, vecDir.x, vecDir.y, 0, 0, ( m_iClip == 0 ) ? 1 : 0, 0 );
 
 	m_flNextPrimaryAttack = m_flNextSecondaryAttack = GetNextAttackDelay( flCycleTime );
 
diff --git a/dlls/hornetgun.cpp b/dlls/hornetgun.cpp
index cc63d6db..909ba342 100644
--- a/dlls/hornetgun.cpp
+++ b/dlls/hornetgun.cpp
@@ -150,7 +150,7 @@ void CHgun::PrimaryAttack()
 #else
 	flags = 0;
 #endif
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usHornetFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, FIREMODE_TRACK, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usHornetFire, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, FIREMODE_TRACK, 0, 0, 0 );
 
 	// player "shoot" animation
 	m_pPlayer->SetAnimation( PLAYER_ATTACK1 );
@@ -231,7 +231,7 @@ void CHgun::SecondaryAttack( void )
 #else
 	flags = 0;
 #endif
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usHornetFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, FIREMODE_FAST, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usHornetFire, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, FIREMODE_FAST, 0, 0, 0 );
 
 	m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType]--;
 	m_pPlayer->m_iWeaponVolume = NORMAL_GUN_VOLUME;
diff --git a/dlls/mp5.cpp b/dlls/mp5.cpp
index 403efa04..426f738a 100644
--- a/dlls/mp5.cpp
+++ b/dlls/mp5.cpp
@@ -171,7 +171,7 @@ void CMP5::PrimaryAttack()
 #else
 	flags = 0;
 #endif
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usMP5, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usMP5, 0.0, g_vecZero, g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
 
 	if( !m_iClip && m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType] <= 0 )
 		// HEV suit - indicate out of ammo condition
diff --git a/dlls/plats.cpp b/dlls/plats.cpp
index b3e1c683..5a96a36b 100644
--- a/dlls/plats.cpp
+++ b/dlls/plats.cpp
@@ -1059,7 +1059,7 @@ void CFuncTrackTrain::StopSound( void )
 		us_encode = us_sound;
 
 		PLAYBACK_EVENT_FULL( FEV_RELIABLE | FEV_UPDATE, edict(), m_usAdjustPitch, 0.0, 
-			(float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, us_encode, 0, 1, 0 );
+			g_vecZero, g_vecZero, 0.0, 0.0, us_encode, 0, 1, 0 );
 		/*
 		STOP_SOUND( ENT( pev ), CHAN_STATIC, STRING( pev->noise ) );
 		*/
@@ -1107,7 +1107,7 @@ void CFuncTrackTrain::UpdateSound( void )
 		us_encode = us_sound | us_pitch | us_volume;
 
 		PLAYBACK_EVENT_FULL( FEV_RELIABLE | FEV_UPDATE, edict(), m_usAdjustPitch, 0.0,
-			(float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, us_encode, 0, 0, 0 );
+			g_vecZero, g_vecZero, 0.0, 0.0, us_encode, 0, 0, 0 );
 	}
 }
 
diff --git a/dlls/python.cpp b/dlls/python.cpp
index 90606c50..88aa34b5 100644
--- a/dlls/python.cpp
+++ b/dlls/python.cpp
@@ -200,7 +200,7 @@ void CPython::PrimaryAttack()
 #else
 	flags = 0;
 #endif
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usFirePython, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usFirePython, 0.0, g_vecZero, g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
 
 	if( !m_iClip && m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType] <= 0 )
 		// HEV suit - indicate out of ammo condition
diff --git a/dlls/shotgun.cpp b/dlls/shotgun.cpp
index a08770b3..03944087 100644
--- a/dlls/shotgun.cpp
+++ b/dlls/shotgun.cpp
@@ -166,7 +166,7 @@ void CShotgun::PrimaryAttack()
 		vecDir = m_pPlayer->FireBulletsPlayer( 6, vecSrc, vecAiming, VECTOR_CONE_10DEGREES, 2048, BULLET_PLAYER_BUCKSHOT, 0, 0, m_pPlayer->pev, m_pPlayer->random_seed );
 	}
 
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usSingleFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usSingleFire, 0.0, g_vecZero, g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
 
 	if( !m_iClip && m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType] <= 0 )
 		// HEV suit - indicate out of ammo condition
@@ -237,7 +237,7 @@ void CShotgun::SecondaryAttack( void )
 		vecDir = m_pPlayer->FireBulletsPlayer( 12, vecSrc, vecAiming, VECTOR_CONE_10DEGREES, 2048, BULLET_PLAYER_BUCKSHOT, 0, 0, m_pPlayer->pev, m_pPlayer->random_seed );
 	}
 
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usDoubleFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usDoubleFire, 0.0, g_vecZero, g_vecZero, vecDir.x, vecDir.y, 0, 0, 0, 0 );
 
 	if( !m_iClip && m_pPlayer->m_rgAmmo[m_iPrimaryAmmoType] <= 0 )
 		// HEV suit - indicate out of ammo condition
diff --git a/dlls/squeakgrenade.cpp b/dlls/squeakgrenade.cpp
index bfe17ed1..a7295599 100644
--- a/dlls/squeakgrenade.cpp
+++ b/dlls/squeakgrenade.cpp
@@ -508,7 +508,7 @@ void CSqueak::PrimaryAttack()
 #else
 		flags = 0;
 #endif
-		PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usSnarkFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
+		PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usSnarkFire, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
 
 		if( tr.fAllSolid == 0 && tr.fStartSolid == 0 && tr.flFraction > 0.25 )
 		{
diff --git a/dlls/tripmine.cpp b/dlls/tripmine.cpp
index 94907bcd..6e8fc2fc 100644
--- a/dlls/tripmine.cpp
+++ b/dlls/tripmine.cpp
@@ -444,7 +444,7 @@ void CTripmine::PrimaryAttack( void )
 #else
 	flags = 0;
 #endif
-	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usTripFire, 0.0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
+	PLAYBACK_EVENT_FULL( flags, m_pPlayer->edict(), m_usTripFire, 0.0, g_vecZero, g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
 
 	if( tr.flFraction < 1.0 )
 	{
diff --git a/dlls/util.h b/dlls/util.h
index 41e86a84..602380ba 100644
--- a/dlls/util.h
+++ b/dlls/util.h
@@ -552,8 +552,8 @@ void EMIT_GROUPNAME_SUIT(edict_t *entity, const char *groupname);
 
 #define RANDOM_SOUND_ARRAY( array ) (array) [ RANDOM_LONG(0,ARRAYSIZE( (array) )-1) ]
 
-#define PLAYBACK_EVENT( flags, who, index ) PLAYBACK_EVENT_FULL( flags, who, index, 0, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
-#define PLAYBACK_EVENT_DELAY( flags, who, index, delay ) PLAYBACK_EVENT_FULL( flags, who, index, delay, (float *)&g_vecZero, (float *)&g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
+#define PLAYBACK_EVENT( flags, who, index ) PLAYBACK_EVENT_FULL( flags, who, index, 0, g_vecZero, g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
+#define PLAYBACK_EVENT_DELAY( flags, who, index, delay ) PLAYBACK_EVENT_FULL( flags, who, index, delay, g_vecZero, g_vecZero, 0.0, 0.0, 0, 0, 0, 0 );
 
 #define GROUP_OP_AND	0
 #define GROUP_OP_NAND	1
diff --git a/engine/cdll_int.h b/engine/cdll_int.h
index abfc43bd..8ab903b0 100644
--- a/engine/cdll_int.h
+++ b/engine/cdll_int.h
@@ -169,7 +169,7 @@ typedef struct cl_enginefuncs_s
 	int	(*GetWindowCenterX)( void );
 	int	(*GetWindowCenterY)( void );
 	void	(*GetViewAngles)( float * );
-	void	(*SetViewAngles)( float * );
+	void	(*SetViewAngles)( const float * );
 	int	(*GetMaxClients)( void );
 	void	(*Cvar_SetValue)( const char *cvar, float value );
 
@@ -195,20 +195,20 @@ typedef struct cl_enginefuncs_s
 
 	float	(*GetClientTime)( void );
 	void	(*V_CalcShake)( void );
-	void	(*V_ApplyShake)( float *origin, float *angles, float factor );
+	void	(*V_ApplyShake)( const float *origin, const float *angles, float factor );
 
-	int	(*PM_PointContents)( float *point, int *truecontents );
-	int	(*PM_WaterEntity)( float *p );
-	struct pmtrace_s *(*PM_TraceLine)( float *start, float *end, int flags, int usehull, int ignore_pe );
+	int	(*PM_PointContents)( const float *point, int *truecontents );
+	int	(*PM_WaterEntity)( const float *p );
+	struct pmtrace_s *(*PM_TraceLine)( const float *start, const float *end, int flags, int usehull, int ignore_pe );
 
 	struct model_s *(*CL_LoadModel)( const char *modelname, int *index );
 	int	(*CL_CreateVisibleEntity)( int type, struct cl_entity_s *ent );
 
 	const struct model_s* (*GetSpritePointer)( HSPRITE hSprite );
-	void	(*pfnPlaySoundByNameAtLocation)( const char *szSound, float volume, float *origin );
+	void	(*pfnPlaySoundByNameAtLocation)( const char *szSound, float volume, const float *origin );
 	
 	unsigned short (*pfnPrecacheEvent)( int type, const char* psz );
-	void	(*pfnPlaybackEvent)( int flags, const struct edict_s *pInvoker, unsigned short eventindex, float delay, float *origin, float *angles, float fparam1, float fparam2, int iparam1, int iparam2, int bparam1, int bparam2 );
+	void	(*pfnPlaybackEvent)( int flags, const struct edict_s *pInvoker, unsigned short eventindex, float delay, const float *origin, const float *angles, float fparam1, float fparam2, int iparam1, int iparam2, int bparam1, int bparam2 );
 	void	(*pfnWeaponAnim)( int iAnim, int body );
 	float	(*pfnRandomFloat)( float flLow, float flHigh );	
 	int	(*pfnRandomLong)( int lLow, int lHigh );
diff --git a/engine/eiface.h b/engine/eiface.h
index f6cf2f51..cad60848 100644
--- a/engine/eiface.h
+++ b/engine/eiface.h
@@ -124,7 +124,7 @@ typedef struct enginefuncs_s
 	int	(*pfnWalkMove)( edict_t *ent, float yaw, float dist, int iMode );
 	void	(*pfnSetOrigin)( edict_t *e, const float *rgflOrigin );
 	void	(*pfnEmitSound)( edict_t *entity, int channel, const char *sample, /*int*/float volume, float attenuation, int fFlags, int pitch );
-	void	(*pfnEmitAmbientSound)( edict_t *entity, float *pos, const char *samp, float vol, float attenuation, int fFlags, int pitch );
+	void	(*pfnEmitAmbientSound)( edict_t *entity, const float *pos, const char *samp, float vol, float attenuation, int fFlags, int pitch );
 	void	(*pfnTraceLine)( const float *v1, const float *v2, int fNoMonsters, edict_t *pentToSkip, TraceResult *ptr );
 	void	(*pfnTraceToss)( edict_t* pent, edict_t* pentToIgnore, TraceResult *ptr );
 	int	(*pfnTraceMonsterHull)( edict_t *pEdict, const float *v1, const float *v2, int fNoMonsters, edict_t *pentToSkip, TraceResult *ptr );
@@ -219,10 +219,10 @@ typedef struct enginefuncs_s
 	void	(*pfnSetPhysicsKeyValue)( const edict_t *pClient, const char *key, const char *value );
 	const char *(*pfnGetPhysicsInfoString)( const edict_t *pClient );
 	unsigned short (*pfnPrecacheEvent)( int type, const char*psz );
-	void	(*pfnPlaybackEvent)( int flags, const edict_t *pInvoker, unsigned short eventindex, float delay, float *origin, float *angles, float fparam1, float fparam2, int iparam1, int iparam2, int bparam1, int bparam2 );
-	
-	unsigned char *(*pfnSetFatPVS)( float *org );
-	unsigned char *(*pfnSetFatPAS)( float *org );
+	void	(*pfnPlaybackEvent)( int flags, const edict_t *pInvoker, unsigned short eventindex, float delay, const float *origin, const float *angles, float fparam1, float fparam2, int iparam1, int iparam2, int bparam1, int bparam2 );
+
+	unsigned char *(*pfnSetFatPVS)( const float *org );
+	unsigned char *(*pfnSetFatPAS)( const float *org );
 
 	int	(*pfnCheckVisibility )( const edict_t *entity, unsigned char *pset );
 
@@ -241,7 +241,7 @@ typedef struct enginefuncs_s
 	// Forces the client and server to be running with the same version of the specified file
 	//  ( e.g., a player model ).
 	// Calling this has no effect in single player
-	void	(*pfnForceUnmodified)( FORCE_TYPE type, float *mins, float *maxs, const char *filename );
+	void	(*pfnForceUnmodified)( FORCE_TYPE type, const float *mins, const float *maxs, const char *filename );
 
 	void	(*pfnGetPlayerStats)( const edict_t *pClient, int *ping, int *packet_loss );