Introduce air friction as a replacement for the hard speed cap to prevent ghost hopping

src/game/client/neo/c_neo_player.cpp

@@ -833,7 +833,6 @@ void C_NEO_Player::PlayStepSound( Vector &vecOrigin,
 	BaseClass::PlayStepSound(vecOrigin, psurface, fvol, force);
 }
 
-extern ConVar neo_ghost_bhopping;
 void C_NEO_Player::CalculateSpeed(void)
 {
 	float speed = GetNormSpeed();
@@ -877,17 +876,6 @@ void C_NEO_Player::CalculateSpeed(void)
 		speed = MIN(GetFlags() & FL_DUCKING ? NEO_CROUCH_WALK_SPEED : NEO_WALK_SPEED, speed);
 	}
 
-	Vector absoluteVelocity = GetAbsVelocity();
-	absoluteVelocity.z = 0.f;
-	float currentSpeed = absoluteVelocity.Length();
-
-	if (((!neo_ghost_bhopping.GetBool() && m_bCarryingGhost) || m_iNeoClass == NEO_CLASS_JUGGERNAUT) && GetMoveType() == MOVETYPE_WALK && currentSpeed > speed)
-	{
-		float overSpeed = currentSpeed - speed;
-		absoluteVelocity.NormalizeInPlace();
-		absoluteVelocity *= -overSpeed;
-		ApplyAbsVelocityImpulse(absoluteVelocity);
-	}
 	speed = MAX(speed, 55);
 
 	// Slowdown after jumping
@@ -1770,6 +1758,11 @@ bool C_NEO_Player::IsCarryingGhost(void) const
 	return GetNeoWepWithBits(this, NEO_WEP_GHOST) != NULL;
 }
 
+bool C_NEO_Player::IsObjective(void) const
+{
+	return IsCarryingGhost() || GetClass() == NEO_CLASS_VIP || GetClass() == NEO_CLASS_JUGGERNAUT;
+}
+
 const Vector C_NEO_Player::GetPlayerMins(void) const
 {
 	return VEC_DUCK_HULL_MIN_SCALED(this);

src/game/client/neo/c_neo_player.h

@@ -133,6 +133,7 @@ class C_NEO_Player : public C_HL2MP_Player
 	int GetDisplayedHealth(bool asPercent) const;
 
 	bool IsCarryingGhost(void) const;
+	bool IsObjective(void) const;
 
 	virtual void SetLocalViewAngles( const QAngle &viewAngles ) OVERRIDE
 	{

src/game/server/neo/neo_player.cpp

@@ -685,7 +685,6 @@ void CNEO_Player::CheckLeanButtons()
 	}
 }
 
-extern ConVar neo_ghost_bhopping;
 void CNEO_Player::CalculateSpeed(void)
 {
 	float speed = GetNormSpeed();
@@ -729,17 +728,6 @@ void CNEO_Player::CalculateSpeed(void)
 		speed = MIN(GetFlags() & FL_DUCKING ? NEO_CROUCH_WALK_SPEED : NEO_WALK_SPEED, speed);
 	}
 
-	Vector absoluteVelocity = GetAbsVelocity();
-	absoluteVelocity.z = 0.f;
-	float currentSpeed = absoluteVelocity.Length();
-
-	if (((!neo_ghost_bhopping.GetBool() && m_bCarryingGhost) || m_iNeoClass == NEO_CLASS_JUGGERNAUT) && GetMoveType() == MOVETYPE_WALK && currentSpeed > speed)
-	{
-		float overSpeed = currentSpeed - speed;
-		absoluteVelocity.NormalizeInPlace();
-		absoluteVelocity *= -overSpeed;
-		ApplyAbsVelocityImpulse(absoluteVelocity);
-	}
 	speed = MAX(speed, 55);
 
 	// Slowdown after jumping
@@ -2398,6 +2386,11 @@ bool CNEO_Player::IsCarryingGhost(void) const
 	return GetNeoWepWithBits(this, NEO_WEP_GHOST) != NULL;
 }
 
+bool CNEO_Player::IsObjective(void) const
+{
+	return IsCarryingGhost() || GetClass() == NEO_CLASS_VIP || GetClass() == NEO_CLASS_JUGGERNAUT;
+}
+
 void CNEO_Player::Weapon_Drop( CBaseCombatWeapon *pWeapon,
 	const Vector *pvecTarget, const Vector *pVelocity )
 {

src/game/server/neo/neo_player.h

@@ -126,6 +126,7 @@ class CNEO_Player : public CHL2MP_Player
 	virtual bool	CanHearAndReadChatFrom(CBasePlayer *pPlayer) OVERRIDE;
 
 	bool IsCarryingGhost(void) const;
+	bool IsObjective(void) const;
 
 	void Weapon_AimToggle(CNEOBaseCombatWeapon *pWep, const NeoWeponAimToggleE toggleType);
 

src/game/shared/gamemovement.cpp

@@ -1717,6 +1717,68 @@ void CGameMovement::Friction( void )
  	mv->m_outWishVel -= (1.f-newspeed) * mv->m_vecVelocity;
 }
 
+#ifdef NEO
+ConVar	sv_airfriction("sv_neo_airfriction", "0", FCVAR_NOTIFY | FCVAR_REPLICATED, "Air friction.", true, 0, false, 0);
+ConVar	sv_airfriction_objective("sv_neo_airfriction_objective", "0.5", FCVAR_NOTIFY | FCVAR_REPLICATED, "Air friction for ghost carrier, VIP and juggernaut.", true, 0, false, 0);
+ConVar	sv_airstopspeed("sv_neo_airstopspeed", "0", FCVAR_NOTIFY | FCVAR_REPLICATED, "Minimum stopping speed when in the air.", true, 0, false, 0);
+ConVar	sv_jumpbuffer("sv_neo_jumpbuffer", "0", FCVAR_NOTIFY | FCVAR_REPLICATED | FCVAR_CHEAT, "Allow Quake style jump buffering.", true, 0, true, 1);
+
+//-----------------------------------------------------------------------------
+// Purpose:
+//-----------------------------------------------------------------------------
+void CGameMovement::AirFriction( void )
+{
+	float	speed, newspeed, control;
+	float	friction;
+	float	drop;
+
+	// Friction only works horizontally so zero out the z component
+	float z = mv->m_vecVelocity.z;
+	mv->m_vecVelocity.z = 0;
+	speed = VectorLength( mv->m_vecVelocity );
+
+	// If too slow, return
+	auto neoplayer = ToNEOPlayer(player);
+	float overspeed = speed - neoplayer->GetNormSpeed_WithActiveWepEncumberment();
+	if (overspeed < 0.1f)
+	{
+		// Restore z component
+		mv->m_vecVelocity.z = z;
+		return;
+	}
+
+	drop = 0;
+
+	// apply air friction
+	friction = neoplayer->IsObjective() ? sv_airfriction_objective.GetFloat() : sv_airfriction.GetFloat();
+
+	// Bleed off some speed, but if we have less than the bleed
+	// threshold, bleed the threshold amount.
+	control = (overspeed < sv_airstopspeed.GetFloat()) ? sv_airstopspeed.GetFloat() : overspeed;
+
+	// Add the amount to the drop amount.
+	drop += control*friction*gpGlobals->frametime;
+
+	// scale the velocity
+	newspeed = speed - drop;
+	if (newspeed < 0)
+		newspeed = 0;
+
+	if ( newspeed != speed )
+	{
+		// Determine proportion of old speed we are using.
+		newspeed /= speed;
+		// Adjust velocity according to proportion.
+		VectorScale( mv->m_vecVelocity, newspeed, mv->m_vecVelocity );
+	}
+
+	// Restore z component
+	mv->m_vecVelocity.z = z;
+
+ 	mv->m_outWishVel -= (1.f-newspeed) * mv->m_vecVelocity;
+}
+#endif
+
 //-----------------------------------------------------------------------------
 // Purpose:
 //-----------------------------------------------------------------------------
@@ -2145,6 +2207,12 @@ void CGameMovement::FullWalkMove( )
 			mv->m_vecVelocity[2] = 0.0;
 			Friction();
 		}
+#ifdef NEO
+		else
+		{
+			AirFriction();
+		}
+#endif
 
 		// Make sure velocity is valid.
 		CheckVelocity();
@@ -2442,7 +2510,19 @@ bool CGameMovement::CheckJumpButton( void )
 	// No more effect
  	if (player->GetGroundEntity() == NULL)
 	{
-		mv->m_nOldButtons |= IN_JUMP;
+#ifdef NEO
+		if (sv_jumpbuffer.GetBool())
+		{
+			if (!(mv->m_nOldButtons & IN_JUMP))
+			{
+				mv->m_nButtons &= ~IN_JUMP;
+			}
+		}
+		else
+#endif
+		{
+			mv->m_nOldButtons |= IN_JUMP;
+		}
 		return false;		// in air, so no effect
 	}
 

src/game/shared/gamemovement.h

@@ -102,6 +102,10 @@ class CGameMovement : public IGameMovement
 	// Handles both ground friction and water friction
 	void			Friction( void );
 
+#ifdef NEO
+	void			AirFriction( void );
+#endif
+
 	virtual void	AirAccelerate( Vector& wishdir, float wishspeed, float accel );
 
 	virtual void	AirMove( void );

src/game/shared/neo/neo_player_shared.cpp

@@ -38,7 +38,6 @@ ConVar cl_autoreload_when_empty("cl_autoreload_when_empty", "1", FCVAR_USERINFO
 ConVar neo_aim_hold("neo_aim_hold", "0", FCVAR_USERINFO | FCVAR_ARCHIVE, "Hold to aim as opposed to toggle aim.", true, 0.0f, true, 1.0f);
 #endif
 
-ConVar neo_ghost_bhopping("neo_ghost_bhopping", "0", FCVAR_REPLICATED, "Allow ghost bunnyhopping", true, 0, true, 1);
 ConVar sv_neo_dev_loadout("sv_neo_dev_loadout", "0", FCVAR_CHEAT | FCVAR_REPLICATED | FCVAR_HIDDEN | FCVAR_DONTRECORD, "", true, 0.0f, true, 1.0f);
 
 bool IsAllowedToZoom(CNEOBaseCombatWeapon *pWep)