Grenade/alt-fire item dropping for metrocops and player companions

sp/src/game/server/mapbase/ai_grenade.cpp

@@ -11,3 +11,5 @@
 
 int COMBINE_AE_BEGIN_ALTFIRE;
 int COMBINE_AE_ALTFIRE;
+
+ConVar ai_grenade_always_drop( "ai_grenade_always_drop", "0", FCVAR_NONE, "Causes non-Combine grenade user NPCs to be allowed to drop grenades, alt-fire items, etc. *IF* the keyvalue has not already been set in Hammer. This is useful for debugging purposes or if a mod which was developed before this feature was introduced wants its NPCs to drop grenades and beyond without recompiling all of the maps." );

sp/src/game/server/mapbase/ai_grenade.h

@@ -19,6 +19,9 @@
 #include "basegrenade_shared.h"
 #include "ai_squad.h"
 #include "GlobalStrings.h"
+#include "gameweaponmanager.h"
+#include "hl2_gamerules.h"
+#include "weapon_physcannon.h"
 
 #define COMBINE_AE_GREN_TOSS		( 7 )
 
@@ -36,6 +39,7 @@
 	DEFINE_FIELD( m_flNextAltFireTime, FIELD_TIME ),	\
 	DEFINE_FIELD( m_vecAltFireTarget, FIELD_VECTOR ),	\
 	DEFINE_FIELD( m_vecTossVelocity, FIELD_VECTOR ),	\
+	DEFINE_FIELD( m_iLastAnimEventHandled, FIELD_INTEGER ),	\
 	DEFINE_INPUTFUNC( FIELD_STRING,	"ThrowGrenadeAtTarget",	InputThrowGrenadeAtTarget ),	\
 	DEFINE_INPUTFUNC( FIELD_INTEGER,	"SetGrenades",	InputSetGrenades ),	\
 	DEFINE_INPUTFUNC( FIELD_INTEGER,	"AddGrenades",	InputAddGrenades ),	\
@@ -61,12 +65,22 @@
 extern int COMBINE_AE_BEGIN_ALTFIRE;
 extern int COMBINE_AE_ALTFIRE;
 
+extern ConVar ai_grenade_always_drop;
+
 enum eGrenadeCapabilities
 {
 	GRENCAP_GRENADE = (1 << 0),
 	GRENCAP_ALTFIRE = (1 << 1),
 };
 
+// What grenade/item types NPCs are capable of dropping
+enum eGrenadeDropCapabilities
+{
+	GRENDROPCAP_GRENADE = (1 << 0),
+	GRENDROPCAP_ALTFIRE = (1 << 1),
+	GRENDROPCAP_INTERRUPTED = (1 << 2), // Drops grenades when interrupted mid-animation
+};
+
 //-----------------------------------------------------------------------------
 // Other classes can use this and access some CAI_GrenadeUser functions.
 //-----------------------------------------------------------------------------
@@ -102,7 +116,8 @@ public:
 			m_OnOutOfGrenades.Set( pLastGrenade, pLastGrenade, this );
 	}
 
-	virtual bool	IsAltFireCapable() { return false; }
+	// Use secondary ammo as a way of checking if this is a weapon which can be alt-fired (e.g. AR2 or SMG)
+	virtual bool	IsAltFireCapable() { return (GetActiveWeapon() && GetActiveWeapon()->UsesSecondaryAmmo()); }
 	virtual bool	IsGrenadeCapable() { return true; }
 	inline bool		HasGrenades() { return m_iNumGrenades > 0; }
 
@@ -113,6 +128,7 @@ public:
 	virtual void DelayGrenadeCheck( float delay ) { m_flNextGrenadeCheck = gpGlobals->curtime + delay; }
 
 	void 			HandleAnimEvent( animevent_t *pEvent );
+	void			SetActivity( Activity NewActivity );
 
 	// Soldiers use "lefthand", cops use "LHand", and citizens use "anim_attachment_LH"
 	virtual const char*		GetGrenadeAttachment() { return "anim_attachment_LH"; }
@@ -131,6 +147,12 @@ public:
 	// For OnThrowGrenade + point_entity_replace, see grenade_frag.cpp
 	bool			UsingOnThrowGrenade() { return m_OnThrowGrenade.NumberOfElements() > 0; }
 
+	// For dropping grenades and beyond
+	void			DropGrenadeItemsOnDeath( const CTakeDamageInfo &info, CBasePlayer *pPlayer );
+	virtual bool	ShouldDropGrenades() { return HasGrenades(); }
+	virtual bool	ShouldDropInterruptedGrenades() { return true; }
+	virtual bool	ShouldDropAltFire() { return HasGrenades(); }
+
 protected:
 
 	void			StartTask_FaceAltFireTarget( const Task_t *pTask );
@@ -151,6 +173,9 @@ protected: // We can't have any private saved variables because only derived cla
 	Vector			m_vecAltFireTarget;
 	Vector			m_vecTossVelocity;
 
+	// CNPC_Combine port for determining if we tossed a grenade
+	int				m_iLastAnimEventHandled;
+
 	COutputEHANDLE	m_OnThrowGrenade;
 	COutputEHANDLE	m_OnOutOfGrenades;
 };
@@ -166,6 +191,8 @@ void CAI_GrenadeUser<BASE_NPC>::HandleAnimEvent( animevent_t *pEvent )
 		if (this->GetActiveWeapon())
 			this->GetActiveWeapon()->WeaponSound( SPECIAL1 );
 
+		m_iLastAnimEventHandled = pEvent->event;
+
 		//SpeakIfAllowed( TLK_CMB_THROWGRENADE, "altfire:1" );
 		return;
 	}
@@ -185,6 +212,8 @@ void CAI_GrenadeUser<BASE_NPC>::HandleAnimEvent( animevent_t *pEvent )
 
 		AddGrenades(-1);
 
+		m_iLastAnimEventHandled = pEvent->event;
+
 		return;
 	}
 
@@ -221,12 +250,25 @@ void CAI_GrenadeUser<BASE_NPC>::HandleAnimEvent( animevent_t *pEvent )
 
 		// wait six seconds before even looking again to see if a grenade can be thrown.
 		m_flNextGrenadeCheck = gpGlobals->curtime + 6;
+
+		m_iLastAnimEventHandled = pEvent->event;
+
 		return;
 	}
 
 	BaseClass::HandleAnimEvent( pEvent );
 }
 
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+template <class BASE_NPC>
+void CAI_GrenadeUser<BASE_NPC>::SetActivity( Activity NewActivity )
+{
+	BaseClass::SetActivity( NewActivity );
+
+	m_iLastAnimEventHandled = -1;
+}
+
 //-----------------------------------------------------------------------------
 // Purpose: Force the combine soldier to throw a grenade at the target
 //			If I'm a combine elite, fire my combine ball at the target instead.
@@ -534,6 +576,105 @@ void CAI_GrenadeUser<BASE_NPC>::ClearAttackConditions()
 	}
 }
 
+//-----------------------------------------------------------------------------
+// Purpose: Drops grenades and alt-fire items on death. Based on code from npc_combines.cpp and npc_combine.cpp
+//-----------------------------------------------------------------------------
+template <class BASE_NPC>
+void CAI_GrenadeUser<BASE_NPC>::DropGrenadeItemsOnDeath( const CTakeDamageInfo &info, CBasePlayer *pPlayer )
+{
+	// Elites drop alt-fire ammo, so long as they weren't killed by dissolving.
+	if( IsAltFireCapable() && ShouldDropAltFire() )
+	{
+		CBaseEntity *pItem;
+		if (this->GetActiveWeapon() && FClassnameIs( this->GetActiveWeapon(), "weapon_smg1" ))
+			pItem = this->DropItem( "item_ammo_smg1_grenade", WorldSpaceCenter()+RandomVector(-4,4), RandomAngle(0,360) );
+		else
+			pItem = this->DropItem( "item_ammo_ar2_altfire", WorldSpaceCenter() + RandomVector( -4, 4 ), RandomAngle( 0, 360 ) );
+
+		if ( pItem )
+		{
+			IPhysicsObject *pObj = pItem->VPhysicsGetObject();
+
+			if ( pObj )
+			{
+				Vector			vel		= RandomVector( -64.0f, 64.0f );
+				AngularImpulse	angImp	= RandomAngularImpulse( -300.0f, 300.0f );
+
+				vel[2] = 0.0f;
+				pObj->AddVelocity( &vel, &angImp );
+			}
+
+			if( info.GetDamageType() & DMG_DISSOLVE )
+			{
+				CBaseAnimating *pAnimating = dynamic_cast<CBaseAnimating*>(pItem);
+
+				if( pAnimating )
+				{
+					pAnimating->Dissolve( NULL, gpGlobals->curtime, false, ENTITY_DISSOLVE_NORMAL );
+				}
+			}
+			else
+			{
+				WeaponManager_AddManaged( pItem );
+			}
+		}
+	}
+	
+	if ( IsGrenadeCapable() )
+	{
+		if ( ShouldDropGrenades() )
+		{
+			CHalfLife2 *pHL2GameRules = static_cast<CHalfLife2 *>(g_pGameRules);
+
+			// Attempt to drop a grenade
+			if ( pHL2GameRules->NPC_ShouldDropGrenade( pPlayer ) )
+			{
+				this->DropItem( "weapon_frag", WorldSpaceCenter()+RandomVector(-4,4), RandomAngle(0,360) );
+				pHL2GameRules->NPC_DroppedGrenade();
+			}
+		}
+
+		// if I was killed before I could finish throwing my grenade, drop
+		// a grenade item that the player can retrieve.
+		if (GetActivity() == ACT_RANGE_ATTACK2 && ShouldDropInterruptedGrenades())
+		{
+			if( m_iLastAnimEventHandled != COMBINE_AE_GREN_TOSS )
+			{
+				// Drop the grenade as an item.
+				Vector vecStart;
+				this->GetAttachment( GetGrenadeAttachment(), vecStart );
+
+				CBaseEntity *pItem = DropItem( "weapon_frag", vecStart, RandomAngle(0,360) );
+
+				if ( pItem )
+				{
+					IPhysicsObject *pObj = pItem->VPhysicsGetObject();
+
+					if ( pObj )
+					{
+						Vector			vel;
+						vel.x = random->RandomFloat( -100.0f, 100.0f );
+						vel.y = random->RandomFloat( -100.0f, 100.0f );
+						vel.z = random->RandomFloat( 800.0f, 1200.0f );
+						AngularImpulse	angImp	= RandomAngularImpulse( -300.0f, 300.0f );
+
+						vel[2] = 0.0f;
+						pObj->AddVelocity( &vel, &angImp );
+					}
+
+					// In the Citadel we need to dissolve this
+					if ( PlayerHasMegaPhysCannon() && GlobalEntity_GetCounter("super_phys_gun") != 1 )
+					{
+						CBaseCombatWeapon *pWeapon = static_cast<CBaseCombatWeapon *>(pItem);
+
+						pWeapon->Dissolve( NULL, gpGlobals->curtime, false, ENTITY_DISSOLVE_NORMAL );
+					}
+				}
+			}
+		}
+	}
+}
+
 //-----------------------------------------------------------------------------
 // Purpose: Task helpers
 //-----------------------------------------------------------------------------