From b2110d035420085cb6042e80e863d86f554f4188 Mon Sep 17 00:00:00 2001
From: Blixibon <acj3017@gmail.com>
Date: Mon, 21 Nov 2022 00:51:54 -0600
Subject: [PATCH] Added NPC PVS checking for point_cameras

---
 sp/src/game/server/ai_basenpc.cpp   |  7 ++++
 sp/src/game/server/point_camera.cpp | 52 +++++++++++++++++++++++++++++
 sp/src/game/server/point_camera.h   |  5 +++
 3 files changed, 64 insertions(+)

diff --git a/sp/src/game/server/ai_basenpc.cpp b/sp/src/game/server/ai_basenpc.cpp
index c503a09c..299aa5c4 100644
--- a/sp/src/game/server/ai_basenpc.cpp
+++ b/sp/src/game/server/ai_basenpc.cpp
@@ -98,6 +98,7 @@
 #ifdef MAPBASE
 #include "mapbase/matchers.h"
 #include "items.h"
+#include "point_camera.h"
 #endif
 
 #ifdef MAPBASE_VSCRIPT
@@ -4301,6 +4302,12 @@ bool CAI_BaseNPC::CheckPVSCondition()
 {
 	bool bInPVS = ( UTIL_FindClientInPVS( edict() ) != NULL ) || (UTIL_ClientPVSIsExpanded() && UTIL_FindClientInVisibilityPVS( edict() ));
 
+#ifdef MAPBASE
+	// We can be in a player's PVS if there is an active point_camera nearby (fixes issues with choreo)
+	if (!bInPVS && UTIL_FindRTCameraInEntityPVS( edict() ))
+		bInPVS = true;
+#endif
+
 	if ( bInPVS )
 		SetCondition( COND_IN_PVS );
 	else
diff --git a/sp/src/game/server/point_camera.cpp b/sp/src/game/server/point_camera.cpp
index 626bc61b..72a40b26 100644
--- a/sp/src/game/server/point_camera.cpp
+++ b/sp/src/game/server/point_camera.cpp
@@ -28,6 +28,58 @@ CPointCamera* GetPointCameraList()
 	return g_PointCameraList.m_pClassList;
 }
 
+#ifdef MAPBASE
+//-----------------------------------------------------------------------------
+// Purpose: Returns true if a camera is in the PVS of the specified entity
+//-----------------------------------------------------------------------------
+edict_t *UTIL_FindRTCameraInEntityPVS( edict_t *pEdict )
+{
+	CBaseEntity *pe = GetContainingEntity( pEdict );
+	if ( !pe )
+		return NULL;
+	
+	bool			bGotPVS = false;
+	Vector			org;
+	static byte		pvs[ MAX_MAP_CLUSTERS/8 ];
+	static int		pvssize = sizeof( pvs );
+
+	for ( CPointCamera *pCameraEnt = GetPointCameraList(); pCameraEnt != NULL; pCameraEnt = pCameraEnt->m_pNext )
+	{
+		if (!pCameraEnt->IsActive())
+			continue;
+
+		if (!bGotPVS)
+		{
+			// Getting the PVS during the loop like this makes sure we only get the PVS if there's actually an active camera in the level
+			org = pe->EyePosition();
+			int clusterIndex = engine->GetClusterForOrigin( org );
+			Assert( clusterIndex >= 0 );
+			engine->GetPVSForCluster( clusterIndex, pvssize, pvs );
+			bGotPVS = true;
+		}
+
+		Vector vecCameraEye = pCameraEnt->EyePosition();
+
+		Vector vecCameraDirection;
+		pCameraEnt->GetVectors( &vecCameraDirection, NULL, NULL );
+
+		Vector los = (org - vecCameraEye);
+		float flDot = DotProduct( los, vecCameraDirection );
+
+		// Make sure we're in the camera's FOV before checking PVS
+		if ( flDot <= cos( DEG2RAD( pCameraEnt->GetFOV() / 2 ) ) )
+			continue;
+
+		if ( engine->CheckOriginInPVS( vecCameraEye, pvs, pvssize ) )
+		{
+			return pCameraEnt->edict();
+		}
+	}
+
+	return NULL;
+}
+#endif
+
 // These are already built into CBaseEntity
 //	DEFINE_KEYFIELD( m_iName, FIELD_STRING, "targetname" ),
 //	DEFINE_KEYFIELD( m_iParent, FIELD_STRING, "parentname" ),
diff --git a/sp/src/game/server/point_camera.h b/sp/src/game/server/point_camera.h
index c669ab82..9cb7d3c4 100644
--- a/sp/src/game/server/point_camera.h
+++ b/sp/src/game/server/point_camera.h
@@ -42,6 +42,7 @@ public:
 	void InputSetRenderTarget( inputdata_t &inputdata ) { m_iszRenderTarget = inputdata.value.StringID(); }
 
 	float GetFOV() const { return m_FOV; }
+	bool IsActive() const { return m_bIsOn; }
 #endif
 
 private:
@@ -117,4 +118,8 @@ private:
 #endif
 
 CPointCamera *GetPointCameraList();
+
+#ifdef MAPBASE
+edict_t *UTIL_FindRTCameraInEntityPVS( edict_t *pEdict );
+#endif
 #endif // CAMERA_H