From 211a28692b6220aafa335a256049290fcbc00aa1 Mon Sep 17 00:00:00 2001
From: Marco Hladik <marco@icculus.org>
Date: Fri, 17 Sep 2021 00:41:58 +0200
Subject: [PATCH] CBaseMonster: Add FALLING flag, and FallNoise() method so
 monsters/npcs can specify what to do/play when they start falling.

---
 src/gs-entbase/server/basemonster.h  |  4 +++-
 src/gs-entbase/server/basemonster.qc | 15 ++++++++++++++-
 src/gs-entbase/server/basenpc.h      |  1 -
 src/gs-entbase/server/basenpc.qc     | 10 +++++++---
 4 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/src/gs-entbase/server/basemonster.h b/src/gs-entbase/server/basemonster.h
index d8b40424..ae745ff4 100644
--- a/src/gs-entbase/server/basemonster.h
+++ b/src/gs-entbase/server/basemonster.h
@@ -36,7 +36,8 @@ typedef enumflags
 	MSF_WAITFORSCRIPT,
 	MSF_PREDISASTER,
 	MSF_FADECORPSE,
-	MSF_MULTIPLAYER
+	MSF_MULTIPLAYER,
+	MSF_FALLING
 } monsterFlag_t;
 
 /* movement states */
@@ -139,6 +140,7 @@ class CBaseMonster:CBaseEntity
 	virtual void(void) Death;
 	virtual void(void) Physics;
 	virtual void(void) IdleNoise;
+	virtual void(void) FallNoise;
 	virtual void(void) Gib;
 	virtual void(string) Sound;
 	virtual void(string, string) SpawnKey;
diff --git a/src/gs-entbase/server/basemonster.qc b/src/gs-entbase/server/basemonster.qc
index 497c8132..643b2c12 100644
--- a/src/gs-entbase/server/basemonster.qc
+++ b/src/gs-entbase/server/basemonster.qc
@@ -56,10 +56,14 @@ CBaseMonster::Gib(void)
 	Hide();
 }
 
+void
+CBaseMonster::FallNoise(void)
+{
+}
+
 void
 CBaseMonster::IdleNoise(void)
 {
-
 }
 
 int
@@ -462,6 +466,15 @@ CBaseMonster::Physics(void)
 		}
 	}
 
+	if (velocity[2] < -100) {
+		if (!(m_iFlags & MSF_FALLING))
+			FallNoise();
+
+		m_iFlags |= MSF_FALLING;
+	} else {
+		m_iFlags &= ~MSF_FALLING;
+	}
+
 	/* support for think/nextthink */
 	if (think && nextthink > 0.0f) {
 		if (nextthink < time) {
diff --git a/src/gs-entbase/server/basenpc.h b/src/gs-entbase/server/basenpc.h
index 42916786..b6dbf984 100644
--- a/src/gs-entbase/server/basenpc.h
+++ b/src/gs-entbase/server/basenpc.h
@@ -24,7 +24,6 @@ enumflags
 	MONSTER_USED,
 	MONSTER_FEAR,
 	MONSTER_METPLAYER,
-	MONSTER_FALLING,
 	MONSTER_CANFOLLOW
 };
 
diff --git a/src/gs-entbase/server/basenpc.qc b/src/gs-entbase/server/basenpc.qc
index dc1491b2..aa764792 100644
--- a/src/gs-entbase/server/basenpc.qc
+++ b/src/gs-entbase/server/basenpc.qc
@@ -416,10 +416,14 @@ CBaseNPC::Physics(void)
 		SetOrigin(origin);
 	}
 
-	if (!(flags & FL_ONGROUND) && velocity[2] < -100) {
-		m_iFlags |= MONSTER_FALLING;
+	if (velocity[2] < -100) {
+		if (!(m_iFlags & MSF_FALLING)) {
+			FallNoise();
+		}
+
+		m_iFlags |= MSF_FALLING;
 	} else {
-		m_iFlags &= ~MONSTER_FALLING;
+		m_iFlags &= ~MSF_FALLING;
 	}
 
 	/* support for think/nextthink */