From b79e3f8904b319771a5f80c4a2a9a0793b84d7a7 Mon Sep 17 00:00:00 2001
From: Player701 <player701@player701.ru>
Date: Fri, 30 Nov 2018 13:22:34 +0300
Subject: [PATCH] - Added a flag to make bouncing objects disappear when
 hitting sky surfaces

---
 src/actor.h                     |  3 ++-
 src/actorinlines.h              |  2 +-
 src/g_levellocals.h             |  8 ++++++++
 src/p_map.cpp                   |  4 ++--
 src/p_mobj.cpp                  | 17 +++++++++++++----
 src/r_defs.h                    |  1 +
 src/scripting/thingdef_data.cpp |  1 +
 7 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/src/actor.h b/src/actor.h
index 8f0a8e9f3..912194f62 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -488,6 +488,7 @@ enum ActorBounceFlag
 	BOUNCE_UseBounceState = 1<<14,	// Use Bounce[.*] states
 	BOUNCE_NotOnShootables = 1<<15,	// do not bounce off shootable actors if we are a projectile. Explode instead.
 	BOUNCE_BounceOnUnrips = 1<<16,	// projectile bounces on actors with DONTRIP
+	BOUNCE_NotOnSky = 1<<17,		// Don't bounce on sky floors / ceilings / walls
 
 	BOUNCE_TypeMask = BOUNCE_Walls | BOUNCE_Floors | BOUNCE_Ceilings | BOUNCE_Actors | BOUNCE_AutoOff | BOUNCE_HereticType | BOUNCE_MBF,
 
@@ -1376,7 +1377,7 @@ public:
 	DVector3 PosRelative(int grp) const;
 	DVector3 PosRelative(const AActor *other) const;
 	DVector3 PosRelative(sector_t *sec) const;
-	DVector3 PosRelative(line_t *line) const;
+	DVector3 PosRelative(const line_t *line) const;
 
 	FVector3 SoundPos() const
 	{
diff --git a/src/actorinlines.h b/src/actorinlines.h
index 10c0ad615..f78163eef 100644
--- a/src/actorinlines.h
+++ b/src/actorinlines.h
@@ -20,7 +20,7 @@ inline DVector3 AActor::PosRelative(sector_t *sec) const
 	return Pos() + level.Displacements.getOffset(Sector->PortalGroup, sec->PortalGroup);
 }
 
-inline DVector3 AActor::PosRelative(line_t *line) const
+inline DVector3 AActor::PosRelative(const line_t *line) const
 {
 	return Pos() + level.Displacements.getOffset(Sector->PortalGroup, line->frontsector->PortalGroup);
 }
diff --git a/src/g_levellocals.h b/src/g_levellocals.h
index 1e3aed96f..fdd9beb15 100644
--- a/src/g_levellocals.h
+++ b/src/g_levellocals.h
@@ -38,6 +38,7 @@
 #include "doomdata.h"
 #include "g_level.h"
 #include "r_defs.h"
+#include "r_sky.h"
 #include "portal.h"
 #include "p_blockmap.h"
 #include "p_local.h"
@@ -318,3 +319,10 @@ inline int line_t::getPortalAlignment() const
 {
 	return portalindex >= level.linePortals.Size() ? 0 : level.linePortals[portalindex].mAlign;
 }
+
+inline bool line_t::hitSkyWall(AActor* mo) const
+{
+	return backsector &&
+		backsector->GetTexture(sector_t::ceiling) == skyflatnum &&
+		mo->Z() >= backsector->ceilingplane.ZatPoint(mo->PosRelative(this));
+}
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 5d248d2db..f463e86c1 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -3551,9 +3551,9 @@ bool FSlide::BounceWall(AActor *mo)
 	}
 	line = bestslideline;
 
-	if (line->special == Line_Horizon)
+	if (line->special == Line_Horizon || (mo->BounceFlags & BOUNCE_NotOnSky) && line->hitSkyWall(mo))
 	{
-		mo->SeeSound = 0;	// it might make a sound otherwise
+		mo->SeeSound = mo->BounceSound = 0;	// it might make a sound otherwise
 		mo->Destroy();
 		return true;
 	}
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index 67290a08e..d9f488725 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -2178,15 +2178,27 @@ bool AActor::FloorBounceMissile (secplane_t &plane)
 		}
 	}
 
+	bool onsky;
+
 	if (plane.fC() < 0)
 	{ // on ceiling
 		if (!(BounceFlags & BOUNCE_Ceilings))
 			return true;
+
+		onsky = ceilingpic == skyflatnum;
 	}
 	else
 	{ // on floor
 		if (!(BounceFlags & BOUNCE_Floors))
 			return true;
+
+		onsky = floorpic == skyflatnum;
+	}
+
+	if (onsky && (BounceFlags & BOUNCE_NotOnSky))
+	{
+		Destroy();
+		return true;
 	}
 
 	// The amount of bounces is limited
@@ -2751,10 +2763,7 @@ double P_XYMovement (AActor *mo, DVector2 scroll)
 explode:
 				// explode a missile
 				bool onsky = false;
-				if (tm.ceilingline &&
-					tm.ceilingline->backsector &&
-					tm.ceilingline->backsector->GetTexture(sector_t::ceiling) == skyflatnum &&
-					mo->Z() >= tm.ceilingline->backsector->ceilingplane.ZatPoint(mo->PosRelative(tm.ceilingline)))
+				if (tm.ceilingline && tm.ceilingline->hitSkyWall(mo))
 				{
 					if (!(mo->flags3 & MF3_SKYEXPLODE))
 					{
diff --git a/src/r_defs.h b/src/r_defs.h
index ad128c4dc..74a2d4942 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -1393,6 +1393,7 @@ struct line_t
 	inline bool isVisualPortal() const;
 	inline line_t *getPortalDestination() const;
 	inline int getPortalAlignment() const;
+	inline bool hitSkyWall(AActor* mo) const;
 
 	int Index() const;
 };
diff --git a/src/scripting/thingdef_data.cpp b/src/scripting/thingdef_data.cpp
index 60200e765..0c572ba3f 100644
--- a/src/scripting/thingdef_data.cpp
+++ b/src/scripting/thingdef_data.cpp
@@ -360,6 +360,7 @@ static FFlagDef ActorFlagDefs[]=
 	DEFINE_FLAG2(BOUNCE_UseBounceState, USEBOUNCESTATE, AActor, BounceFlags),
 	DEFINE_FLAG2(BOUNCE_NotOnShootables, DONTBOUNCEONSHOOTABLES, AActor, BounceFlags),
 	DEFINE_FLAG2(BOUNCE_BounceOnUnrips, BOUNCEONUNRIPPABLES, AActor, BounceFlags),
+	DEFINE_FLAG2(BOUNCE_NotOnSky, DONTBOUNCEONSKY, AActor, BounceFlags),
 };
 
 // These won't be accessible through bitfield variables