diff --git a/src/p_ceiling.cpp b/src/p_ceiling.cpp
index 5ed7dd3720..4199ccb64b 100644
--- a/src/p_ceiling.cpp
+++ b/src/p_ceiling.cpp
@@ -257,7 +257,7 @@ bool P_CreateCeiling(sector_t *sec, DCeiling::ECeiling type, line_t *line, int t
 	case DCeiling::ceilCrushRaiseAndStay:
 		ceiling->m_TopHeight = sec->ceilingplane.fD();
 	case DCeiling::ceilLowerAndCrush:
-		targheight = sec->FindHighestFloorPoint (&spot);
+		targheight = FindHighestFloorPoint (sec, &spot);
 		targheight += height;
 		ceiling->m_BottomHeight = sec->ceilingplane.PointToDist (spot, targheight);
 		ceiling->m_Direction = -1;
@@ -350,13 +350,13 @@ bool P_CreateCeiling(sector_t *sec, DCeiling::ECeiling type, line_t *line, int t
 		break;
 
 	case DCeiling::ceilLowerToFloor:
-		targheight = sec->FindHighestFloorPoint (&spot) + height;
+		targheight = FindHighestFloorPoint (sec, &spot) + height;
 		ceiling->m_BottomHeight = sec->ceilingplane.PointToDist (spot, targheight);
 		ceiling->m_Direction = -1;
 		break;
 
 	case DCeiling::ceilRaiseToFloor:	// [RH] What's this for?
-		targheight = sec->FindHighestFloorPoint (&spot) + height;
+		targheight = FindHighestFloorPoint (sec, &spot) + height;
 		ceiling->m_TopHeight = sec->ceilingplane.PointToDist (spot, targheight);
 		ceiling->m_Direction = 1;
 		break;
diff --git a/src/p_doors.cpp b/src/p_doors.cpp
index 8bbbabf52b..fa08f32598 100644
--- a/src/p_doors.cpp
+++ b/src/p_doors.cpp
@@ -388,7 +388,7 @@ DDoor::DDoor (sector_t *sec, EVlDoor type, double speed, int delay, int lightTag
 	case doorWaitClose:
 		m_Direction = 0;
 		m_Type = DDoor::doorRaise;
-		height = sec->FindHighestFloorPoint (&m_BotSpot);
+		height = FindHighestFloorPoint (sec, &m_BotSpot);
 		m_BotDist = sec->ceilingplane.PointToDist (m_BotSpot, height);
 		m_OldFloorDist = sec->floorplane.fD();
 		m_TopDist = sec->ceilingplane.fD();
@@ -399,7 +399,7 @@ DDoor::DDoor (sector_t *sec, EVlDoor type, double speed, int delay, int lightTag
 	if (!m_Sector->floordata || !m_Sector->floordata->IsKindOf(RUNTIME_CLASS(DPlat)) ||
 		!(barrier_cast<DPlat*>(m_Sector->floordata))->IsLift())
 	{
-		height = sec->FindHighestFloorPoint (&m_BotSpot);
+		height = FindHighestFloorPoint (sec, &m_BotSpot);
 		m_BotDist = sec->ceilingplane.PointToDist (m_BotSpot, height);
 	}
 	else
diff --git a/src/p_floor.cpp b/src/p_floor.cpp
index 97d7c16be7..4067071aef 100644
--- a/src/p_floor.cpp
+++ b/src/p_floor.cpp
@@ -338,7 +338,7 @@ bool P_CreateFloor(sector_t *sec, DFloor::EFloor floortype, line_t *line,
 		break;
 
 	case DFloor::floorMoveToValue:
-		sec->FindHighestFloorPoint(&spot);
+		FindHighestFloorPoint(sec, &spot);
 		floor->m_FloorDestDist = sec->floorplane.PointToDist(spot, height);
 		floor->m_Direction = (floor->m_FloorDestDist > sec->floorplane.fD()) ? -1 : 1;
 		break;
@@ -829,7 +829,7 @@ bool EV_DoDonut (int tag, line_t *line, double pillarspeed, double slimespeed)
 			floor->m_Instant = false;
 			floor->m_Texture = s3->GetTexture(sector_t::floor);
 			floor->m_NewSpecial = {};
-			height = s3->FindHighestFloorPoint (&spot);
+			height = FindHighestFloorPoint (s3, &spot);
 			floor->m_FloorDestDist = s2->floorplane.PointToDist (spot, height);
 			floor->StartFloorSound ();
 			
@@ -842,7 +842,7 @@ bool EV_DoDonut (int tag, line_t *line, double pillarspeed, double slimespeed)
 			floor->m_Sector = s1;
 			floor->m_Speed = pillarspeed;
 			floor->m_Instant = false;
-			height = s3->FindHighestFloorPoint (&spot);
+			height = FindHighestFloorPoint (s3, &spot);
 			floor->m_FloorDestDist = s1->floorplane.PointToDist (spot, height);
 			floor->StartFloorSound ();
 			break;
diff --git a/src/p_lights.cpp b/src/p_lights.cpp
index 86dfbb8cb5..d2f743ad9a 100644
--- a/src/p_lights.cpp
+++ b/src/p_lights.cpp
@@ -246,7 +246,7 @@ DFireFlicker::DFireFlicker (sector_t *sector)
 	: DLighting (sector)
 {
 	m_MaxLight = sector->lightlevel;
-	m_MinLight = sector_t::ClampLight(sector->FindMinSurroundingLight(sector->lightlevel) + 16);
+	m_MinLight = sector_t::ClampLight(FindMinSurroundingLight(sector, sector->lightlevel) + 16);
 	m_Count = 4;
 }
 
@@ -391,7 +391,7 @@ DLightFlash::DLightFlash (sector_t *sector)
 {
 	// Find light levels like Doom.
 	m_MaxLight = sector->lightlevel;
-	m_MinLight = sector->FindMinSurroundingLight (sector->lightlevel);
+	m_MinLight = FindMinSurroundingLight (sector, sector->lightlevel);
 	m_MaxTime = 64;
 	m_MinTime = 7;
 	m_Count = (pr_lightflash() & m_MaxTime) + 1;
@@ -483,7 +483,7 @@ DStrobe::DStrobe (sector_t *sector, int utics, int ltics, bool inSync)
 	m_BrightTime = utics;
 
 	m_MaxLight = sector->lightlevel;
-	m_MinLight = sector->FindMinSurroundingLight (sector->lightlevel);
+	m_MinLight = FindMinSurroundingLight (sector, sector->lightlevel);
 
 	if (m_MinLight == m_MaxLight)
 		m_MinLight = 0;
@@ -729,7 +729,7 @@ void DGlow::Tick ()
 DGlow::DGlow (sector_t *sector)
 	: DLighting (sector)
 {
-	m_MinLight = sector->FindMinSurroundingLight (sector->lightlevel);
+	m_MinLight = FindMinSurroundingLight (sector, sector->lightlevel);
 	m_MaxLight = sector->lightlevel;
 	m_Direction = -1;
 }
diff --git a/src/p_sectors.cpp b/src/p_sectors.cpp
index 19a0d172d4..b896ed08ed 100644
--- a/src/p_sectors.cpp
+++ b/src/p_sectors.cpp
@@ -595,13 +595,13 @@ sector_t *FindModelCeilingSector (sector_t *sect, double floordestheight)
 //
 // Find minimum light from an adjacent sector
 //
-int sector_t::FindMinSurroundingLight (int min) const
+int FindMinSurroundingLight (const sector_t *sector, int min)
 {
 	sector_t*	check;
 		
-	for (auto line : Lines)
+	for (auto line : sector->Lines)
 	{
-		if (NULL != (check = getNextSector (line, this)) &&
+		if (NULL != (check = getNextSector (line, sector)) &&
 			check->lightlevel < min)
 		{
 			min = check->lightlevel;
@@ -613,38 +613,38 @@ int sector_t::FindMinSurroundingLight (int min) const
 //
 // Find the highest point on the floor of the sector
 //
-double sector_t::FindHighestFloorPoint (vertex_t **v) const
+double FindHighestFloorPoint (const sector_t *sector, vertex_t **v)
 {
 	double height = -FLT_MAX;
 	double probeheight;
 	vertex_t *spot = NULL;
 
-	if (!floorplane.isSlope())
+	if (!sector->floorplane.isSlope())
 	{
 		if (v != NULL)
 		{
-			if (Lines.Size() == 0) *v = &level.vertexes[0];
-			else *v = Lines[0]->v1;
+			if (sector->Lines.Size() == 0) *v = &level.vertexes[0];
+			else *v = sector->Lines[0]->v1;
 		}
-		return -floorplane.fD();
+		return -sector->floorplane.fD();
 	}
 
-	for (auto line : Lines)
+	for (auto line : sector->Lines)
 	{
-		probeheight = floorplane.ZatPoint(line->v1);
+		probeheight = sector->floorplane.ZatPoint(line->v1);
 		if (probeheight > height)
 		{
 			height = probeheight;
 			spot = line->v1;
 		}
-		probeheight = floorplane.ZatPoint(line->v2);
+		probeheight = sector->floorplane.ZatPoint(line->v2);
 		if (probeheight > height)
 		{
 			height = probeheight;
 			spot = line->v2;
 		}
 	}
-	if (v != NULL)
+	if (v != nullptr)
 		*v = spot;
 	return height;
 }
diff --git a/src/r_defs.h b/src/r_defs.h
index c0857b7c78..acf9b0f933 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -623,9 +623,7 @@ public:
 
 	bool IsLinked(sector_t *other, bool ceiling) const;
 
-	int FindMinSurroundingLight (int max) const;
 	sector_t *NextSpecialSector (int type, sector_t *prev) const;		// [RH]
-	double FindHighestFloorPoint(vertex_t **v) const;
 	void RemoveForceField();
 	int Index() const;
 
@@ -1598,6 +1596,8 @@ double FindLowestCeilingSurrounding(const sector_t *sec, vertex_t **v);			// jff
 double FindHighestCeilingSurrounding(const sector_t *sec, vertex_t **v);			// jff 2/04/98
 double FindNextLowestCeiling(const sector_t *sec, vertex_t **v);					// jff 2/04/98
 double FindNextHighestCeiling(const sector_t *sec, vertex_t **v);					// jff 2/04/98
+int FindMinSurroundingLight (const sector_t *sec, int max);
+double FindHighestFloorPoint(const sector_t *sec, vertex_t **v);
 
 double FindShortestTextureAround(sector_t *sector);					// jff 2/04/98
 double FindShortestUpperAround(sector_t *sector);					// jff 2/04/98
diff --git a/src/scripting/vmthunks.cpp b/src/scripting/vmthunks.cpp
index 8e1125bef0..3b9a549474 100644
--- a/src/scripting/vmthunks.cpp
+++ b/src/scripting/vmthunks.cpp
@@ -110,19 +110,19 @@ DEFINE_ACTION_FUNCTION_NATIVE(_Sector, FindHighestCeilingSurrounding, FindHighes
 }
 
 
-DEFINE_ACTION_FUNCTION(_Sector, FindMinSurroundingLight)
+DEFINE_ACTION_FUNCTION_NATIVE(_Sector, FindMinSurroundingLight, FindMinSurroundingLight)
 {
 	PARAM_SELF_STRUCT_PROLOGUE(sector_t);
 	PARAM_INT(min);
-	auto h = self->FindMinSurroundingLight(min);
+	auto h = FindMinSurroundingLight(self, min);
 	ACTION_RETURN_INT(h);
 }
 
-DEFINE_ACTION_FUNCTION(_Sector, FindHighestFloorPoint)
+DEFINE_ACTION_FUNCTION_NATIVE(_Sector, FindHighestFloorPoint, FindHighestFloorPoint)
 {
 	PARAM_SELF_STRUCT_PROLOGUE(sector_t);
 	vertex_t *v;
-	double h = self->FindHighestFloorPoint(&v);
+	double h = FindHighestFloorPoint(self, &v);
 	if (numret > 0) ret[0].SetFloat(h);
 	if (numret > 1) ret[1].SetPointer(v);
 	return numret;
@@ -498,7 +498,7 @@ DEFINE_ACTION_FUNCTION_NATIVE(_Sector, RemoveForceField, RemoveForceField)
 	 self->SetYScale(pos, o);
  }
 
- DEFINE_ACTION_FUNCTION(_Sector, SetYScale)
+ DEFINE_ACTION_FUNCTION_NATIVE(_Sector, SetYScale, SetYScale)
  {
 	 PARAM_SELF_STRUCT_PROLOGUE(sector_t);
 	 PARAM_INT(pos);