Add per-tier sidedef light levels to UDMF maps

specs/udmf_zdoom.txt

@@ -156,31 +156,40 @@ Note: All <bool> fields default to false unless mentioned otherwise.
 
    sidedef
    {
-      scalex_top = <float>;         // X scale for upper texture, Default = 1.0.
+      scalex_top = <float>;            // X scale for upper texture, Default = 1.0.
-      scaley_top = <float>;         // y scale for upper texture, Default = 1.0.
+      scaley_top = <float>;            // Y scale for upper texture, Default = 1.0.
-      scalex_mid = <float>;         // X scale for mid texture, Default = 1.0.
+      scalex_mid = <float>;            // X scale for mid texture, Default = 1.0.
-      scaley_mid = <float>;         // y scale for mid texture, Default = 1.0.
+      scaley_mid = <float>;            // Y scale for mid texture, Default = 1.0.
-      scalex_bottom = <float>;      // X scale for lower texture, Default = 1.0.
+      scalex_bottom = <float>;         // X scale for lower texture, Default = 1.0.
-      scaley_bottom = <float>;      // y scale for lower texture, Default = 1.0.
+      scaley_bottom = <float>;         // Y scale for lower texture, Default = 1.0.
-      offsetx_top = <float>;        // X offset for upper texture, Default = 0.0.
+      offsetx_top = <float>;           // X offset for upper texture, Default = 0.0.
-      offsety_top = <float>;        // y offset for upper texture, Default = 0.0.
+      offsety_top = <float>;           // Y offset for upper texture, Default = 0.0.
-      offsetx_mid = <float>;        // X offset for mid texture, Default = 0.0.
+      offsetx_mid = <float>;           // X offset for mid texture, Default = 0.0.
-      offsety_mid = <float>;        // y offset for mid texture, Default = 0.0.
+      offsety_mid = <float>;           // Y offset for mid texture, Default = 0.0.
-      offsetx_bottom = <float>;     // X offset for lower texture, Default = 0.0.
+      offsetx_bottom = <float>;        // X offset for lower texture, Default = 0.0.
-      offsety_bottom = <float>;     // y offset for lower texture, Default = 0.0.
+      offsety_bottom = <float>;        // Y offset for lower texture, Default = 0.0.
-                                    // When global texture offsets are used they will
+                                       // When global texture offsets are used they will
-                                    // be added on top of these values.
+                                       // be added on top of these values.
-      light = <integer>;            // This side's light level. Default is 0.
+      light = <integer>;               // This side's light level. Default is 0.
-      lightabsolute = <bool>;       // true = 'light' is an absolute value. Default is 
+      lightabsolute = <bool>;          // true = 'light' is an absolute value. Default is 
-                                    // relative to the owning sector's light level.
+                                       // relative to the owning sector's light level.
-      lightfog = <bool>;            // true = This side's relative lighting is used even in
+      light_top = <integer>;           // This side's top tier light level. Default is 0.
-                                    // foggy sectors. Default is to disable relative
+      lightabsolute_top = <bool>;      // true = 'light_top' is an absolute value. Default is
-                                    // lighting in foggy sectors.
+                                       // relative to the sidedef's resulting light level.
-      nofakecontrast = <bool>;      // Disables use of fake contrast on this sidedef.
+      light_mid = <integer>;           // This side's mid tier light level. Default is 0.
-      smoothlighting = <bool>;      // Use smooth fake contrast.
+      lightabsolute_mid = <bool>;      // true = 'light_mid' is an absolute value. Default is
-      clipmidtex = <bool>;          // Side's mid textures are clipped to floor and ceiling.
+                                       // relative to the sidedef's resulting light level.
-      wrapmidtex = <bool>;          // Side's mid textures are wrapped.
+      light_bottom = <integer>;        // This side's bottom tier light level. Default is 0.
-      nodecals = <bool>;            // Disables decals on the sidedef.
+      lightabsolute_bottom = <bool>;   // true = 'light_bottom' is an absolute value. Default is
+                                       // relative to the sidedef's resulting light level.
+      lightfog = <bool>;               // true = This side's relative lighting is used even in
+                                       // foggy sectors. Default is to disable relative
+                                       // lighting in foggy sectors.
+      nofakecontrast = <bool>;         // Disables use of fake contrast on this sidedef.
+      smoothlighting = <bool>;         // Use smooth fake contrast.
+      clipmidtex = <bool>;             // Side's mid textures are clipped to floor and ceiling.
+      wrapmidtex = <bool>;             // Side's mid textures are wrapped.
+      nodecals = <bool>;               // Disables decals on the sidedef.
 	  
 	  nogradient_top = <bool>;	    // disables color gradient on upper tier. (Hardware rendering only.)
 	  flipgradient_top = <bool>;    // flips gradient colors on upper tier. (Hardware rendering only.)
@@ -510,6 +519,9 @@ Coloriation options added
 1.32 28.06.2021
 Blocklandmonsters MBF21 flag
 
+1.33 06.11.2021
+Added separate light levels for sidedef tiers (top/mid/bottom)
+
 ===============================================================================
 EOF
 ===============================================================================

src/gamedata/r_defs.h

@@ -1151,15 +1151,20 @@ class DBaseDecal;
 
 enum
 {
-	WALLF_ABSLIGHTING	 = 1,	// Light is absolute instead of relative
+	WALLF_ABSLIGHTING			= 1,	// Light is absolute instead of relative
-	WALLF_NOAUTODECALS	 = 2,	// Do not attach impact decals to this wall
+	WALLF_NOAUTODECALS			= 2,	// Do not attach impact decals to this wall
-	WALLF_NOFAKECONTRAST = 4,	// Don't do fake contrast for this wall in side_t::GetLightLevel
+	WALLF_NOFAKECONTRAST		= 4,	// Don't do fake contrast for this wall in side_t::GetLightLevel
-	WALLF_SMOOTHLIGHTING = 8,   // Similar to autocontrast but applies to all angles.
+	WALLF_SMOOTHLIGHTING		= 8,	// Similar to autocontrast but applies to all angles.
-	WALLF_CLIP_MIDTEX	 = 16,	// Like the line counterpart, but only for this side.
+	WALLF_CLIP_MIDTEX			= 16,	// Like the line counterpart, but only for this side.
-	WALLF_WRAP_MIDTEX	 = 32,	// Like the line counterpart, but only for this side.
+	WALLF_WRAP_MIDTEX			= 32,	// Like the line counterpart, but only for this side.
-	WALLF_POLYOBJ		 = 64,	// This wall belongs to a polyobject.
+	WALLF_POLYOBJ				= 64,	// This wall belongs to a polyobject.
-	WALLF_LIGHT_FOG      = 128,	// This wall's Light is used even in fog.
+	WALLF_LIGHT_FOG				= 128,	// This wall's Light is used even in fog.
-	WALLF_EXTCOLOR		 = 256,	// enables the extended color options (flagged to allow the renderer to easily skip the relevant code)
+	WALLF_EXTCOLOR				= 256,	// enables the extended color options (flagged to allow the renderer to easily skip the relevant code)
+
+	WALLF_ABSLIGHTING_TIER		= 512,	// Per-tier absolute lighting flags
+	WALLF_ABSLIGHTING_TOP		= WALLF_ABSLIGHTING_TIER << 0, 	// Top tier light is absolute instead of relative
+	WALLF_ABSLIGHTING_MID		= WALLF_ABSLIGHTING_TIER << 1, 	// Mid tier light is absolute instead of relative
+	WALLF_ABSLIGHTING_BOTTOM 	= WALLF_ABSLIGHTING_TIER << 2,	// Bottom tier light is absolute instead of relative
 };
 
 struct side_t
@@ -1216,6 +1221,7 @@ struct side_t
 	uint32_t	LeftSide, RightSide;	// [RH] Group walls into loops
 	uint16_t	TexelLength;
 	int16_t		Light;
+	int16_t		TierLights[3];	// per-tier light levels
 	uint16_t	Flags;
 	int			UDMFIndex;		// needed to access custom UDMF fields which are stored in loading order.
 	FLightNode * lighthead;		// all dynamic lights that may affect this wall
@@ -1224,13 +1230,19 @@ struct side_t
 	int numsegs;
 	int sidenum;
 
-	int GetLightLevel (bool foggy, int baselight, bool is3dlight=false, int *pfakecontrast_usedbygzdoom=NULL) const;
+	int GetLightLevel (bool foggy, int baselight, int which, bool is3dlight=false, int *pfakecontrast_usedbygzdoom=NULL) const;
 
 	void SetLight(int16_t l)
 	{
 		Light = l;
 	}
 
+	void SetLight(int16_t l, int which)
+	{
+		TierLights[which] = l;
+	}
+
+
 	FLevelLocals *GetLevel()
 	{
 		return sector->Level;

src/maploader/udmf.cpp

@@ -1323,6 +1323,30 @@ public:
 				Flag(sd->Flags, WALLF_ABSLIGHTING, key);
 				continue;
 
+			case NAME_light_top:
+				sd->SetLight(CheckInt(key), side_t::top);
+				continue;
+				
+			case NAME_lightabsolute_top:
+				Flag(sd->Flags, WALLF_ABSLIGHTING_TOP, key);
+				continue;
+
+			case NAME_light_mid:
+				sd->SetLight(CheckInt(key), side_t::mid);
+				continue;
+
+			case NAME_lightabsolute_mid:
+				Flag(sd->Flags, WALLF_ABSLIGHTING_MID, key);
+				continue;
+
+			case NAME_light_bottom:
+				sd->SetLight(CheckInt(key), side_t::bottom);
+				continue;
+
+			case NAME_lightabsolute_bottom:
+				Flag(sd->Flags, WALLF_ABSLIGHTING_BOTTOM, key);
+				continue;
+
 			case NAME_lightfog:
 				Flag(sd->Flags, WALLF_LIGHT_FOG, key);
 				continue;

src/namedef_custom.h

@@ -746,6 +746,12 @@ xx(scaley_bottom)
 xx(light)
 xx(lightabsolute)
 xx(lightfog)
+xx(light_top)
+xx(lightabsolute_top)
+xx(light_mid)
+xx(lightabsolute_mid)
+xx(light_bottom)
+xx(lightabsolute_bottom)
 xx(nofakecontrast)
 xx(smoothlighting)
 xx(blockprojectiles)

src/playsim/p_sectors.cpp

@@ -1533,11 +1533,18 @@ void line_t::AdjustLine()
 //
 //==========================================================================
 
-int side_t::GetLightLevel (bool foggy, int baselight, bool is3dlight, int *pfakecontrast) const
+int side_t::GetLightLevel (bool foggy, int baselight, int which, bool is3dlight, int *pfakecontrast) const
 {
-	if (!is3dlight && (Flags & WALLF_ABSLIGHTING))
+	if (!is3dlight)
 	{
-		baselight = Light;
+		if (Flags & (WALLF_ABSLIGHTING_TIER << which))
+		{
+			baselight = TierLights[which];
+		}
+		else if (Flags & WALLF_ABSLIGHTING)
+		{
+			baselight = Light + TierLights[which];
+		}
 	}
 
 	if (pfakecontrast != NULL)
@@ -1576,9 +1583,9 @@ int side_t::GetLightLevel (bool foggy, int baselight, bool is3dlight, int *pfake
 			}
 		}
 	}
-	if (!is3dlight && !(Flags & WALLF_ABSLIGHTING) && (!foggy || (Flags & WALLF_LIGHT_FOG)))
+	if (!is3dlight && !(Flags & WALLF_ABSLIGHTING) && !(Flags & (WALLF_ABSLIGHTING_TIER << which)) && (!foggy || (Flags & WALLF_LIGHT_FOG)))
 	{
-		baselight += this->Light;
+		baselight += this->Light + this->TierLights[which];
 	}
 	return baselight;
 }
@@ -1619,4 +1626,3 @@ void vertex_t::RecalcVertexHeights()
 	if (numheights <= 2) numheights = 0;	// is not in need of any special attention
 	dirty = false;
 }
-

src/rendering/hwrenderer/scene/hw_walls.cpp

@@ -1996,7 +1996,23 @@ void HWWall::DoFFloorBlocks(HWDrawInfo *di, seg_t * seg, sector_t * frontsector,
 			InverseFloors(di, seg, frontsector, topleft, topright, bottomleft, bottomright);
 	}
 }
-	
+
+inline int CalcRelLight(int lightlevel, int orglightlevel, int rel)
+{
+	if (orglightlevel >= 253)			// with the software renderer fake contrast won't be visible above this.
+	{
+		return 0;
+	}
+	else if (lightlevel - rel > 256)	// the brighter part of fake contrast will be clamped so also clamp the darker part by the same amount for better looks
+	{
+		return 256 - lightlevel + rel;
+	}
+	else
+	{
+		return rel;
+	}
+}
+
 //==========================================================================
 //
 // 
@@ -2103,19 +2119,6 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 	int rel = 0;
 	int orglightlevel = hw_ClampLight(frontsector->lightlevel);
 	bool foggy = (!Colormap.FadeColor.isBlack() || di->Level->flags&LEVEL_HASFADETABLE);	// fog disables fake contrast
-	lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, false, &rel));
-	if (orglightlevel >= 253)			// with the software renderer fake contrast won't be visible above this.
-	{
-		rellight = 0;
-	}
-	else if (lightlevel - rel > 256)	// the brighter part of fake contrast will be clamped so also clamp the darker part by the same amount for better looks
-	{
-		rellight = 256 - lightlevel + rel;
-	}
-	else
-	{
-		rellight = rel;
-	}
 
 	alpha = 1.0f;
 	RenderStyle = STYLE_Normal;
@@ -2161,6 +2164,8 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 		else
 		{
 			// normal texture
+			lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, side_t::mid, false, &rel));
+			rellight = CalcRelLight(lightlevel, orglightlevel, rel);
 			texture = TexMan.GetGameTexture(seg->sidedef->GetTexture(side_t::mid), true);
 			if (texture && texture->isValid())
 			{
@@ -2229,6 +2234,8 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 
 			if (bch1a < fch1 || bch2a < fch2)
 			{
+				lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, side_t::top, false, &rel));
+				rellight = CalcRelLight(lightlevel, orglightlevel, rel);
 				texture = TexMan.GetGameTexture(seg->sidedef->GetTexture(side_t::top), true);
 				if (texture && texture->isValid())
 				{
@@ -2279,6 +2286,8 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 			texture = tex;
 		}
 		else texture = nullptr;
+		lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, side_t::mid, false, &rel));
+		rellight = CalcRelLight(lightlevel, orglightlevel, rel);
 
 		if (isportal)
 		{
@@ -2297,6 +2306,7 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 		}
 		else
 		{
+
 			if (texture || drawfogboundary)
 			{
 				DoMidTexture(di, seg, drawfogboundary, frontsector, backsector, realfront, realback,
@@ -2305,6 +2315,8 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 
 			if (backsector->e->XFloor.ffloors.Size() || frontsector->e->XFloor.ffloors.Size())
 			{
+				lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, side_t::top, false, &rel));
+				rellight = CalcRelLight(lightlevel, orglightlevel, rel);
 				DoFFloorBlocks(di, seg, frontsector, backsector, fch1, fch2, ffh1, ffh2, bch1, bch2, bfh1, bfh2);
 			}
 		}
@@ -2319,6 +2331,8 @@ void HWWall::Process(HWDrawInfo *di, seg_t *seg, sector_t * frontsector, sector_
 
 		if (bfh1 > ffh1 || bfh2 > ffh2)
 		{
+			lightlevel = hw_ClampLight(seg->sidedef->GetLightLevel(foggy, orglightlevel, side_t::bottom, false, &rel));
+			rellight = CalcRelLight(lightlevel, orglightlevel, rel);
 			texture = TexMan.GetGameTexture(seg->sidedef->GetTexture(side_t::bottom), true);
 			if (texture && texture->isValid())
 			{

src/rendering/swrenderer/line/r_line.cpp

@@ -873,7 +873,7 @@ namespace swrenderer
 		texcoords.ProjectTop(Thread->Viewport.get(), mFrontSector, mBackSector, mLineSegment, WallC, mTopTexture);
 
 		RenderWallPart renderWallpart(Thread);
-		renderWallpart.Render(mFrontSector, mLineSegment, WallC, mTopTexture, x1, x2, walltop.ScreenY, wallupper.ScreenY, texcoords, false, false, OPAQUE);
+		renderWallpart.Render(mFrontSector, mLineSegment, side_t::top, WallC, mTopTexture, x1, x2, walltop.ScreenY, wallupper.ScreenY, texcoords, false, false, OPAQUE);
 	}
 
 	void SWRenderLine::RenderMiddleTexture(int x1, int x2)
@@ -885,7 +885,7 @@ namespace swrenderer
 		texcoords.ProjectMid(Thread->Viewport.get(), mFrontSector, mLineSegment, WallC, mMiddleTexture);
 
 		RenderWallPart renderWallpart(Thread);
-		renderWallpart.Render(mFrontSector, mLineSegment, WallC, mMiddleTexture, x1, x2, walltop.ScreenY, wallbottom.ScreenY, texcoords, false, false, OPAQUE);
+		renderWallpart.Render(mFrontSector, mLineSegment, side_t::mid, WallC, mMiddleTexture, x1, x2, walltop.ScreenY, wallbottom.ScreenY, texcoords, false, false, OPAQUE);
 	}
 
 	void SWRenderLine::RenderBottomTexture(int x1, int x2)
@@ -898,6 +898,6 @@ namespace swrenderer
 		texcoords.ProjectBottom(Thread->Viewport.get(), mFrontSector, mBackSector, mLineSegment, WallC, mBottomTexture);
 
 		RenderWallPart renderWallpart(Thread);
-		renderWallpart.Render(mFrontSector, mLineSegment, WallC, mBottomTexture, x1, x2, walllower.ScreenY, wallbottom.ScreenY, texcoords, false, false, OPAQUE);
+		renderWallpart.Render(mFrontSector, mLineSegment, side_t::bottom, WallC, mBottomTexture, x1, x2, walllower.ScreenY, wallbottom.ScreenY, texcoords, false, false, OPAQUE);
 	}
 }

src/rendering/swrenderer/line/r_renderdrawsegment.cpp

@@ -195,7 +195,7 @@ namespace swrenderer
 		bool additive = (curline->linedef->flags & ML_ADDTRANS) != 0;
 
 		RenderWallPart renderWallpart(Thread);
-		renderWallpart.Render(lightsector, curline, ds->WallC, tex, x1, x2, mceilingclip, mfloorclip, ds->texcoords, true, additive, alpha);
+		renderWallpart.Render(lightsector, curline, side_t::mid, ds->WallC, tex, x1, x2, mceilingclip, mfloorclip, ds->texcoords, true, additive, alpha);
 	}
 
 	void RenderDrawSegment::Render3DFloorWall(DrawSegment *ds, int x1, int x2, F3DFloor *rover, double clipTop, double clipBottom, FSoftwareTexture *rw_pic)
@@ -216,7 +216,7 @@ namespace swrenderer
 		walltexcoords.Project3DFloor(Thread->Viewport.get(), rover, curline, ds->WallC, rw_pic);
 
 		RenderWallPart renderWallpart(Thread);
-		renderWallpart.Render(lightsector, curline, ds->WallC, rw_pic, x1, x2, wallupper.ScreenY, walllower.ScreenY, walltexcoords, true, (rover->flags & FF_ADDITIVETRANS) != 0, Alpha);
+		renderWallpart.Render(lightsector, curline, side_t::top, ds->WallC, rw_pic, x1, x2, wallupper.ScreenY, walllower.ScreenY, walltexcoords, true, (rover->flags & FF_ADDITIVETRANS) != 0, Alpha);
 
 		RenderDecal::RenderDecals(Thread, ds, curline, lightsector, wallupper.ScreenY, walllower.ScreenY, true);
 	}
@@ -580,7 +580,7 @@ namespace swrenderer
 		const sector_t* lightsector = Thread->OpaquePass->FakeFlat(frontsector, &tempsec, nullptr, nullptr, nullptr, 0, 0, 0, 0);
 
 		ProjectedWallLight walllight;
-		walllight.SetColormap(lightsector, curline);
+		walllight.SetColormap(lightsector, curline, side_t::mid);
 		walllight.SetLightLeft(Thread, ds->WallC);
 
 		RenderFogBoundary renderfog;

src/rendering/swrenderer/line/r_walldraw.cpp

@@ -61,7 +61,7 @@ namespace swrenderer
 		Thread = thread;
 	}
 
-	void RenderWallPart::Render(const sector_t* lightsector, seg_t* curline, const FWallCoords& WallC, FSoftwareTexture* pic, int x1, int x2, const short* walltop, const short* wallbottom, const ProjectedWallTexcoords& texcoords, bool mask, bool additive, fixed_t alpha)
+	void RenderWallPart::Render(const sector_t* lightsector, seg_t* curline, int tier, const FWallCoords& WallC, FSoftwareTexture* pic, int x1, int x2, const short* walltop, const short* wallbottom, const ProjectedWallTexcoords& texcoords, bool mask, bool additive, fixed_t alpha)
 	{
 		if (pic == nullptr)
 			return;
@@ -70,6 +70,7 @@ namespace swrenderer
 		this->x2 = x2;
 		this->lightsector = lightsector;
 		this->curline = curline;
+		this->tier = tier;
 		this->WallC = WallC;
 		this->pic = pic;
 		this->mask = mask;
@@ -78,7 +79,7 @@ namespace swrenderer
 
 		light_list = GetLightList();
 
-		mLight.SetColormap(lightsector, curline);
+		mLight.SetColormap(lightsector, curline, tier);
 		mLight.SetLightLeft(Thread, WallC);
 
 		CameraLight* cameraLight = CameraLight::Instance();
@@ -114,7 +115,7 @@ namespace swrenderer
 				down = (down == most1.ScreenY) ? most2.ScreenY : most1.ScreenY;
 			}
 
-			mLight.SetColormap(lightsector, curline, &lightsector->e->XFloor.lightlist[i]);
+			mLight.SetColormap(lightsector, curline, tier, &lightsector->e->XFloor.lightlist[i]);
 		}
 
 		ProcessNormalWall(up, dwal, texcoords);

src/rendering/swrenderer/line/r_walldraw.h

@@ -47,6 +47,7 @@ namespace swrenderer
 		void Render(
 			const sector_t *lightsector,
 			seg_t *curline,
+			int tier,
 			const FWallCoords &WallC,
 			FSoftwareTexture *pic,
 			int x1,
@@ -70,6 +71,7 @@ namespace swrenderer
 		FSoftwareTexture *pic = nullptr;
 		const sector_t *lightsector = nullptr;
 		seg_t *curline = nullptr;
+		int tier;
 		FWallCoords WallC;
 
 		ProjectedWallLight mLight;

src/rendering/swrenderer/line/r_wallsetup.cpp

@@ -687,7 +687,7 @@ namespace swrenderer
 		}
 	}
 
-	void ProjectedWallLight::SetColormap(const sector_t *frontsector, seg_t *lineseg, lightlist_t *lit)
+	void ProjectedWallLight::SetColormap(const sector_t *frontsector, seg_t *lineseg, int tier, lightlist_t *lit)
 	{
 		if (!lit)
 		{
@@ -695,7 +695,7 @@ namespace swrenderer
 			foggy = frontsector->Level->fadeto || frontsector->Colormap.FadeColor || (frontsector->Level->flags & LEVEL_HASFADETABLE);
 
 			if (!(lineseg->sidedef->Flags & WALLF_POLYOBJ))
-				lightlevel = lineseg->sidedef->GetLightLevel(foggy, frontsector->lightlevel);
+				lightlevel = lineseg->sidedef->GetLightLevel(foggy, frontsector->lightlevel, tier);
 			else
 				lightlevel = frontsector->GetLightLevel();
 		}
@@ -703,7 +703,7 @@ namespace swrenderer
 		{
 			basecolormap = GetColorTable(lit->extra_colormap, frontsector->SpecialColors[sector_t::walltop]);
 			foggy = frontsector->Level->fadeto || basecolormap->Fade || (frontsector->Level->flags & LEVEL_HASFADETABLE);
-			lightlevel = lineseg->sidedef->GetLightLevel(foggy, *lit->p_lightlevel, lit->lightsource != nullptr);
+			lightlevel = lineseg->sidedef->GetLightLevel(foggy, *lit->p_lightlevel, tier, lit->lightsource != nullptr);
 		}
 	}
 }

src/rendering/swrenderer/line/r_wallsetup.h

@@ -119,7 +119,7 @@ namespace swrenderer
 		float GetLightStep() const { return lightstep; }
 		bool IsSpriteLight() const { return spritelight; }
 
-		void SetColormap(const sector_t *frontsector, seg_t *lineseg, lightlist_t *lit = nullptr);
+		void SetColormap(const sector_t *frontsector, seg_t *lineseg, int tier, lightlist_t *lit = nullptr);
 		void SetLightLeft(RenderThread *thread, const FWallCoords &wallc);
 		void SetSpriteLight() { lightleft = 0.0f; lightstep = 0.0f; spritelight = true; }
 

src/rendering/swrenderer/things/r_decal.cpp

@@ -157,6 +157,8 @@ namespace swrenderer
 		if (x1 >= clipper->x2 || x2 <= clipper->x1)
 			return;
 
+		int tier = side_t::mid;
+
 		if (drawsegPass)
 		{
 			uint32_t clipMode = decal->RenderFlags & RF_CLIPMASK;
@@ -203,6 +205,7 @@ namespace swrenderer
 				break;
 
 			case RF_CLIPUPPER:
+				tier = side_t::top;
 				mceilingclip = walltop;
 				mfloorclip = thread->OpaquePass->ceilingclip;
 				break;
@@ -211,6 +214,7 @@ namespace swrenderer
 				return;
 
 			case RF_CLIPLOWER:
+				tier = side_t::bottom;
 				mceilingclip = thread->OpaquePass->floorclip;
 				mfloorclip = wallbottom;
 				break;
@@ -219,7 +223,7 @@ namespace swrenderer
 
 		// Prepare lighting
 		ProjectedWallLight light;
-		light.SetColormap(lightsector, curline);
+		light.SetColormap(lightsector, curline, tier);
 		light.SetLightLeft(thread, WallC);
 		usecolormap = light.GetBaseColormap();