diff --git a/src/common/rendering/hwrenderer/data/hw_renderstate.h b/src/common/rendering/hwrenderer/data/hw_renderstate.h
index 4ada8a452..236cc9e45 100644
--- a/src/common/rendering/hwrenderer/data/hw_renderstate.h
+++ b/src/common/rendering/hwrenderer/data/hw_renderstate.h
@@ -491,11 +491,6 @@ public:
 		mSurfaceUniforms.uAddColor = toFVector4(pe);
 	}
 
-	void SetAddColor(FVector4 color)
-	{
-		mSurfaceUniforms.uAddColor = color;
-	}
-
 	void SetNpotEmulation(float factor, float offset)
 	{
 #ifdef NPOT_EMULATION
diff --git a/src/rendering/hwrenderer/scene/hw_portal.cpp b/src/rendering/hwrenderer/scene/hw_portal.cpp
index a2f444ccf..698fa432e 100644
--- a/src/rendering/hwrenderer/scene/hw_portal.cpp
+++ b/src/rendering/hwrenderer/scene/hw_portal.cpp
@@ -1042,11 +1042,6 @@ void HWHorizonPortal::DrawContents(HWDrawInfo *di, FRenderState &state)
 	}
 	di->SetCameraPos(vp.Pos);
 
-	if (level.lightmaps && texture->GetID() == skyflatnum)
-	{
-		state.SetAddColor(FVector4(level.SunColor * level.SunIntensity, 0.0f));
-	}
-
 	if (texture->isFullbright())
 	{
 		// glowing textures are always drawn full bright without color
@@ -1060,6 +1055,12 @@ void HWHorizonPortal::DrawContents(HWDrawInfo *di, FRenderState &state)
 		SetFog(state, di->Level, di->lightmode, origin->lightlevel, rel, di->isFullbrightScene(), &origin->colormap, false, di->drawctx->portalState.inskybox);
 	}
 
+	if (origin->sunlight)
+	{
+		float attenuation = std::max(FVector3(sp->plane.normal) | level.SunDirection, 0.0f);
+		FVector3 suncolor = level.SunColor * (attenuation * level.SunIntensity);
+		state.SetDynLight(suncolor.X, suncolor.Y, suncolor.Z);
+	}
 
 	state.EnableBrightmap(true);
 	state.SetMaterial(texture, UF_Texture, 0, CLAMP_NONE, NO_TRANSLATION, -1);
@@ -1067,11 +1068,6 @@ void HWHorizonPortal::DrawContents(HWDrawInfo *di, FRenderState &state)
 	state.AlphaFunc(Alpha_GEqual, 0.f);
 	state.SetRenderStyle(STYLE_Source);
 
-	if (level.lightmaps && texture->GetID() == skyflatnum)
-	{
-		state.SetAddColor(FVector4(0.0f, 0.0f, 0.0f, 0.0f));
-	}
-
 	bool texmatrix = SetPlaneTextureRotation(state, sp, texture);
 
 	for (unsigned i = 0; i < vcount; i += 4)
@@ -1082,6 +1078,9 @@ void HWHorizonPortal::DrawContents(HWDrawInfo *di, FRenderState &state)
 
 	if (texmatrix)
 		state.SetTextureMatrix(VSMatrix::identity());
+
+	if (origin->sunlight)
+		state.SetDynLight(0.0f, 0.0f, 0.0f);
 }
 
 
diff --git a/src/rendering/hwrenderer/scene/hw_portal.h b/src/rendering/hwrenderer/scene/hw_portal.h
index d1c1c353d..a3e88f64a 100644
--- a/src/rendering/hwrenderer/scene/hw_portal.h
+++ b/src/rendering/hwrenderer/scene/hw_portal.h
@@ -39,6 +39,7 @@ struct HWHorizonInfo
 	int lightlevel;
 	FColormap colormap;
 	PalEntry specialcolor;
+	bool sunlight;
 };
 
 struct FPortalSceneState;
diff --git a/src/rendering/hwrenderer/scene/hw_walls.cpp b/src/rendering/hwrenderer/scene/hw_walls.cpp
index 4b1c6b296..dc08b1b83 100644
--- a/src/rendering/hwrenderer/scene/hw_walls.cpp
+++ b/src/rendering/hwrenderer/scene/hw_walls.cpp
@@ -842,6 +842,7 @@ bool HWWall::DoHorizon(HWWallDispatcher *di, FRenderState& state, seg_t * seg,se
 				hi.lightlevel = hw_ClampLight(fs->GetCeilingLight());
 				hi.colormap = fs->Colormap;
 				hi.specialcolor = fs->SpecialColors[sector_t::ceiling];
+				hi.sunlight = level.lightmaps && fs->GetTexture(sector_t::floor) == skyflatnum && level.SunDirection.Z < 0.0f;
 
 				if (fs->e->XFloor.ffloors.Size())
 				{
@@ -871,6 +872,7 @@ bool HWWall::DoHorizon(HWWallDispatcher *di, FRenderState& state, seg_t * seg,se
 				hi.lightlevel = hw_ClampLight(fs->GetFloorLight());
 				hi.colormap = fs->Colormap;
 				hi.specialcolor = fs->SpecialColors[sector_t::floor];
+				hi.sunlight = level.lightmaps && fs->GetTexture(sector_t::ceiling) == skyflatnum && level.SunDirection.Z > 0.0f;
 
 				if (fs->e->XFloor.ffloors.Size())
 				{