diff --git a/src/swrenderer/scene/r_segs.cpp b/src/swrenderer/scene/r_segs.cpp
index 0ebfaa084..30f4e9033 100644
--- a/src/swrenderer/scene/r_segs.cpp
+++ b/src/swrenderer/scene/r_segs.cpp
@@ -1811,7 +1811,7 @@ bool R_StoreWallRange (int start, int stop)
 	// [ZZ] Only if not an active mirror
 	if (!rw_markportal)
 	{
-		R_RenderDecals(curline->sidedef, draw_segment);
+		R_RenderDecals(curline->sidedef, draw_segment, wallshade);
 	}
 
 	if (rw_markportal)
diff --git a/src/swrenderer/things/r_decal.cpp b/src/swrenderer/things/r_decal.cpp
index a49e90cfb..857e3bc36 100644
--- a/src/swrenderer/things/r_decal.cpp
+++ b/src/swrenderer/things/r_decal.cpp
@@ -33,11 +33,11 @@
 
 namespace swrenderer
 {
-	void R_RenderDecals(side_t *sidedef, drawseg_t *draw_segment)
+	void R_RenderDecals(side_t *sidedef, drawseg_t *draw_segment, int wallshade)
 	{
 		for (DBaseDecal *decal = sidedef->AttachedDecals; decal != NULL; decal = decal->WallNext)
 		{
-			R_RenderDecal(sidedef, decal, draw_segment, 0);
+			R_RenderDecal(sidedef, decal, draw_segment, wallshade, 0);
 		}
 	}
 
@@ -45,7 +45,7 @@ namespace swrenderer
 	//		= 1: drawing masked textures (including sprites)
 	// Currently, only pass = 0 is done or used
 
-	void R_RenderDecal(side_t *wall, DBaseDecal *decal, drawseg_t *clipper, int pass)
+	void R_RenderDecal(side_t *wall, DBaseDecal *decal, drawseg_t *clipper, int wallshade, int pass)
 	{
 		DVector2 decal_left, decal_right, decal_pos;
 		int x1, x2;
diff --git a/src/swrenderer/things/r_decal.h b/src/swrenderer/things/r_decal.h
index 8eeadb77e..a006e2fee 100644
--- a/src/swrenderer/things/r_decal.h
+++ b/src/swrenderer/things/r_decal.h
@@ -8,6 +8,6 @@ namespace swrenderer
 {
 	struct drawseg_t;
 
-	void R_RenderDecals(side_t *wall, drawseg_t *draw_segment);
-	void R_RenderDecal(side_t *wall, DBaseDecal *first, drawseg_t *clipper, int pass);
+	void R_RenderDecals(side_t *wall, drawseg_t *draw_segment, int wallshade);
+	void R_RenderDecal(side_t *wall, DBaseDecal *first, drawseg_t *clipper, int wallshade, int pass);
 }