diff --git a/src/r_poly_sprite.cpp b/src/r_poly_sprite.cpp
index 6de63bbdcd..e4738ab264 100644
--- a/src/r_poly_sprite.cpp
+++ b/src/r_poly_sprite.cpp
@@ -219,6 +219,7 @@ void RenderPolySprite::Render(const TriMatrix &worldToClip, AActor *thing, subse
 		args.uniforms.destalpha = 256;
 		args.uniforms.srcalpha = (uint32_t)(thing->Alpha * 256);
 		args.SetTexture(tex, false);
+		args.uniforms.color = 0;
 		uniforms.flags |= TriUniforms::simple_shade;
 		PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector, TriBlendMode::Shaded);
 	}
@@ -227,6 +228,7 @@ void RenderPolySprite::Render(const TriMatrix &worldToClip, AActor *thing, subse
 		args.uniforms.destalpha = 256;
 		args.uniforms.srcalpha = (uint32_t)(thing->Alpha * 256);
 		args.SetTexture(tex, false);
+		args.uniforms.color = 0;
 		uniforms.flags |= TriUniforms::simple_shade;
 		PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector, TriBlendMode::Shaded);
 	}
diff --git a/src/r_poly_wall.cpp b/src/r_poly_wall.cpp
index 92c669ebf8..2cdcb30192 100644
--- a/src/r_poly_wall.cpp
+++ b/src/r_poly_wall.cpp
@@ -199,7 +199,12 @@ void RenderPolyWall::Render(const TriMatrix &worldToClip)
 	}
 	else
 	{
-		PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector, TriBlendMode::AlphaBlend);
+		args.uniforms.destalpha = (Line->linedef->flags & ML_ADDTRANS) ? 256 : (uint32_t)(256 - Line->linedef->alpha * 256);
+		args.uniforms.srcalpha = (uint32_t)(Line->linedef->alpha * 256);
+		if (args.uniforms.destalpha == 0 && args.uniforms.srcalpha == 256)
+			PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector, TriBlendMode::AlphaBlend);
+		else
+			PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector, TriBlendMode::Add);
 	}
 
 	RenderPolyDecal::RenderWallDecals(worldToClip, Line, SubsectorDepth);