diff --git a/src/common/rendering/hwrenderer/data/hw_skydome.cpp b/src/common/rendering/hwrenderer/data/hw_skydome.cpp
index aa726d02b..837f4023e 100644
--- a/src/common/rendering/hwrenderer/data/hw_skydome.cpp
+++ b/src/common/rendering/hwrenderer/data/hw_skydome.cpp
@@ -127,9 +127,10 @@ FSkyVertexBuffer::FSkyVertexBuffer()
 	static const FVertexBufferAttribute format[] = {
 		{ 0, VATTR_VERTEX, VFmt_Float3, (int)myoffsetof(FSkyVertex, x) },
 		{ 0, VATTR_TEXCOORD, VFmt_Float2, (int)myoffsetof(FSkyVertex, u) },
-		{ 0, VATTR_COLOR, VFmt_Byte4, (int)myoffsetof(FSkyVertex, color) }
+		{ 0, VATTR_COLOR, VFmt_Byte4, (int)myoffsetof(FSkyVertex, color) },
+		{ 0, VATTR_LIGHTMAP, VFmt_Float3, (int)myoffsetof(FSkyVertex, lu) },
 	};
-	mVertexBuffer->SetFormat(1, 3, sizeof(FSkyVertex), format);
+	mVertexBuffer->SetFormat(1, 4, sizeof(FSkyVertex), format);
 	mVertexBuffer->SetData(mVertices.Size() * sizeof(FSkyVertex), &mVertices[0], BufferUsageType::Static);
 }
 
diff --git a/src/common/rendering/hwrenderer/data/hw_skydome.h b/src/common/rendering/hwrenderer/data/hw_skydome.h
index 0016b3138..f794e96bb 100644
--- a/src/common/rendering/hwrenderer/data/hw_skydome.h
+++ b/src/common/rendering/hwrenderer/data/hw_skydome.h
@@ -16,7 +16,7 @@ const int skyoffsetfactor = 57;
 
 struct FSkyVertex
 {
-	float x, y, z, u, v;
+	float x, y, z, u, v, lu, lv, lindex;
 	PalEntry color;
 
 	void Set(float xx, float zz, float yy, float uu=0, float vv=0, PalEntry col=0xffffffff)
@@ -26,6 +26,9 @@ struct FSkyVertex
 		y = yy;
 		u = uu;
 		v = vv;
+		lu = 0.0f;
+		lv = 0.0f;
+		lindex = -1.0f;
 		color = col;
 	}
 
@@ -36,6 +39,9 @@ struct FSkyVertex
 		z = zz;
 		u = uu;
 		v = vv;
+		lu = 0.0f;
+		lv = 0.0f;
+		lindex = -1.0f;
 		color = col;
 	}