diff --git a/src/hwrenderer/models/hw_models.cpp b/src/hwrenderer/models/hw_models.cpp
index ce22625d89..d4241c0263 100644
--- a/src/hwrenderer/models/hw_models.cpp
+++ b/src/hwrenderer/models/hw_models.cpp
@@ -144,7 +144,8 @@ FModelVertexBuffer::FModelVertexBuffer(bool needindex, bool singleframe)
 		{ 0, VATTR_VERTEX, VFmt_Float3, (int)myoffsetof(FModelVertex, x) },
 		{ 0, VATTR_TEXCOORD, VFmt_Float2, (int)myoffsetof(FModelVertex, u) },
 		{ 0, VATTR_NORMAL, VFmt_Packed_A2R10G10B10, (int)myoffsetof(FModelVertex, packedNormal) },
-		{ 1, VATTR_VERTEX2, VFmt_Float3, (int)myoffsetof(FModelVertex, x) }
+		{ 1, VATTR_VERTEX2, VFmt_Float3, (int)myoffsetof(FModelVertex, x) },
+		{ 1, VATTR_NORMAL2, VFmt_Packed_A2R10G10B10, (int)myoffsetof(FModelVertex, packedNormal) }
 	};
 	mVertexBuffer->SetFormat(2, 4, sizeof(FModelVertex), format);
 }
diff --git a/wadsrc/static/shaders/glsl/main.vp b/wadsrc/static/shaders/glsl/main.vp
index dccbb77c00..a5875318fe 100644
--- a/wadsrc/static/shaders/glsl/main.vp
+++ b/wadsrc/static/shaders/glsl/main.vp
@@ -5,6 +5,7 @@ layout(location = 2) in vec4 aColor;
 #ifndef SIMPLE	// we do not need these for simple shaders
 layout(location = 3) in vec4 aVertex2;
 layout(location = 4) in vec4 aNormal;
+layout(location = 5) in vec4 aNormal2;
 out vec4 pixelpos;
 out vec3 glowdist;
 out vec3 gradientdist;
@@ -62,7 +63,7 @@ void main()
 			gl_ClipDistance[4] = worldcoord.y - ((uSplitBottomPlane.w + uSplitBottomPlane.x * worldcoord.x + uSplitBottomPlane.y * worldcoord.z) * uSplitBottomPlane.z);
 		}
 
-		vWorldNormal = NormalModelMatrix * vec4(normalize(aNormal.xyz), 1.0);
+		vWorldNormal = NormalModelMatrix * vec4(normalize(mix(aNormal.xyz. aNormal2.xyz, uInterpolationFactor)), 1.0);
 		vEyeNormal = NormalViewMatrix * vWorldNormal;
 	#endif