diff --git a/src/gl/scene/gl_vertex.cpp b/src/gl/scene/gl_vertex.cpp
index e0ca18b2b..e9aef4459 100644
--- a/src/gl/scene/gl_vertex.cpp
+++ b/src/gl/scene/gl_vertex.cpp
@@ -21,12 +21,9 @@
 //
 
 
-
-#include "gl/system/gl_system.h"
-
-#include "gl/renderer/gl_renderer.h"
-#include "gl/data/gl_vertexbuffer.h"
-#include "gl/scene/gl_drawinfo.h"
+#include "r_defs.h"
+#include "hwrenderer/data/flatvertices.h"
+#include "gl/scene/gl_wall.h"
 
 EXTERN_CVAR(Bool, gl_seamless)
 
@@ -170,3 +167,26 @@ void GLWall::SplitRightEdge(FFlatVertex *&ptr)
 	}
 }
 
+//==========================================================================
+//
+// Create vertices for one wall
+//
+//==========================================================================
+
+void GLWall::CreateVertices(FFlatVertex *&ptr, bool nosplit)
+{
+	bool split = (gl_seamless && !nosplit && seg->sidedef != nullptr && !(seg->sidedef->Flags & WALLF_POLYOBJ) && !(flags & GLWF_NOSPLIT));
+	ptr->Set(glseg.x1, zbottom[0], glseg.y1, tcs[LOLFT].u, tcs[LOLFT].v);
+	ptr++;
+	if (split && glseg.fracleft == 0) SplitLeftEdge(ptr);
+	ptr->Set(glseg.x1, ztop[0], glseg.y1, tcs[UPLFT].u, tcs[UPLFT].v);
+	ptr++;
+	if (split && !(flags & GLWF_NOSPLITUPPER)) SplitUpperEdge(ptr);
+	ptr->Set(glseg.x2, ztop[1], glseg.y2, tcs[UPRGT].u, tcs[UPRGT].v);
+	ptr++;
+	if (split && glseg.fracright == 1) SplitRightEdge(ptr);
+	ptr->Set(glseg.x2, zbottom[1], glseg.y2, tcs[LORGT].u, tcs[LORGT].v);
+	ptr++;
+	if (split && !(flags & GLWF_NOSPLITLOWER)) SplitLowerEdge(ptr);
+}
+
diff --git a/src/gl/scene/gl_wall.h b/src/gl/scene/gl_wall.h
index 49642e838..9b112963d 100644
--- a/src/gl/scene/gl_wall.h
+++ b/src/gl/scene/gl_wall.h
@@ -10,6 +10,8 @@
 #include "textures/textures.h"
 #include "gl/renderer/gl_colormap.h"
 
+#pragma warning(disable:4244)
+
 struct GLHorizonInfo;
 struct F3DFloor;
 struct model_t;
@@ -24,6 +26,7 @@ struct FSectorPortalGroup;
 struct FFlatVertex;
 struct FLinePortalSpan;
 class GLSceneDrawer;
+struct FDynLightData;
 
 enum
 {
@@ -207,7 +210,7 @@ private:
 	bool SplitWallComplex(HWDrawInfo *di, sector_t * frontsector, bool translucent, float& maplightbottomleft, float& maplightbottomright);
 	void SplitWall(HWDrawInfo *di, sector_t * frontsector, bool translucent);
 
-	void SetupLights();
+	bool SetupLights(FDynLightData &lightdata);
 	void MakeVertices(bool nosplit);
 	void RenderWall(int textured);
 	void RenderTextured(int rflags);
@@ -257,6 +260,7 @@ private:
 	void RenderMirrorSurface();
 	void RenderTranslucentWall();
 
+	void CreateVertices(FFlatVertex *&ptr, bool nosplit);
 	void SplitLeftEdge (FFlatVertex *&ptr);
 	void SplitRightEdge(FFlatVertex *&ptr);
 	void SplitUpperEdge(FFlatVertex *&ptr);
diff --git a/src/gl/scene/gl_walls_draw.cpp b/src/gl/scene/gl_walls_draw.cpp
index d24750d79..347a07d04 100644
--- a/src/gl/scene/gl_walls_draw.cpp
+++ b/src/gl/scene/gl_walls_draw.cpp
@@ -42,17 +42,17 @@
 
 EXTERN_CVAR(Bool, gl_seamless)
 
+FDynLightData lightdata;
+
 //==========================================================================
 //
 // Collect lights for shader
 //
 //==========================================================================
-FDynLightData lightdata;
 
-
-void GLWall::SetupLights()
+bool GLWall::SetupLights(FDynLightData &lightdata)
 {
-	if (RenderStyle == STYLE_Add && !level.lightadditivesurfaces) return;	// no lights on additively blended surfaces.
+	if (RenderStyle == STYLE_Add && !level.lightadditivesurfaces) return false;	// no lights on additively blended surfaces.
 
 	// check for wall types which cannot have dynamic lights on them (portal types never get here so they don't need to be checked.)
 	switch (type)
@@ -60,7 +60,7 @@ void GLWall::SetupLights()
 	case RENDERWALL_FOGBOUNDARY:
 	case RENDERWALL_MIRRORSURFACE:
 	case RENDERWALL_COLOR:
-		return;
+		return false;
 	}
 
 	float vtx[]={glseg.x1,zbottom[0],glseg.y1, glseg.x1,ztop[0],glseg.y1, glseg.x2,ztop[1],glseg.y2, glseg.x2,zbottom[1],glseg.y2};
@@ -141,8 +141,7 @@ void GLWall::SetupLights()
 		}
 		node = node->nextLight;
 	}
-
-	dynlightindex = GLRenderer->mLights->UploadLights(lightdata);
+	return true;
 }
 
 //==========================================================================
@@ -155,22 +154,8 @@ void GLWall::MakeVertices(bool nosplit)
 {
 	if (vertcount == 0)
 	{
-		bool split = (gl_seamless && !nosplit && seg->sidedef != NULL && !(seg->sidedef->Flags & WALLF_POLYOBJ) && !(flags & GLWF_NOSPLIT));
-
 		FFlatVertex *ptr = GLRenderer->mVBO->GetBuffer();
-
-		ptr->Set(glseg.x1, zbottom[0], glseg.y1, tcs[LOLFT].u, tcs[LOLFT].v);
-		ptr++;
-		if (split && glseg.fracleft == 0) SplitLeftEdge(ptr);
-		ptr->Set(glseg.x1, ztop[0], glseg.y1, tcs[UPLFT].u, tcs[UPLFT].v);
-		ptr++;
-		if (split && !(flags & GLWF_NOSPLITUPPER)) SplitUpperEdge(ptr);
-		ptr->Set(glseg.x2, ztop[1], glseg.y2, tcs[UPRGT].u, tcs[UPRGT].v);
-		ptr++;
-		if (split && glseg.fracright == 1) SplitRightEdge(ptr);
-		ptr->Set(glseg.x2, zbottom[1], glseg.y2, tcs[LORGT].u, tcs[LORGT].v);
-		ptr++;
-		if (split && !(flags & GLWF_NOSPLITLOWER)) SplitLowerEdge(ptr);
+		CreateVertices(ptr, nosplit);
 		vertcount = GLRenderer->mVBO->GetCount(ptr, &vertindex);
 	}
 }
@@ -389,7 +374,8 @@ void GLWall::RenderTranslucentWall()
 	{
 		if (mDrawer->FixedColormap == CM_DEFAULT && gl_lights && gl.lightmethod == LM_DIRECT)
 		{
-			SetupLights();
+			if (SetupLights(lightdata))
+				dynlightindex = GLRenderer->mLights->UploadLights(lightdata);
 		}
 		if (!gltexture->tex->GetTranslucency()) gl_RenderState.AlphaFunc(GL_GEQUAL, gl_mask_threshold);
 		else gl_RenderState.AlphaFunc(GL_GEQUAL, 0.f);
@@ -419,11 +405,13 @@ void GLWall::Draw(int pass)
 	switch (pass)
 	{
 	case GLPASS_LIGHTSONLY:
-		SetupLights();
+		if (SetupLights(lightdata))
+			dynlightindex = GLRenderer->mLights->UploadLights(lightdata);
 		break;
 
 	case GLPASS_ALL:
-		SetupLights();
+		if (SetupLights(lightdata))
+			dynlightindex = GLRenderer->mLights->UploadLights(lightdata);
 		// fall through
 	case GLPASS_PLAIN:
 		RenderTextured(RWF_TEXTURED);