diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index e7606aa5c..4a0e5df98 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -958,7 +958,6 @@ set (PCH_SOURCES
 	rendering/hwrenderer/hw_entrypoint.cpp
 	rendering/hwrenderer/data/hw_vertexbuilder.cpp
 	rendering/hwrenderer/data/flatvertices.cpp
-	rendering/hwrenderer/data/hw_viewpointbuffer.cpp
 	rendering/hwrenderer/dynlights/hw_aabbtree.cpp
 	rendering/hwrenderer/dynlights/hw_shadowmap.cpp
 	rendering/hwrenderer/dynlights/hw_lightbuffer.cpp
@@ -1143,11 +1142,11 @@ set (PCH_SOURCES
 	common/objects/dobjgc.cpp
 	common/objects/dobjtype.cpp
 	common/rendering/r_videoscale.cpp
+	common/rendering/hwrenderer/data/hw_viewpointbuffer.cpp
 	common/rendering/hwrenderer/data/hw_cvars.cpp
 	common/rendering/hwrenderer/data/hw_vrmodes.cpp
 	common/rendering/hwrenderer/postprocessing/hw_postprocess.cpp
 	common/rendering/hwrenderer/postprocessing/hw_postprocess_cvars.cpp
-
 	common/rendering/gl_load/gl_interface.cpp
 	common/scripting/core/dictionary.cpp
 	common/scripting/core/dynarrays.cpp
diff --git a/src/rendering/hwrenderer/data/hw_viewpointbuffer.cpp b/src/common/rendering/hwrenderer/data/hw_viewpointbuffer.cpp
similarity index 100%
rename from src/rendering/hwrenderer/data/hw_viewpointbuffer.cpp
rename to src/common/rendering/hwrenderer/data/hw_viewpointbuffer.cpp
diff --git a/src/rendering/hwrenderer/data/hw_viewpointbuffer.h b/src/common/rendering/hwrenderer/data/hw_viewpointbuffer.h
similarity index 100%
rename from src/rendering/hwrenderer/data/hw_viewpointbuffer.h
rename to src/common/rendering/hwrenderer/data/hw_viewpointbuffer.h
diff --git a/src/maploader/maploader.cpp b/src/maploader/maploader.cpp
index 4a3b66bd6..2fc70e559 100644
--- a/src/maploader/maploader.cpp
+++ b/src/maploader/maploader.cpp
@@ -81,6 +81,7 @@
 #include "xlat/xlat.h"
 #include "vm.h"
 #include "texturemanager.h"
+#include "hwrenderer/data/hw_vertexbuilder.h"
 
 enum
 {
@@ -3223,7 +3224,7 @@ void MapLoader::LoadLevel(MapData *map, const char *lumpname, int position)
 
 	InitRenderInfo();				// create hardware independent renderer resources for the level. This must be done BEFORE the PolyObj Spawn!!!
 	Level->ClearDynamic3DFloorData();	// CreateVBO must be run on the plain 3D floor data.
-	screen->mVertexData->CreateVBO(Level->sectors);
+	CreateVBO(screen->mVertexData, Level->sectors);
 
 	for (auto &sec : Level->sectors)
 	{
diff --git a/src/rendering/hwrenderer/data/flatvertices.cpp b/src/rendering/hwrenderer/data/flatvertices.cpp
index 8b0058ba3..bdee1e5c1 100644
--- a/src/rendering/hwrenderer/data/flatvertices.cpp
+++ b/src/rendering/hwrenderer/data/flatvertices.cpp
@@ -32,16 +32,12 @@
 **
 */
 
-#include "doomtype.h"
-#include "p_local.h"
-#include "r_state.h"
 #include "c_cvars.h"
-#include "g_levellocals.h"
 #include "flatvertices.h"
 #include "v_video.h"
 #include "cmdlib.h"
+#include "printf.h"
 #include "hwrenderer/data/buffers.h"
-#include "hw_renderstate.h"
 
 //==========================================================================
 //
@@ -94,7 +90,7 @@ FFlatVertexBuffer::FFlatVertexBuffer(int width, int height)
 	};
 	mVertexBuffer->SetFormat(1, 2, sizeof(FFlatVertex), format);
 
-	mIndex = mCurIndex = 0;
+	mIndex = mCurIndex = NUM_RESERVED;
 	mNumReserved = NUM_RESERVED;
 	Copy(0, NUM_RESERVED);
 }
@@ -128,238 +124,6 @@ void FFlatVertexBuffer::OutputResized(int width, int height)
 	Copy(4, 4);
 }
 
-//==========================================================================
-//
-// Initialize a single vertex
-//
-//==========================================================================
-
-void FFlatVertex::SetFlatVertex(vertex_t *vt, const secplane_t & plane)
-{
-	x = (float)vt->fX();
-	y = (float)vt->fY();
-	z = (float)plane.ZatPoint(vt);
-	u = (float)vt->fX()/64.f;
-	v = -(float)vt->fY()/64.f;
-}
-
-//==========================================================================
-//
-// Find a 3D floor
-//
-//==========================================================================
-
-static F3DFloor *Find3DFloor(sector_t *target, sector_t *model)
-{
-	for(unsigned i=0; i<target->e->XFloor.ffloors.Size(); i++)
-	{
-		F3DFloor *ffloor = target->e->XFloor.ffloors[i];
-		if (ffloor->model == model && !(ffloor->flags & FF_THISINSIDE)) return ffloor;
-	}
-	return NULL;
-}
-
-//==========================================================================
-//
-// Creates the vertices for one plane in one subsector
-//
-//==========================================================================
-
-int FFlatVertexBuffer::CreateIndexedSectorVertices(sector_t *sec, const secplane_t &plane, int floor, VertexContainer &verts)
-{
-	unsigned vi = vbo_shadowdata.Reserve(verts.vertices.Size());
-	float diff;
-
-	// Create the actual vertices.
-	if (sec->transdoor && floor) diff = -1.f;
-	else diff = 0.f;
-	for (unsigned i = 0; i < verts.vertices.Size(); i++)
-	{
-		vbo_shadowdata[vi + i].SetFlatVertex(verts.vertices[i].vertex, plane);
-		vbo_shadowdata[vi + i].z += diff;
-	}
-
-	unsigned rt = ibo_data.Reserve(verts.indices.Size());
-	for (unsigned i = 0; i < verts.indices.Size(); i++)
-	{
-		ibo_data[rt + i] = vi + verts.indices[i];
-	}
-	return (int)rt;
-}
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-int FFlatVertexBuffer::CreateIndexedVertices(int h, sector_t *sec, const secplane_t &plane, int floor, VertexContainers &verts)
-{
-	sec->vboindex[h] = vbo_shadowdata.Size();
-	// First calculate the vertices for the sector itself
-	sec->vboheight[h] = sec->GetPlaneTexZ(h);
-    sec->ibocount = verts[sec->Index()].indices.Size();
-	sec->iboindex[h] = CreateIndexedSectorVertices(sec, plane, floor, verts[sec->Index()]);
-
-	// Next are all sectors using this one as heightsec
-	TArray<sector_t *> &fakes = sec->e->FakeFloor.Sectors;
-	for (unsigned g = 0; g < fakes.Size(); g++)
-	{
-		sector_t *fsec = fakes[g];
-		fsec->iboindex[2 + h] = CreateIndexedSectorVertices(fsec, plane, false, verts[fsec->Index()]);
-	}
-
-	// and finally all attached 3D floors
-	TArray<sector_t *> &xf = sec->e->XFloor.attached;
-	for (unsigned g = 0; g < xf.Size(); g++)
-	{
-		sector_t *fsec = xf[g];
-		F3DFloor *ffloor = Find3DFloor(fsec, sec);
-
-		if (ffloor != NULL && ffloor->flags & FF_RENDERPLANES)
-		{
-			bool dotop = (ffloor->top.model == sec) && (ffloor->top.isceiling == h);
-			bool dobottom = (ffloor->bottom.model == sec) && (ffloor->bottom.isceiling == h);
-
-			if (dotop || dobottom)
-			{
-				auto ndx = CreateIndexedSectorVertices(fsec, plane, false, verts[fsec->Index()]);
-				if (dotop) ffloor->top.vindex = ndx;
-				if (dobottom) ffloor->bottom.vindex = ndx;
-			}
-		}
-	}
-	sec->vbocount[h] = vbo_shadowdata.Size() - sec->vboindex[h];
-	return sec->iboindex[h];
-}
-
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-void FFlatVertexBuffer::CreateIndexedFlatVertices(TArray<sector_t> &sectors)
-{
-    auto verts = BuildVertices(sectors);
-
-	int i = 0;
-	/*
-	for (auto &vert : verts)
-	{
-		Printf(PRINT_LOG, "Sector %d\n", i);
-		Printf(PRINT_LOG, "%d vertices, %d indices\n", vert.vertices.Size(), vert.indices.Size());
-		int j = 0;
-		for (auto &v : vert.vertices)
-		{
-			Printf(PRINT_LOG, "    %d: (%2.3f, %2.3f)\n", j++, v.vertex->fX(), v.vertex->fY());
-		}
-		for (unsigned i=0;i<vert.indices.Size();i+=3)
-		{
-			Printf(PRINT_LOG, "     %d, %d, %d\n", vert.indices[i], vert.indices[i + 1], vert.indices[i + 2]);
-		}
-
-		i++;
-	}
-	*/
-
-    
-	for (int h = sector_t::floor; h <= sector_t::ceiling; h++)
-	{
-		for (auto &sec : sectors)
-		{
-			CreateIndexedVertices(h, &sec, sec.GetSecPlane(h), h == sector_t::floor, verts);
-		}
-	}
-
-	// We need to do a final check for Vavoom water and FF_FIX sectors.
-	// No new vertices are needed here. The planes come from the actual sector
-	for (auto &sec : sectors)
-	{
-		for (auto ff : sec.e->XFloor.ffloors)
-		{
-			if (ff->top.model == &sec)
-			{
-				ff->top.vindex = sec.iboindex[ff->top.isceiling];
-			}
-			if (ff->bottom.model == &sec)
-			{
-				ff->bottom.vindex = sec.iboindex[ff->top.isceiling];
-			}
-		}
-	}
-}
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-void FFlatVertexBuffer::UpdatePlaneVertices(sector_t *sec, int plane)
-{
-	int startvt = sec->vboindex[plane];
-	int countvt = sec->vbocount[plane];
-	secplane_t &splane = sec->GetSecPlane(plane);
-	FFlatVertex *vt = &vbo_shadowdata[startvt];
-	FFlatVertex *mapvt = GetBuffer(startvt);
-	for(int i=0; i<countvt; i++, vt++, mapvt++)
-	{
-		vt->z = (float)splane.ZatPoint(vt->x, vt->y);
-		if (plane == sector_t::floor && sec->transdoor) vt->z -= 1;
-		mapvt->z = vt->z;
-	}
-}
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-void FFlatVertexBuffer::CreateVertices(TArray<sector_t> &sectors)
-{
-	vbo_shadowdata.Resize(NUM_RESERVED);
-	CreateIndexedFlatVertices(sectors);
-}
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-void FFlatVertexBuffer::CheckPlanes(sector_t *sector)
-{
-	if (sector->GetPlaneTexZ(sector_t::ceiling) != sector->vboheight[sector_t::ceiling])
-	{
-		UpdatePlaneVertices(sector, sector_t::ceiling);
-		sector->vboheight[sector_t::ceiling] = sector->GetPlaneTexZ(sector_t::ceiling);
-	}
-	if (sector->GetPlaneTexZ(sector_t::floor) != sector->vboheight[sector_t::floor])
-	{
-		UpdatePlaneVertices(sector, sector_t::floor);
-		sector->vboheight[sector_t::floor] = sector->GetPlaneTexZ(sector_t::floor);
-	}
-}
-
-//==========================================================================
-//
-// checks the validity of all planes attached to this sector
-// and updates them if possible.
-//
-//==========================================================================
-
-void FFlatVertexBuffer::CheckUpdate(sector_t *sector)
-{
-	CheckPlanes(sector);
-	sector_t *hs = sector->GetHeightSec();
-	if (hs != NULL) CheckPlanes(hs);
-	for (unsigned i = 0; i < sector->e->XFloor.ffloors.Size(); i++)
-		CheckPlanes(sector->e->XFloor.ffloors[i]->model);
-}
-
 //==========================================================================
 //
 //
@@ -392,17 +156,3 @@ void FFlatVertexBuffer::Copy(int start, int count)
 	Unmap();
 }
 
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
-void FFlatVertexBuffer::CreateVBO(TArray<sector_t> &sectors)
-{
-	vbo_shadowdata.Resize(mNumReserved);
-	FFlatVertexBuffer::CreateVertices(sectors);
-	mCurIndex = mIndex = vbo_shadowdata.Size();
-	Copy(0, mIndex);
-	mIndexBuffer->SetData(ibo_data.Size() * sizeof(uint32_t), &ibo_data[0]);
-}
diff --git a/src/rendering/hwrenderer/data/flatvertices.h b/src/rendering/hwrenderer/data/flatvertices.h
index 6161cea29..04feb8388 100644
--- a/src/rendering/hwrenderer/data/flatvertices.h
+++ b/src/rendering/hwrenderer/data/flatvertices.h
@@ -1,31 +1,9 @@
-// 
-//---------------------------------------------------------------------------
-//
-// Copyright(C) 2005-2016 Christoph Oelckers
-// All rights reserved.
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/
-//
-//--------------------------------------------------------------------------
-//
 
 #ifndef _HW__VERTEXBUFFER_H
 #define _HW__VERTEXBUFFER_H
 
 #include "tarray.h"
 #include "hwrenderer/data/buffers.h"
-#include "hw_vertexbuilder.h"
 #include <atomic>
 #include <mutex>
 
@@ -38,7 +16,6 @@ struct FFlatVertex
 	float x, z, y;	// world position
 	float u, v;		// texture coordinates
 
-	void SetFlatVertex(vertex_t *vt, const secplane_t &plane);
 	void Set(float xx, float zz, float yy, float uu, float vv)
 	{
 		x = xx;
@@ -47,10 +24,25 @@ struct FFlatVertex
 		u = uu;
 		v = vv;
 	}
+
+	void SetVertex(float _x, float _y, float _z = 0)
+	{
+		x = _x;
+		z = _y;
+		y = _z;
+	}
+
+	void SetTexCoord(float _u = 0, float _v = 0)
+	{
+		u = _u;
+		v = _v;
+	}
+
 };
 
 class FFlatVertexBuffer
 {
+public:
 	TArray<FFlatVertex> vbo_shadowdata;
 	TArray<uint32_t> ibo_data;
 
@@ -63,7 +55,7 @@ class FFlatVertexBuffer
 
 
 	static const unsigned int BUFFER_SIZE = 2000000;
-	static const unsigned int BUFFER_SIZE_TO_USE = 1999500;
+	static const unsigned int BUFFER_SIZE_TO_USE = BUFFER_SIZE-500;
 
 public:
 	enum
@@ -86,7 +78,6 @@ public:
 		return std::make_pair(mVertexBuffer, mIndexBuffer);
 	}
 
-	void CreateVBO(TArray<sector_t> &sectors);
 	void Copy(int start, int count);
 
 	FFlatVertex *GetBuffer(int index) const
@@ -117,19 +108,6 @@ public:
 		mVertexBuffer->Unmap();
 	}
 
-private:
-	int CreateIndexedSectionVertices(subsector_t *sub, const secplane_t &plane, int floor, VertexContainer &cont);
-	int CreateIndexedSectorVertices(sector_t *sec, const secplane_t &plane, int floor, VertexContainer &cont);
-	int CreateIndexedVertices(int h, sector_t *sec, const secplane_t &plane, int floor, VertexContainers &cont);
-	void CreateIndexedFlatVertices(TArray<sector_t> &sectors);
-
-	void UpdatePlaneVertices(sector_t *sec, int plane);
-protected:
-	void CreateVertices(TArray<sector_t> &sectors);
-	void CheckPlanes(sector_t *sector);
-public:
-	void CheckUpdate(sector_t *sector);
-
 };
 
 #endif
diff --git a/src/rendering/hwrenderer/data/hw_vertexbuilder.cpp b/src/rendering/hwrenderer/data/hw_vertexbuilder.cpp
index a21b3c78f..459b1e605 100644
--- a/src/rendering/hwrenderer/data/hw_vertexbuilder.cpp
+++ b/src/rendering/hwrenderer/data/hw_vertexbuilder.cpp
@@ -24,6 +24,7 @@
 
 #include "g_levellocals.h"
 #include "hw_vertexbuilder.h"
+#include "flatvertices.h"
 #include "earcut.hpp"
 
 
@@ -146,3 +147,255 @@ TArray<VertexContainer> BuildVertices(TArray<sector_t> &sectors)
 	}
 	return verticesPerSector;
 }
+
+//==========================================================================
+//
+// Creates the vertices for one plane in one subsector
+//
+//==========================================================================
+
+//==========================================================================
+//
+// Find a 3D floor
+//
+//==========================================================================
+
+static F3DFloor* Find3DFloor(sector_t* target, sector_t* model)
+{
+	for (unsigned i = 0; i < target->e->XFloor.ffloors.Size(); i++)
+	{
+		F3DFloor* ffloor = target->e->XFloor.ffloors[i];
+		if (ffloor->model == model && !(ffloor->flags & FF_THISINSIDE)) return ffloor;
+	}
+	return NULL;
+}
+
+//==========================================================================
+//
+// Initialize a single vertex
+//
+//==========================================================================
+
+static void SetFlatVertex(FFlatVertex& ffv, vertex_t* vt, const secplane_t& plane)
+{
+	ffv.x = (float)vt->fX();
+	ffv.y = (float)vt->fY();
+	ffv.z = (float)plane.ZatPoint(vt);
+	ffv.u = (float)vt->fX() / 64.f;
+	ffv.v = -(float)vt->fY() / 64.f;
+}
+
+
+
+static int CreateIndexedSectorVertices(FFlatVertexBuffer* fvb, sector_t* sec, const secplane_t& plane, int floor, VertexContainer& verts)
+{
+	auto& vbo_shadowdata = fvb->vbo_shadowdata;
+	unsigned vi = vbo_shadowdata.Reserve(verts.vertices.Size());
+	float diff;
+
+	// Create the actual vertices.
+	if (sec->transdoor && floor) diff = -1.f;
+	else diff = 0.f;
+	for (unsigned i = 0; i < verts.vertices.Size(); i++)
+	{
+		SetFlatVertex(vbo_shadowdata[vi + i], verts.vertices[i].vertex, plane);
+		vbo_shadowdata[vi + i].z += diff;
+	}
+
+	auto& ibo_data = fvb->ibo_data;
+	unsigned rt = ibo_data.Reserve(verts.indices.Size());
+	for (unsigned i = 0; i < verts.indices.Size(); i++)
+	{
+		ibo_data[rt + i] = vi + verts.indices[i];
+	}
+	return (int)rt;
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+static int CreateIndexedVertices(FFlatVertexBuffer* fvb, int h, sector_t* sec, const secplane_t& plane, int floor, VertexContainers& verts)
+{
+	auto& vbo_shadowdata = fvb->vbo_shadowdata;
+	sec->vboindex[h] = vbo_shadowdata.Size();
+	// First calculate the vertices for the sector itself
+	sec->vboheight[h] = sec->GetPlaneTexZ(h);
+	sec->ibocount = verts[sec->Index()].indices.Size();
+	sec->iboindex[h] = CreateIndexedSectorVertices(fvb, sec, plane, floor, verts[sec->Index()]);
+
+	// Next are all sectors using this one as heightsec
+	TArray<sector_t*>& fakes = sec->e->FakeFloor.Sectors;
+	for (unsigned g = 0; g < fakes.Size(); g++)
+	{
+		sector_t* fsec = fakes[g];
+		fsec->iboindex[2 + h] = CreateIndexedSectorVertices(fvb, fsec, plane, false, verts[fsec->Index()]);
+	}
+
+	// and finally all attached 3D floors
+	TArray<sector_t*>& xf = sec->e->XFloor.attached;
+	for (unsigned g = 0; g < xf.Size(); g++)
+	{
+		sector_t* fsec = xf[g];
+		F3DFloor* ffloor = Find3DFloor(fsec, sec);
+
+		if (ffloor != NULL && ffloor->flags & FF_RENDERPLANES)
+		{
+			bool dotop = (ffloor->top.model == sec) && (ffloor->top.isceiling == h);
+			bool dobottom = (ffloor->bottom.model == sec) && (ffloor->bottom.isceiling == h);
+
+			if (dotop || dobottom)
+			{
+				auto ndx = CreateIndexedSectorVertices(fvb, fsec, plane, false, verts[fsec->Index()]);
+				if (dotop) ffloor->top.vindex = ndx;
+				if (dobottom) ffloor->bottom.vindex = ndx;
+			}
+		}
+	}
+	sec->vbocount[h] = vbo_shadowdata.Size() - sec->vboindex[h];
+	return sec->iboindex[h];
+}
+
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+static void CreateIndexedFlatVertices(FFlatVertexBuffer* fvb, TArray<sector_t>& sectors)
+{
+	auto verts = BuildVertices(sectors);
+
+	int i = 0;
+	/*
+	for (auto &vert : verts)
+	{
+		Printf(PRINT_LOG, "Sector %d\n", i);
+		Printf(PRINT_LOG, "%d vertices, %d indices\n", vert.vertices.Size(), vert.indices.Size());
+		int j = 0;
+		for (auto &v : vert.vertices)
+		{
+			Printf(PRINT_LOG, "    %d: (%2.3f, %2.3f)\n", j++, v.vertex->fX(), v.vertex->fY());
+		}
+		for (unsigned i=0;i<vert.indices.Size();i+=3)
+		{
+			Printf(PRINT_LOG, "     %d, %d, %d\n", vert.indices[i], vert.indices[i + 1], vert.indices[i + 2]);
+		}
+
+		i++;
+	}
+	*/
+
+
+	for (int h = sector_t::floor; h <= sector_t::ceiling; h++)
+	{
+		for (auto& sec : sectors)
+		{
+			CreateIndexedVertices(fvb, h, &sec, sec.GetSecPlane(h), h == sector_t::floor, verts);
+		}
+	}
+
+	// We need to do a final check for Vavoom water and FF_FIX sectors.
+	// No new vertices are needed here. The planes come from the actual sector
+	for (auto& sec : sectors)
+	{
+		for (auto ff : sec.e->XFloor.ffloors)
+		{
+			if (ff->top.model == &sec)
+			{
+				ff->top.vindex = sec.iboindex[ff->top.isceiling];
+			}
+			if (ff->bottom.model == &sec)
+			{
+				ff->bottom.vindex = sec.iboindex[ff->top.isceiling];
+			}
+		}
+	}
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+static void UpdatePlaneVertices(FFlatVertexBuffer *fvb, sector_t* sec, int plane)
+{
+	int startvt = sec->vboindex[plane];
+	int countvt = sec->vbocount[plane];
+	secplane_t& splane = sec->GetSecPlane(plane);
+	FFlatVertex* vt = &fvb->vbo_shadowdata[startvt];
+	FFlatVertex* mapvt = fvb->GetBuffer(startvt);
+	for (int i = 0; i < countvt; i++, vt++, mapvt++)
+	{
+		vt->z = (float)splane.ZatPoint(vt->x, vt->y);
+		if (plane == sector_t::floor && sec->transdoor) vt->z -= 1;
+		mapvt->z = vt->z;
+	}
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+static void CreateVertices(FFlatVertexBuffer* fvb, TArray<sector_t>& sectors)
+{
+	fvb->vbo_shadowdata.Resize(FFlatVertexBuffer::NUM_RESERVED);
+	CreateIndexedFlatVertices(fvb, sectors);
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+static void CheckPlanes(FFlatVertexBuffer* fvb, sector_t* sector)
+{
+	if (sector->GetPlaneTexZ(sector_t::ceiling) != sector->vboheight[sector_t::ceiling])
+	{
+		UpdatePlaneVertices(fvb, sector, sector_t::ceiling);
+		sector->vboheight[sector_t::ceiling] = sector->GetPlaneTexZ(sector_t::ceiling);
+	}
+	if (sector->GetPlaneTexZ(sector_t::floor) != sector->vboheight[sector_t::floor])
+	{
+		UpdatePlaneVertices(fvb, sector, sector_t::floor);
+		sector->vboheight[sector_t::floor] = sector->GetPlaneTexZ(sector_t::floor);
+	}
+}
+
+//==========================================================================
+//
+// checks the validity of all planes attached to this sector
+// and updates them if possible.
+//
+//==========================================================================
+
+void CheckUpdate(FFlatVertexBuffer* fvb, sector_t* sector)
+{
+	CheckPlanes(fvb, sector);
+	sector_t* hs = sector->GetHeightSec();
+	if (hs != NULL) CheckPlanes(fvb, hs);
+	for (unsigned i = 0; i < sector->e->XFloor.ffloors.Size(); i++)
+		CheckPlanes(fvb, sector->e->XFloor.ffloors[i]->model);
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
+void CreateVBO(FFlatVertexBuffer* fvb, TArray<sector_t>& sectors)
+{
+	fvb->vbo_shadowdata.Resize(fvb->mNumReserved);
+	CreateVertices(fvb, sectors);
+	fvb->mCurIndex = fvb->mIndex = fvb->vbo_shadowdata.Size();
+	fvb->Copy(0, fvb->mIndex);
+	fvb->mIndexBuffer->SetData(fvb->ibo_data.Size() * sizeof(uint32_t), &fvb->ibo_data[0]);
+}
diff --git a/src/rendering/hwrenderer/data/hw_vertexbuilder.h b/src/rendering/hwrenderer/data/hw_vertexbuilder.h
index e13e5e7af..4fbe9916f 100644
--- a/src/rendering/hwrenderer/data/hw_vertexbuilder.h
+++ b/src/rendering/hwrenderer/data/hw_vertexbuilder.h
@@ -67,4 +67,7 @@ using VertexContainers = TArray<VertexContainer>;
 
 VertexContainers BuildVertices(TArray<sector_t> &sectors);
 
+class FFlatVertexBuffer;
+void CheckUpdate(FFlatVertexBuffer* fvb, sector_t* sector);
+void CreateVBO(FFlatVertexBuffer* fvb, TArray<sector_t>& sectors);
 
diff --git a/src/rendering/hwrenderer/scene/hw_bsp.cpp b/src/rendering/hwrenderer/scene/hw_bsp.cpp
index d2ce57e4d..f8e7c9687 100644
--- a/src/rendering/hwrenderer/scene/hw_bsp.cpp
+++ b/src/rendering/hwrenderer/scene/hw_bsp.cpp
@@ -41,6 +41,7 @@
 #include "hwrenderer/scene/hw_portal.h"
 #include "hwrenderer/utility/hw_clock.h"
 #include "hwrenderer/data/flatvertices.h"
+#include "hwrenderer/data/hw_vertexbuilder.h"
 
 #ifdef ARCH_IA32
 #include <immintrin.h>
@@ -628,7 +629,7 @@ void HWDrawInfo::DoSubsector(subsector_t * sub)
 
 	if (sector->validcount != validcount)
 	{
-		screen->mVertexData->CheckUpdate(sector);
+		CheckUpdate(screen->mVertexData, sector);
 	}
 
 	// [RH] Add particles