diff --git a/src/level/doomdata.h b/src/level/doomdata.h
index 5f358e0..e8d9273 100644
--- a/src/level/doomdata.h
+++ b/src/level/doomdata.h
@@ -220,6 +220,20 @@ struct IntVertex
 	TArray<UDMFKey> props;
 };
 
+class kexBBox;
+class kexVec3;
+class kexVec2;
+class kexLightSurface;
+struct vertex_t;
+struct surface_t;
+struct thingLight_t;
+
+struct leaf_t
+{
+	vertex_t *vertex;
+	MapSegGLEx *seg;
+};
+
 struct FLevel
 {
 	FLevel ();
@@ -260,6 +274,42 @@ struct FLevel
 	int NumLines() const { return Lines.Size(); }
 	int NumSectors() const { return Sectors.Size(); }
 	int NumThings() const { return Things.Size(); }
+
+	// Dlight helpers
+
+	leaf_t *leafs;
+	uint8_t *mapPVS;
+
+	bool *bSkySectors;
+	bool *bSSectsVisibleToSky;
+
+	int numLeafs;
+
+	int *segLeafLookup;
+	int *ssLeafLookup;
+	int *ssLeafCount;
+	kexBBox *ssLeafBounds;
+
+	kexBBox *nodeBounds;
+
+	surface_t **segSurfaces[3];
+	surface_t **leafSurfaces[2];
+
+	TArray<thingLight_t*> thingLights;
+	TArray<kexLightSurface*> lightSurfaces;
+
+	const kexVec3 &GetSunColor() const;
+	const kexVec3 &GetSunDirection() const;
+
+	IntSideDef *GetSideDef(const MapSegGLEx *seg);
+	IntSector *GetFrontSector(const MapSegGLEx *seg);
+	IntSector *GetBackSector(const MapSegGLEx *seg);
+	IntSector *GetSectorFromSubSector(const MapSubsectorEx *sub);
+	MapSubsectorEx *PointInSubSector(const int x, const int y);
+	bool PointInsideSubSector(const float x, const float y, const MapSubsectorEx *sub);
+	bool LineIntersectSubSector(const kexVec3 &start, const kexVec3 &end, const MapSubsectorEx *sub, kexVec2 &out);
+	vertex_t *GetSegVertex(int index);
+	bool CheckPVS(MapSubsectorEx *s1, MapSubsectorEx *s2);
 };
 
 const int BLOCKSIZE = 128;
diff --git a/src/lightmap/lightmap.cpp b/src/lightmap/lightmap.cpp
index fac35e3..55f5158 100644
--- a/src/lightmap/lightmap.cpp
+++ b/src/lightmap/lightmap.cpp
@@ -37,6 +37,7 @@
 #include "lightmap.h"
 #include "worker.h"
 #include "kexlib/binFile.h"
+#include "wad.h"
 
 //#define EXPORT_TEXELS_OBJ
 
@@ -269,7 +270,7 @@ kexVec3 kexLightmapBuilder::LightTexelSample(kexTrace &trace, const kexVec3 &ori
     color.Clear();
 
     // check all thing lights
-    for(unsigned int i = 0; i < map->thingLights.Length(); i++)
+    for(unsigned int i = 0; i < map->thingLights.Size(); i++)
     {
         thingLight_t *tl = map->thingLights[i];
 
@@ -282,8 +283,8 @@ kexVec3 kexLightmapBuilder::LightTexelSample(kexTrace &trace, const kexVec3 &ori
         lightOrigin.Set(tl->origin.x,
                         tl->origin.y,
                         !tl->bCeiling ?
-                        tl->sector->floorheight + tl->height :
-                        tl->sector->ceilingheight - tl->height);
+                        tl->sector->data.floorheight + tl->height :
+                        tl->sector->data.ceilingheight - tl->height);
 
         if(plane.Distance(lightOrigin) - plane.d < 0)
         {
@@ -330,7 +331,7 @@ kexVec3 kexLightmapBuilder::LightTexelSample(kexTrace &trace, const kexVec3 &ori
         tracedTexels++;
     }
 
-    if(surface->type != ST_CEILING && map->bSSectsVisibleToSky[surface->subSector - map->mapSSects])
+    if(surface->type != ST_CEILING && map->bSSectsVisibleToSky[surface->subSector - map->GLSubsectors])
     {
         // see if it's exposed to sunlight
         if(EmitFromCeiling(trace, surface, origin, plane.Normal(), &dist))
@@ -346,7 +347,7 @@ kexVec3 kexLightmapBuilder::LightTexelSample(kexTrace &trace, const kexVec3 &ori
     }
 
     // trace against surface lights
-    for(unsigned int i = 0; i < map->lightSurfaces.Length(); ++i)
+    for(unsigned int i = 0; i < map->lightSurfaces.Size(); ++i)
     {
         kexLightSurface *surfaceLight = map->lightSurfaces[i];
 
@@ -650,8 +651,7 @@ void kexLightmapBuilder::LightSurface(const int surfid)
 // and against all nearby thing lights
 //
 
-kexVec3 kexLightmapBuilder::LightCellSample(const int gridid, kexTrace &trace,
-        const kexVec3 &origin, const mapSubSector_t *sub)
+kexVec3 kexLightmapBuilder::LightCellSample(const int gridid, kexTrace &trace, const kexVec3 &origin, const mapSubSector_t *sub)
 {
     kexVec3 color;
     kexVec3 dir;
@@ -666,14 +666,14 @@ kexVec3 kexLightmapBuilder::LightCellSample(const int gridid, kexTrace &trace,
     kexVec3 org;
 
     mapSector = map->GetSectorFromSubSector(sub);
-    bInSkySector = map->bSkySectors[mapSector - map->mapSectors];
+    bInSkySector = map->bSkySectors[mapSector - &map->Sectors[0]];
 
     trace.Trace(origin, origin + (map->GetSunDirection() * 32768));
 
     // did we traced a ceiling surface with a sky texture?
     if(trace.fraction != 1 && trace.hitSurface != NULL)
     {
-        if(trace.hitSurface->bSky && origin.z + gridSize[2] > mapSector->floorheight)
+        if(trace.hitSurface->bSky && origin.z + gridSize[2] > mapSector->data.floorheight)
         {
             color = map->GetSunColor();
             // this cell is inside a sector with a sky texture and is also exposed to sunlight.
@@ -698,15 +698,15 @@ kexVec3 kexLightmapBuilder::LightCellSample(const int gridid, kexTrace &trace,
     }
 
     // trace against all thing lights
-    for(unsigned int i = 0; i < map->thingLights.Length(); i++)
+    for(unsigned int i = 0; i < map->thingLights.Size(); i++)
     {
         tl = map->thingLights[i];
 
         lightOrigin.Set(tl->origin.x,
                         tl->origin.y,
                         !tl->bCeiling ?
-                        (float)tl->sector->floorheight + 16 :
-                        (float)tl->sector->ceilingheight - 16);
+                        (float)tl->sector->data.floorheight + 16 :
+                        (float)tl->sector->data.ceilingheight - 16);
 
         radius = tl->radius;
         intensity = tl->intensity * 4;
@@ -748,13 +748,13 @@ kexVec3 kexLightmapBuilder::LightCellSample(const int gridid, kexTrace &trace,
     // if the cell is sticking out from the ground then at least
     // clamp the origin to the ground level so it can at least
     // have a chance to be sampled by the light
-    if(origin.z + gridSize[2] > mapSector->floorheight)
+    if(origin.z + gridSize[2] > mapSector->data.floorheight)
     {
-        org.z = (float)mapSector->floorheight + 2;
+        org.z = (float)mapSector->data.floorheight + 2;
     }
 
     // trace against all light surfaces
-    for(unsigned int i = 0; i < map->lightSurfaces.Length(); ++i)
+    for(unsigned int i = 0; i < map->lightSurfaces.Size(); ++i)
     {
         kexLightSurface *surfaceLight = map->lightSurfaces[i];
 
@@ -824,7 +824,7 @@ void kexLightmapBuilder::LightGrid(const int gridid)
     bInRange = false;
 
     // is this cell even inside the world?
-    for(int i = 0; i < map->numSSects; ++i)
+    for(int i = 0; i < map->NumGLSubsectors; ++i)
     {
         if(bounds.IntersectingBox(map->ssLeafBounds[i]))
         {
@@ -888,7 +888,7 @@ void kexLightmapBuilder::CreateLightGrid()
     kexVec3 mins, maxs;
 
     // get the bounding box of the root BSP node
-    numNodes = map->numNodes-1;
+    numNodes = map->NumGLNodes-1;
     if(numNodes < 0)
     {
         numNodes = 0;
diff --git a/src/lightmap/lightmap.h b/src/lightmap/lightmap.h
index 052782a..3a8590d 100644
--- a/src/lightmap/lightmap.h
+++ b/src/lightmap/lightmap.h
@@ -32,6 +32,7 @@
 #define LIGHTMAP_MAX_SIZE  1024
 
 class kexTrace;
+class kexWadFile;
 
 class kexLightmapBuilder
 {
diff --git a/src/lightmap/lightsurface.cpp b/src/lightmap/lightsurface.cpp
index b5617d3..78723c2 100644
--- a/src/lightmap/lightsurface.cpp
+++ b/src/lightmap/lightsurface.cpp
@@ -288,7 +288,7 @@ void kexLightSurface::Subdivide(const float divide)
 // kexLightSurface::TraceSurface
 //
 
-bool kexLightSurface::TraceSurface(kexDoomMap *doomMap, kexTrace &trace, const surface_t *surf,
+bool kexLightSurface::TraceSurface(FLevel *doomMap, kexTrace &trace, const surface_t *surf,
                                    const kexVec3 &origin, float *dist)
 {
     kexVec3 normal;
diff --git a/src/lightmap/lightsurface.h b/src/lightmap/lightsurface.h
index bf1dd01..8af3459 100644
--- a/src/lightmap/lightsurface.h
+++ b/src/lightmap/lightsurface.h
@@ -43,7 +43,7 @@ struct surfaceLightDef
     kexVec3         rgb;
 };
 
-class kexDoomMap;
+struct FLevel;
 class kexTrace;
 
 class kexLightSurface
@@ -55,7 +55,7 @@ public:
     void                    Init(const surfaceLightDef &lightSurfaceDef, surface_t *surface, const bool bWall, const bool bNoCenterPoint);
     void                    Subdivide(const float divide);
     void                    CreateCenterOrigin();
-    bool                    TraceSurface(kexDoomMap *doomMap, kexTrace &trace, const surface_t *surface, const kexVec3 &origin, float *dist);
+    bool                    TraceSurface(FLevel *doomMap, kexTrace &trace, const surface_t *surface, const kexVec3 &origin, float *dist);
 
     const float             OuterCone() const { return outerCone; }
     const float             InnerCone() const { return innerCone; }
diff --git a/src/lightmap/mapdata.cpp b/src/lightmap/mapdata.cpp
index f6f81e2..6922119 100644
--- a/src/lightmap/mapdata.cpp
+++ b/src/lightmap/mapdata.cpp
@@ -36,6 +36,258 @@
 #include "mapData.h"
 #include "lightSurface.h"
 
+static const kexVec3 defaultSunColor(1, 1, 1);
+static const kexVec3 defaultSunDirection(0.45f, 0.3f, 0.9f);
+
+const kexVec3 &FLevel::GetSunColor() const
+{
+	/*if (mapDef != NULL)
+	{
+		return mapDef->sunColor;
+	}*/
+
+	return defaultSunColor;
+}
+
+const kexVec3 &FLevel::GetSunDirection() const
+{
+	/*if (mapDef != NULL)
+	{
+		return mapDef->sunDir;
+	}*/
+
+	return defaultSunDirection;
+}
+
+IntSideDef *FLevel::GetSideDef(const MapSegGLEx *seg)
+{
+	if (seg->linedef == NO_LINE_INDEX)
+	{
+		// skip minisegs
+		return NULL;
+	}
+
+	IntLineDef *line = &Lines[seg->linedef];
+	return &Sides[line->sidenum[seg->side]];
+}
+
+IntSector *FLevel::GetFrontSector(const MapSegGLEx *seg)
+{
+	IntSideDef *side = GetSideDef(seg);
+
+	if (side == NULL)
+	{
+		return NULL;
+	}
+
+	return &Sectors[side->sector];
+}
+
+IntSector *FLevel::GetBackSector(const MapSegGLEx *seg)
+{
+	if (seg->linedef == NO_LINE_INDEX)
+	{
+		// skip minisegs
+		return NULL;
+	}
+
+	IntLineDef *line = &Lines[seg->linedef];
+
+	if (line->flags & ML_TWOSIDED)
+	{
+		mapSideDef_t *backSide = &Sides[line->sidenum[seg->side ^ 1]];
+		return &Sectors[backSide->sector];
+	}
+
+	return NULL;
+}
+
+IntSector *FLevel::GetSectorFromSubSector(const MapSubsectorEx *sub)
+{
+	mapSector_t *sector = NULL;
+
+	// try to find a sector that the subsector belongs to
+	for (int i = 0; i < (int)sub->numlines; i++)
+	{
+		glSeg_t *seg = &GLSegs[sub->firstline + i];
+		if (seg->side != NO_SIDE_INDEX)
+		{
+			sector = GetFrontSector(seg);
+			break;
+		}
+	}
+
+	return sector;
+}
+
+MapSubsectorEx *FLevel::PointInSubSector(const int x, const int y)
+{
+	MapNodeEx   *node;
+	int         side;
+	int         nodenum;
+	kexVec3     dp1;
+	kexVec3     dp2;
+	float       d;
+
+	// single subsector is a special case
+	if (!NumGLNodes)
+	{
+		return &GLSubsectors[0];
+	}
+
+	nodenum = NumGLNodes - 1;
+
+	while (!(nodenum & NF_SUBSECTOR))
+	{
+		node = &GLNodes[nodenum];
+
+		kexVec3 pt1(F(node->x << 16), F(node->y << 16), 0);
+		kexVec3 pt2(F(node->dx << 16), F(node->dy << 16), 0);
+		kexVec3 pos(F(x << 16), F(y << 16), 0);
+
+		dp1 = pt1 - pos;
+		dp2 = (pt2 + pt1) - pos;
+		d = dp1.Cross(dp2).z;
+
+		side = FLOATSIGNBIT(d);
+
+		nodenum = node->children[side ^ 1];
+	}
+
+	return &GLSubsectors[nodenum & ~NF_SUBSECTOR];
+}
+
+bool FLevel::PointInsideSubSector(const float x, const float y, const MapSubsectorEx *sub)
+{
+	surface_t *surf;
+	int i;
+	kexVec2 p(x, y);
+	kexVec2 dp1, dp2;
+	kexVec2 pt1, pt2;
+
+	surf = leafSurfaces[0][sub - GLSubsectors];
+
+	// check to see if the point is inside the subsector leaf
+	for (i = 0; i < surf->numVerts; i++)
+	{
+		pt1 = surf->verts[i].ToVec2();
+		pt2 = surf->verts[(i + 1) % surf->numVerts].ToVec2();
+
+		dp1 = pt1 - p;
+		dp2 = pt2 - p;
+
+		if (dp1.CrossScalar(dp2) < 0)
+		{
+			continue;
+		}
+
+		// this point is outside the subsector leaf
+		return false;
+	}
+
+	return true;
+}
+
+bool FLevel::LineIntersectSubSector(const kexVec3 &start, const kexVec3 &end, const MapSubsectorEx *sub, kexVec2 &out)
+{
+	surface_t *surf;
+	kexVec2 p1, p2;
+	kexVec2 s1, s2;
+	kexVec2 pt;
+	kexVec2 v;
+	float d, u;
+	float newX;
+	float ab;
+	int i;
+
+	surf = leafSurfaces[0][sub - GLSubsectors];
+	p1 = start.ToVec2();
+	p2 = end.ToVec2();
+
+	for (i = 0; i < surf->numVerts; i++)
+	{
+		s1 = surf->verts[i].ToVec2();
+		s2 = surf->verts[(i + 1) % surf->numVerts].ToVec2();
+
+		if ((p1 == p2) || (s1 == s2))
+		{
+			// zero length
+			continue;
+		}
+
+		if ((p1 == s1) || (p2 == s1) || (p1 == s2) || (p2 == s2))
+		{
+			// shares end point
+			continue;
+		}
+
+		// translate to origin
+		pt = p2 - p1;
+		s1 -= p1;
+		s2 -= p1;
+
+		// normalize
+		u = pt.UnitSq();
+		d = kexMath::InvSqrt(u);
+		v = (pt * d);
+
+		// rotate points s1 and s2 so they're on the positive x axis
+		newX = s1.Dot(v);
+		s1.y = s1.CrossScalar(v);
+		s1.x = newX;
+
+		newX = s2.Dot(v);
+		s2.y = s2.CrossScalar(v);
+		s2.x = newX;
+
+		if ((s1.y < 0 && s2.y < 0) || (s1.y >= 0 && s2.y >= 0))
+		{
+			// s1 and s2 didn't cross
+			continue;
+		}
+
+		ab = s2.x + (s1.x - s2.x) * s2.y / (s2.y - s1.y);
+
+		if (ab < 0 || ab >(u * d))
+		{
+			// s1 and s2 crosses but outside of points p1 and p2
+			continue;
+		}
+
+		// intersected
+		out = p1 + (v * ab);
+		return true;
+	}
+
+	return false;
+}
+
+vertex_t *FLevel::GetSegVertex(int index)
+{
+	if (index & 0x8000)
+	{
+		index = (index & 0x7FFF) + NumGLVertices;
+	}
+
+	//return &GLVertices[index];
+	return nullptr;
+}
+
+bool FLevel::CheckPVS(MapSubsectorEx *s1, MapSubsectorEx *s2)
+{
+	uint8_t *vis;
+	int n1, n2;
+
+	n1 = s1 - GLSubsectors;
+	n2 = s2 - GLSubsectors;
+
+	vis = &mapPVS[(((NumGLSubsectors + 7) / 8) * n1)];
+
+	return ((vis[n2 >> 3] & (1 << (n2 & 7))) != 0);
+}
+
+#if 0
+
 const kexVec3 kexDoomMap::defaultSunColor(1, 1, 1);
 const kexVec3 kexDoomMap::defaultSunDirection(0.45f, 0.3f, 0.9f);
 
@@ -955,3 +1207,5 @@ void kexDoomMap::CleanupThingLights()
         delete thingLights[i];
     }
 }
+
+#endif
diff --git a/src/lightmap/mapdata.h b/src/lightmap/mapdata.h
index 380da4f..8274047 100644
--- a/src/lightmap/mapdata.h
+++ b/src/lightmap/mapdata.h
@@ -27,6 +27,66 @@
 
 #pragma once
 
+#include "framework/zdray.h"
+#include "level/level.h"
+
+typedef FLevel kexDoomMap;
+typedef MapSubsectorEx mapSubSector_t;
+typedef MapSegGLEx glSeg_t;
+typedef IntSideDef mapSideDef_t;
+typedef IntSector mapSector_t;
+
+enum mapFlags_t
+{
+    ML_BLOCKING             = 1,    // Solid, is an obstacle.
+    ML_BLOCKMONSTERS        = 2,    // Blocks monsters only.
+    ML_TWOSIDED             = 4,    // Backside will not be present at all if not two sided.
+    ML_TRANSPARENT1         = 2048, // 25% or 75% transcluency?
+    ML_TRANSPARENT2         = 4096  // 25% or 75% transcluency?
+};
+
+#define NO_SIDE_INDEX           -1
+#define NO_LINE_INDEX           0xFFFF
+#define NF_SUBSECTOR            0x8000
+
+struct lightDef_t
+{
+	int             doomednum;
+	float           height;
+	float           radius;
+	float           intensity;
+	float           falloff;
+	bool            bCeiling;
+	kexVec3         rgb;
+};
+
+struct mapDef_t
+{
+	int             map;
+	int             sunIgnoreTag;
+	kexVec3         sunDir;
+	kexVec3         sunColor;
+};
+
+struct thingLight_t
+{
+	IntThing        *mapThing;
+	kexVec2         origin;
+	kexVec3         rgb;
+	float           intensity;
+	float           falloff;
+	float           height;
+	float           radius;
+	bool            bCeiling;
+	mapSector_t     *sector;
+	mapSubSector_t  *ssect;
+};
+
+#include "surfaces.h"
+#include "lightSurface.h"
+
+#if 0
+
 #include "wad.h"
 #include "surfaces.h"
 #include "lightSurface.h"
@@ -270,3 +330,5 @@ private:
     static const kexVec3        defaultSunColor;
     static const kexVec3        defaultSunDirection;
 };
+
+#endif
diff --git a/src/lightmap/surfaces.cpp b/src/lightmap/surfaces.cpp
index f39e8c0..d8ba74b 100644
--- a/src/lightmap/surfaces.cpp
+++ b/src/lightmap/surfaces.cpp
@@ -31,8 +31,8 @@
 //-----------------------------------------------------------------------------
 
 #include "common.h"
-#include "surfaces.h"
 #include "mapData.h"
+#include "surfaces.h"
 
 //#define EXPORT_OBJ
 
@@ -62,16 +62,16 @@ static void Surface_AllocateFromSeg(kexDoomMap &doomMap, glSeg_t *seg)
     front = doomMap.GetFrontSector(seg);
     back = doomMap.GetBackSector(seg);
 
-    top = front->ceilingheight;
-    bottom = front->floorheight;
+    top = front->data.ceilingheight;
+    bottom = front->data.floorheight;
 
     v1 = doomMap.GetSegVertex(seg->v1);
     v2 = doomMap.GetSegVertex(seg->v2);
 
     if(back)
     {
-        bTop = back->ceilingheight;
-        bBottom = back->floorheight;
+        bTop = back->data.ceilingheight;
+        bBottom = back->data.floorheight;
 
         if(bTop == top && bBottom == bottom)
         {
@@ -97,8 +97,8 @@ static void Surface_AllocateFromSeg(kexDoomMap &doomMap, glSeg_t *seg)
                 surf->plane.SetNormal(surf->verts[0], surf->verts[1], surf->verts[2]);
                 surf->plane.SetDistance(surf->verts[0]);
                 surf->type = ST_LOWERSEG;
-                surf->typeIndex = seg - doomMap.mapSegs;
-                surf->subSector = &doomMap.mapSSects[doomMap.segLeafLookup[seg - doomMap.mapSegs]];
+                surf->typeIndex = seg - doomMap.GLSegs;
+                surf->subSector = &doomMap.GLSubsectors[doomMap.segLeafLookup[seg - doomMap.GLSegs]];
 
                 doomMap.segSurfaces[1][surf->typeIndex] = surf;
                 surf->data = (glSeg_t*)seg;
@@ -113,12 +113,12 @@ static void Surface_AllocateFromSeg(kexDoomMap &doomMap, glSeg_t *seg)
         if(top > bTop)
         {
             bool bSky = false;
-            int frontidx = front-doomMap.mapSectors;
-            int backidx = back-doomMap.mapSectors;
+            int frontidx = front - &doomMap.Sectors[0];
+            int backidx = back - &doomMap.Sectors[0];
 
             if(doomMap.bSkySectors[frontidx] && doomMap.bSkySectors[backidx])
             {
-                if(front->ceilingheight != back->ceilingheight && side->toptexture[0] == '-')
+                if(front->data.ceilingheight != back->data.ceilingheight && side->toptexture[0] == '-')
                 {
                     bSky = true;
                 }
@@ -140,9 +140,9 @@ static void Surface_AllocateFromSeg(kexDoomMap &doomMap, glSeg_t *seg)
                 surf->plane.SetNormal(surf->verts[0], surf->verts[1], surf->verts[2]);
                 surf->plane.SetDistance(surf->verts[0]);
                 surf->type = ST_UPPERSEG;
-                surf->typeIndex = seg - doomMap.mapSegs;
+                surf->typeIndex = seg - doomMap.GLSegs;
                 surf->bSky = bSky;
-                surf->subSector = &doomMap.mapSSects[doomMap.segLeafLookup[seg - doomMap.mapSegs]];
+                surf->subSector = &doomMap.GLSubsectors[doomMap.segLeafLookup[seg - doomMap.GLSegs]];
 
                 doomMap.segSurfaces[2][surf->typeIndex] = surf;
                 surf->data = (glSeg_t*)seg;
@@ -171,8 +171,8 @@ static void Surface_AllocateFromSeg(kexDoomMap &doomMap, glSeg_t *seg)
         surf->plane.SetNormal(surf->verts[0], surf->verts[1], surf->verts[2]);
         surf->plane.SetDistance(surf->verts[0]);
         surf->type = ST_MIDDLESEG;
-        surf->typeIndex = seg - doomMap.mapSegs;
-        surf->subSector = &doomMap.mapSSects[doomMap.segLeafLookup[seg - doomMap.mapSegs]];
+        surf->typeIndex = seg - doomMap.GLSegs;
+        surf->subSector = &doomMap.GLSubsectors[doomMap.segLeafLookup[seg - doomMap.GLSegs]];
 
         doomMap.segSurfaces[0][surf->typeIndex] = surf;
         surf->data = (glSeg_t*)seg;
@@ -198,21 +198,19 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
 
     printf("------------- Building leaf surfaces -------------\n");
 
-    doomMap.leafSurfaces[0] = (surface_t**)Mem_Calloc(sizeof(surface_t*) *
-                              doomMap.numSSects, hb_static);
-    doomMap.leafSurfaces[1] = (surface_t**)Mem_Calloc(sizeof(surface_t*) *
-                              doomMap.numSSects, hb_static);
+    doomMap.leafSurfaces[0] = (surface_t**)Mem_Calloc(sizeof(surface_t*) * doomMap.NumGLSubsectors, hb_static);
+    doomMap.leafSurfaces[1] = (surface_t**)Mem_Calloc(sizeof(surface_t*) * doomMap.NumGLSubsectors, hb_static);
 
-    for(i = 0; i < doomMap.numSSects; i++)
+    for(i = 0; i < doomMap.NumGLSubsectors; i++)
     {
-        printf("subsectors: %i / %i\r", i+1, doomMap.numSSects);
+        printf("subsectors: %i / %i\r", i+1, doomMap.NumGLSubsectors);
 
         if(doomMap.ssLeafCount[i] < 3)
         {
             continue;
         }
 
-        sector = doomMap.GetSectorFromSubSector(&doomMap.mapSSects[i]);
+        sector = doomMap.GetSectorFromSubSector(&doomMap.GLSubsectors[i]);
 
         // I will be NOT surprised if some users tries to do something stupid with
         // sector hacks
@@ -225,7 +223,7 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
         surf = (surface_t*)Mem_Calloc(sizeof(surface_t), hb_static);
         surf->numVerts = doomMap.ssLeafCount[i];
         surf->verts = (kexVec3*)Mem_Calloc(sizeof(kexVec3) * surf->numVerts, hb_static);
-        surf->subSector = &doomMap.mapSSects[i];
+        surf->subSector = &doomMap.GLSubsectors[i];
 
         // floor verts
         for(j = 0; j < surf->numVerts; j++)
@@ -234,7 +232,7 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
 
             surf->verts[j].x = leaf->vertex->x;
             surf->verts[j].y = leaf->vertex->y;
-            surf->verts[j].z = sector->floorheight;
+            surf->verts[j].z = sector->data.floorheight;
         }
 
         surf->plane.SetNormal(kexVec3(0, 0, 1));
@@ -250,9 +248,9 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
         surf = (surface_t*)Mem_Calloc(sizeof(surface_t), hb_static);
         surf->numVerts = doomMap.ssLeafCount[i];
         surf->verts = (kexVec3*)Mem_Calloc(sizeof(kexVec3) * surf->numVerts, hb_static);
-        surf->subSector = &doomMap.mapSSects[i];
+        surf->subSector = &doomMap.GLSubsectors[i];
 
-        if(doomMap.bSkySectors[sector-doomMap.mapSectors])
+        if(doomMap.bSkySectors[sector-&doomMap.Sectors[0]])
         {
             surf->bSky = true;
         }
@@ -264,7 +262,7 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
 
             surf->verts[j].x = leaf->vertex->x;
             surf->verts[j].y = leaf->vertex->y;
-            surf->verts[j].z = sector->ceilingheight;
+            surf->verts[j].z = sector->data.ceilingheight;
         }
 
         surf->plane.SetNormal(kexVec3(0, 0, -1));
@@ -278,7 +276,7 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
         surfaces.Push(surf);
     }
 
-    printf("\nLeaf surfaces: %i\n", surfaces.Length() - doomMap.numSSects);
+    printf("\nLeaf surfaces: %i\n", surfaces.Length() - doomMap.NumGLSubsectors);
 }
 
 //
@@ -287,19 +285,16 @@ static void Surface_AllocateFromLeaf(kexDoomMap &doomMap)
 
 void Surface_AllocateFromMap(kexDoomMap &doomMap)
 {
-    doomMap.segSurfaces[0] = (surface_t**)Mem_Calloc(sizeof(surface_t*) *
-                             doomMap.numSegs, hb_static);
-    doomMap.segSurfaces[1] = (surface_t**)Mem_Calloc(sizeof(surface_t*) *
-                             doomMap.numSegs, hb_static);
-    doomMap.segSurfaces[2] = (surface_t**)Mem_Calloc(sizeof(surface_t*) *
-                             doomMap.numSegs, hb_static);
+    doomMap.segSurfaces[0] = (surface_t**)Mem_Calloc(sizeof(surface_t*) * doomMap.NumGLSegs, hb_static);
+    doomMap.segSurfaces[1] = (surface_t**)Mem_Calloc(sizeof(surface_t*) * doomMap.NumGLSegs, hb_static);
+    doomMap.segSurfaces[2] = (surface_t**)Mem_Calloc(sizeof(surface_t*) * doomMap.NumGLSegs, hb_static);
 
     printf("------------- Building seg surfaces -------------\n");
 
-    for(int i = 0; i < doomMap.numSegs; i++)
+    for(int i = 0; i < doomMap.NumGLSegs; i++)
     {
-        Surface_AllocateFromSeg(doomMap, &doomMap.mapSegs[i]);
-        printf("segs: %i / %i\r", i+1, doomMap.numSegs);
+        Surface_AllocateFromSeg(doomMap, &doomMap.GLSegs[i]);
+        printf("segs: %i / %i\r", i+1, doomMap.NumGLSegs);
     }
 
     printf("\nSeg surfaces: %i\n", surfaces.Length());
diff --git a/src/lightmap/surfaces.h b/src/lightmap/surfaces.h
index 02015b5..2f0754c 100644
--- a/src/lightmap/surfaces.h
+++ b/src/lightmap/surfaces.h
@@ -27,7 +27,7 @@
 
 #pragma once
 
-struct mapSubSector_t;
+struct MapSubsectorEx;
 
 enum surfaceType_t
 {
@@ -61,12 +61,11 @@ struct surface_t
     int                     typeIndex;
     void                    *data;
     bool                    bSky;
-    mapSubSector_t          *subSector;
+	MapSubsectorEx          *subSector;
 };
 
 extern kexArray<surface_t*> surfaces;
 
-class kexDoomMap;
-class kexWadFile;
+struct FLevel;
 
-void Surface_AllocateFromMap(kexDoomMap &doomMap);
+void Surface_AllocateFromMap(FLevel &doomMap);
diff --git a/src/lightmap/trace.cpp b/src/lightmap/trace.cpp
index ce0ebd8..afa99d0 100644
--- a/src/lightmap/trace.cpp
+++ b/src/lightmap/trace.cpp
@@ -80,7 +80,7 @@ void kexTrace::Trace(const kexVec3 &startVec, const kexVec3 &endVec)
         return;
     }
 
-    TraceBSPNode(map->numNodes - 1);
+    TraceBSPNode(map->NumGLNodes - 1);
 }
 
 //
@@ -201,7 +201,7 @@ void kexTrace::TraceSubSector(int num)
     int i;
     int j;
 
-    sub = &map->mapSSects[num];
+    sub = &map->GLSubsectors[num];
 
     if(!map->ssLeafBounds[num].LineIntersect(start, end))
     {
@@ -209,18 +209,17 @@ void kexTrace::TraceSubSector(int num)
     }
 
     // test line segments
-    for(i = 0; i < sub->numsegs; i++)
+    for(i = 0; i < (int)sub->numlines; i++)
     {
-        int segnum = sub->firstseg + i;
+        int segnum = sub->firstline + i;
 
         for(j = 0; j < 3; j++)
         {
             if(j == 0)
             {
-                int linenum = map->mapSegs[segnum].linedef;
+                int linenum = map->GLSegs[segnum].linedef;
 
-                if(linenum != NO_LINE_INDEX && map->mapLines[linenum].flags &
-                        (ML_TWOSIDED|ML_TRANSPARENT1|ML_TRANSPARENT2))
+                if(linenum != NO_LINE_INDEX && map->Lines[linenum].flags & (ML_TWOSIDED|ML_TRANSPARENT1|ML_TRANSPARENT2))
                 {
                     // don't trace transparent 2-sided lines
                     continue;
@@ -243,7 +242,7 @@ void kexTrace::TraceSubSector(int num)
 
 void kexTrace::TraceBSPNode(int num)
 {
-    mapNode_t *node;
+    MapNodeEx *node;
     kexVec3 dp1;
     kexVec3 dp2;
     float d;
@@ -260,7 +259,7 @@ void kexTrace::TraceBSPNode(int num)
         return;
     }
 
-    node = &map->nodes[num];
+    node = &map->GLNodes[num];
 
     kexVec3 pt1(F(node->x << 16), F(node->y << 16), 0);
     kexVec3 pt2(F(node->dx << 16), F(node->dy << 16), 0);
diff --git a/src/lightmap/trace.h b/src/lightmap/trace.h
index d5495df..4d32627 100644
--- a/src/lightmap/trace.h
+++ b/src/lightmap/trace.h
@@ -27,7 +27,7 @@
 
 #pragma once
 
-class kexDoomMap;
+struct FLevel;
 
 class kexTrace
 {
@@ -35,7 +35,7 @@ public:
     kexTrace();
     ~kexTrace();
 
-    void                Init(kexDoomMap &doomMap);
+    void                Init(FLevel &doomMap);
     void                Trace(const kexVec3 &startVec, const kexVec3 &endVec);
 
     kexVec3             start;
@@ -51,6 +51,6 @@ private:
     void                TraceSubSector(int num);
     void                TraceSurface(surface_t *surface);
 
-    kexDoomMap          *map;
+	FLevel          *map;
 
 };