diff --git a/src_rebuild/Game/C/bcollide.c b/src_rebuild/Game/C/bcollide.c
index 4ff9f242..7fc79e9f 100644
--- a/src_rebuild/Game/C/bcollide.c
+++ b/src_rebuild/Game/C/bcollide.c
@@ -868,7 +868,7 @@ int CarBuildingCollision(CAR_DATA *cp, BUILDING_BOX *building, CELL_OBJECT *cop,
 						damage_object(cop, &velocity);
 
 						// smash object
-						if ((model->shape_flags & SHAPE_FLAG_SMASH_QUIET) == 0)
+						if ((model->shape_flags & SHAPE_FLAG_TRANS) == 0)
 						{
 							sip = smashable;
 							match = sip;
diff --git a/src_rebuild/Game/C/debris.c b/src_rebuild/Game/C/debris.c
index 553c2230..0cb43153 100644
--- a/src_rebuild/Game/C/debris.c
+++ b/src_rebuild/Game/C/debris.c
@@ -984,7 +984,7 @@ void DrawSmashable_sprites(void)
 			object_matrix.m[2][1] = 0;
 			object_matrix.m[2][2] = ONE;
 
-			if ((model->shape_flags & SHAPE_FLAG_SMASH_SPRITE) == 0)
+			if ((model->shape_flags & SHAPE_FLAG_SPRITE) == 0)
 				RotMatrixY(dam->rot_speed * dam->damage * 3 & 0xfff, &object_matrix);
 
 			RotMatrixZ(dam->rot_speed * dam->damage & 0xfff, &object_matrix);
@@ -1006,7 +1006,7 @@ void DrawSmashable_sprites(void)
 
 			if (FrustrumCheck(&pos, model->bounding_sphere) != -1)
 			{
-				if (model->shape_flags & SHAPE_FLAG_SMASH_SPRITE)
+				if (model->shape_flags & SHAPE_FLAG_SPRITE)
 				{
 					UNIMPLEMENTED();
 
@@ -3633,7 +3633,7 @@ void AddRainDrops(void)
 		{
 			ROADS_GetRouteData(rt->position.vx, rt->position.vz, &routeData);
 
-			if (modelpointers[routeData.type]->flags2 & MODEL_FLAG_HASROOF)
+			if (modelpointers[routeData.type]->flags2 & MODEL_FLAG_INDOORS)
 				break;
 		}
 		*/
diff --git a/src_rebuild/Game/C/director.c b/src_rebuild/Game/C/director.c
index 99f2ebee..7a5df29c 100644
--- a/src_rebuild/Game/C/director.c
+++ b/src_rebuild/Game/C/director.c
@@ -1156,7 +1156,7 @@ void ControlReplay(void)
 			/*
 			ROADS_GetRouteData(player[0].cameraPos.vx, player[0].cameraPos.vz, &routeData1);
 
-			if (modelpointers[routeData1.type]->flags2 & MODEL_FLAG_HASROOF)
+			if (modelpointers[routeData1.type]->flags2 & MODEL_FLAG_INDOORS)
 			{
 				int road_height;
 				road_height = -450 - MapHeight(&player[0].cameraPos);
@@ -1291,7 +1291,7 @@ void ControlReplay(void)
 			/*
 			ROADS_GetRouteData(player[0].cameraPos.vx, player[0].cameraPos.vz, &routeData);
 
-			if ((modelpointers[routeData.type]->flags2 & MODEL_FLAG_HASROOF) && player[0].cameraPos.vy < height - 450)
+			if ((modelpointers[routeData.type]->flags2 & MODEL_FLAG_INDOORS) && player[0].cameraPos.vy < height - 450)
 			{
 				player[0].cameraPos.vy = height - 450;
 			}*/
diff --git a/src_rebuild/Game/C/draw.c b/src_rebuild/Game/C/draw.c
index 82b70b86..47428524 100644
--- a/src_rebuild/Game/C/draw.c
+++ b/src_rebuild/Game/C/draw.c
@@ -1416,7 +1416,7 @@ void DrawMapPSX(int* comp_val)
 					if (FrustrumCheck16(ppco, model->bounding_sphere) != -1)
 					{
 						// sprity type
-						if (model->shape_flags & SHAPE_FLAG_SMASH_SPRITE)
+						if (model->shape_flags & SHAPE_FLAG_SPRITE)
 						{
 							if (drawData.sprites_found < MAX_DRAWN_SPRITES)
 								spriteList[drawData.sprites_found++] = ppco;
@@ -1468,8 +1468,8 @@ void DrawMapPSX(int* comp_val)
 								}
 							}
 
-							if ((model->shape_flags & (SHAPE_FLAG_SUBSURFACE | SHAPE_FLAG_ALLEYWAY)) || 
-								(model->flags2 & (MODEL_FLAG_SIDEWALK | MODEL_FLAG_GRASS)))
+							if ((model->shape_flags & (SHAPE_FLAG_WATER | SHAPE_FLAG_TILE)) || 
+								(model->flags2 & (MODEL_FLAG_PATH | MODEL_FLAG_GRASS)))
 							{
 								if (model->flags2 & MODEL_FLAG_ALLEY)
 								{
diff --git a/src_rebuild/Game/C/objcoll.c b/src_rebuild/Game/C/objcoll.c
index 158838e0..329fefc2 100644
--- a/src_rebuild/Game/C/objcoll.c
+++ b/src_rebuild/Game/C/objcoll.c
@@ -49,7 +49,7 @@ char CellEmpty(VECTOR *pPosition, int radius)
 		pModel = modelpointers[type];
 
 		if ((uint)pModel->collision_block > 0 && 
-			(pModel->flags2 & (MODEL_FLAG_NOCOL_200 | MODEL_FLAG_SMASHABLE)) == 0)
+			(pModel->flags2 & (MODEL_FLAG_CHAIR | MODEL_FLAG_SMASHABLE)) == 0)
 		{
 			QuickUnpackCellObject(ppco, &ci.nearCell, &tempCO);
 
@@ -385,7 +385,7 @@ char lineClear(VECTOR *v1, VECTOR *v2)
 				sphere_sq = pModel->bounding_sphere + 800;
 
 				if ((uint)pModel->collision_block > 0 &&
-					(pModel->flags2 & (MODEL_FLAG_NOCOL_200 | MODEL_FLAG_SMASHABLE)) == 0 && 
+					(pModel->flags2 & (MODEL_FLAG_CHAIR | MODEL_FLAG_SMASHABLE)) == 0 && 
 					(xd*xd + zd*zd < sphere_sq*sphere_sq))
 				{
 					num_cb = *(int*)pModel->collision_block;
@@ -733,7 +733,7 @@ void CheckScenaryCollisions(CAR_DATA *cp)
 					}
 					else if (cp->controlType == CONTROL_TYPE_CAMERACOLLIDER)
 					{
-						if ((model->flags2 & (MODEL_FLAG_NOCOL_200 | MODEL_FLAG_SMASHABLE)) == 0 && 
+						if ((model->flags2 & (MODEL_FLAG_CHAIR | MODEL_FLAG_SMASHABLE)) == 0 && 
 							(bbox.xsize > 100 || (bbox.zsize > 100)))
 						{
 							coll_test_count = 5;
diff --git a/src_rebuild/Game/C/tile.c b/src_rebuild/Game/C/tile.c
index fa4eb0ba..4189c6cb 100644
--- a/src_rebuild/Game/C/tile.c
+++ b/src_rebuild/Game/C/tile.c
@@ -24,7 +24,7 @@ void Tile1x1(MODEL *model)
 	polys = (PL_POLYFT4*)model->poly_block;
 
 	// grass should be under pavements and other things
-	if ((model->shape_flags & SHAPE_FLAG_SUBSURFACE) || (model->flags2 & 0x4000))
+	if ((model->shape_flags & SHAPE_FLAG_WATER) || (model->flags2 & 0x4000))
 		ofse = 229;
 	else
 		ofse = 133;
@@ -416,7 +416,7 @@ void TileNxN(MODEL *model, int levels, int Dofse)
 	tileTypes = *(u_int *)(model + 1) >> 2;
 
 	// grass should be under pavements and other things
-	if((model->shape_flags & SHAPE_FLAG_SUBSURFACE) || (model->flags2 & 0x4000))
+	if((model->shape_flags & SHAPE_FLAG_WATER) || (model->flags2 & 0x4000))
 		ofse = 229;
 	else
 		ofse = 133;
diff --git a/src_rebuild/Game/dr2math.h b/src_rebuild/Game/dr2math.h
index 6552bd55..9c1dc858 100644
--- a/src_rebuild/Game/dr2math.h
+++ b/src_rebuild/Game/dr2math.h
@@ -22,6 +22,9 @@ extern short rcossin_tbl[8192];
 #define RSIN(a)			rcossin_tbl[(a & 0xFFFU) * 2]
 #define RCOS(a)			rcossin_tbl[(a & 0xFFFU) * 2 + 1]
 
+#define DIFF_ANGLES( A, B ) \
+	(((((B) - (A)) + 2048) & 4095) - 2048)
+
 // Remap a value in the range [A,B] to [C,D].
 #define RemapVal( val, A, B, C, D) \
 	(C + (D - C) * (val - A) / (B - A))
diff --git a/src_rebuild/Game/dr2types.h b/src_rebuild/Game/dr2types.h
index 4fb2abad..599afd4a 100644
--- a/src_rebuild/Game/dr2types.h
+++ b/src_rebuild/Game/dr2types.h
@@ -345,44 +345,55 @@ struct OUT_CELL_FILE_HEADER
 };
 
 //---------------------------------------------------------------------------------------
-// TODO: MODELS.H
+// TODO: MDL.H
 
 enum ModelShapeFlags
 {
-	SHAPE_FLAG_SMASH_QUIET		= 0x8,
+	SHAPE_FLAG_LITPOLY			= 0x1,
+	SHAPE_FLAG_BSPDATA			= 0x2,
+	SHAPE_FLAG_TRANS			= 0x8,
 	SHAPE_FLAG_NOCOLLIDE		= 0x10,
-	SHAPE_FLAG_SUBSURFACE		= 0x80,		// grass, dirt, water
-	SHAPE_FLAG_ALLEYWAY			= 0x400,	// alleyway
-	SHAPE_FLAG_SMASH_SPRITE		= 0x4000,
+	SHAPE_FLAG_WATER			= 0x80,		// model is water
+	SHAPE_FLAG_AMBIENT2			= 0x100,	// Ambient sound 2 associated - maybe used in D1
+	SHAPE_FLAG_AMBIENT1			= 0x200,	// Ambient sound 1 associated - maybe used in D1
+	SHAPE_FLAG_TILE				= 0x400,	// treat as road
+	SHAPE_FLAG_SHADOW			= 0x800,	// D1 leftover flag
+	SHAPE_FLAG_ALPHA			= 0x1000,	// alpha tested object
+	SHAPE_FLAG_ROAD				= 0x2000,	// section of road
+	SHAPE_FLAG_SPRITE			= 0x4000,
 };
 
 enum ModelFlags2
 {
-	MODEL_FLAG_ANIMOBJ			= 0x1,
-	MODEL_FLAG_MEDIAN			= 0x20,
-	MODEL_FLAG_ALLEY			= 0x80,
-	MODEL_FLAG_HASROOF			= 0x100,
-	MODEL_FLAG_NOCOL_200		= 0x200,
+	MODEL_FLAG_ANIMOBJ			= 0x1,		// CUSTOM FLAG!
+
+	MODEL_FLAG_MEDIAN			= 0x20,		// Hmmmm...
+	MODEL_FLAG_JUNC				= 0x40,
+	MODEL_FLAG_ALLEY			= 0x80,		// alley tile
+	MODEL_FLAG_INDOORS			= 0x100,
+	MODEL_FLAG_CHAIR			= 0x200,
 	MODEL_FLAG_BARRIER			= 0x400,
 	MODEL_FLAG_SMASHABLE		= 0x800,
 	MODEL_FLAG_LAMP				= 0x1000,
 	MODEL_FLAG_TREE				= 0x2000,
 	MODEL_FLAG_GRASS			= 0x4000,
-	MODEL_FLAG_SIDEWALK			= 0x8000,
+	MODEL_FLAG_PATH				= 0x8000,
 };
 
+#define COLLISION_BOX		0
+#define COLLISION_CYLINDER	1
+#define COLLISION_CONE		2
+#define COLLISION_SPHERE	3
+#define	COLLISION_INDOORS	4
+
 struct COLLISION_PACKET
 {
 	short type;
-	short xpos;
-	short ypos;
-	short zpos;
+	short xpos, ypos, zpos;
 	short flags;
 	short yang;
 	short empty;
-	short xsize;
-	short ysize;
-	short zsize;
+	short xsize, ysize, zsize;
 };
 
 struct POLYFT4
@@ -391,14 +402,8 @@ struct POLYFT4
 	u_char texture_set;
 	u_char texture_id;
 	u_char spare;
-	u_char v0;
-	u_char v1;
-	u_char v2;
-	u_char v3;
-	UV_INFO uv0;
-	UV_INFO uv1;
-	UV_INFO uv2;
-	UV_INFO uv3;
+	u_char v0, v1, v2, v3;
+	UV_INFO uv0, uv1, uv2, uv3;
 	RGB color;
 };
 
@@ -408,18 +413,9 @@ struct POLYGT4
 	u_char texture_set;
 	u_char texture_id;
 	u_char spare;
-	u_char v0;
-	u_char v1;
-	u_char v2;
-	u_char v3;
-	u_char n0;
-	u_char n1;
-	u_char n2;
-	u_char n3;
-	UV_INFO uv0;
-	UV_INFO uv1;
-	UV_INFO uv2;
-	UV_INFO uv3;
+	u_char v0, v1, v2, v3;
+	u_char n0, n1, n2, n3;
+	UV_INFO uv0, uv1, uv2, uv3;
 	RGB color;
 };
 
@@ -429,14 +425,8 @@ struct PL_POLYFT4
 	u_char texture_set;
 	u_char texture_id;
 	u_char th;
-	u_char v0;
-	u_char v1;
-	u_char v2;
-	u_char v3;
-	UV_INFO uv0;
-	UV_INFO uv1;
-	UV_INFO uv2;
-	UV_INFO uv3;
+	u_char v0, v1, v2, v3;
+	UV_INFO uv0, uv1, uv2, uv3;
 };
 
 
@@ -446,14 +436,8 @@ struct POLYFT3
 	u_char texture_set;
 	u_char texture_id;
 	u_char spare;
-	u_char v0;
-	u_char v1;
-	u_char v2;
-	u_char pad;
-	UV_INFO uv0;
-	UV_INFO uv1;
-	UV_INFO uv2;
-	UV_INFO pad2;
+	u_char v0, v1, v2, pad;
+	UV_INFO uv0, uv1, uv2, pad2;
 	RGB color;
 };
 
@@ -463,18 +447,9 @@ struct POLYGT3
 	u_char texture_set;
 	u_char texture_id;
 	u_char spare;
-	u_char v0;
-	u_char v1;
-	u_char v2;
-	u_char pad;
-	u_char n0;
-	u_char n1;
-	u_char n2;
-	u_char pad2;
-	UV_INFO uv0;
-	UV_INFO uv1;
-	UV_INFO uv2;
-	UV_INFO pad3;
+	u_char v0, v1, v2, pad;
+	u_char n0, n1, n2, pad2;
+	UV_INFO uv0, uv1, uv2, pad3;
 	RGB color;
 };