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diff --git a/public/disp_powerinfo.h b/public/disp_powerinfo.h
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+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: This module defines the CPowerInfo class, which contains a 
+//          whole bunch of precalculated data for each displacement power.
+//          It holds data that indicates how to tesselate, how to access
+//          neighbor displacements, etc.
+//
+// $NoKeywords: $
+//=============================================================================//
+
+#ifndef DISP_POWERINFO_H
+#define DISP_POWERINFO_H
+#ifdef _WIN32
+#pragma once
+#endif
+
+
+#include "disp_vertindex.h"
+#include "bspfile.h"
+
+
+#define NUM_POWERINFOS				(MAX_MAP_DISP_POWER+1)
+
+
+struct DispNodeInfo_t
+{
+	enum
+	{
+		// Indicates if any children at all have triangles
+		CHILDREN_HAVE_TRIANGLES = 0x1
+	};
+
+
+	// Indicates which tesselation indices are associated with a node
+	unsigned short	m_FirstTesselationIndex;
+	unsigned char	m_Count;
+	unsigned char	m_Flags;
+};
+
+
+// ------------------------------------------------------------------------ //
+// CTesselateWindings are used to tell what order a node needs to visit
+// vertices while tesselating.
+// ------------------------------------------------------------------------ //
+class CTesselateVert
+{
+public:
+				CTesselateVert( CVertIndex const &index, int iNode );
+
+	CVertIndex	m_Index;
+	short			m_iNode;	// Which node this vert is a part of (-1 on left, right, up, and down).
+};
+
+
+class CTesselateWinding
+{
+public:
+	CTesselateVert	*m_Verts;
+	short			m_nVerts;	// (includes the last vert)
+};
+
+
+class CVertDependency
+{
+public:
+	
+	// Returns false if there is no dependency stored here.
+	bool		IsValid()	{ return m_iVert.x != -1; }
+
+
+public:
+			
+	// The vert index is in the same power as the source displacement.
+	// It is also wrapped, so for example, on the middle of the right edge
+	// of a 3x3, it will have a dependency on the 3x3's root node (1,1), and it
+	// will have another (1,1) entry that references a neighbor.
+	CVertIndex	m_iVert;
+
+	// This is -1 if the vert exists inside the source displacement.
+	// It is one of the NEIGHBOREDGE_ codes above if it reaches into a neighbor.
+	short		m_iNeighbor;
+};
+
+
+// Precalculated data about displacement vertices.
+class CVertInfo
+{
+public:
+					CVertInfo();
+
+	// These are the vertices that this vertex depends on (vertices that must be 
+	// active for this vert to exist).
+	CVertDependency	m_Dependencies[2];
+
+	// These are the vertices that have this vert in their m_Dependencies.
+	enum			{ NUM_REVERSE_DEPENDENCIES=4 };
+	CVertDependency	m_ReverseDependencies[NUM_REVERSE_DEPENDENCIES];
+
+	short			m_iNodeLevel;		// -1 if this is not a node. Otherwise, the recursion level
+										// of this node (root node = 1).
+	CVertIndex		m_iParent;			// x=-1 if this is a not a node or if it's the root node.
+};
+
+
+class CTwoUShorts
+{
+public:
+	unsigned short	m_Values[2];
+};
+
+
+class CFourVerts
+{
+public:
+	CVertIndex		m_Verts[4];
+};
+
+
+// Used for referencing triangles in the fully-tesselated displacement by index.
+class CTriInfo
+{
+public:
+	unsigned short	m_Indices[3];
+};
+
+
+// Precalculated data for displacements of a certain power.
+class CPowerInfo
+{
+public:
+						CPowerInfo( 
+							CVertInfo *pVertInfo, 
+							CFourVerts *pSideVerts,
+							CFourVerts *pChildVerts,
+							CFourVerts *pSideVertCorners,
+							CTwoUShorts *pErrorEdges,
+							CTriInfo *pTriInfos );
+
+	int					GetPower() const		{ return m_Power; }
+	int					GetSideLength() const	{ return m_SideLength; }
+	const CVertIndex&	GetRootNode() const		{ return m_RootNode; }
+	int					GetMidPoint() const		{ return m_MidPoint; } // Half the edge length.
+
+	// Get at the tri list.
+	int					GetNumTriInfos() const		{ return m_nTriInfos; }
+	const CTriInfo*		GetTriInfo( int i ) const	{ return &m_pTriInfos[i]; }
+
+	// Get the number of vertices in a displacement of this power.
+	int					GetNumVerts() const			{ return m_MaxVerts; }
+	
+	// Return a corner point index. Indexed by the CORNER_ defines.
+	const CVertIndex&	GetCornerPointIndex( int iCorner ) const;
+
+
+public:
+
+	CVertInfo			*m_pVertInfo;
+	CFourVerts			*m_pSideVerts;	// The 4 side verts for each node.
+	CFourVerts			*m_pChildVerts;	// The 4 children for each node.
+	CFourVerts			*m_pSideVertCorners;
+	CTwoUShorts			*m_pErrorEdges;			// These are the edges
+												// that are used to measure the screenspace
+												// error with respect to each vert.
+
+	CTriInfo			*m_pTriInfos;
+	int					m_nTriInfos;
+	
+	int					m_Power;
+
+	CVertIndex			m_RootNode;
+	int					m_SideLength;
+	int					m_SideLengthM1;			// Side length minus 1.
+	int					m_MidPoint;				// Side length / 2.
+	int					m_MaxVerts;				// m_SideLength * m_SideLength
+	int					m_NodeCount;			// total # of nodes, including children
+
+	// Precalculated increments if you're using a bit vector to represent nodes.
+	// Starting at level 0 of the tree, this stores the increment between the nodes at this
+	// level. Vectors holding node data are stored in preorder traversal, and these
+	// increments tell the number of elements between nodes at each level.
+	int					m_NodeIndexIncrements[MAX_MAP_DISP_POWER];
+
+	CVertIndex			m_EdgeStartVerts[4];
+	CVertIndex			m_EdgeIncrements[4];
+
+	CVertIndex			m_NeighborStartVerts[4][4];	// [side][orientation]
+	CVertIndex			m_NeighborIncrements[4][4];	// [side][orientation]
+
+
+private:
+	friend void InitPowerInfo( CPowerInfo *pInfo, int iMaxPower );
+
+	CVertIndex			m_CornerPointIndices[4];
+};
+
+
+// ----------------------------------------------------------------------------- //
+// Globals.
+// ----------------------------------------------------------------------------- //
+
+// Indexed by the TWINDING_ enums.
+extern CTesselateWinding	g_TWinding;
+
+
+// ----------------------------------------------------------------------------- //
+// Functions.
+// ----------------------------------------------------------------------------- //
+
+// Valid indices are MIN_MAP_DISP_POWER through (and including) MAX_MAP_DISP_POWER.
+const CPowerInfo* GetPowerInfo( int iPower );
+
+
+#endif // DISP_POWERINFO_H