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1 files changed, 1080 insertions, 0 deletions

diff --git a/utils/vrad/vrad_dispcoll.cpp b/utils/vrad/vrad_dispcoll.cpp
new file mode 100644
index 0000000..2edd1ca
--- /dev/null
+++ b/utils/vrad/vrad_dispcoll.cpp
@@ -0,0 +1,1080 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+// $NoKeywords: $
+//=============================================================================//
+
+#include "vrad.h"
+#include "VRAD_DispColl.h"
+#include "DispColl_Common.h"
+#include "radial.h"
+#include "CollisionUtils.h"
+#include "tier0\dbg.h"
+
+#define SAMPLE_BBOX_SLOP		5.0f
+#define TRIEDGE_EPSILON			0.001f
+
+float g_flMaxDispSampleSize = 512.0f;
+
+static FileHandle_t pDispFile = FILESYSTEM_INVALID_HANDLE;
+
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+CVRADDispColl::CVRADDispColl()
+{
+	m_iParent = -1;
+
+	m_flSampleRadius2 = 0.0f;
+	m_flPatchSampleRadius2 = 0.0f;
+
+	m_flSampleWidth = 0.0f;
+	m_flSampleHeight = 0.0f;
+
+	m_aLuxelCoords.Purge();
+	m_aVertNormals.Purge();
+}
+	
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+CVRADDispColl::~CVRADDispColl()
+{
+	m_aLuxelCoords.Purge();
+	m_aVertNormals.Purge();
+}
+
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+bool CVRADDispColl::Create( CCoreDispInfo *pDisp )
+{
+	// Base class create.
+	if( !CDispCollTree::Create( pDisp ) )
+		return false;
+
+	// Allocate VRad specific memory.
+	m_aLuxelCoords.SetSize( GetSize() );
+	m_aVertNormals.SetSize( GetSize() );
+
+	// VRad specific base surface data.
+	CCoreDispSurface *pSurf = pDisp->GetSurface();
+	m_iParent = pSurf->GetHandle();
+
+	// VRad specific displacement surface data.
+	for ( int iVert = 0; iVert < m_aVerts.Count(); ++iVert )
+	{
+		pDisp->GetNormal( iVert, m_aVertNormals[iVert] );
+		pDisp->GetLuxelCoord( 0, iVert, m_aLuxelCoords[iVert] );
+	}
+
+	// Re-calculate the lightmap size (in uv) so that the luxels give
+	// a better world-space uniform approx. due to the non-linear nature
+	// of the displacement surface in uv-space
+	dface_t *pFace = &g_pFaces[m_iParent];
+	if( pFace )
+	{
+		CalcSampleRadius2AndBox( pFace );	
+	}
+
+	return true;
+}
+
+//-----------------------------------------------------------------------------
+// Purpose:
+//-----------------------------------------------------------------------------
+void CVRADDispColl::CalcSampleRadius2AndBox( dface_t *pFace )
+{
+	// Get the luxel sample size.
+	texinfo_t *pTexInfo = &texinfo[pFace->texinfo];
+	Assert ( pTexInfo );
+	if ( !pTexInfo )
+		return;
+
+	// Todo: Width = Height now, should change all the code to look at one value.
+	Vector vecTmp( pTexInfo->lightmapVecsLuxelsPerWorldUnits[0][0],
+		pTexInfo->lightmapVecsLuxelsPerWorldUnits[0][1],
+		pTexInfo->lightmapVecsLuxelsPerWorldUnits[0][2] );
+	float flWidth = 1.0f / VectorLength( vecTmp );
+	float flHeight = flWidth;
+	
+	// Save off the sample width and height.
+	m_flSampleWidth = flWidth;
+	m_flSampleHeight = flHeight;
+
+	// Calculate the sample radius squared.
+	float flSampleRadius = sqrt( ( ( flWidth * flWidth ) + ( flHeight * flHeight ) ) ) * 2.2f;//RADIALDIST2; 
+	if ( flSampleRadius > g_flMaxDispSampleSize )
+	{
+		flSampleRadius = g_flMaxDispSampleSize;
+	}
+	m_flSampleRadius2 = flSampleRadius * flSampleRadius;
+
+	// Calculate the patch radius - the max sample edge length * the number of luxels per edge "chop."
+	float flSampleSize = max( m_flSampleWidth, m_flSampleHeight );
+	float flPatchSampleRadius = flSampleSize * dispchop * 2.2f;
+	if ( flPatchSampleRadius > g_MaxDispPatchRadius )
+	{
+		flPatchSampleRadius = g_MaxDispPatchRadius;
+		Warning( "Patch Sample Radius Clamped!\n" );
+	}
+	m_flPatchSampleRadius2 = flPatchSampleRadius * flPatchSampleRadius;
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: Get the min/max of the displacement surface.
+//-----------------------------------------------------------------------------
+void CVRADDispColl::GetSurfaceMinMax( Vector &boxMin, Vector &boxMax )
+{
+	// Initialize the minimum and maximum box
+	boxMin = m_aVerts[0];
+	boxMax = m_aVerts[0];
+
+	for( int i = 1; i < m_aVerts.Count(); i++ )
+	{
+		if( m_aVerts[i].x < boxMin.x ) { boxMin.x = m_aVerts[i].x; }
+		if( m_aVerts[i].y < boxMin.y ) { boxMin.y = m_aVerts[i].y; }
+		if( m_aVerts[i].z < boxMin.z ) { boxMin.z = m_aVerts[i].z; }
+
+		if( m_aVerts[i].x > boxMax.x ) { boxMax.x = m_aVerts[i].x; }
+		if( m_aVerts[i].y > boxMax.y ) { boxMax.y = m_aVerts[i].y; }
+		if( m_aVerts[i].z > boxMax.z ) { boxMax.z = m_aVerts[i].z; }
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: Find the minor projection axes based on the given normal.
+//-----------------------------------------------------------------------------
+void CVRADDispColl::GetMinorAxes( Vector const &vecNormal, int &nAxis0, int &nAxis1 )
+{
+	nAxis0 = 0;
+	nAxis1 = 1;
+
+	if( FloatMakePositive( vecNormal.x ) > FloatMakePositive( vecNormal.y ) )
+	{
+		if( FloatMakePositive( vecNormal.x ) > FloatMakePositive( vecNormal.z ) )
+		{
+			nAxis0 = 1;
+			nAxis1 = 2;
+		}
+	}
+	else
+	{
+		if( FloatMakePositive( vecNormal.y ) > FloatMakePositive( vecNormal.z ) )
+		{
+			nAxis0 = 0;
+			nAxis1 = 2;
+		}
+	}
+}
+
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+void CVRADDispColl::BaseFacePlaneToDispUV( Vector const &vecPlanePt, Vector2D &dispUV )
+{
+	PointInQuadToBarycentric( m_vecSurfPoints[0], m_vecSurfPoints[3], m_vecSurfPoints[2], m_vecSurfPoints[1], vecPlanePt, dispUV );
+}
+
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+void CVRADDispColl::DispUVToSurfPoint( Vector2D const &dispUV, Vector &vecPoint, float flPushEps )
+{
+	// Check to see that the point is on the surface.
+	if ( dispUV.x < 0.0f || dispUV.x > 1.0f || dispUV.y < 0.0f || dispUV.y > 1.0f )
+		return;
+
+	// Get the displacement power.
+	int nWidth = ( ( 1 << m_nPower ) + 1 );
+	int nHeight = nWidth;
+
+	// Scale the U, V coordinates to the displacement grid size.
+	float flU = dispUV.x * static_cast<float>( nWidth - 1.000001f );
+	float flV = dispUV.y * static_cast<float>( nHeight - 1.000001f );
+
+	// Find the base U, V.
+	int nSnapU = static_cast<int>( flU );
+	int nSnapV = static_cast<int>( flV );
+
+	// Use this to get the triangle orientation.
+	bool bOdd = ( ( ( nSnapV * nWidth ) + nSnapU ) % 2 == 1 );
+
+	// Top Left to Bottom Right
+	if( bOdd )
+	{
+		DispUVToSurf_TriTLToBR( vecPoint, flPushEps, flU, flV, nSnapU, nSnapV, nWidth, nHeight );
+	}
+	// Bottom Left to Top Right
+	else
+	{
+		DispUVToSurf_TriBLToTR( vecPoint, flPushEps, flU, flV, nSnapU, nSnapV, nWidth, nHeight );
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Purpose:
+//-----------------------------------------------------------------------------
+void CVRADDispColl::DispUVToSurf_TriTLToBR( Vector &vecPoint, float flPushEps, 
+											float flU, float flV, int nSnapU, int nSnapV, 
+											int nWidth, int nHeight )
+{
+	int nNextU = nSnapU + 1;
+	int nNextV = nSnapV + 1;
+	if ( nNextU == nWidth)	 { --nNextU; }
+	if ( nNextV == nHeight ) { --nNextV; }
+
+	float flFracU = flU - static_cast<float>( nSnapU );
+	float flFracV = flV - static_cast<float>( nSnapV );
+
+	if( ( flFracU + flFracV ) >= ( 1.0f + TRIEDGE_EPSILON ) )
+	{
+		int nIndices[3];
+		nIndices[0] = nNextV * nWidth + nSnapU;
+		nIndices[1] = nNextV * nWidth + nNextU;	
+		nIndices[2] = nSnapV * nWidth + nNextU;
+
+		Vector edgeU = m_aVerts[nIndices[0]] - m_aVerts[nIndices[1]];
+		Vector edgeV = m_aVerts[nIndices[2]] - m_aVerts[nIndices[1]];
+		vecPoint = m_aVerts[nIndices[1]] + edgeU * ( 1.0f - flFracU ) + edgeV * ( 1.0f - flFracV );
+
+		if ( flPushEps != 0.0f )
+		{
+			Vector vecNormal;
+			vecNormal = CrossProduct( edgeU, edgeV );
+			VectorNormalize( vecNormal );
+			vecPoint += ( vecNormal * flPushEps );
+		}
+	}
+	else
+	{
+		int nIndices[3];
+		nIndices[0] = nSnapV * nWidth + nSnapU;
+		nIndices[1] = nNextV * nWidth + nSnapU;
+		nIndices[2] = nSnapV * nWidth + nNextU;
+
+		Vector edgeU = m_aVerts[nIndices[2]] - m_aVerts[nIndices[0]];
+		Vector edgeV = m_aVerts[nIndices[1]] - m_aVerts[nIndices[0]];
+		vecPoint = m_aVerts[nIndices[0]] + edgeU * flFracU + edgeV * flFracV;
+
+		if ( flPushEps != 0.0f )
+		{
+			Vector vecNormal;
+			vecNormal = CrossProduct( edgeU, edgeV );
+			VectorNormalize( vecNormal );
+			vecPoint += ( vecNormal * flPushEps );
+		}
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Purpose:
+//-----------------------------------------------------------------------------
+void CVRADDispColl::DispUVToSurf_TriBLToTR( Vector &vecPoint, float flPushEps, 
+											float flU, float flV, int nSnapU, int nSnapV, 
+											int nWidth, int nHeight )
+{
+	int nNextU = nSnapU + 1;
+	int nNextV = nSnapV + 1;
+	if ( nNextU == nWidth)	 { --nNextU; }
+	if ( nNextV == nHeight ) { --nNextV; }
+
+	float flFracU = flU - static_cast<float>( nSnapU );
+	float flFracV = flV - static_cast<float>( nSnapV );
+
+	if( flFracU < flFracV )
+	{
+		int nIndices[3];
+		nIndices[0] = nSnapV * nWidth + nSnapU;
+		nIndices[1] = nNextV * nWidth + nSnapU;
+		nIndices[2] = nNextV * nWidth + nNextU;
+
+		Vector edgeU = m_aVerts[nIndices[2]] - m_aVerts[nIndices[1]];
+		Vector edgeV = m_aVerts[nIndices[0]] - m_aVerts[nIndices[1]];
+		vecPoint =  m_aVerts[nIndices[1]] + edgeU * flFracU + edgeV * ( 1.0f - flFracV );
+
+		if ( flPushEps != 0.0f )
+		{
+			Vector vecNormal;
+			vecNormal = CrossProduct( edgeV, edgeU );
+			VectorNormalize( vecNormal );
+			vecPoint += ( vecNormal * flPushEps );
+		}
+	}
+	else
+	{
+		int nIndices[3];
+		nIndices[0] = nSnapV * nWidth + nSnapU;
+		nIndices[1] = nNextV * nWidth + nNextU;
+		nIndices[2] = nSnapV * nWidth + nNextU;
+
+		Vector edgeU = m_aVerts[nIndices[0]] - m_aVerts[nIndices[2]];
+		Vector edgeV = m_aVerts[nIndices[1]] - m_aVerts[nIndices[2]];
+		vecPoint = m_aVerts[nIndices[2]] + edgeU * ( 1.0f - flFracU ) + edgeV * flFracV;
+
+		if ( flPushEps != 0.0f )
+		{
+			Vector vecNormal;
+			vecNormal = CrossProduct( edgeV, edgeU );
+			VectorNormalize( vecNormal );
+			vecPoint += ( vecNormal * flPushEps );
+		}
+	}
+}
+
+//-----------------------------------------------------------------------------
+//-----------------------------------------------------------------------------
+void CVRADDispColl::DispUVToSurfNormal( Vector2D const &dispUV, Vector &vecNormal )
+{
+	// Check to see that the point is on the surface.
+	if ( dispUV.x < 0.0f || dispUV.x > 1.0f || dispUV.y < 0.0f || dispUV.y > 1.0f )
+		return;
+
+	// Get the displacement power.
+	int nWidth = ( ( 1 << m_nPower ) + 1 );
+	int nHeight = nWidth;
+
+	// Scale the U, V coordinates to the displacement grid size.
+	float flU = dispUV.x * static_cast<float>( nWidth - 1.000001f );
+	float flV = dispUV.y * static_cast<float>( nHeight - 1.000001f );
+
+	// Find the base U, V.
+	int nSnapU = static_cast<int>( flU );
+	int nSnapV = static_cast<int>( flV );
+
+	int nNextU = nSnapU + 1;
+	int nNextV = nSnapV + 1;
+	if ( nNextU == nWidth)	 { --nNextU; }
+	if ( nNextV == nHeight ) { --nNextV; }
+
+	float flFracU = flU - static_cast<float>( nSnapU );
+	float flFracV = flV - static_cast<float>( nSnapV );
+
+	// Get the four normals "around" the "spot"
+	int iQuad[VRAD_QUAD_SIZE];
+	iQuad[0] = ( nSnapV * nWidth ) + nSnapU;
+	iQuad[1] = ( nNextV * nWidth ) + nSnapU;
+	iQuad[2] = ( nNextV * nWidth ) + nNextU;
+	iQuad[3] = ( nSnapV * nWidth ) + nNextU;
+
+	// Find the blended normal (bi-linear).
+	Vector vecTmpNormals[2], vecBlendedNormals[2], vecDispNormals[4];
+	
+	for ( int iVert = 0; iVert < VRAD_QUAD_SIZE; ++iVert )
+	{
+		GetVertNormal( iQuad[iVert], vecDispNormals[iVert] );
+	}
+
+	vecTmpNormals[0] = vecDispNormals[0] * ( 1.0f - flFracU );
+	vecTmpNormals[1] = vecDispNormals[3] * flFracU;
+	vecBlendedNormals[0] = vecTmpNormals[0] + vecTmpNormals[1];
+	VectorNormalize( vecBlendedNormals[0] );
+
+	vecTmpNormals[0] = vecDispNormals[1] * ( 1.0f - flFracU );
+	vecTmpNormals[1] = vecDispNormals[2] * flFracU;
+	vecBlendedNormals[1] = vecTmpNormals[0] + vecTmpNormals[1];
+	VectorNormalize( vecBlendedNormals[1] );
+
+	vecTmpNormals[0] = vecBlendedNormals[0] * ( 1.0f - flFracV );
+	vecTmpNormals[1] = vecBlendedNormals[1] * flFracV;
+
+	vecNormal = vecTmpNormals[0] + vecTmpNormals[1];
+	VectorNormalize( vecNormal );
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Output : float
+//-----------------------------------------------------------------------------
+float CVRADDispColl::CreateParentPatches( void )
+{
+	// Save the total surface area of the displacement.
+	float flTotalArea = 0.0f;
+
+	// Get the number of displacement subdivisions.
+	int nInterval = GetWidth();
+
+	Vector vecPoints[4];
+	vecPoints[0].Init( m_aVerts[0].x, m_aVerts[0].y, m_aVerts[0].z );
+	vecPoints[1].Init( m_aVerts[(nInterval*(nInterval-1))].x, m_aVerts[(nInterval*(nInterval-1))].y, m_aVerts[(nInterval*(nInterval-1))].z );
+	vecPoints[2].Init( m_aVerts[((nInterval*nInterval)-1)].x, m_aVerts[((nInterval*nInterval)-1)].y, m_aVerts[((nInterval*nInterval)-1)].z );
+	vecPoints[3].Init( m_aVerts[(nInterval-1)].x, m_aVerts[(nInterval-1)].y, m_aVerts[(nInterval-1)].z );
+
+	// Create and initialize the patch.
+	int iPatch = g_Patches.AddToTail();
+	if ( iPatch == g_Patches.InvalidIndex() )
+		return flTotalArea;
+
+	// Keep track of the area of the patches.
+	float flArea = 0.0f;
+	if ( !InitParentPatch( iPatch, vecPoints, flArea ) )
+	{
+		g_Patches.Remove( iPatch );
+		flArea = 0.0f;
+	}
+
+	// Return the displacement area.
+	return flArea;
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Input  : iParentPatch - 
+//			nLevel - 
+//-----------------------------------------------------------------------------
+void CVRADDispColl::CreateChildPatchesFromRoot( int iParentPatch, int *pChildPatch )
+{
+	// Initialize the child patch indices.
+	pChildPatch[0] = g_Patches.InvalidIndex();
+	pChildPatch[1] = g_Patches.InvalidIndex();
+
+	// Get the number of displacement subdivisions.
+	int nInterval = GetWidth();
+
+	// Get the parent patch.
+	CPatch *pParentPatch = &g_Patches[iParentPatch];
+	if ( !pParentPatch )
+		return;
+
+	// Split along the longest edge.
+	Vector vecEdges[4];
+	vecEdges[0] = pParentPatch->winding->p[1] - pParentPatch->winding->p[0];
+	vecEdges[1] = pParentPatch->winding->p[2] - pParentPatch->winding->p[1];
+	vecEdges[2] = pParentPatch->winding->p[3] - pParentPatch->winding->p[2];
+	vecEdges[3] = pParentPatch->winding->p[3] - pParentPatch->winding->p[0];
+
+	// Should the patch be subdivided - check the area.
+	float flMaxLength  = max( m_flSampleWidth, m_flSampleHeight );
+	float flMinEdgeLength = flMaxLength * dispchop;
+
+	// Find the longest edge.
+	float flEdgeLength = 0.0f;
+	int iLongEdge = -1;
+	for ( int iEdge = 0; iEdge < 4; ++iEdge )
+	{
+		float flLength = vecEdges[iEdge].Length();
+		if ( flEdgeLength < flLength )
+		{
+			flEdgeLength = vecEdges[iEdge].Length();
+			iLongEdge = iEdge;
+		}
+	}
+
+	// Small enough already, return.
+	if ( flEdgeLength < flMinEdgeLength )
+		return;
+
+	// Test area as well so we don't allow slivers.
+	float flMinArea = ( dispchop * flMaxLength ) * ( dispchop * flMaxLength );
+	Vector vecNormal = vecEdges[3].Cross( vecEdges[0] );
+	float flTestArea = VectorNormalize( vecNormal );
+	if ( flTestArea < flMinArea )
+		return;
+
+	// Get the points for the first triangle.
+	int iPoints[3];
+	Vector vecPoints[3];
+	float flArea;
+
+	iPoints[0] = ( nInterval * nInterval ) - 1;
+	iPoints[1] = 0;
+	iPoints[2] = nInterval * ( nInterval - 1 );
+	for ( int iPoint = 0; iPoint < 3; ++iPoint )
+	{
+		VectorCopy( m_aVerts[iPoints[iPoint]], vecPoints[iPoint] );
+	}
+
+	// Create and initialize the patch.
+	pChildPatch[0] = g_Patches.AddToTail();
+	if ( pChildPatch[0] == g_Patches.InvalidIndex() )
+		return;
+
+	if ( !InitPatch( pChildPatch[0], iParentPatch, 0, vecPoints, iPoints, flArea ) )
+	{
+		g_Patches.Remove( pChildPatch[0] );
+		pChildPatch[0] = g_Patches.InvalidIndex();
+		return;
+	}
+
+	// Get the points for the second triangle.
+	iPoints[0] = 0;
+	iPoints[1] = ( nInterval * nInterval ) - 1;
+	iPoints[2] = nInterval - 1;
+	for ( int iPoint = 0; iPoint < 3; ++iPoint )
+	{
+		VectorCopy( m_aVerts[iPoints[iPoint]], vecPoints[iPoint] );
+	}
+
+	// Create and initialize the patch.
+	pChildPatch[1] = g_Patches.AddToTail();
+	if ( pChildPatch[1] == g_Patches.InvalidIndex() )
+	{
+		g_Patches.Remove( pChildPatch[0] );
+		pChildPatch[0] = g_Patches.InvalidIndex();
+		return;
+	}
+
+	if ( !InitPatch( pChildPatch[1], iParentPatch, 1, vecPoints, iPoints, flArea ) )
+	{
+		g_Patches.Remove( pChildPatch[0] );
+		pChildPatch[0] = g_Patches.InvalidIndex();
+		g_Patches.Remove( pChildPatch[1] );
+		pChildPatch[1] = g_Patches.InvalidIndex();
+		return;
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Input  : flMinArea - 
+// Output : float
+//-----------------------------------------------------------------------------
+void CVRADDispColl::CreateChildPatches( int iParentPatch, int nLevel )
+{
+	// Get the parent patch.
+	CPatch *pParentPatch = &g_Patches[iParentPatch];
+	if ( !pParentPatch )
+		return;
+
+	// The root face is a quad - special case.
+	if ( pParentPatch->winding->numpoints == 4 )
+	{
+		int iChildPatch[2];
+		CreateChildPatchesFromRoot( iParentPatch, iChildPatch );
+		if ( iChildPatch[0] != g_Patches.InvalidIndex() && iChildPatch[1] != g_Patches.InvalidIndex() )
+		{
+			CreateChildPatches( iChildPatch[0], 0 );
+			CreateChildPatches( iChildPatch[1], 0 );
+		}
+		return;
+	}
+
+	// Calculate the the area of the patch (triangle!).
+	Assert( pParentPatch->winding->numpoints == 3 );
+	if ( pParentPatch->winding->numpoints != 3 )
+		return;
+
+	// Should the patch be subdivided - check the area.
+	float flMaxLength  = max( m_flSampleWidth, m_flSampleHeight );
+	float flMinEdgeLength = flMaxLength * dispchop;
+
+	// Split along the longest edge.
+	Vector vecEdges[3];
+	vecEdges[0] = pParentPatch->winding->p[1] - pParentPatch->winding->p[0];
+	vecEdges[1] = pParentPatch->winding->p[2] - pParentPatch->winding->p[0];
+	vecEdges[2] = pParentPatch->winding->p[2] - pParentPatch->winding->p[1];
+
+	// Find the longest edge.
+	float flEdgeLength = 0.0f;
+	int iLongEdge = -1;
+	for ( int iEdge = 0; iEdge < 3; ++iEdge )
+	{
+		if ( flEdgeLength < vecEdges[iEdge].Length() )
+		{
+			flEdgeLength = vecEdges[iEdge].Length();
+			iLongEdge = iEdge;
+		}
+	}
+
+	// Small enough already, return.
+	if ( flEdgeLength < flMinEdgeLength )
+		return;
+
+	// Test area as well so we don't allow slivers.
+	float flMinArea = ( dispchop * flMaxLength ) * ( dispchop * flMaxLength ) * 0.5f;
+	Vector vecNormal = vecEdges[1].Cross( vecEdges[0] );
+	float flTestArea = VectorNormalize( vecNormal );
+	flTestArea *= 0.5f;
+	if ( flTestArea < flMinArea )
+		return;
+
+	// Check to see if any more displacement verts exist - go to subdivision if not.
+	if ( nLevel >= ( m_nPower * 2 ) )
+	{
+		CreateChildPatchesSub( iParentPatch );
+		return;
+	}
+
+	int nChildIndices[2][3];
+	int nNewIndex = ( pParentPatch->indices[1] + pParentPatch->indices[0] ) / 2;
+	nChildIndices[0][0] = pParentPatch->indices[2];
+	nChildIndices[0][1] = pParentPatch->indices[0];
+	nChildIndices[0][2] = nNewIndex;
+
+	nChildIndices[1][0] = pParentPatch->indices[1];
+	nChildIndices[1][1] = pParentPatch->indices[2];
+	nChildIndices[1][2] = nNewIndex;
+
+	Vector vecChildPoints[2][3];
+	for ( int iTri = 0; iTri < 2; ++iTri )
+	{
+		for ( int iPoint = 0; iPoint < 3; ++iPoint )
+		{
+			VectorCopy( m_aVerts[nChildIndices[iTri][iPoint]], vecChildPoints[iTri][iPoint] );
+		}
+	}
+
+	// Create and initialize the children patches.
+	int iChildPatch[2] = { -1, -1 };
+	for ( int iChild = 0; iChild < 2; ++iChild )
+	{
+		iChildPatch[iChild] = g_Patches.AddToTail();
+
+		float flArea = 0.0f;
+		if ( !InitPatch( iChildPatch[iChild], iParentPatch, iChild, vecChildPoints[iChild], nChildIndices[iChild], flArea ) )
+		{
+			if ( iChild == 0 )
+			{
+				pParentPatch->child1 = g_Patches.InvalidIndex();
+				g_Patches.Remove( iChildPatch[iChild] );
+				break;
+			}
+			else
+			{
+				pParentPatch->child1 = g_Patches.InvalidIndex();
+				pParentPatch->child2 = g_Patches.InvalidIndex();
+				g_Patches.Remove( iChildPatch[iChild] );
+				g_Patches.Remove( iChildPatch[0] );
+			}
+		}
+	}
+	
+	// Continue creating children patches.
+	int nNewLevel = ++nLevel;
+	CreateChildPatches( iChildPatch[0], nNewLevel );
+	CreateChildPatches( iChildPatch[1], nNewLevel );
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Input  : flMinArea - 
+// Output : float
+//-----------------------------------------------------------------------------
+void CVRADDispColl::CreateChildPatchesSub( int iParentPatch )
+{
+	// Get the parent patch.
+	CPatch *pParentPatch = &g_Patches[iParentPatch];
+	if ( !pParentPatch )
+		return;
+
+	// Calculate the the area of the patch (triangle!).
+	Assert( pParentPatch->winding->numpoints == 3 );
+	if ( pParentPatch->winding->numpoints != 3 )
+		return;
+
+	// Should the patch be subdivided - check the area.
+	float flMaxLength  = max( m_flSampleWidth, m_flSampleHeight );
+	float flMinEdgeLength = flMaxLength * dispchop;
+
+	// Split along the longest edge.
+	Vector vecEdges[3];
+	vecEdges[0] = pParentPatch->winding->p[1] - pParentPatch->winding->p[0];
+	vecEdges[1] = pParentPatch->winding->p[2] - pParentPatch->winding->p[1];
+	vecEdges[2] = pParentPatch->winding->p[0] - pParentPatch->winding->p[2];
+
+	// Find the longest edge.
+	float flEdgeLength = 0.0f;
+	int iLongEdge = -1;
+	for ( int iEdge = 0; iEdge < 3; ++iEdge )
+	{
+		if ( flEdgeLength < vecEdges[iEdge].Length() )
+		{
+			flEdgeLength = vecEdges[iEdge].Length();
+			iLongEdge = iEdge;
+		}
+	}
+
+	// Small enough already, return.
+	if ( flEdgeLength < flMinEdgeLength )
+		return;
+
+	// Test area as well so we don't allow slivers.
+	float flMinArea = ( dispchop * flMaxLength ) * ( dispchop * flMaxLength ) * 0.5f;
+	Vector vecNormal = vecEdges[1].Cross( vecEdges[0] );
+	float flTestArea = VectorNormalize( vecNormal );
+	flTestArea *= 0.5f;
+	if ( flTestArea < flMinArea )
+		return;
+
+	// Create children patchs - 2 of them.
+	Vector vecChildPoints[2][3];
+	switch ( iLongEdge )
+	{
+	case 0:
+		{
+			vecChildPoints[0][0] = pParentPatch->winding->p[0];
+			vecChildPoints[0][1] = ( pParentPatch->winding->p[0] + pParentPatch->winding->p[1] ) * 0.5f;
+			vecChildPoints[0][2] = pParentPatch->winding->p[2];
+
+			vecChildPoints[1][0] = ( pParentPatch->winding->p[0] + pParentPatch->winding->p[1] ) * 0.5f;
+			vecChildPoints[1][1] = pParentPatch->winding->p[1];
+			vecChildPoints[1][2] = pParentPatch->winding->p[2];
+			break;
+		}
+	case 1:
+		{
+			vecChildPoints[0][0] = pParentPatch->winding->p[0];
+			vecChildPoints[0][1] = pParentPatch->winding->p[1];
+			vecChildPoints[0][2] = ( pParentPatch->winding->p[1] + pParentPatch->winding->p[2] ) * 0.5f;
+
+			vecChildPoints[1][0] = ( pParentPatch->winding->p[1] + pParentPatch->winding->p[2] ) * 0.5f;
+			vecChildPoints[1][1] = pParentPatch->winding->p[2];
+			vecChildPoints[1][2] = pParentPatch->winding->p[0];
+			break;
+		}
+	case 2:
+		{
+			vecChildPoints[0][0] = pParentPatch->winding->p[0];
+			vecChildPoints[0][1] = pParentPatch->winding->p[1];
+			vecChildPoints[0][2] = ( pParentPatch->winding->p[0] + pParentPatch->winding->p[2] ) * 0.5f;
+
+			vecChildPoints[1][0] = ( pParentPatch->winding->p[0] + pParentPatch->winding->p[2] ) * 0.5f;
+			vecChildPoints[1][1] = pParentPatch->winding->p[1];
+			vecChildPoints[1][2] = pParentPatch->winding->p[2];
+			break;
+		}
+	}
+
+
+	// Create and initialize the children patches.
+	int iChildPatch[2] = { 0, 0 };
+	int nChildIndices[3] = { -1, -1, -1 };
+	for ( int iChild = 0; iChild < 2; ++iChild )
+	{
+		iChildPatch[iChild] = g_Patches.AddToTail();
+
+		float flArea = 0.0f;
+		if ( !InitPatch( iChildPatch[iChild], iParentPatch, iChild, vecChildPoints[iChild], nChildIndices, flArea ) )
+		{
+			if ( iChild == 0 )
+			{
+				pParentPatch->child1 = g_Patches.InvalidIndex();
+				g_Patches.Remove( iChildPatch[iChild] );
+				break;
+			}
+			else
+			{
+				pParentPatch->child1 = g_Patches.InvalidIndex();
+				pParentPatch->child2 = g_Patches.InvalidIndex();
+				g_Patches.Remove( iChildPatch[iChild] );
+				g_Patches.Remove( iChildPatch[0] );
+			}
+		}
+	}
+	
+	// Continue creating children patches.
+	CreateChildPatchesSub( iChildPatch[0] );
+	CreateChildPatchesSub( iChildPatch[1] );
+}
+
+int	PlaneTypeForNormal (Vector& normal)
+{
+	vec_t	ax, ay, az;
+
+	// NOTE: should these have an epsilon around 1.0?		
+	if (normal[0] == 1.0 || normal[0] == -1.0)
+		return PLANE_X;
+	if (normal[1] == 1.0 || normal[1] == -1.0)
+		return PLANE_Y;
+	if (normal[2] == 1.0 || normal[2] == -1.0)
+		return PLANE_Z;
+
+	ax = fabs(normal[0]);
+	ay = fabs(normal[1]);
+	az = fabs(normal[2]);
+
+	if (ax >= ay && ax >= az)
+		return PLANE_ANYX;
+	if (ay >= ax && ay >= az)
+		return PLANE_ANYY;
+	return PLANE_ANYZ;
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Input  : iPatch - 
+//			iParentPatch - 
+//			iChild - 
+//			*pPoints - 
+//			*pIndices - 
+//			&flArea - 
+// Output : Returns true on success, false on failure.
+//-----------------------------------------------------------------------------
+bool CVRADDispColl::InitParentPatch( int iPatch, Vector *pPoints, float &flArea )
+{
+	// Get the current patch.
+	CPatch *pPatch = &g_Patches[iPatch];
+	if ( !pPatch )
+		return false;
+
+	// Clear the patch data.
+	memset( pPatch, 0, sizeof( CPatch ) );
+
+	// This is a parent.
+	pPatch->ndxNext = g_FacePatches.Element( GetParentIndex() );
+	g_FacePatches[GetParentIndex()] = iPatch;
+	pPatch->faceNumber = GetParentIndex();
+
+	// Initialize parent and children indices.
+	pPatch->child1 = g_Patches.InvalidIndex();
+	pPatch->child2 = g_Patches.InvalidIndex();
+	pPatch->parent = g_Patches.InvalidIndex();
+	pPatch->ndxNextClusterChild = g_Patches.InvalidIndex();
+	pPatch->ndxNextParent = g_Patches.InvalidIndex();
+
+	Vector vecEdges[2];
+	vecEdges[0] = pPoints[1] - pPoints[0];
+	vecEdges[1] = pPoints[3] - pPoints[0];
+
+	// Calculate the triangle normal and area.
+	Vector vecNormal = vecEdges[1].Cross( vecEdges[0] );
+	flArea = VectorNormalize( vecNormal );
+
+	// Initialize the patch scale.
+	pPatch->scale[0] = pPatch->scale[1] = 1.0f;
+
+	// Set the patch chop - minchop (that is what the minimum area is based on).
+	pPatch->chop = dispchop;
+
+	// Displacements are not sky!
+	pPatch->sky = false;
+
+	// Copy the winding.
+	Vector vecCenter( 0.0f, 0.0f, 0.0f );
+	pPatch->winding = AllocWinding( 4 );
+	pPatch->winding->numpoints = 4;
+	for ( int iPoint = 0; iPoint < 4; ++iPoint )
+	{
+		VectorCopy( pPoints[iPoint], pPatch->winding->p[iPoint] );
+		VectorAdd( pPoints[iPoint], vecCenter, vecCenter );
+	}
+
+	// Set the origin and normal.
+	VectorScale( vecCenter, ( 1.0f / 4.0f ), vecCenter );
+	VectorCopy( vecCenter, pPatch->origin );
+	VectorCopy( vecNormal, pPatch->normal );
+
+	// Create the plane.
+	pPatch->plane = new dplane_t;
+	if ( !pPatch->plane )
+		return false;
+
+	VectorCopy( vecNormal, pPatch->plane->normal );
+	pPatch->plane->dist = vecNormal.Dot( pPoints[0] );
+	pPatch->plane->type = PlaneTypeForNormal( pPatch->plane->normal );
+	pPatch->planeDist = pPatch->plane->dist;
+
+	// Set the area.
+	pPatch->area = flArea;
+
+	// Calculate the mins/maxs.
+	Vector vecMin( FLT_MAX, FLT_MAX, FLT_MAX );
+	Vector vecMax( FLT_MIN, FLT_MIN, FLT_MIN );
+	for ( int iPoint = 0; iPoint < 4; ++iPoint )
+	{
+		for ( int iAxis = 0; iAxis < 3; ++iAxis )
+		{
+			vecMin[iAxis] = min( vecMin[iAxis], pPoints[iPoint][iAxis] );
+			vecMax[iAxis] = max( vecMax[iAxis], pPoints[iPoint][iAxis] );
+		}
+	}
+
+	VectorCopy( vecMin, pPatch->mins );
+	VectorCopy( vecMax, pPatch->maxs );
+	VectorCopy( vecMin, pPatch->face_mins );
+	VectorCopy( vecMax, pPatch->face_maxs );
+
+	// Check for bumpmap.
+	dface_t *pFace = dfaces + pPatch->faceNumber;
+	texinfo_t *pTexInfo = &texinfo[pFace->texinfo];
+	pPatch->needsBumpmap = pTexInfo->flags & SURF_BUMPLIGHT ? true : false;
+
+	// Misc...
+	pPatch->m_IterationKey = 0;
+
+	// Calculate the base light, area, and reflectivity.
+	BaseLightForFace( &g_pFaces[pPatch->faceNumber], pPatch->baselight, &pPatch->basearea, pPatch->reflectivity );
+
+	return true;
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: 
+// Input  : *pPatch - 
+//			*pPoints - 
+//			&vecNormal - 
+//			flArea - 
+//-----------------------------------------------------------------------------
+bool CVRADDispColl::InitPatch( int iPatch, int iParentPatch, int iChild, Vector *pPoints, int *pIndices, float &flArea )
+{
+	// Get the current patch.
+	CPatch *pPatch = &g_Patches[iPatch];
+	if ( !pPatch )
+		return false;
+
+	// Clear the patch data.
+	memset( pPatch, 0, sizeof( CPatch ) );
+
+	// Setup the parent if we are not the parent.
+	CPatch *pParentPatch = NULL;
+	if ( iParentPatch != g_Patches.InvalidIndex() )
+	{
+		// Get the parent patch.
+		pParentPatch = &g_Patches[iParentPatch];
+		if ( !pParentPatch )
+			return false;
+	}
+
+	// Attach the face to the correct lists.
+	if ( !pParentPatch )
+	{
+		// This is a parent.
+		pPatch->ndxNext = g_FacePatches.Element( GetParentIndex() );
+		g_FacePatches[GetParentIndex()] = iPatch;
+		pPatch->faceNumber = GetParentIndex();
+	}
+	else
+	{
+		pPatch->ndxNext = g_Patches.InvalidIndex();
+		pPatch->faceNumber = pParentPatch->faceNumber;
+
+		// Attach to the parent patch.
+		if ( iChild == 0 )
+		{
+			pParentPatch->child1 = iPatch;
+		}
+		else
+		{
+			pParentPatch->child2 = iPatch;
+		}
+	}
+
+	// Initialize parent and children indices.
+	pPatch->child1 = g_Patches.InvalidIndex();
+	pPatch->child2 = g_Patches.InvalidIndex();
+	pPatch->ndxNextClusterChild = g_Patches.InvalidIndex();
+	pPatch->ndxNextParent = g_Patches.InvalidIndex();
+	pPatch->parent = iParentPatch;
+
+	// Get triangle edges.
+	Vector vecEdges[3];
+	vecEdges[0] = pPoints[1] - pPoints[0];
+	vecEdges[1] = pPoints[2] - pPoints[0];
+	vecEdges[2] = pPoints[2] - pPoints[1];
+
+	// Find the longest edge.
+//	float flEdgeLength = 0.0f;
+//	for ( int iEdge = 0; iEdge < 3; ++iEdge )
+//	{
+//		if ( flEdgeLength < vecEdges[iEdge].Length() )
+//		{
+//			flEdgeLength = vecEdges[iEdge].Length();
+//		}
+//	}
+
+	// Calculate the triangle normal and area.
+	Vector vecNormal = vecEdges[1].Cross( vecEdges[0] );
+	flArea = VectorNormalize( vecNormal );
+	flArea *= 0.5f;
+
+	// Initialize the patch scale.
+	pPatch->scale[0] = pPatch->scale[1] = 1.0f;
+
+	// Set the patch chop - minchop (that is what the minimum area is based on).
+	pPatch->chop = dispchop;
+
+	// Displacements are not sky!
+	pPatch->sky = false;
+
+	// Copy the winding.
+	Vector vecCenter( 0.0f, 0.0f, 0.0f );
+	pPatch->winding = AllocWinding( 3 );
+	pPatch->winding->numpoints = 3;
+	for ( int iPoint = 0; iPoint < 3; ++iPoint )
+	{
+		VectorCopy( pPoints[iPoint], pPatch->winding->p[iPoint] );
+		VectorAdd( pPoints[iPoint], vecCenter, vecCenter );
+
+		pPatch->indices[iPoint] = static_cast<short>( pIndices[iPoint] );
+	}
+
+	// Set the origin and normal.
+	VectorScale( vecCenter, ( 1.0f / 3.0f ), vecCenter );
+	VectorCopy( vecCenter, pPatch->origin );
+	VectorCopy( vecNormal, pPatch->normal );
+
+	// Create the plane.
+	pPatch->plane = new dplane_t;
+	if ( !pPatch->plane )
+		return false;
+
+	VectorCopy( vecNormal, pPatch->plane->normal );
+	pPatch->plane->dist = vecNormal.Dot( pPoints[0] );
+	pPatch->plane->type = PlaneTypeForNormal( pPatch->plane->normal );
+	pPatch->planeDist = pPatch->plane->dist;
+
+	// Set the area.
+	pPatch->area = flArea;
+
+	// Calculate the mins/maxs.
+	Vector vecMin( FLT_MAX, FLT_MAX, FLT_MAX );
+	Vector vecMax( FLT_MIN, FLT_MIN, FLT_MIN );
+	for ( int iPoint = 0; iPoint < 3; ++iPoint )
+	{
+		for ( int iAxis = 0; iAxis < 3; ++iAxis )
+		{
+			vecMin[iAxis] = min( vecMin[iAxis], pPoints[iPoint][iAxis] );
+			vecMax[iAxis] = max( vecMax[iAxis], pPoints[iPoint][iAxis] );
+		}
+	}
+
+	VectorCopy( vecMin, pPatch->mins );
+	VectorCopy( vecMax, pPatch->maxs );
+
+	if ( !pParentPatch )
+	{
+		VectorCopy( vecMin, pPatch->face_mins );
+		VectorCopy( vecMax, pPatch->face_maxs );
+	}
+	else
+	{
+		VectorCopy( pParentPatch->face_mins, pPatch->face_mins );
+		VectorCopy( pParentPatch->face_maxs, pPatch->face_maxs );
+	}
+
+	// Check for bumpmap.
+	dface_t *pFace = dfaces + pPatch->faceNumber;
+	texinfo_t *pTexInfo = &texinfo[pFace->texinfo];
+	pPatch->needsBumpmap = pTexInfo->flags & SURF_BUMPLIGHT ? true : false;
+
+	// Misc...
+	pPatch->m_IterationKey = 0;
+
+	// Get the base light for the face.
+	if ( !pParentPatch )
+	{
+		BaseLightForFace( &g_pFaces[pPatch->faceNumber], pPatch->baselight, &pPatch->basearea, pPatch->reflectivity );
+	}
+	else
+	{
+		VectorCopy( pParentPatch->baselight, pPatch->baselight );
+		pPatch->basearea = pParentPatch->basearea;
+		pPatch->reflectivity = pParentPatch->reflectivity;
+	}
+
+	return true;
+}
+
+void CVRADDispColl::AddPolysForRayTrace( void )
+{
+	if ( !( m_nContents & MASK_OPAQUE ) )
+		return;
+
+	for ( int ndxTri = 0; ndxTri < m_aTris.Size(); ndxTri++ )
+	{
+		CDispCollTri *tri = m_aTris.Base() + ndxTri;
+		int v[3];
+		for ( int ndxv = 0; ndxv < 3; ndxv++ )
+			v[ndxv] = tri->GetVert(ndxv);
+
+		Vector fullCoverage;
+		fullCoverage.x = 1.0f;
+		g_RtEnv.AddTriangle( TRACE_ID_OPAQUE, m_aVerts[v[0]], m_aVerts[v[1]], m_aVerts[v[2]], fullCoverage );
+	}
+}
\ No newline at end of file