First version of the SOurce SDK 2013

1 files changed, 3262 insertions, 0 deletions

diff --git a/mp/src/public/collisionutils.cpp b/mp/src/public/collisionutils.cpp
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+//========= Copyright Valve Corporation, All rights reserved. ============//

+//

+// Purpose: Common collision utility methods

+//

+// $Header: $

+// $NoKeywords: $

+//=============================================================================//

+

+#if !defined(_STATIC_LINKED) || defined(_SHARED_LIB)

+

+#include "collisionutils.h"

+#include "cmodel.h"

+#include "mathlib/mathlib.h"

+#include "mathlib/vector.h"

+#include "tier0/dbg.h"

+#include <float.h>

+#include "mathlib/vector4d.h"

+#include "trace.h"

+

+// memdbgon must be the last include file in a .cpp file!!!

+#include "tier0/memdbgon.h"

+

+#define UNINIT		-99999.0

+

+//-----------------------------------------------------------------------------

+// Clears the trace

+//-----------------------------------------------------------------------------

+static void Collision_ClearTrace( const Vector &vecRayStart, const Vector &vecRayDelta, CBaseTrace *pTrace )

+{

+	pTrace->startpos = vecRayStart;

+	pTrace->endpos = vecRayStart;

+	pTrace->endpos += vecRayDelta;

+	pTrace->startsolid = false;

+	pTrace->allsolid = false;

+	pTrace->fraction = 1.0f;

+	pTrace->contents = 0;

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute the offset in t along the ray that we'll use for the collision

+//-----------------------------------------------------------------------------

+static float ComputeBoxOffset( const Ray_t& ray )

+{

+	if (ray.m_IsRay)

+		return 1e-3f;

+

+	// Find the projection of the box diagonal along the ray...

+	float offset = FloatMakePositive(ray.m_Extents[0] * ray.m_Delta[0]) +

+					FloatMakePositive(ray.m_Extents[1] * ray.m_Delta[1]) +

+					FloatMakePositive(ray.m_Extents[2] * ray.m_Delta[2]);

+

+	// We need to divide twice: Once to normalize the computation above

+	// so we get something in units of extents, and the second to normalize

+	// that with respect to the entire raycast.

+	offset *= InvRSquared( ray.m_Delta );

+

+	// 1e-3 is an epsilon

+	return offset + 1e-3;

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a swept box against a triangle

+//-----------------------------------------------------------------------------

+float IntersectRayWithTriangle( const Ray_t& ray, 

+		const Vector& v1, const Vector& v2, const Vector& v3, bool oneSided )

+{

+	// This is cute: Use barycentric coordinates to represent the triangle

+	// Vo(1-u-v) + V1u + V2v and intersect that with a line Po + Dt

+	// This gives us 3 equations + 3 unknowns, which we can solve with

+	// Cramer's rule...

+	//		E1x u + E2x v - Dx t = Pox - Vox

+	// There's a couple of other optimizations, Cramer's rule involves

+	// computing the determinant of a matrix which has been constructed

+	// by three vectors. It turns out that 

+	// det | A B C | = -( A x C ) dot B or -(C x B) dot A

+	// which we'll use below..

+

+	Vector edge1, edge2, org;

+	VectorSubtract( v2, v1, edge1 );

+	VectorSubtract( v3, v1, edge2 );

+

+	// Cull out one-sided stuff

+	if (oneSided)

+	{

+		Vector normal;

+		CrossProduct( edge1, edge2, normal );

+		if (DotProduct( normal, ray.m_Delta ) >= 0.0f)

+			return -1.0f;

+	}

+

+	// FIXME: This is inaccurate, but fast for boxes

+	// We want to do a fast separating axis implementation here

+	// with a swept triangle along the reverse direction of the ray.

+

+	// Compute some intermediary terms

+	Vector dirCrossEdge2, orgCrossEdge1;

+	CrossProduct( ray.m_Delta, edge2, dirCrossEdge2 );

+

+	// Compute the denominator of Cramer's rule:

+	//		| -Dx E1x E2x |

+	// det	| -Dy E1y E2y | = (D x E2) dot E1

+	//		| -Dz E1z E2z |

+	float denom = DotProduct( dirCrossEdge2, edge1 );

+	if( FloatMakePositive( denom ) < 1e-6 )

+		return -1.0f;

+	denom = 1.0f / denom;

+

+	// Compute u. It's gotta lie in the range of 0 to 1.

+	//				   | -Dx orgx E2x |

+	// u = denom * det | -Dy orgy E2y | = (D x E2) dot org

+	//				   | -Dz orgz E2z |

+	VectorSubtract( ray.m_Start, v1, org );

+	float u = DotProduct( dirCrossEdge2, org ) * denom;

+	if ((u < 0.0f) || (u > 1.0f))

+		return -1.0f;

+

+	// Compute t and v the same way...

+	// In barycentric coords, u + v < 1

+	CrossProduct( org, edge1, orgCrossEdge1 );

+	float v = DotProduct( orgCrossEdge1, ray.m_Delta ) * denom;

+	if ((v < 0.0f) || (v + u > 1.0f))

+		return -1.0f;

+

+	// Compute the distance along the ray direction that we need to fudge 

+	// when using swept boxes

+	float boxt = ComputeBoxOffset( ray );

+	float t = DotProduct( orgCrossEdge1, edge2 ) * denom;

+	if ((t < -boxt) || (t > 1.0f + boxt))

+		return -1.0f;

+

+	return clamp( t, 0.f, 1.f );

+}

+

+//-----------------------------------------------------------------------------

+// computes the barycentric coordinates of an intersection

+//-----------------------------------------------------------------------------

+

+bool ComputeIntersectionBarycentricCoordinates( const Ray_t& ray, 

+		const Vector& v1, const Vector& v2, const Vector& v3, float& u, float& v,

+		float *t )

+{

+	Vector edge1, edge2, org;

+	VectorSubtract( v2, v1, edge1 );

+	VectorSubtract( v3, v1, edge2 );

+

+	// Compute some intermediary terms

+	Vector dirCrossEdge2, orgCrossEdge1;

+	CrossProduct( ray.m_Delta, edge2, dirCrossEdge2 );

+

+	// Compute the denominator of Cramer's rule:

+	//		| -Dx E1x E2x |

+	// det	| -Dy E1y E2y | = (D x E2) dot E1

+	//		| -Dz E1z E2z |

+	float denom = DotProduct( dirCrossEdge2, edge1 );

+	if( FloatMakePositive( denom ) < 1e-6 )

+		return false;

+	denom = 1.0f / denom;

+

+	// Compute u. It's gotta lie in the range of 0 to 1.

+	//				   | -Dx orgx E2x |

+	// u = denom * det | -Dy orgy E2y | = (D x E2) dot org

+	//				   | -Dz orgz E2z |

+	VectorSubtract( ray.m_Start, v1, org );

+	u = DotProduct( dirCrossEdge2, org ) * denom;

+

+	// Compute t and v the same way...

+	// In barycentric coords, u + v < 1

+	CrossProduct( org, edge1, orgCrossEdge1 );

+	v = DotProduct( orgCrossEdge1, ray.m_Delta ) * denom;

+

+	// Compute the distance along the ray direction that we need to fudge 

+	// when using swept boxes

+	if( t )

+	{

+		float boxt = ComputeBoxOffset( ray );

+		*t = DotProduct( orgCrossEdge1, edge2 ) * denom;

+		if( ( *t < -boxt ) || ( *t > 1.0f + boxt ) )

+			return false;

+	}

+

+	return true;

+}

+

+//-----------------------------------------------------------------------------

+// Intersects a plane with a triangle (requires barycentric definition)

+//-----------------------------------------------------------------------------

+

+int IntersectTriangleWithPlaneBarycentric( const Vector& org, const Vector& edgeU,

+		const Vector& edgeV, const Vector4D& plane, Vector2D* pIntersection )

+{

+	// This uses a barycentric method, since we need that to determine

+	// interpolated points, alphas, and normals

+	// Given the plane equation P dot N + d = 0

+	// and the barycentric coodinate equation P = Org + EdgeU * u + EdgeV * v

+	// Plug em in. Intersection occurs at u = 0 or v = 0 or u + v = 1

+

+	float orgDotNormal = DotProduct( org, plane.AsVector3D() );

+	float edgeUDotNormal = DotProduct( edgeU, plane.AsVector3D() );

+	float edgeVDotNormal = DotProduct( edgeV, plane.AsVector3D() );

+

+	int ptIdx = 0;

+

+	// u = 0

+	if ( edgeVDotNormal != 0.0f )

+	{

+		pIntersection[ptIdx].x = 0.0f;

+		pIntersection[ptIdx].y = - ( orgDotNormal - plane.w ) / edgeVDotNormal;

+		if ((pIntersection[ptIdx].y >= 0.0f) && (pIntersection[ptIdx].y <= 1.0f))

+			++ptIdx;

+	}

+

+	// v = 0

+	if ( edgeUDotNormal != 0.0f )

+	{

+		pIntersection[ptIdx].x = - ( orgDotNormal - plane.w ) / edgeUDotNormal;

+		pIntersection[ptIdx].y = 0.0f;

+		if ((pIntersection[ptIdx].x >= 0.0f) && (pIntersection[ptIdx].x <= 1.0f))

+			++ptIdx;

+	}

+

+	// u + v = 1

+	if (ptIdx == 2)

+		return ptIdx;

+

+	if ( edgeVDotNormal != edgeUDotNormal )

+	{

+		pIntersection[ptIdx].x = - ( orgDotNormal - plane.w + edgeVDotNormal) / 

+			( edgeUDotNormal - edgeVDotNormal);

+		pIntersection[ptIdx].y = 1.0f - pIntersection[ptIdx].x;;

+		if ((pIntersection[ptIdx].x >= 0.0f) && (pIntersection[ptIdx].x <= 1.0f) &&

+			 (pIntersection[ptIdx].y >= 0.0f) && (pIntersection[ptIdx].y <= 1.0f))

+			++ptIdx;

+	}

+

+	Assert( ptIdx < 3 );

+	return ptIdx;

+}

+

+

+//-----------------------------------------------------------------------------

+// Returns true if a box intersects with a sphere

+//-----------------------------------------------------------------------------

+bool IsSphereIntersectingSphere( const Vector& center1, float radius1, 

+								 const Vector& center2, float radius2 )

+{

+	Vector delta;

+	VectorSubtract( center2, center1, delta );

+	float distSq = delta.LengthSqr();

+	float radiusSum = radius1 + radius2;

+	return (distSq <= (radiusSum * radiusSum));

+}

+

+

+//-----------------------------------------------------------------------------

+// Returns true if a box intersects with a sphere

+//-----------------------------------------------------------------------------

+bool IsBoxIntersectingSphere( const Vector& boxMin, const Vector& boxMax, 

+						const Vector& center, float radius )

+{

+	// See Graphics Gems, box-sphere intersection

+	float dmin = 0.0f;

+	float flDelta;

+

+	// Unrolled the loop.. this is a big cycle stealer...

+	if (center[0] < boxMin[0])

+	{

+		flDelta = center[0] - boxMin[0];

+		dmin += flDelta * flDelta;

+	}

+	else if (center[0] > boxMax[0])

+	{

+		flDelta = boxMax[0] - center[0];

+		dmin += flDelta * flDelta;

+	}

+

+	if (center[1] < boxMin[1])

+	{

+		flDelta = center[1] - boxMin[1];

+		dmin += flDelta * flDelta;

+	}

+	else if (center[1] > boxMax[1])

+	{

+		flDelta = boxMax[1] - center[1];

+		dmin += flDelta * flDelta;

+	}

+

+	if (center[2] < boxMin[2])

+	{

+		flDelta = center[2] - boxMin[2];

+		dmin += flDelta * flDelta;

+	}

+	else if (center[2] > boxMax[2])

+	{

+		flDelta = boxMax[2] - center[2];

+		dmin += flDelta * flDelta;

+	}

+

+	return dmin < radius * radius;

+}

+

+bool IsBoxIntersectingSphereExtents( const Vector& boxCenter, const Vector& boxHalfDiag, 

+						const Vector& center, float radius )

+{

+	// See Graphics Gems, box-sphere intersection

+	float dmin = 0.0f;

+	float flDelta, flDiff;

+

+	// Unrolled the loop.. this is a big cycle stealer...

+	flDiff = FloatMakePositive( center.x - boxCenter.x );

+	if (flDiff > boxHalfDiag.x)

+	{

+		flDelta = flDiff - boxHalfDiag.x;

+		dmin += flDelta * flDelta;

+	}

+

+	flDiff = FloatMakePositive( center.y - boxCenter.y );

+	if (flDiff > boxHalfDiag.y)

+	{

+		flDelta = flDiff - boxHalfDiag.y;

+		dmin += flDelta * flDelta;

+	}

+

+	flDiff = FloatMakePositive( center.z - boxCenter.z );

+	if (flDiff > boxHalfDiag.z)

+	{

+		flDelta = flDiff - boxHalfDiag.z;

+		dmin += flDelta * flDelta;

+	}

+

+	return dmin < radius * radius;

+}

+

+

+//-----------------------------------------------------------------------------

+// Returns true if a rectangle intersects with a circle

+//-----------------------------------------------------------------------------

+bool IsCircleIntersectingRectangle( const Vector2D& boxMin, const Vector2D& boxMax, 

+						      const Vector2D& center, float radius )

+{

+	// See Graphics Gems, box-sphere intersection

+	float dmin = 0.0f;

+	float flDelta;

+

+	if (center[0] < boxMin[0])

+	{

+		flDelta = center[0] - boxMin[0];

+		dmin += flDelta * flDelta;

+	}

+	else if (center[0] > boxMax[0])

+	{

+		flDelta = boxMax[0] - center[0];

+		dmin += flDelta * flDelta;

+	}

+

+	if (center[1] < boxMin[1])

+	{

+		flDelta = center[1] - boxMin[1];

+		dmin += flDelta * flDelta;

+	}

+	else if (center[1] > boxMax[1])

+	{

+		flDelta = boxMax[1] - center[1];

+		dmin += flDelta * flDelta;

+	}

+

+	return dmin < radius * radius;

+}

+

+

+//-----------------------------------------------------------------------------

+// returns true if there's an intersection between ray and sphere

+//-----------------------------------------------------------------------------

+bool IsRayIntersectingSphere( const Vector &vecRayOrigin, const Vector &vecRayDelta, 

+		const Vector& vecCenter, float flRadius, float flTolerance )

+{

+	// For this algorithm, find a point on the ray  which is closest to the sphere origin

+	// Do this by making a plane passing through the sphere origin

+	// whose normal is parallel to the ray. Intersect that plane with the ray.

+	// Plane: N dot P = I, N = D (ray direction), I = C dot N = C dot D

+	// Ray: P = O + D * t

+	// D dot ( O + D * t ) = C dot D

+	// D dot O + D dot D * t = C dot D

+	// t = (C - O) dot D / D dot D

+	// Clamp t to (0,1)

+	// Find distance of the point on the ray to the sphere center.

+	Assert( flTolerance >= 0.0f );

+	flRadius += flTolerance;

+

+	Vector vecRayToSphere;

+	VectorSubtract( vecCenter, vecRayOrigin, vecRayToSphere );

+	float flNumerator = DotProduct( vecRayToSphere, vecRayDelta );

+	

+	float t;

+	if (flNumerator <= 0.0f)

+	{

+		t = 0.0f;

+	}

+	else

+	{

+		float flDenominator = DotProduct( vecRayDelta, vecRayDelta );

+		if ( flNumerator > flDenominator )

+			t = 1.0f;

+		else

+			t = flNumerator / flDenominator;

+	}

+	

+	Vector vecClosestPoint;

+	VectorMA( vecRayOrigin, t, vecRayDelta, vecClosestPoint );

+	return ( vecClosestPoint.DistToSqr( vecCenter ) <= flRadius * flRadius );

+

+	// NOTE: This in an alternate algorithm which I didn't use because I'd have to use a sqrt

+	// So it's probably faster to do this other algorithm. I'll leave the comments here

+	// for how to go back if we want to

+

+	// Solve using the ray equation + the sphere equation

+	// P = o + dt

+	// (x - xc)^2 + (y - yc)^2 + (z - zc)^2 = r^2

+	// (ox + dx * t - xc)^2 + (oy + dy * t - yc)^2 + (oz + dz * t - zc)^2 = r^2

+	// (ox - xc)^2 + 2 * (ox-xc) * dx * t + dx^2 * t^2 +

+	//		(oy - yc)^2 + 2 * (oy-yc) * dy * t + dy^2 * t^2 +

+	//		(oz - zc)^2 + 2 * (oz-zc) * dz * t + dz^2 * t^2 = r^2

+	// (dx^2 + dy^2 + dz^2) * t^2 + 2 * ((ox-xc)dx + (oy-yc)dy + (oz-zc)dz) t +

+	//		(ox-xc)^2 + (oy-yc)^2 + (oz-zc)^2 - r^2 = 0

+	// or, t = (-b +/- sqrt( b^2 - 4ac)) / 2a

+	// a = DotProduct( vecRayDelta, vecRayDelta );

+	// b = 2 * DotProduct( vecRayOrigin - vecCenter, vecRayDelta )

+	// c = DotProduct(vecRayOrigin - vecCenter, vecRayOrigin - vecCenter) - flRadius * flRadius;

+	// Valid solutions are possible only if b^2 - 4ac >= 0

+	// Therefore, compute that value + see if we got it	

+}

+

+

+//-----------------------------------------------------------------------------

+//

+// IntersectInfiniteRayWithSphere

+//

+// Returns whether or not there was an intersection. 

+// Returns the two intersection points

+//

+//-----------------------------------------------------------------------------

+bool IntersectInfiniteRayWithSphere( const Vector &vecRayOrigin, const Vector &vecRayDelta, 

+	const Vector &vecSphereCenter, float flRadius, float *pT1, float *pT2 )

+{

+	// Solve using the ray equation + the sphere equation

+	// P = o + dt

+	// (x - xc)^2 + (y - yc)^2 + (z - zc)^2 = r^2

+	// (ox + dx * t - xc)^2 + (oy + dy * t - yc)^2 + (oz + dz * t - zc)^2 = r^2

+	// (ox - xc)^2 + 2 * (ox-xc) * dx * t + dx^2 * t^2 +

+	//		(oy - yc)^2 + 2 * (oy-yc) * dy * t + dy^2 * t^2 +

+	//		(oz - zc)^2 + 2 * (oz-zc) * dz * t + dz^2 * t^2 = r^2

+	// (dx^2 + dy^2 + dz^2) * t^2 + 2 * ((ox-xc)dx + (oy-yc)dy + (oz-zc)dz) t +

+	//		(ox-xc)^2 + (oy-yc)^2 + (oz-zc)^2 - r^2 = 0

+	// or, t = (-b +/- sqrt( b^2 - 4ac)) / 2a

+	// a = DotProduct( vecRayDelta, vecRayDelta );

+	// b = 2 * DotProduct( vecRayOrigin - vecCenter, vecRayDelta )

+	// c = DotProduct(vecRayOrigin - vecCenter, vecRayOrigin - vecCenter) - flRadius * flRadius;

+

+	Vector vecSphereToRay;

+	VectorSubtract(	vecRayOrigin, vecSphereCenter, vecSphereToRay );

+

+	float a = DotProduct( vecRayDelta, vecRayDelta );

+

+	// This would occur in the case of a zero-length ray

+	if ( a == 0.0f )

+	{

+		*pT1 = *pT2 = 0.0f;

+		return vecSphereToRay.LengthSqr() <= flRadius * flRadius;

+	}

+

+	float b = 2 * DotProduct( vecSphereToRay, vecRayDelta );

+	float c = DotProduct( vecSphereToRay, vecSphereToRay ) - flRadius * flRadius;

+	float flDiscrim = b * b - 4 * a * c;

+	if ( flDiscrim < 0.0f )

+		return false;

+

+	flDiscrim = sqrt( flDiscrim );

+	float oo2a = 0.5f / a;

+	*pT1 = ( - b - flDiscrim ) * oo2a;

+	*pT2 = ( - b + flDiscrim ) * oo2a;

+	return true;

+}

+

+

+

+//-----------------------------------------------------------------------------

+//

+// IntersectRayWithSphere

+//

+// Returns whether or not there was an intersection. 

+// Returns the two intersection points, clamped to (0,1)

+//

+//-----------------------------------------------------------------------------

+bool IntersectRayWithSphere( const Vector &vecRayOrigin, const Vector &vecRayDelta, 

+	const Vector &vecSphereCenter, float flRadius, float *pT1, float *pT2 )

+{

+	if ( !IntersectInfiniteRayWithSphere( vecRayOrigin, vecRayDelta, vecSphereCenter, flRadius, pT1, pT2 ) )

+		return false;

+

+	if (( *pT1 > 1.0f ) || ( *pT2 < 0.0f ))

+		return false;

+

+	// Clamp it!

+	if ( *pT1 < 0.0f )

+		*pT1 = 0.0f;

+	if ( *pT2 > 1.0f )

+		*pT2 = 1.0f;

+

+	return true;

+}

+

+

+// returns true if the sphere and cone intersect

+// NOTE: cone sine/cosine are the half angle of the cone

+bool IsSphereIntersectingCone( const Vector &sphereCenter, float sphereRadius, const Vector &coneOrigin, const Vector &coneNormal, float coneSine, float coneCosine )

+{

+	Vector backCenter = coneOrigin - (sphereRadius / coneSine) * coneNormal;

+	Vector delta = sphereCenter - backCenter;

+	float deltaLen = delta.Length();

+	if ( DotProduct(coneNormal, delta) >= deltaLen*coneCosine )

+	{

+		delta = sphereCenter - coneOrigin;

+		deltaLen = delta.Length();

+		if ( -DotProduct(coneNormal, delta) >= deltaLen * coneSine )

+		{

+			return ( deltaLen <= sphereRadius ) ? true : false;

+		}

+		return true;

+	}

+	return false;

+}

+

+

+

+//-----------------------------------------------------------------------------

+// returns true if the point is in the box

+//-----------------------------------------------------------------------------

+bool IsPointInBox( const Vector& pt, const Vector& boxMin, const Vector& boxMax )

+{

+	Assert( boxMin[0] <= boxMax[0] );

+	Assert( boxMin[1] <= boxMax[1] );

+	Assert( boxMin[2] <= boxMax[2] );

+

+	// on x360, force use of SIMD version.

+	if (IsX360())

+	{

+		return IsPointInBox( LoadUnaligned3SIMD(pt.Base()), LoadUnaligned3SIMD(boxMin.Base()), LoadUnaligned3SIMD(boxMax.Base()) ) ;

+	}

+

+	if ( (pt[0] > boxMax[0]) || (pt[0] < boxMin[0]) )

+		return false;

+	if ( (pt[1] > boxMax[1]) || (pt[1] < boxMin[1]) )

+		return false;

+	if ( (pt[2] > boxMax[2]) || (pt[2] < boxMin[2]) )

+		return false;

+	return true;

+}

+

+

+bool IsPointInCone( const Vector &pt, const Vector &origin, const Vector &axis, float cosAngle, float length )

+{

+	Vector delta = pt - origin;

+	float dist = VectorNormalize( delta );

+	float dot = DotProduct( delta, axis );

+	if ( dot < cosAngle )

+		return false;

+	if ( dist * dot > length )

+		return false;

+

+	return true;

+}

+

+

+//-----------------------------------------------------------------------------

+// returns true if there's an intersection between two boxes

+//-----------------------------------------------------------------------------

+bool IsBoxIntersectingBox( const Vector& boxMin1, const Vector& boxMax1, 

+						const Vector& boxMin2, const Vector& boxMax2 )

+{

+	Assert( boxMin1[0] <= boxMax1[0] );

+	Assert( boxMin1[1] <= boxMax1[1] );

+	Assert( boxMin1[2] <= boxMax1[2] );

+	Assert( boxMin2[0] <= boxMax2[0] );

+	Assert( boxMin2[1] <= boxMax2[1] );

+	Assert( boxMin2[2] <= boxMax2[2] );

+

+	if ( (boxMin1[0] > boxMax2[0]) || (boxMax1[0] < boxMin2[0]) )

+		return false;

+	if ( (boxMin1[1] > boxMax2[1]) || (boxMax1[1] < boxMin2[1]) )

+		return false;

+	if ( (boxMin1[2] > boxMax2[2]) || (boxMax1[2] < boxMin2[2]) )

+		return false;

+	return true;

+}

+

+bool IsBoxIntersectingBoxExtents( const Vector& boxCenter1, const Vector& boxHalfDiagonal1, 

+						   const Vector& boxCenter2, const Vector& boxHalfDiagonal2 )

+{

+	Vector vecDelta, vecSize;

+	VectorSubtract( boxCenter1, boxCenter2, vecDelta );

+	VectorAdd( boxHalfDiagonal1, boxHalfDiagonal2, vecSize );

+	return ( FloatMakePositive( vecDelta.x ) <= vecSize.x ) &&

+			( FloatMakePositive( vecDelta.y ) <= vecSize.y ) &&

+			( FloatMakePositive( vecDelta.z ) <= vecSize.z );

+}

+

+

+//-----------------------------------------------------------------------------

+// 

+// IsOBBIntersectingOBB

+//

+// returns true if there's an intersection between two OBBs

+//

+//-----------------------------------------------------------------------------

+bool IsOBBIntersectingOBB( const Vector &vecOrigin1, const QAngle &vecAngles1, const Vector& boxMin1, const Vector& boxMax1, 

+						   const Vector &vecOrigin2, const QAngle &vecAngles2, const Vector& boxMin2, const Vector& boxMax2, float flTolerance )

+{

+	// FIXME: Simple case AABB check doesn't work because the min and max extents are not oriented based on the angle

+	// this fast check would only be good for cubes.

+	/*if ( vecAngles1 == vecAngles2 )

+	{

+		const Vector &vecDelta = vecOrigin2 - vecOrigin1;

+		Vector vecOtherMins, vecOtherMaxs;

+		VectorAdd( boxMin2, vecDelta, vecOtherMins );

+		VectorAdd( boxMax2, vecDelta, vecOtherMaxs );

+		return IsBoxIntersectingBox( boxMin1, boxMax1, vecOtherMins, vecOtherMaxs );

+	}*/

+

+	// OBB test...

+	cplane_t plane;

+	bool bFoundPlane = ComputeSeparatingPlane( vecOrigin1, vecAngles1, boxMin1, boxMax1, 

+		vecOrigin2, vecAngles2, boxMin2, boxMax2, flTolerance, &plane );

+	return (bFoundPlane == false);

+}

+

+// NOTE: This is only very slightly faster on high end PCs and x360

+#define USE_SIMD_RAY_CHECKS 1

+//-----------------------------------------------------------------------------

+// returns true if there's an intersection between box and ray

+//-----------------------------------------------------------------------------

+bool FASTCALL IsBoxIntersectingRay( const Vector& boxMin, const Vector& boxMax, 

+									const Vector& origin, const Vector& vecDelta, float flTolerance )

+{

+	

+#if USE_SIMD_RAY_CHECKS

+	// Load the unaligned ray/box parameters into SIMD registers

+	fltx4 start = LoadUnaligned3SIMD(origin.Base());

+	fltx4 delta = LoadUnaligned3SIMD(vecDelta.Base());

+	fltx4 boxMins = LoadUnaligned3SIMD( boxMin.Base() );

+	fltx4 boxMaxs = LoadUnaligned3SIMD( boxMax.Base() );

+	fltx4 epsilon = ReplicateX4(flTolerance);

+	// compute the mins/maxs of the box expanded by the ray extents

+	// relocate the problem so that the ray start is at the origin.

+	fltx4 offsetMins = SubSIMD(boxMins, start);

+	fltx4 offsetMaxs = SubSIMD(boxMaxs, start);

+	fltx4 offsetMinsExpanded = SubSIMD(offsetMins, epsilon);

+	fltx4 offsetMaxsExpanded = AddSIMD(offsetMaxs, epsilon);

+

+	// Check to see if both the origin (start point) and the end point (delta) are on the front side

+	// of any of the box sides - if so there can be no intersection

+	fltx4 startOutMins = CmpLtSIMD(Four_Zeros, offsetMinsExpanded);

+	fltx4 endOutMins = CmpLtSIMD(delta,offsetMinsExpanded);

+	fltx4 minsMask = AndSIMD( startOutMins, endOutMins );

+	fltx4 startOutMaxs = CmpGtSIMD(Four_Zeros, offsetMaxsExpanded);

+	fltx4 endOutMaxs = CmpGtSIMD(delta,offsetMaxsExpanded);

+	fltx4 maxsMask = AndSIMD( startOutMaxs, endOutMaxs );

+	if ( IsAnyNegative(SetWToZeroSIMD(OrSIMD(minsMask,maxsMask))))

+		return false;

+

+	// now build the per-axis interval of t for intersections

+	fltx4 invDelta = ReciprocalSaturateSIMD(delta);

+	fltx4 tmins = MulSIMD( offsetMinsExpanded, invDelta );

+	fltx4 tmaxs = MulSIMD( offsetMaxsExpanded, invDelta );

+	fltx4 crossPlane = OrSIMD(XorSIMD(startOutMins,endOutMins), XorSIMD(startOutMaxs,endOutMaxs));

+

+	// only consider axes where we crossed a plane

+	tmins = MaskedAssign( crossPlane, tmins, Four_Negative_FLT_MAX );

+	tmaxs = MaskedAssign( crossPlane, tmaxs, Four_FLT_MAX );

+

+	// now sort the interval per axis

+	fltx4 mint = MinSIMD( tmins, tmaxs );

+	fltx4 maxt = MaxSIMD( tmins, tmaxs );

+

+	// now find the intersection of the intervals on all axes

+	fltx4 firstOut = FindLowestSIMD3(maxt);

+	fltx4 lastIn = FindHighestSIMD3(mint);

+	// NOTE: This is really a scalar quantity now [t0,t1] == [lastIn,firstOut]

+	firstOut = MinSIMD(firstOut, Four_Ones);

+	lastIn = MaxSIMD(lastIn, Four_Zeros);

+

+	// If the final interval is valid lastIn<firstOut, check for separation

+	fltx4 separation = CmpGtSIMD(lastIn, firstOut);

+

+	return IsAllZeros(separation);

+#else

+	// On the x360, we force use of the SIMD functions.

+#if defined(_X360) 

+	if (IsX360())

+	{

+		fltx4 delta = LoadUnaligned3SIMD(vecDelta.Base());

+		return IsBoxIntersectingRay( 

+			LoadUnaligned3SIMD(boxMin.Base()), LoadUnaligned3SIMD(boxMax.Base()),

+			LoadUnaligned3SIMD(origin.Base()), delta, ReciprocalSIMD(delta), // ray parameters

+			ReplicateX4(flTolerance) ///< eg from ReplicateX4(flTolerance)

+			);

+	}

+#endif

+	Assert( boxMin[0] <= boxMax[0] );

+	Assert( boxMin[1] <= boxMax[1] );

+	Assert( boxMin[2] <= boxMax[2] );

+

+	// FIXME: Surely there's a faster way

+	float tmin = -FLT_MAX;

+	float tmax = FLT_MAX;

+

+	for (int i = 0; i < 3; ++i)

+	{

+		// Parallel case...

+		if (FloatMakePositive(vecDelta[i]) < 1e-8)

+		{

+			// Check that origin is in the box

+			// if not, then it doesn't intersect..

+			if ( (origin[i] < boxMin[i] - flTolerance) || (origin[i] > boxMax[i] + flTolerance) )

+				return false;

+

+			continue;

+		}

+

+		// non-parallel case

+		// Find the t's corresponding to the entry and exit of

+		// the ray along x, y, and z. The find the furthest entry

+		// point, and the closest exit point. Once that is done,

+		// we know we don't collide if the closest exit point

+		// is behind the starting location. We also don't collide if

+		// the closest exit point is in front of the furthest entry point

+

+		float invDelta = 1.0f / vecDelta[i];

+		float t1 = (boxMin[i] - flTolerance - origin[i]) * invDelta;

+		float t2 = (boxMax[i] + flTolerance - origin[i]) * invDelta;

+		if (t1 > t2)

+		{

+			float temp = t1;

+			t1 = t2;

+			t2 = temp;

+		}

+		if (t1 > tmin)

+			tmin = t1;

+		if (t2 < tmax)

+			tmax = t2;

+		if (tmin > tmax)

+			return false;

+		if (tmax < 0)

+			return false;

+		if (tmin > 1)

+			return false;

+	}

+

+	return true;

+#endif

+}

+

+//-----------------------------------------------------------------------------

+// returns true if there's an intersection between box and ray

+//-----------------------------------------------------------------------------

+bool FASTCALL IsBoxIntersectingRay( const Vector& boxMin, const Vector& boxMax, 

+									const Vector& origin, const Vector& vecDelta,

+									const Vector& vecInvDelta, float flTolerance )

+{	

+#if USE_SIMD_RAY_CHECKS

+	// Load the unaligned ray/box parameters into SIMD registers

+	fltx4 start = LoadUnaligned3SIMD(origin.Base());

+	fltx4 delta = LoadUnaligned3SIMD(vecDelta.Base());

+	fltx4 boxMins = LoadUnaligned3SIMD( boxMin.Base() );

+	fltx4 boxMaxs = LoadUnaligned3SIMD( boxMax.Base() );

+	// compute the mins/maxs of the box expanded by the ray extents

+	// relocate the problem so that the ray start is at the origin.

+	boxMins = SubSIMD(boxMins, start);

+	boxMaxs = SubSIMD(boxMaxs, start);

+

+	// Check to see if both the origin (start point) and the end point (delta) are on the front side

+	// of any of the box sides - if so there can be no intersection

+	fltx4 startOutMins = CmpLtSIMD(Four_Zeros, boxMins);

+	fltx4 endOutMins = CmpLtSIMD(delta,boxMins);

+	fltx4 minsMask = AndSIMD( startOutMins, endOutMins );

+	fltx4 startOutMaxs = CmpGtSIMD(Four_Zeros, boxMaxs);

+	fltx4 endOutMaxs = CmpGtSIMD(delta,boxMaxs);

+	fltx4 maxsMask = AndSIMD( startOutMaxs, endOutMaxs );

+	if ( IsAnyNegative(SetWToZeroSIMD(OrSIMD(minsMask,maxsMask))))

+		return false;

+

+	// now build the per-axis interval of t for intersections

+	fltx4 epsilon = ReplicateX4(flTolerance);

+	fltx4 invDelta = LoadUnaligned3SIMD(vecInvDelta.Base());

+	boxMins = SubSIMD(boxMins, epsilon);

+	boxMaxs = AddSIMD(boxMaxs, epsilon);

+

+	boxMins = MulSIMD( boxMins, invDelta );

+	boxMaxs = MulSIMD( boxMaxs, invDelta );

+

+	fltx4 crossPlane = OrSIMD(XorSIMD(startOutMins,endOutMins), XorSIMD(startOutMaxs,endOutMaxs));

+	// only consider axes where we crossed a plane

+	boxMins = MaskedAssign( crossPlane, boxMins, Four_Negative_FLT_MAX );

+	boxMaxs = MaskedAssign( crossPlane, boxMaxs, Four_FLT_MAX );

+

+	// now sort the interval per axis

+	fltx4 mint = MinSIMD( boxMins, boxMaxs );

+	fltx4 maxt = MaxSIMD( boxMins, boxMaxs );

+

+	// now find the intersection of the intervals on all axes

+	fltx4 firstOut = FindLowestSIMD3(maxt);

+	fltx4 lastIn = FindHighestSIMD3(mint);

+	// NOTE: This is really a scalar quantity now [t0,t1] == [lastIn,firstOut]

+	firstOut = MinSIMD(firstOut, Four_Ones);

+	lastIn = MaxSIMD(lastIn, Four_Zeros);

+

+	// If the final interval is valid lastIn<firstOut, check for separation

+	fltx4 separation = CmpGtSIMD(lastIn, firstOut);

+

+	return IsAllZeros(separation);

+#else

+	// On the x360, we force use of the SIMD functions.

+#if defined(_X360) && !defined(PARANOID_SIMD_ASSERTING)

+	if (IsX360())

+	{

+		return IsBoxIntersectingRay( 

+			LoadUnaligned3SIMD(boxMin.Base()), LoadUnaligned3SIMD(boxMax.Base()),

+			LoadUnaligned3SIMD(origin.Base()), LoadUnaligned3SIMD(vecDelta.Base()), LoadUnaligned3SIMD(vecInvDelta.Base()), // ray parameters

+			ReplicateX4(flTolerance) ///< eg from ReplicateX4(flTolerance)

+			);

+	}

+#endif

+

+	Assert( boxMin[0] <= boxMax[0] );

+	Assert( boxMin[1] <= boxMax[1] );

+	Assert( boxMin[2] <= boxMax[2] );

+

+	// FIXME: Surely there's a faster way

+	float tmin = -FLT_MAX;

+	float tmax = FLT_MAX;

+

+	for ( int i = 0; i < 3; ++i )

+	{

+		// Parallel case...

+		if ( FloatMakePositive( vecDelta[i] ) < 1e-8 )

+		{

+			// Check that origin is in the box, if not, then it doesn't intersect..

+			if ( ( origin[i] < boxMin[i] - flTolerance ) || ( origin[i] > boxMax[i] + flTolerance ) )

+				return false;

+

+			continue;

+		}

+

+		// Non-parallel case

+		// Find the t's corresponding to the entry and exit of

+		// the ray along x, y, and z. The find the furthest entry

+		// point, and the closest exit point. Once that is done,

+		// we know we don't collide if the closest exit point

+		// is behind the starting location. We also don't collide if

+		// the closest exit point is in front of the furthest entry point

+		float t1 = ( boxMin[i] - flTolerance - origin[i] ) * vecInvDelta[i];

+		float t2 = ( boxMax[i] + flTolerance - origin[i] ) * vecInvDelta[i];

+		if ( t1 > t2 )

+		{

+			float temp = t1;

+			t1 = t2;

+			t2 = temp;

+		}

+

+		if (t1 > tmin)

+			tmin = t1;

+

+		if (t2 < tmax)

+			tmax = t2;

+

+		if (tmin > tmax)

+			return false;

+

+		if (tmax < 0)

+			return false;

+

+		if (tmin > 1)

+			return false;

+	}

+

+	return true;

+#endif

+}

+

+//-----------------------------------------------------------------------------

+// Intersects a ray with a aabb, return true if they intersect

+//-----------------------------------------------------------------------------

+bool FASTCALL IsBoxIntersectingRay( const Vector& vecBoxMin, const Vector& vecBoxMax, const Ray_t& ray, float flTolerance )

+{

+	// On the x360, we force use of the SIMD functions.

+#if defined(_X360) 

+	if (IsX360())

+	{

+		return IsBoxIntersectingRay( 

+			LoadUnaligned3SIMD(vecBoxMin.Base()), LoadUnaligned3SIMD(vecBoxMax.Base()),

+			ray, flTolerance);

+	}

+#endif

+

+	if ( !ray.m_IsSwept )

+	{

+		Vector rayMins, rayMaxs;

+		VectorSubtract( ray.m_Start, ray.m_Extents, rayMins );

+		VectorAdd( ray.m_Start, ray.m_Extents, rayMaxs );

+		if ( flTolerance != 0.0f )

+		{

+			rayMins.x -= flTolerance; rayMins.y -= flTolerance; rayMins.z -= flTolerance;

+			rayMaxs.x += flTolerance; rayMaxs.y += flTolerance; rayMaxs.z += flTolerance;

+		}

+		return IsBoxIntersectingBox( vecBoxMin, vecBoxMax, rayMins, rayMaxs );

+	}

+

+	Vector vecExpandedBoxMin, vecExpandedBoxMax;

+	VectorSubtract( vecBoxMin, ray.m_Extents, vecExpandedBoxMin );

+	VectorAdd( vecBoxMax, ray.m_Extents, vecExpandedBoxMax );

+	return IsBoxIntersectingRay( vecExpandedBoxMin, vecExpandedBoxMax, ray.m_Start, ray.m_Delta, flTolerance );

+}

+

+

+//-----------------------------------------------------------------------------

+// returns true if there's an intersection between box and ray (SIMD version)

+//-----------------------------------------------------------------------------

+

+

+#ifdef _X360

+bool FASTCALL IsBoxIntersectingRay( fltx4 boxMin, fltx4 boxMax, 

+								    fltx4 origin, fltx4 delta, fltx4 invDelta, // ray parameters

+									fltx4 vTolerance ///< eg from ReplicateX4(flTolerance)

+									)

+#else

+bool FASTCALL IsBoxIntersectingRay( const fltx4 &inBoxMin, const fltx4 & inBoxMax, 

+								   const fltx4 & origin, const fltx4 & delta, const fltx4 & invDelta, // ray parameters

+								   const fltx4 & vTolerance ///< eg from ReplicateX4(flTolerance)

+								   )

+#endif

+{

+	// Load the unaligned ray/box parameters into SIMD registers

+	// compute the mins/maxs of the box expanded by the ray extents

+	// relocate the problem so that the ray start is at the origin.

+

+#ifdef _X360

+	boxMin = SubSIMD(boxMin, origin);

+	boxMax = SubSIMD(boxMax, origin);

+#else

+	fltx4 boxMin = SubSIMD(inBoxMin, origin);

+	fltx4 boxMax = SubSIMD(inBoxMax, origin);

+#endif

+

+	// Check to see if the origin (start point) and the end point (delta) are on the same side

+	// of any of the box sides - if so there can be no intersection

+	fltx4 startOutMins = AndSIMD( CmpLtSIMD(Four_Zeros, boxMin), CmpLtSIMD(delta,boxMin) );

+	fltx4 startOutMaxs = AndSIMD( CmpGtSIMD(Four_Zeros, boxMax), CmpGtSIMD(delta,boxMax) );

+	if ( IsAnyNegative(SetWToZeroSIMD(OrSIMD(startOutMaxs,startOutMins))))

+		return false;

+

+	// now build the per-axis interval of t for intersections

+	boxMin = SubSIMD(boxMin, vTolerance);

+	boxMax = AddSIMD(boxMax, vTolerance);

+

+	boxMin = MulSIMD( boxMin, invDelta );

+	boxMax = MulSIMD( boxMax, invDelta );

+

+	// now sort the interval per axis

+	fltx4 mint = MinSIMD( boxMin, boxMax );

+	fltx4 maxt = MaxSIMD( boxMin, boxMax );

+

+	// now find the intersection of the intervals on all axes

+	fltx4 firstOut = FindLowestSIMD3(maxt);

+	fltx4 lastIn = FindHighestSIMD3(mint);

+	// NOTE: This is really a scalar quantity now [t0,t1] == [lastIn,firstOut]

+	firstOut = MinSIMD(firstOut, Four_Ones);

+	lastIn = MaxSIMD(lastIn, Four_Zeros);

+

+	// If the final interval is valid lastIn<firstOut, check for separation

+	fltx4 separation = CmpGtSIMD(lastIn, firstOut);

+

+	return IsAllZeros(separation);

+}

+

+

+bool FASTCALL IsBoxIntersectingRay( const fltx4& boxMin, const fltx4& boxMax, 

+								   const Ray_t& ray, float flTolerance )

+{

+	fltx4 vTolerance = ReplicateX4(flTolerance);

+	fltx4 rayStart = LoadAlignedSIMD(ray.m_Start);

+	fltx4 rayExtents = LoadAlignedSIMD(ray.m_Extents);

+	if ( !ray.m_IsSwept )

+	{

+

+		fltx4 rayMins, rayMaxs;

+		rayMins = SubSIMD(rayStart, rayExtents);

+		rayMaxs = AddSIMD(rayStart, rayExtents);

+		rayMins = AddSIMD(rayMins, vTolerance);

+		rayMaxs = AddSIMD(rayMaxs, vTolerance);

+

+		VectorAligned vecBoxMin, vecBoxMax, vecRayMins, vecRayMaxs;

+		StoreAlignedSIMD( vecBoxMin.Base(), boxMin );

+		StoreAlignedSIMD( vecBoxMax.Base(), boxMax );

+		StoreAlignedSIMD( vecRayMins.Base(), rayMins );

+		StoreAlignedSIMD( vecRayMaxs.Base(), rayMaxs );

+

+		return IsBoxIntersectingBox( vecBoxMin, vecBoxMax, vecRayMins, vecRayMaxs );

+	}

+

+	fltx4 rayDelta = LoadAlignedSIMD(ray.m_Delta);

+	fltx4 vecExpandedBoxMin, vecExpandedBoxMax;

+	vecExpandedBoxMin = SubSIMD( boxMin, rayExtents );

+	vecExpandedBoxMax = AddSIMD( boxMax, rayExtents );

+

+	return IsBoxIntersectingRay( vecExpandedBoxMin, vecExpandedBoxMax, rayStart, rayDelta, ReciprocalSIMD(rayDelta), ReplicateX4(flTolerance) );

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray with a ray, return true if they intersect

+// t, s = parameters of closest approach (if not intersecting!)

+//-----------------------------------------------------------------------------

+bool IntersectRayWithRay( const Ray_t &ray0, const Ray_t &ray1, float &t, float &s )

+{

+	Assert( ray0.m_IsRay && ray1.m_IsRay );

+

+	//

+	// r0 = p0 + v0t

+	// r1 = p1 + v1s

+	//

+	// intersection : r0 = r1 :: p0 + v0t = p1 + v1s

+	// NOTE: v(0,1) are unit direction vectors

+	//

+	// subtract p0 from both sides and cross with v1 (NOTE: v1 x v1 = 0)

+	//  (v0 x v1)t = ((p1 - p0 ) x v1)

+	//

+	// dotting  with (v0 x v1) and dividing by |v0 x v1|^2

+	//	t = Det | (p1 - p0) , v1 , (v0 x v1) | / |v0 x v1|^2

+	//  s = Det | (p1 - p0) , v0 , (v0 x v1) | / |v0 x v1|^2

+	//

+	//  Det | A B C | = -( A x C ) dot B or -( C x B ) dot A

+	// 

+	//  NOTE: if |v0 x v1|^2 = 0, then the lines are parallel

+	//

+	Vector v0( ray0.m_Delta );

+	Vector v1( ray1.m_Delta );

+	VectorNormalize( v0 );

+	VectorNormalize( v1 );

+

+	Vector v0xv1 = v0.Cross( v1 );

+	float lengthSq = v0xv1.LengthSqr();

+	if( lengthSq == 0.0f )

+	{

+		t = 0; s = 0;

+		return false;		// parallel

+	}

+

+	Vector p1p0 = ray1.m_Start - ray0.m_Start;

+

+	Vector AxC = p1p0.Cross( v0xv1 );

+	AxC.Negate();

+	float detT = AxC.Dot( v1 );

+	

+	AxC = p1p0.Cross( v0xv1 );

+	AxC.Negate();

+	float detS = AxC.Dot( v0 );

+

+	t = detT / lengthSq;

+	s = detS / lengthSq;

+

+	// intersection????

+	Vector i0, i1;

+	i0 = v0 * t;

+	i1 = v1 * s;

+	i0 += ray0.m_Start;

+	i1 += ray1.m_Start;

+	if( i0.x == i1.x && i0.y == i1.y && i0.z == i1.z )

+		return true;

+

+	return false;

+}

+

+//-----------------------------------------------------------------------------

+// Intersects a ray with a plane, returns distance t along ray.

+//-----------------------------------------------------------------------------

+float IntersectRayWithPlane( const Ray_t& ray, const cplane_t& plane )

+{

+	float denom	= DotProduct( ray.m_Delta, plane.normal );

+	if (denom == 0.0f)

+		return 0.0f;

+

+	denom = 1.0f / denom;

+	return (plane.dist - DotProduct( ray.m_Start, plane.normal )) * denom;

+}

+

+float IntersectRayWithPlane( const Vector& org, const Vector& dir, const cplane_t& plane )

+{

+	float denom	= DotProduct( dir, plane.normal );

+	if (denom == 0.0f)

+		return 0.0f;

+

+	denom = 1.0f / denom;

+	return (plane.dist - DotProduct( org, plane.normal )) * denom;

+}

+

+float IntersectRayWithPlane( const Vector& org, const Vector& dir, const Vector& normal, float dist )

+{

+	float denom	= DotProduct( dir, normal );

+	if (denom == 0.0f)

+		return 0.0f;

+

+	denom = 1.0f / denom;

+	return (dist - DotProduct( org, normal )) * denom;

+}

+

+float IntersectRayWithAAPlane( const Vector& vecStart, const Vector& vecEnd, int nAxis, float flSign, float flDist )

+{

+	float denom	= flSign * (vecEnd[nAxis] - vecStart[nAxis]);

+	if (denom == 0.0f)

+		return 0.0f;

+

+	denom = 1.0f / denom;

+	return (flDist - flSign * vecStart[nAxis]) * denom;

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against a box

+//-----------------------------------------------------------------------------

+bool IntersectRayWithBox( const Vector &vecRayStart, const Vector &vecRayDelta, 

+	const Vector &boxMins, const Vector &boxMaxs, float flTolerance, BoxTraceInfo_t *pTrace )

+{

+	int			i;

+	float		d1, d2;

+	float		f;

+

+	pTrace->t1 = -1.0f;

+	pTrace->t2 = 1.0f;

+	pTrace->hitside = -1;

+

+	// UNDONE: This makes this code a little messy

+	pTrace->startsolid = true;

+

+	for ( i = 0; i < 6; ++i )

+	{

+		if ( i >= 3 )

+		{

+			d1 = vecRayStart[i-3] - boxMaxs[i-3];

+			d2 = d1 + vecRayDelta[i-3];

+		}

+		else

+		{

+			d1 = -vecRayStart[i] + boxMins[i];

+			d2 = d1 - vecRayDelta[i];

+		}

+

+		// if completely in front of face, no intersection

+		if (d1 > 0 && d2 > 0)

+		{

+			// UNDONE: Have to revert this in case it's still set

+			// UNDONE: Refactor to have only 2 return points (true/false) from this function

+			pTrace->startsolid = false;

+			return false;

+		}

+

+		// completely inside, check next face

+		if (d1 <= 0 && d2 <= 0)

+			continue;

+

+		if (d1 > 0)

+		{

+			pTrace->startsolid = false;

+		}

+

+		// crosses face

+		if (d1 > d2)

+		{

+			f = d1 - flTolerance;

+			if ( f < 0 )

+			{

+				f = 0;

+			}

+			f = f / (d1-d2);

+			if (f > pTrace->t1)

+			{

+				pTrace->t1 = f;

+				pTrace->hitside = i;

+			}

+		}

+		else

+		{ 

+			// leave

+			f = (d1 + flTolerance) / (d1-d2);

+			if (f < pTrace->t2)

+			{

+				pTrace->t2 = f;

+			}

+		}

+	}

+

+	return pTrace->startsolid || (pTrace->t1 < pTrace->t2 && pTrace->t1 >= 0.0f);

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against a box

+//-----------------------------------------------------------------------------

+bool IntersectRayWithBox( const Vector &vecRayStart, const Vector &vecRayDelta, 

+	const Vector &boxMins, const Vector &boxMaxs, float flTolerance, CBaseTrace *pTrace, float *pFractionLeftSolid )

+{

+	Collision_ClearTrace( vecRayStart, vecRayDelta, pTrace );

+

+	BoxTraceInfo_t trace;

+

+	if ( IntersectRayWithBox( vecRayStart, vecRayDelta, boxMins, boxMaxs, flTolerance, &trace ) )

+	{

+		pTrace->startsolid = trace.startsolid;

+		if (trace.t1 < trace.t2 && trace.t1 >= 0.0f)

+		{

+			pTrace->fraction = trace.t1;

+			VectorMA( pTrace->startpos, trace.t1, vecRayDelta, pTrace->endpos );

+			pTrace->contents = CONTENTS_SOLID;

+			pTrace->plane.normal = vec3_origin;

+			if ( trace.hitside >= 3 )

+			{

+				trace.hitside -= 3;

+				pTrace->plane.dist = boxMaxs[trace.hitside];

+				pTrace->plane.normal[trace.hitside] = 1.0f;

+				pTrace->plane.type = trace.hitside;

+			}

+			else

+			{

+				pTrace->plane.dist = -boxMins[trace.hitside];

+				pTrace->plane.normal[trace.hitside] = -1.0f;

+				pTrace->plane.type = trace.hitside;

+			}

+			return true;

+		}

+

+		if ( pTrace->startsolid )

+		{

+			pTrace->allsolid = (trace.t2 <= 0.0f) || (trace.t2 >= 1.0f);

+			pTrace->fraction = 0;

+			if ( pFractionLeftSolid )

+			{

+				*pFractionLeftSolid = trace.t2;

+			}

+			pTrace->endpos = pTrace->startpos;

+			pTrace->contents = CONTENTS_SOLID;

+			pTrace->plane.dist = pTrace->startpos[0];

+			pTrace->plane.normal.Init( 1.0f, 0.0f, 0.0f );

+			pTrace->plane.type = 0;

+			pTrace->startpos = vecRayStart + (trace.t2 * vecRayDelta);

+			return true;

+		}

+	}

+

+	return false;

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against a box

+//-----------------------------------------------------------------------------

+bool IntersectRayWithBox( const Ray_t &ray, const Vector &boxMins, const Vector &boxMaxs, 

+						 float flTolerance, CBaseTrace *pTrace, float *pFractionLeftSolid )

+{

+	if ( !ray.m_IsRay )

+	{

+		Vector vecExpandedMins = boxMins - ray.m_Extents;

+		Vector vecExpandedMaxs = boxMaxs + ray.m_Extents;

+		bool bIntersects = IntersectRayWithBox( ray.m_Start, ray.m_Delta, vecExpandedMins, vecExpandedMaxs, flTolerance, pTrace, pFractionLeftSolid );

+		pTrace->startpos += ray.m_StartOffset;

+		pTrace->endpos += ray.m_StartOffset;

+		return bIntersects;

+	}

+	return IntersectRayWithBox( ray.m_Start, ray.m_Delta, boxMins, boxMaxs, flTolerance, pTrace, pFractionLeftSolid );

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against an OBB, returns t1 and t2

+//-----------------------------------------------------------------------------

+bool IntersectRayWithOBB( const Vector &vecRayStart, const Vector &vecRayDelta, 

+	const matrix3x4_t &matOBBToWorld, const Vector &vecOBBMins, const Vector &vecOBBMaxs, 

+	float flTolerance, BoxTraceInfo_t *pTrace )

+{

+	// FIXME: Two transforms is pretty expensive. Should we optimize this?

+	Vector start, delta;

+	VectorITransform( vecRayStart, matOBBToWorld, start );

+	VectorIRotate( vecRayDelta, matOBBToWorld, delta );

+

+	return IntersectRayWithBox( start, delta, vecOBBMins, vecOBBMaxs, flTolerance, pTrace ); 

+}

+

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against an OBB

+//-----------------------------------------------------------------------------

+bool IntersectRayWithOBB( const Vector &vecRayStart, const Vector &vecRayDelta, 

+	const matrix3x4_t &matOBBToWorld, const Vector &vecOBBMins, const Vector &vecOBBMaxs, 

+	float flTolerance, CBaseTrace *pTrace )

+{

+	Collision_ClearTrace( vecRayStart, vecRayDelta, pTrace );

+

+	// FIXME: Make it work with tolerance

+	Assert( flTolerance == 0.0f );

+

+	// OPTIMIZE: Store this in the box instead of computing it here

+	// compute center in local space

+	Vector vecBoxExtents = (vecOBBMins + vecOBBMaxs) * 0.5; 

+	Vector vecBoxCenter;

+

+	// transform to world space

+	VectorTransform( vecBoxExtents, matOBBToWorld, vecBoxCenter );

+

+	// calc extents from local center

+	vecBoxExtents = vecOBBMaxs - vecBoxExtents;

+

+	// OPTIMIZE: This is optimized for world space.  If the transform is fast enough, it may make more

+	// sense to just xform and call UTIL_ClipToBox() instead.  MEASURE THIS.

+

+	// save the extents of the ray along 

+	Vector extent, uextent;

+	Vector segmentCenter = vecRayStart + vecRayDelta - vecBoxCenter;

+

+	extent.Init();

+

+	// check box axes for separation

+	for ( int j = 0; j < 3; j++ )

+	{

+		extent[j] = vecRayDelta.x * matOBBToWorld[0][j] + vecRayDelta.y * matOBBToWorld[1][j] +	vecRayDelta.z * matOBBToWorld[2][j];

+		uextent[j] = fabsf(extent[j]);

+		float coord = segmentCenter.x * matOBBToWorld[0][j] + segmentCenter.y * matOBBToWorld[1][j] +	segmentCenter.z * matOBBToWorld[2][j];

+		coord = fabsf(coord);

+

+		if ( coord > (vecBoxExtents[j] + uextent[j]) )

+			return false;

+	}

+

+	// now check cross axes for separation

+	float tmp, cextent;

+	Vector cross = vecRayDelta.Cross( segmentCenter );

+	cextent = cross.x * matOBBToWorld[0][0] + cross.y * matOBBToWorld[1][0] + cross.z * matOBBToWorld[2][0];

+	cextent = fabsf(cextent);

+	tmp = vecBoxExtents[1]*uextent[2] + vecBoxExtents[2]*uextent[1];

+	if ( cextent > tmp )

+		return false;

+

+	cextent = cross.x * matOBBToWorld[0][1] + cross.y * matOBBToWorld[1][1] + cross.z * matOBBToWorld[2][1];

+	cextent = fabsf(cextent);

+	tmp = vecBoxExtents[0]*uextent[2] + vecBoxExtents[2]*uextent[0];

+	if ( cextent > tmp )

+		return false;

+

+	cextent = cross.x * matOBBToWorld[0][2] + cross.y * matOBBToWorld[1][2] + cross.z * matOBBToWorld[2][2];

+	cextent = fabsf(cextent);

+	tmp = vecBoxExtents[0]*uextent[1] + vecBoxExtents[1]*uextent[0];

+	if ( cextent > tmp )

+		return false;

+

+	// !!! We hit this box !!! compute intersection point and return

+	// Compute ray start in bone space

+	Vector start;

+	VectorITransform( vecRayStart, matOBBToWorld, start );

+

+	// extent is ray.m_Delta in bone space, recompute delta in bone space

+	extent *= 2.0f;

+

+	// delta was prescaled by the current t, so no need to see if this intersection

+	// is closer

+	trace_t boxTrace;

+	if ( !IntersectRayWithBox( start, extent, vecOBBMins, vecOBBMaxs, flTolerance, pTrace ) )

+		return false;

+

+	// Fix up the start/end pos and fraction

+	Vector vecTemp;

+	VectorTransform( pTrace->endpos, matOBBToWorld, vecTemp );

+	pTrace->endpos = vecTemp;

+

+	pTrace->startpos = vecRayStart;

+	pTrace->fraction *= 2.0f;

+

+	// Fix up the plane information

+	float flSign = pTrace->plane.normal[ pTrace->plane.type ];

+	pTrace->plane.normal[0] = flSign * matOBBToWorld[0][pTrace->plane.type];

+	pTrace->plane.normal[1] = flSign * matOBBToWorld[1][pTrace->plane.type];

+	pTrace->plane.normal[2] = flSign * matOBBToWorld[2][pTrace->plane.type];

+	pTrace->plane.dist = DotProduct( pTrace->endpos, pTrace->plane.normal );

+	pTrace->plane.type = 3;

+

+	return true;

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against an OBB

+//-----------------------------------------------------------------------------

+bool IntersectRayWithOBB( const Vector &vecRayOrigin, const Vector &vecRayDelta, 

+	const Vector &vecBoxOrigin, const QAngle &angBoxRotation,

+	const Vector &vecOBBMins, const Vector &vecOBBMaxs, float flTolerance, CBaseTrace *pTrace )

+{

+	if (angBoxRotation == vec3_angle)

+	{

+		Vector vecAbsMins, vecAbsMaxs;

+		VectorAdd( vecBoxOrigin, vecOBBMins, vecAbsMins );

+		VectorAdd( vecBoxOrigin, vecOBBMaxs, vecAbsMaxs );

+		return IntersectRayWithBox( vecRayOrigin, vecRayDelta, vecAbsMins, vecAbsMaxs, flTolerance, pTrace ); 

+	}

+

+	matrix3x4_t obbToWorld;

+	AngleMatrix( angBoxRotation, vecBoxOrigin, obbToWorld );

+	return IntersectRayWithOBB( vecRayOrigin, vecRayDelta, obbToWorld, vecOBBMins, vecOBBMaxs, flTolerance, pTrace );

+}

+

+

+//-----------------------------------------------------------------------------

+// Box support map

+//-----------------------------------------------------------------------------

+inline void ComputeSupportMap( const Vector &vecDirection, const Vector &vecBoxMins, 

+				const Vector &vecBoxMaxs, float pDist[2] )

+{

+	int nIndex = (vecDirection.x > 0.0f);

+	pDist[nIndex] = vecBoxMaxs.x * vecDirection.x;

+	pDist[1 - nIndex] = vecBoxMins.x * vecDirection.x;

+

+	nIndex = (vecDirection.y > 0.0f);

+	pDist[nIndex] += vecBoxMaxs.y * vecDirection.y;

+	pDist[1 - nIndex] += vecBoxMins.y * vecDirection.y;

+

+	nIndex = (vecDirection.z > 0.0f);

+	pDist[nIndex] += vecBoxMaxs.z * vecDirection.z;

+	pDist[1 - nIndex] += vecBoxMins.z * vecDirection.z;

+}

+

+inline void ComputeSupportMap( const Vector &vecDirection, int i1, int i2, 

+	const Vector &vecBoxMins, const Vector &vecBoxMaxs, float pDist[2] )

+{

+	int nIndex = (vecDirection[i1] > 0.0f);

+	pDist[nIndex] = vecBoxMaxs[i1] * vecDirection[i1];

+	pDist[1 - nIndex] = vecBoxMins[i1] * vecDirection[i1];

+

+	nIndex = (vecDirection[i2] > 0.0f);

+	pDist[nIndex] += vecBoxMaxs[i2] * vecDirection[i2];

+	pDist[1 - nIndex] += vecBoxMins[i2] * vecDirection[i2];

+}

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against an OBB

+//-----------------------------------------------------------------------------

+static int s_ExtIndices[3][2] = 

+{

+	{ 2, 1 },

+	{ 0, 2 },

+	{ 0, 1 },

+};

+

+static int s_MatIndices[3][2] = 

+{

+	{ 1, 2 },

+	{ 2, 0 },

+	{ 1, 0 },

+};

+

+bool IntersectRayWithOBB( const Ray_t &ray, const matrix3x4_t &matOBBToWorld,

+	const Vector &vecOBBMins, const Vector &vecOBBMaxs, float flTolerance, CBaseTrace *pTrace )

+{

+	if ( ray.m_IsRay )

+	{

+		return IntersectRayWithOBB( ray.m_Start, ray.m_Delta, matOBBToWorld, 

+			vecOBBMins, vecOBBMaxs, flTolerance, pTrace );

+	}

+

+	Collision_ClearTrace( ray.m_Start + ray.m_StartOffset, ray.m_Delta, pTrace );

+

+	// Compute a bounding sphere around the bloated OBB

+	Vector vecOBBCenter;

+	VectorAdd( vecOBBMins, vecOBBMaxs, vecOBBCenter );

+	vecOBBCenter *= 0.5f;

+	vecOBBCenter.x += matOBBToWorld[0][3];

+	vecOBBCenter.y += matOBBToWorld[1][3];

+	vecOBBCenter.z += matOBBToWorld[2][3];

+

+	Vector vecOBBHalfDiagonal;

+	VectorSubtract( vecOBBMaxs, vecOBBMins, vecOBBHalfDiagonal );

+	vecOBBHalfDiagonal *= 0.5f;

+

+	float flRadius = vecOBBHalfDiagonal.Length() + ray.m_Extents.Length();

+	if ( !IsRayIntersectingSphere( ray.m_Start, ray.m_Delta, vecOBBCenter, flRadius, flTolerance ) )

+		return false;

+

+	// Ok, we passed the trivial reject, so lets do the dirty deed.

+	// Basically we're going to do the GJK thing explicitly. We'll shrink the ray down

+	// to a point, and bloat the OBB by the ray's extents. This will generate facet

+	// planes which are perpendicular to all of the separating axes typically seen in

+	// a standard seperating axis implementation.

+

+	// We're going to create a number of planes through various vertices in the OBB

+	// which represent all of the separating planes. Then we're going to bloat the planes

+	// by the ray extents.

+	

+	// We're going to do all work in OBB-space because it's easier to do the

+	// support-map in this case

+

+	// First, transform the ray into the space of the OBB

+	Vector vecLocalRayOrigin, vecLocalRayDirection;

+	VectorITransform( ray.m_Start, matOBBToWorld, vecLocalRayOrigin );

+	VectorIRotate( ray.m_Delta, matOBBToWorld, vecLocalRayDirection );

+

+	// Next compute all separating planes

+	Vector pPlaneNormal[15];

+	float ppPlaneDist[15][2];

+

+	int i;

+	for ( i = 0; i < 3; ++i )

+	{

+		// Each plane needs to be bloated an amount = to the abs dot product of 

+		// the ray extents with the plane normal

+		// For the OBB planes, do it in world space; 

+		// and use the direction of the OBB (the ith column of matOBBToWorld) in world space vs extents

+		pPlaneNormal[i].Init( );

+		pPlaneNormal[i][i] = 1.0f;

+

+		float flExtentDotNormal = 

+			FloatMakePositive( matOBBToWorld[0][i] * ray.m_Extents.x ) +

+			FloatMakePositive( matOBBToWorld[1][i] * ray.m_Extents.y ) +

+			FloatMakePositive( matOBBToWorld[2][i] * ray.m_Extents.z );

+

+		ppPlaneDist[i][0] = vecOBBMins[i] - flExtentDotNormal; 

+		ppPlaneDist[i][1] = vecOBBMaxs[i] + flExtentDotNormal;

+

+		// For the ray-extents planes, they are bloated by the extents

+		// Use the support map to determine which

+		VectorCopy( matOBBToWorld[i], pPlaneNormal[i+3].Base() ); 

+		ComputeSupportMap( pPlaneNormal[i+3], vecOBBMins, vecOBBMaxs, ppPlaneDist[i+3] );

+		ppPlaneDist[i+3][0] -= ray.m_Extents[i];

+		ppPlaneDist[i+3][1] += ray.m_Extents[i];

+

+		// Now the edge cases... (take the cross product of x,y,z axis w/ ray extent axes

+		// given by the rows of the obb to world matrix. 

+		// Compute the ray extent bloat in world space because it's easier...

+

+		// These are necessary to compute the world-space versions of

+		// the edges so we can compute the extent dot products

+		float flRayExtent0 = ray.m_Extents[s_ExtIndices[i][0]];

+		float flRayExtent1 = ray.m_Extents[s_ExtIndices[i][1]];

+		const float *pMatRow0 = matOBBToWorld[s_MatIndices[i][0]];

+		const float *pMatRow1 = matOBBToWorld[s_MatIndices[i][1]];

+

+		// x axis of the OBB + world ith axis

+		pPlaneNormal[i+6].Init( 0.0f, -matOBBToWorld[i][2], matOBBToWorld[i][1] );

+		ComputeSupportMap( pPlaneNormal[i+6], 1, 2, vecOBBMins, vecOBBMaxs, ppPlaneDist[i+6] );

+		flExtentDotNormal = 

+			FloatMakePositive( pMatRow0[0] ) * flRayExtent0 +

+			FloatMakePositive( pMatRow1[0] ) * flRayExtent1;

+		ppPlaneDist[i+6][0] -= flExtentDotNormal;

+		ppPlaneDist[i+6][1] += flExtentDotNormal;

+		

+		// y axis of the OBB + world ith axis

+		pPlaneNormal[i+9].Init( matOBBToWorld[i][2], 0.0f, -matOBBToWorld[i][0] );

+		ComputeSupportMap( pPlaneNormal[i+9], 0, 2, vecOBBMins, vecOBBMaxs, ppPlaneDist[i+9] );

+		flExtentDotNormal = 

+			FloatMakePositive( pMatRow0[1] ) * flRayExtent0 +

+			FloatMakePositive( pMatRow1[1] ) * flRayExtent1;

+		ppPlaneDist[i+9][0] -= flExtentDotNormal;

+		ppPlaneDist[i+9][1] += flExtentDotNormal;

+

+		// z axis of the OBB + world ith axis

+		pPlaneNormal[i+12].Init( -matOBBToWorld[i][1], matOBBToWorld[i][0], 0.0f );

+		ComputeSupportMap( pPlaneNormal[i+12], 0, 1, vecOBBMins, vecOBBMaxs, ppPlaneDist[i+12] );

+		flExtentDotNormal = 

+			FloatMakePositive( pMatRow0[2] ) * flRayExtent0 +

+			FloatMakePositive( pMatRow1[2] ) * flRayExtent1;

+		ppPlaneDist[i+12][0] -= flExtentDotNormal;

+		ppPlaneDist[i+12][1] += flExtentDotNormal;

+	}

+

+	float enterfrac, leavefrac;

+	float d1[2], d2[2];

+	float f;

+

+	int hitplane = -1;

+	int hitside = -1;

+	enterfrac = -1.0f;

+	leavefrac = 1.0f;

+

+	pTrace->startsolid = true;

+

+	Vector vecLocalRayEnd;

+	VectorAdd( vecLocalRayOrigin, vecLocalRayDirection, vecLocalRayEnd );

+

+	for ( i = 0; i < 15; ++i )

+	{

+		// FIXME: Not particularly optimal since there's a lot of 0's in the plane normals

+		float flStartDot = DotProduct( pPlaneNormal[i], vecLocalRayOrigin );

+		float flEndDot = DotProduct( pPlaneNormal[i], vecLocalRayEnd );

+

+		// NOTE: Negative here is because the plane normal + dist 

+		// are defined in negative terms for the far plane (plane dist index 0)

+		d1[0] = -(flStartDot - ppPlaneDist[i][0]);

+		d2[0] = -(flEndDot - ppPlaneDist[i][0]);

+

+		d1[1] = flStartDot - ppPlaneDist[i][1];

+		d2[1] = flEndDot - ppPlaneDist[i][1];

+

+		int j;

+		for ( j = 0; j < 2; ++j )

+		{

+			// if completely in front near plane or behind far plane no intersection

+			if (d1[j] > 0 && d2[j] > 0)

+				return false;

+

+			// completely inside, check next plane set

+			if (d1[j] <= 0 && d2[j] <= 0)

+				continue;

+

+			if (d1[j] > 0)

+			{

+				pTrace->startsolid = false;

+			}

+

+			// crosses face

+			float flDenom = 1.0f / (d1[j] - d2[j]);

+			if (d1[j] > d2[j])

+			{

+				f = d1[j] - flTolerance;

+				if ( f < 0 )

+				{

+					f = 0;

+				}

+				f *= flDenom;

+				if (f > enterfrac)

+				{

+					enterfrac = f;

+					hitplane = i;

+					hitside = j;

+				}

+			}

+			else

+			{ 

+				// leave

+				f = (d1[j] + flTolerance) * flDenom;

+				if (f < leavefrac)

+				{

+					leavefrac = f;

+				}

+			}

+		}

+	}

+

+	if (enterfrac < leavefrac && enterfrac >= 0.0f)

+	{

+		pTrace->fraction = enterfrac;

+		VectorMA( pTrace->startpos, enterfrac, ray.m_Delta, pTrace->endpos );

+		pTrace->contents = CONTENTS_SOLID;

+

+		// Need to transform the plane into world space...

+		cplane_t temp;

+		temp.normal = pPlaneNormal[hitplane];

+		temp.dist = ppPlaneDist[hitplane][hitside];

+		if (hitside == 0)

+		{

+			temp.normal *= -1.0f;

+			temp.dist *= -1.0f;

+		}

+		temp.type = 3;

+

+		MatrixITransformPlane( matOBBToWorld, temp, pTrace->plane );

+		return true;

+	}

+

+	if ( pTrace->startsolid )

+	{

+		pTrace->allsolid = (leavefrac <= 0.0f) || (leavefrac >= 1.0f);

+		pTrace->fraction = 0;

+		pTrace->endpos = pTrace->startpos;

+		pTrace->contents = CONTENTS_SOLID;

+		pTrace->plane.dist = pTrace->startpos[0];

+		pTrace->plane.normal.Init( 1.0f, 0.0f, 0.0f );

+		pTrace->plane.type = 0;

+		return true;

+	}

+

+	return false;

+}

+

+

+//-----------------------------------------------------------------------------

+// Intersects a ray against an OBB

+//-----------------------------------------------------------------------------

+bool IntersectRayWithOBB( const Ray_t &ray, const Vector &vecBoxOrigin, const QAngle &angBoxRotation,

+	const Vector &vecOBBMins, const Vector &vecOBBMaxs, float flTolerance, CBaseTrace *pTrace )

+{

+	if ( angBoxRotation == vec3_angle )

+	{

+		Vector vecWorldMins, vecWorldMaxs;

+		VectorAdd( vecBoxOrigin, vecOBBMins, vecWorldMins );

+		VectorAdd( vecBoxOrigin, vecOBBMaxs, vecWorldMaxs );

+		return IntersectRayWithBox( ray, vecWorldMins, vecWorldMaxs, flTolerance, pTrace );

+	}

+

+	if ( ray.m_IsRay )

+	{

+		return IntersectRayWithOBB( ray.m_Start, ray.m_Delta, vecBoxOrigin, angBoxRotation, vecOBBMins, vecOBBMaxs, flTolerance, pTrace );

+	}

+

+	matrix3x4_t matOBBToWorld;

+	AngleMatrix( angBoxRotation, vecBoxOrigin, matOBBToWorld );

+	return IntersectRayWithOBB( ray, matOBBToWorld, vecOBBMins, vecOBBMaxs, flTolerance, pTrace );

+}

+

+	

+//-----------------------------------------------------------------------------

+//

+//-----------------------------------------------------------------------------

+void GetNonMajorAxes( const Vector &vNormal, Vector2D &axes )

+{

+	axes[0] = 0;

+	axes[1] = 1;

+

+	if( FloatMakePositive( vNormal.x ) > FloatMakePositive( vNormal.y ) )

+	{

+		if( FloatMakePositive( vNormal.x ) > FloatMakePositive( vNormal.z ) )

+		{

+			axes[0] = 1;

+			axes[1] = 2;

+		}

+	}

+	else

+	{

+		if( FloatMakePositive( vNormal.y ) > FloatMakePositive( vNormal.z ) )

+		{

+			axes[0] = 0;

+			axes[1] = 2;

+		}

+	}

+}

+

+

+//-----------------------------------------------------------------------------

+//-----------------------------------------------------------------------------

+QuadBarycentricRetval_t QuadWithParallelEdges( const Vector &vecOrigin, 

+	const Vector &vecU, float lengthU, const Vector &vecV, float lengthV,

+	const Vector &pt, Vector2D &vecUV )

+{

+	Ray_t rayAxis;

+	Ray_t rayPt;

+

+	//

+	// handle the u axis

+	//

+	rayAxis.m_Start = vecOrigin;

+	rayAxis.m_Delta = vecU;

+	rayAxis.m_IsRay = true;

+

+	rayPt.m_Start = pt;

+	rayPt.m_Delta = vecV * -( lengthV * 10.0f );

+	rayPt.m_IsRay = true;

+

+	float s, t;

+	IntersectRayWithRay( rayAxis, rayPt, t, s );

+	vecUV[0] = t / lengthU;

+

+	//

+	// handle the v axis

+	//

+	rayAxis.m_Delta = vecV;

+

+	rayPt.m_Delta = vecU * -( lengthU * 10.0f );

+

+	IntersectRayWithRay( rayAxis, rayPt, t, s );

+	vecUV[1] = t / lengthV;

+

+	// inside of the quad??

+	if( ( vecUV[0] < 0.0f ) || ( vecUV[0] > 1.0f ) || 

+		( vecUV[1] < 0.0f ) || ( vecUV[1] > 1.0f ) )

+		return BARY_QUADRATIC_FALSE;

+

+	return BARY_QUADRATIC_TRUE;

+}

+

+

+//-----------------------------------------------------------------------------

+//-----------------------------------------------------------------------------

+void ResolveQuadratic( double tPlus, double tMinus, 

+					   const Vector axisU0, const Vector axisU1,

+					   const Vector axisV0, const Vector axisV1,

+					   const Vector axisOrigin, const Vector pt,

+					   int projU, double &s, double &t )

+{

+	// calculate the sPlus, sMinus pair(s)

+	double sDenomPlus = ( axisU0[projU] * ( 1 - tPlus ) ) + ( axisU1[projU] * tPlus );

+	double sDenomMinus = ( axisU0[projU] * ( 1 - tMinus ) ) + ( axisU1[projU] * tMinus );

+

+	double sPlus = UNINIT, sMinus = UNINIT;

+	if( FloatMakePositive( sDenomPlus ) >= 1e-5 )

+	{

+		sPlus = ( pt[projU] - axisOrigin[projU] - ( axisV0[projU] * tPlus ) ) / sDenomPlus; 

+	}

+

+	if( FloatMakePositive( sDenomMinus ) >= 1e-5 )

+	{

+		sMinus = ( pt[projU] - axisOrigin[projU] - ( axisV0[projU] * tMinus ) ) / sDenomMinus; 

+	}

+	

+	if( ( tPlus >= 0.0 ) && ( tPlus <= 1.0 ) && ( sPlus >= 0.0 ) && ( sPlus <= 1.0 ) )

+	{

+		s = sPlus;

+		t = tPlus;

+		return;

+	}

+

+	if( ( tMinus >= 0.0 ) && ( tMinus <= 1.0 ) && ( sMinus >= 0.0 ) && ( sMinus <= 1.0 ) )

+	{

+		s = sMinus;

+		t = tMinus;

+		return;

+	}

+

+	double s0, t0, s1, t1;

+

+	s0 = sPlus;

+	t0 = tPlus;

+	if( s0 >= 1.0 ) { s0 -= 1.0; }

+	if( t0 >= 1.0 ) { t0 -= 1.0; }

+

+	s1 = sMinus;

+	t1 = tMinus;

+	if( s1 >= 1.0 ) { s1 -= 1.0; }

+	if( t1 >= 1.0 ) { t1 -= 1.0; }

+

+	s0 = FloatMakePositive( s0 );

+	t0 = FloatMakePositive( t0 );

+	s1 = FloatMakePositive( s1 );

+	t1 = FloatMakePositive( t1 );

+

+	double max0, max1;

+	max0 = s0;

+	if( t0 > max0 ) { max0 = t0; }

+	max1 = s1;

+	if( t1 > max1 ) { max1 = t1; }

+

+	if( max0 > max1 )

+	{

+		s = sMinus;

+		t = tMinus;

+	}

+	else

+	{

+		s = sPlus;

+		t = tPlus;

+	}

+}

+

+

+//-----------------------------------------------------------------------------

+//

+//-----------------------------------------------------------------------------

+

+QuadBarycentricRetval_t PointInQuadToBarycentric( const Vector &v1, const Vector &v2, 

+	const Vector &v3, const Vector &v4, const Vector &point, Vector2D &uv )

+{

+#define PIQ_TEXTURE_EPSILON		0.001

+#define PIQ_PLANE_EPSILON		0.1

+#define PIQ_DOT_EPSILON			0.99f

+

+	//

+	// Think of a quad with points v1, v2, v3, v4 and u, v line segments

+	// u0 = v2 - v1

+	// u1 = v3 - v4

+	// v0 = v4 - v1

+	// v1 = v3 - v2

+	//

+	Vector axisU[2], axisV[2];

+	Vector axisUNorm[2], axisVNorm[2];

+	axisU[0] = axisUNorm[0] = v2 - v1;

+	axisU[1] = axisUNorm[1] = v3 - v4;

+	axisV[0] = axisVNorm[0] = v4 - v1;

+	axisV[1] = axisVNorm[1] = v3 - v2;

+

+	float lengthU[2], lengthV[2];

+	lengthU[0] = VectorNormalize( axisUNorm[0] );

+	lengthU[1] = VectorNormalize( axisUNorm[1] );

+	lengthV[0] = VectorNormalize( axisVNorm[0] );

+	lengthV[1] = VectorNormalize( axisVNorm[1] );

+

+	//

+	// check for an early out - parallel opposite edges!

+	// NOTE: quad property if 1 set of opposite edges is parallel and equal

+	//       in length, then the other set of edges is as well

+	//

+	if( axisUNorm[0].Dot( axisUNorm[1] ) > PIQ_DOT_EPSILON )

+	{

+		if( FloatMakePositive( lengthU[0] - lengthU[1] ) < PIQ_PLANE_EPSILON )

+		{

+			return QuadWithParallelEdges( v1, axisUNorm[0], lengthU[0], axisVNorm[0], lengthV[0], point, uv );

+		}

+	}

+

+	//

+	// since we are solving for s in our equations below we need to ensure that

+	// the v axes are non-parallel

+	//

+	bool bFlipped = false;

+	if( axisVNorm[0].Dot( axisVNorm[1] ) > PIQ_DOT_EPSILON )

+	{

+		Vector tmp[2];

+		tmp[0] = axisV[0];

+		tmp[1] = axisV[1];

+		axisV[0] = axisU[0];

+		axisV[1] = axisU[1];

+		axisU[0] = tmp[0];

+		axisU[1] = tmp[1];

+		bFlipped = true;

+	}

+

+	//

+	// get the "projection" axes

+	//

+	Vector2D projAxes;

+	Vector vNormal = axisU[0].Cross( axisV[0] );

+	GetNonMajorAxes( vNormal, projAxes );

+

+	//

+	// NOTE: axisU[0][projAxes[0]] < axisU[0][projAxes[1]], 

+	//       this is done to decrease error when dividing later

+	//

+	if( FloatMakePositive( axisU[0][projAxes[0]] ) < FloatMakePositive( axisU[0][projAxes[1]] ) )

+	{

+		int tmp = projAxes[0];

+		projAxes[0] = projAxes[1];

+		projAxes[1] = tmp;

+	}

+

+	// Here's how we got these equations:

+	//

+	// Given the points and u,v line segments above...

+	//

+	// Then:

+	//

+	// (1.0) PT = P0 + U0 * s + V * t

+	//

+	// where

+	//

+	// (1.1) V = V0 + s * (V1 - V0)

+	// (1.2) U = U0 + t * (U1 - U0)

+	// 

+	// Therefore (from 1.1 + 1.0):

+	// PT - P0 = U0 * s + (V0 + s * (V1-V0)) * t

+	// Group s's:

+	// PT - P0 - t * V0 = s * (U0 + t * (V1-V0))

+	// Two equations and two unknowns in x and y get you the following quadratic:

+	//

+	// solve the quadratic

+	//

+	double s = 0.0, t = 0.0;

+	double A, negB, C;

+

+	A = ( axisU[0][projAxes[1]] * axisV[0][projAxes[0]] ) - 

+		( axisU[0][projAxes[0]] * axisV[0][projAxes[1]] ) - 

+		( axisU[1][projAxes[1]] * axisV[0][projAxes[0]] ) + 

+		( axisU[1][projAxes[0]] * axisV[0][projAxes[1]] );

+	C = ( v1[projAxes[1]] * axisU[0][projAxes[0]] ) - 

+		( point[projAxes[1]] * axisU[0][projAxes[0]] ) - 

+		( v1[projAxes[0]] * axisU[0][projAxes[1]] ) + 

+		( point[projAxes[0]] * axisU[0][projAxes[1]] );

+	negB = C - 

+		  ( v1[projAxes[1]] * axisU[1][projAxes[0]] ) + 

+		  ( point[projAxes[1]] * axisU[1][projAxes[0]] ) + 

+		  ( v1[projAxes[0]] * axisU[1][projAxes[1]] ) - 

+		  ( point[projAxes[0]] * axisU[1][projAxes[1]] ) + 

+		  ( axisU[0][projAxes[1]] * axisV[0][projAxes[0]] ) - 

+		  ( axisU[0][projAxes[0]] * axisV[0][projAxes[1]] );

+

+	if( ( A > -PIQ_PLANE_EPSILON ) && ( A < PIQ_PLANE_EPSILON ) )

+	{

+		// shouldn't be here -- this should have been take care of in the "early out"

+//		Assert( 0 );

+

+		Vector vecUAvg, vecVAvg;

+		vecUAvg = ( axisUNorm[0] + axisUNorm[1] ) * 0.5f;

+		vecVAvg = ( axisVNorm[0] + axisVNorm[1] ) * 0.5f;

+		

+		float fLengthUAvg = ( lengthU[0] + lengthU[1] ) * 0.5f;

+		float fLengthVAvg = ( lengthV[0] + lengthV[1] ) * 0.5f;

+

+		return QuadWithParallelEdges( v1, vecUAvg, fLengthUAvg, vecVAvg, fLengthVAvg, point, uv );

+

+#if 0

+		// legacy code -- kept here for completeness!

+

+		// not a quadratic -- solve linearly

+		t = C / negB;

+

+		// See (1.2) above

+		float ui = axisU[0][projAxes[0]] + t * ( axisU[1][projAxes[0]] - axisU[0][projAxes[0]] );

+		if( FloatMakePositive( ui ) >= 1e-5 )

+		{

+			// See (1.0) above

+			s = ( point[projAxes[0]] - v1[projAxes[0]] - axisV[0][projAxes[0]] * t ) / ui;

+		}

+#endif

+	}

+	else

+	{

+		// (-b +/- sqrt( b^2 - 4ac )) / 2a

+		double discriminant = (negB*negB) - (4.0f * A * C);

+		if( discriminant < 0.0f )

+		{

+			uv[0] = -99999.0f;

+			uv[1] = -99999.0f;

+			return BARY_QUADRATIC_NEGATIVE_DISCRIMINANT;

+		}

+

+		double quad = sqrt( discriminant );

+		double QPlus = ( negB + quad ) / ( 2.0f * A );

+		double QMinus = ( negB - quad ) / ( 2.0f * A );

+

+		ResolveQuadratic( QPlus, QMinus, axisU[0], axisU[1], axisV[0], axisV[1], v1, point, projAxes[0], s, t );

+	}

+

+	if( !bFlipped )

+	{

+		uv[0] = ( float )s;

+		uv[1] = ( float )t;

+	}

+	else

+	{

+		uv[0] = ( float )t;

+		uv[1] = ( float )s;

+	}

+

+	// inside of the quad??

+	if( ( uv[0] < 0.0f ) || ( uv[0] > 1.0f ) || ( uv[1] < 0.0f ) || ( uv[1] > 1.0f ) )

+		return BARY_QUADRATIC_FALSE;

+	

+	return BARY_QUADRATIC_TRUE;

+

+#undef PIQ_TEXTURE_EPSILON

+#undef PIQ_PLANE_EPSILON

+}

+

+

+//-----------------------------------------------------------------------------

+//-----------------------------------------------------------------------------

+void PointInQuadFromBarycentric( const Vector &v1, const Vector &v2, const Vector &v3, const Vector &v4,

+								 const Vector2D &uv, Vector &point )

+{

+	//

+	// Think of a quad with points v1, v2, v3, v4 and u, v line segments

+	// find the ray from v0 edge to v1 edge at v

+	//

+	Vector vPts[2];

+	VectorLerp( v1, v4, uv[1], vPts[0] );

+	VectorLerp( v2, v3, uv[1], vPts[1] );

+	VectorLerp( vPts[0], vPts[1], uv[0], point ); 

+}

+

+

+//-----------------------------------------------------------------------------

+//-----------------------------------------------------------------------------

+void TexCoordInQuadFromBarycentric( const Vector2D &v1, const Vector2D &v2, const Vector2D &v3, const Vector2D &v4,

+								    const Vector2D &uv, Vector2D &texCoord )

+{

+	//

+	// Think of a quad with points v1, v2, v3, v4 and u, v line segments

+	// find the ray from v0 edge to v1 edge at v

+	//

+	Vector2D vCoords[2];

+	Vector2DLerp( v1, v4, uv[1], vCoords[0] );

+	Vector2DLerp( v2, v3, uv[1], vCoords[1] );

+	Vector2DLerp( vCoords[0], vCoords[1], uv[0], texCoord ); 

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute point from barycentric specification

+// Edge u goes from v0 to v1, edge v goes from v0 to v2

+//-----------------------------------------------------------------------------

+void ComputePointFromBarycentric( const Vector& v0, const Vector& v1, const Vector& v2, 

+								 float u, float v, Vector& pt )

+{

+	Vector edgeU, edgeV;

+	VectorSubtract( v1, v0, edgeU );

+	VectorSubtract( v2, v0, edgeV );

+	VectorMA( v0, u, edgeU, pt );

+	VectorMA( pt, v, edgeV, pt );

+}

+

+void ComputePointFromBarycentric( const Vector2D& v0, const Vector2D& v1, const Vector2D& v2, 

+								 float u, float v, Vector2D& pt )

+{

+	Vector2D edgeU, edgeV;

+	Vector2DSubtract( v1, v0, edgeU );

+	Vector2DSubtract( v2, v0, edgeV );

+	Vector2DMA( v0, u, edgeU, pt );

+	Vector2DMA( pt, v, edgeV, pt );

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute a matrix that has the correct orientation but which has an origin at

+// the center of the bounds

+//-----------------------------------------------------------------------------

+static void ComputeCenterMatrix( const Vector& origin, const QAngle& angles, 

+	const Vector& mins, const Vector& maxs, matrix3x4_t& matrix )

+{

+	Vector centroid;

+	VectorAdd( mins, maxs, centroid );

+	centroid *= 0.5f;

+	AngleMatrix( angles, matrix );

+

+	Vector worldCentroid;

+	VectorRotate( centroid, matrix, worldCentroid );

+	worldCentroid += origin;

+	MatrixSetColumn( worldCentroid, 3, matrix );

+}

+

+static void ComputeCenterIMatrix( const Vector& origin, const QAngle& angles, 

+	const Vector& mins, const Vector& maxs, matrix3x4_t& matrix )

+{

+	Vector centroid;

+	VectorAdd( mins, maxs, centroid );

+	centroid *= -0.5f;

+	AngleIMatrix( angles, matrix );

+

+	// For the translational component here, note that the origin in world space

+	// is T = R * C + O, (R = rotation matrix, C = centroid in local space, O = origin in world space)

+	// The IMatrix translation = - transpose(R) * T = -C - transpose(R) * 0

+	Vector localOrigin;

+	VectorRotate( origin, matrix, localOrigin );

+	centroid -= localOrigin;

+	MatrixSetColumn( centroid, 3, matrix );

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute a matrix which is the absolute value of another

+//-----------------------------------------------------------------------------

+static inline void ComputeAbsMatrix( const matrix3x4_t& in, matrix3x4_t& out )

+{

+	FloatBits(out[0][0]) = FloatAbsBits(in[0][0]);

+	FloatBits(out[0][1]) = FloatAbsBits(in[0][1]);

+	FloatBits(out[0][2]) = FloatAbsBits(in[0][2]);

+	FloatBits(out[1][0]) = FloatAbsBits(in[1][0]);

+	FloatBits(out[1][1]) = FloatAbsBits(in[1][1]);

+	FloatBits(out[1][2]) = FloatAbsBits(in[1][2]);

+	FloatBits(out[2][0]) = FloatAbsBits(in[2][0]);

+	FloatBits(out[2][1]) = FloatAbsBits(in[2][1]);

+	FloatBits(out[2][2]) = FloatAbsBits(in[2][2]);

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute a separating plane between two boxes (expensive!)

+// Returns false if no separating plane exists

+//-----------------------------------------------------------------------------

+static bool ComputeSeparatingPlane( const matrix3x4_t &worldToBox1, const matrix3x4_t &box2ToWorld, 

+	const Vector& box1Size, const Vector& box2Size, float tolerance, cplane_t* pPlane )

+{

+	// The various separating planes can be either

+	// 1) A plane parallel to one of the box face planes

+	// 2) A plane parallel to the cross-product of an edge from each box

+

+	// First, compute the basis of second box in the space of the first box

+	// NOTE: These basis place the origin at the centroid of each box!

+	matrix3x4_t	box2ToBox1;

+	ConcatTransforms( worldToBox1, box2ToWorld, box2ToBox1 );

+

+	// We're going to be using the origin of box2 in the space of box1 alot,

+	// lets extract it from the matrix....

+	Vector box2Origin;

+	MatrixGetColumn( box2ToBox1, 3, box2Origin );

+

+	// Next get the absolute values of these entries and store in absbox2ToBox1.

+	matrix3x4_t absBox2ToBox1;

+	ComputeAbsMatrix( box2ToBox1, absBox2ToBox1 );

+

+	// There are 15 tests to make.  The first 3 involve trying planes parallel

+	// to the faces of the first box.

+

+	// NOTE: The algorithm here involves finding the projections of the two boxes

+	// onto a particular line. If the projections on the line do not overlap,

+	// that means that there's a plane perpendicular to the line which separates 

+	// the two boxes; and we've therefore found a separating plane.

+

+	// The way we check for overlay is we find the projections of the two boxes

+	// onto the line, and add them up. We compare the sum with the projection

+	// of the relative center of box2 onto the same line.

+

+	Vector tmp;

+	float boxProjectionSum;

+	float originProjection;

+	

+	// NOTE: For these guys, we're taking advantage of the fact that the ith

+	// row of the box2ToBox1 is the direction of the box1 (x,y,z)-axis

+	// transformed into the space of box2.

+

+	// First side of box 1

+	boxProjectionSum = box1Size.x + MatrixRowDotProduct( absBox2ToBox1, 0, box2Size );

+	originProjection = FloatMakePositive( box2Origin.x ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		VectorCopy( worldToBox1[0], pPlane->normal.Base() );

+		return true;

+	}

+	

+	// Second side of box 1

+	boxProjectionSum = box1Size.y + MatrixRowDotProduct( absBox2ToBox1, 1, box2Size );

+	originProjection = FloatMakePositive( box2Origin.y ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		VectorCopy( worldToBox1[1], pPlane->normal.Base() );

+		return true;

+	}

+	

+	// Third side of box 1

+	boxProjectionSum = box1Size.z + MatrixRowDotProduct( absBox2ToBox1, 2, box2Size );

+	originProjection = FloatMakePositive( box2Origin.z ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		VectorCopy( worldToBox1[2], pPlane->normal.Base() );

+		return true;

+	}

+	

+	// The next three involve checking splitting planes parallel to the

+	// faces of the second box.

+

+	// NOTE: For these guys, we're taking advantage of the fact that the 0th

+	// column of the box2ToBox1 is the direction of the box2 x-axis

+	// transformed into the space of box1.

+	// Here, we're determining the distance of box2's center from box1's center

+	// by projecting it onto a line parallel to box2's axis

+	

+	// First side of box 2

+	boxProjectionSum = box2Size.x +	MatrixColumnDotProduct( absBox2ToBox1, 0, box1Size );

+	originProjection = FloatMakePositive( MatrixColumnDotProduct( box2ToBox1, 0, box2Origin ) ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		MatrixGetColumn( box2ToWorld, 0, pPlane->normal );	

+		return true;

+	}

+	

+	// Second side of box 2

+	boxProjectionSum = box2Size.y +	MatrixColumnDotProduct( absBox2ToBox1, 1, box1Size );

+	originProjection = FloatMakePositive( MatrixColumnDotProduct( box2ToBox1, 1, box2Origin ) ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		MatrixGetColumn( box2ToWorld, 1, pPlane->normal );	

+		return true;

+	}

+	

+	// Third side of box 2

+	boxProjectionSum = box2Size.z +	MatrixColumnDotProduct( absBox2ToBox1, 2, box1Size );

+	originProjection = FloatMakePositive( MatrixColumnDotProduct( box2ToBox1, 2, box2Origin ) ) + tolerance;

+	if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+	{

+		MatrixGetColumn( box2ToWorld, 2, pPlane->normal );	

+		return true;

+	}

+	

+	// Next check the splitting planes which are orthogonal to the pairs

+	// of edges, one from box1 and one from box2.  As only direction matters,

+	// there are 9 pairs since each box has 3 distinct edge directions.

+	

+	// Here, we take advantage of the fact that the edges from box 1 are all

+	// axis aligned; therefore the crossproducts are simplified. Let's walk through

+	// the example of b1e1 x b2e1:

+

+	// In this example, the line to check is perpendicular to b1e1 + b2e2

+	// we can compute this line by taking the cross-product:

+	//

+	// [  i  j  k ]

+	// [  1  0  0 ] = - ez j + ey k = l1

+	// [ ex ey ez ]

+

+	// Where ex, ey, ez is the components of box2's x axis in the space of box 1,

+	// which is == to the 0th column of of box2toBox1

+

+	// The projection of box1 onto this line = the absolute dot product of the box size

+	// against the line, which =

+	// AbsDot( box1Size, l1 ) = abs( -ez * box1.y ) + abs( ey * box1.z )

+

+	// To compute the projection of box2 onto this line, we'll do it in the space of box 2

+	//

+	// [  i  j  k ]

+	// [ fx fy fz ] = fz j - fy k = l2

+	// [  1  0  0 ]

+

+	// Where fx, fy, fz is the components of box1's x axis in the space of box 2,

+	// which is == to the 0th row of of box2toBox1

+

+	// The projection of box2 onto this line = the absolute dot product of the box size

+	// against the line, which =

+	// AbsDot( box2Size, l2 ) = abs( fz * box2.y ) + abs ( fy * box2.z )

+

+	// The projection of the relative origin position on this line is done in the 

+	// space of box 1:

+	//

+	// originProjection = DotProduct( <-ez j + ey k>, box2Origin ) =

+	//		-ez * box2Origin.y + ey * box2Origin.z

+

+	// NOTE: These checks can be bogus if both edges are parallel. The if

+	// checks at the beginning of each block are designed to catch that case

+	

+	// b1e1 x b2e1

+	if ( absBox2ToBox1[0][0] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.y * absBox2ToBox1[2][0] + box1Size.z * absBox2ToBox1[1][0] +

+			box2Size.y * absBox2ToBox1[0][2] + box2Size.z * absBox2ToBox1[0][1];

+		originProjection = FloatMakePositive( -box2Origin.y * box2ToBox1[2][0] + box2Origin.z * box2ToBox1[1][0] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 0, tmp );	

+			CrossProduct( worldToBox1[0], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e1 x b2e2

+	if ( absBox2ToBox1[0][1] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.y * absBox2ToBox1[2][1] + box1Size.z * absBox2ToBox1[1][1] +

+			box2Size.x * absBox2ToBox1[0][2] + box2Size.z * absBox2ToBox1[0][0];

+		originProjection = FloatMakePositive( -box2Origin.y * box2ToBox1[2][1] + box2Origin.z * box2ToBox1[1][1] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 1, tmp );	

+			CrossProduct( worldToBox1[0], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e1 x b2e3

+	if ( absBox2ToBox1[0][2] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.y * absBox2ToBox1[2][2] + box1Size.z * absBox2ToBox1[1][2] +

+			box2Size.x * absBox2ToBox1[0][1] + box2Size.y * absBox2ToBox1[0][0];

+		originProjection = FloatMakePositive( -box2Origin.y * box2ToBox1[2][2] + box2Origin.z * box2ToBox1[1][2] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 2, tmp );	

+			CrossProduct( worldToBox1[0], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e2 x b2e1

+	if ( absBox2ToBox1[1][0] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[2][0] + box1Size.z * absBox2ToBox1[0][0] +

+			box2Size.y * absBox2ToBox1[1][2] + box2Size.z * absBox2ToBox1[1][1];

+		originProjection = FloatMakePositive( box2Origin.x * box2ToBox1[2][0] - box2Origin.z * box2ToBox1[0][0] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 0, tmp );	

+			CrossProduct( worldToBox1[1], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e2 x b2e2

+	if ( absBox2ToBox1[1][1] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[2][1] + box1Size.z * absBox2ToBox1[0][1] +

+			box2Size.x * absBox2ToBox1[1][2] + box2Size.z * absBox2ToBox1[1][0];

+		originProjection = FloatMakePositive( box2Origin.x * box2ToBox1[2][1] - box2Origin.z * box2ToBox1[0][1] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 1, tmp );	

+			CrossProduct( worldToBox1[1], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e2 x b2e3

+	if ( absBox2ToBox1[1][2] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[2][2] + box1Size.z * absBox2ToBox1[0][2] +

+			box2Size.x * absBox2ToBox1[1][1] + box2Size.y * absBox2ToBox1[1][0];

+		originProjection = FloatMakePositive( box2Origin.x * box2ToBox1[2][2] - box2Origin.z * box2ToBox1[0][2] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 2, tmp );	

+			CrossProduct( worldToBox1[1], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e3 x b2e1

+	if ( absBox2ToBox1[2][0] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[1][0] + box1Size.y * absBox2ToBox1[0][0] +

+			box2Size.y * absBox2ToBox1[2][2] + box2Size.z * absBox2ToBox1[2][1];

+		originProjection = FloatMakePositive( -box2Origin.x * box2ToBox1[1][0] + box2Origin.y * box2ToBox1[0][0] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 0, tmp );	

+			CrossProduct( worldToBox1[2], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e3 x b2e2

+	if ( absBox2ToBox1[2][1] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[1][1] + box1Size.y * absBox2ToBox1[0][1] +

+			box2Size.x * absBox2ToBox1[2][2] + box2Size.z * absBox2ToBox1[2][0];

+		originProjection = FloatMakePositive( -box2Origin.x * box2ToBox1[1][1] + box2Origin.y * box2ToBox1[0][1] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 1, tmp );	

+			CrossProduct( worldToBox1[2], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+

+	// b1e3 x b2e3

+	if ( absBox2ToBox1[2][2] < 1.0f - 1e-3f )

+	{

+		boxProjectionSum =

+			box1Size.x * absBox2ToBox1[1][2] + box1Size.y * absBox2ToBox1[0][2] +

+			box2Size.x * absBox2ToBox1[2][1] + box2Size.y * absBox2ToBox1[2][0];

+		originProjection = FloatMakePositive( -box2Origin.x * box2ToBox1[1][2] + box2Origin.y * box2ToBox1[0][2] ) + tolerance;

+		if ( FloatBits(originProjection) > FloatBits(boxProjectionSum) )

+		{

+			MatrixGetColumn( box2ToWorld, 2, tmp );	

+			CrossProduct( worldToBox1[2], tmp.Base(), pPlane->normal.Base() ); 

+			return true;

+		}

+	}

+	return false;

+}

+

+

+//-----------------------------------------------------------------------------

+// Compute a separating plane between two boxes (expensive!)

+// Returns false if no separating plane exists

+//-----------------------------------------------------------------------------

+bool ComputeSeparatingPlane( const Vector& org1, const QAngle& angles1, const Vector& min1, const Vector& max1, 

+	const Vector& org2, const QAngle& angles2, const Vector& min2, const Vector& max2, 

+	float tolerance, cplane_t* pPlane )

+{

+	matrix3x4_t	worldToBox1, box2ToWorld;

+	ComputeCenterIMatrix( org1, angles1, min1, max1, worldToBox1 );

+	ComputeCenterMatrix( org2, angles2, min2, max2, box2ToWorld );

+

+	// Then compute the size of the two boxes

+	Vector box1Size, box2Size;

+	VectorSubtract( max1, min1, box1Size );

+	VectorSubtract( max2, min2, box2Size );

+	box1Size *= 0.5f;

+	box2Size *= 0.5f;

+

+	return ComputeSeparatingPlane( worldToBox1, box2ToWorld, box1Size, box2Size, tolerance, pPlane );

+}

+

+

+//-----------------------------------------------------------------------------

+// Swept OBB test

+//-----------------------------------------------------------------------------

+bool IsRayIntersectingOBB( const Ray_t &ray, const Vector& org, const QAngle& angles, 

+						  const Vector& mins, const Vector& maxs )

+{

+	if ( angles == vec3_angle )

+	{

+		Vector vecWorldMins, vecWorldMaxs;

+		VectorAdd( org, mins, vecWorldMins );

+		VectorAdd( org, maxs, vecWorldMaxs );

+		return IsBoxIntersectingRay( vecWorldMins, vecWorldMaxs, ray ); 

+	}

+

+	if ( ray.m_IsRay )

+	{

+		matrix3x4_t worldToBox;

+		AngleIMatrix( angles, org, worldToBox );

+

+		Ray_t rotatedRay;

+		VectorTransform( ray.m_Start, worldToBox, rotatedRay.m_Start );

+		VectorRotate( ray.m_Delta, worldToBox, rotatedRay.m_Delta );

+		rotatedRay.m_StartOffset = vec3_origin;

+		rotatedRay.m_Extents = vec3_origin;

+		rotatedRay.m_IsRay = ray.m_IsRay;

+		rotatedRay.m_IsSwept = ray.m_IsSwept;

+

+		return IsBoxIntersectingRay( mins, maxs, rotatedRay ); 

+	}

+

+	if ( !ray.m_IsSwept )

+	{

+		cplane_t plane;

+		return ComputeSeparatingPlane( ray.m_Start, vec3_angle, -ray.m_Extents, ray.m_Extents,

+			org, angles, mins, maxs, 0.0f, &plane ) == false;

+	}

+

+	// NOTE: See the comments in ComputeSeparatingPlane to understand this math

+

+	// First, compute the basis of box in the space of the ray

+	// NOTE: These basis place the origin at the centroid of each box!

+	matrix3x4_t	worldToBox1, box2ToWorld;

+	ComputeCenterMatrix( org, angles, mins, maxs, box2ToWorld );

+

+	// Find the center + extents of an AABB surrounding the ray

+	Vector vecRayCenter;

+	VectorMA( ray.m_Start, 0.5, ray.m_Delta, vecRayCenter );

+	vecRayCenter *= -1.0f;

+	SetIdentityMatrix( worldToBox1 );

+	MatrixSetColumn( vecRayCenter, 3, worldToBox1 );

+

+	Vector box1Size;

+	box1Size.x = ray.m_Extents.x + FloatMakePositive( ray.m_Delta.x ) * 0.5f;

+	box1Size.y = ray.m_Extents.y + FloatMakePositive( ray.m_Delta.y ) * 0.5f;

+	box1Size.z = ray.m_Extents.z + FloatMakePositive( ray.m_Delta.z ) * 0.5f;

+

+	// Then compute the size of the box

+	Vector box2Size;

+	VectorSubtract( maxs, mins, box2Size );

+	box2Size *= 0.5f;

+

+	// Do an OBB test of the box with the AABB surrounding the ray

+	cplane_t plane;

+	if ( ComputeSeparatingPlane( worldToBox1, box2ToWorld, box1Size, box2Size, 0.0f, &plane ) )

+		return false;

+

+	// Now deal with the planes which are the cross products of the ray sweep direction vs box edges

+	Vector vecRayDirection = ray.m_Delta;

+	VectorNormalize( vecRayDirection );

+

+	// Need a vector between ray center vs box center measured in the space of the ray (world)

+	Vector vecCenterDelta;

+	vecCenterDelta.x = box2ToWorld[0][3] - ray.m_Start.x;

+	vecCenterDelta.y = box2ToWorld[1][3] - ray.m_Start.y;

+	vecCenterDelta.z = box2ToWorld[2][3] - ray.m_Start.z;

+

+	// Rotate the ray direction into the space of the OBB

+	Vector vecAbsRayDirBox2;

+	VectorIRotate( vecRayDirection, box2ToWorld, vecAbsRayDirBox2 );

+

+	// Make abs versions of the ray in world space + ray in box2 space

+	VectorAbs( vecAbsRayDirBox2, vecAbsRayDirBox2 );

+

+	// Now do the work for the planes which are perpendicular to the edges of the AABB

+	// and the sweep direction edges...

+

+	// In this example, the line to check is perpendicular to box edge x + ray delta

+	// we can compute this line by taking the cross-product:

+	//

+	// [  i  j  k ]

+	// [  1  0  0 ] = - dz j + dy k = l1

+	// [ dx dy dz ]

+

+	// Where dx, dy, dz is the ray delta (normalized)

+

+	// The projection of the box onto this line = the absolute dot product of the box size

+	// against the line, which =

+	// AbsDot( vecBoxHalfDiagonal, l1 ) = abs( -dz * vecBoxHalfDiagonal.y ) + abs( dy * vecBoxHalfDiagonal.z )

+

+	// Because the plane contains the sweep direction, the sweep will produce

+	// no extra projection onto the line normal to the plane. 

+	// Therefore all we need to do is project the ray extents onto this line also:

+	// AbsDot( ray.m_Extents, l1 ) = abs( -dz * ray.m_Extents.y ) + abs( dy * ray.m_Extents.z )

+

+	Vector vecPlaneNormal;

+

+	// box x x ray delta

+	CrossProduct( vecRayDirection, Vector( box2ToWorld[0][0], box2ToWorld[1][0], box2ToWorld[2][0] ), vecPlaneNormal );

+	float flCenterDeltaProjection = FloatMakePositive( DotProduct( vecPlaneNormal, vecCenterDelta ) );

+	float flBoxProjectionSum = 

+		vecAbsRayDirBox2.z * box2Size.y + vecAbsRayDirBox2.y * box2Size.z +

+		DotProductAbs( vecPlaneNormal, ray.m_Extents );

+	if ( FloatBits(flCenterDeltaProjection) > FloatBits(flBoxProjectionSum) )

+		return false;

+

+	// box y x ray delta

+	CrossProduct( vecRayDirection, Vector( box2ToWorld[0][1], box2ToWorld[1][1], box2ToWorld[2][1] ), vecPlaneNormal );

+	flCenterDeltaProjection = FloatMakePositive( DotProduct( vecPlaneNormal, vecCenterDelta ) );

+	flBoxProjectionSum = 

+		vecAbsRayDirBox2.z * box2Size.x + vecAbsRayDirBox2.x * box2Size.z +

+		DotProductAbs( vecPlaneNormal, ray.m_Extents );

+	if ( FloatBits(flCenterDeltaProjection) > FloatBits(flBoxProjectionSum) )

+		return false;

+

+	// box z x ray delta

+	CrossProduct( vecRayDirection, Vector( box2ToWorld[0][2], box2ToWorld[1][2], box2ToWorld[2][2] ), vecPlaneNormal );

+	flCenterDeltaProjection = FloatMakePositive( DotProduct( vecPlaneNormal, vecCenterDelta ) );

+	flBoxProjectionSum = 

+		vecAbsRayDirBox2.y * box2Size.x + vecAbsRayDirBox2.x * box2Size.y +

+		DotProductAbs( vecPlaneNormal, ray.m_Extents );

+	if ( FloatBits(flCenterDeltaProjection) > FloatBits(flBoxProjectionSum) )

+		return false;

+	

+	return true;

+}

+

+//--------------------------------------------------------------------------

+// Purpose:

+//

+// NOTE:

+//	triangle points are given in clockwise order (aabb-triangle test)

+//

+//    1				edge0 = 1 - 0

+//    | \           edge1 = 2 - 1

+//    |  \          edge2 = 0 - 2

+//    |   \			.

+//    |    \		.

+//    0-----2		.

+//

+//--------------------------------------------------------------------------

+

+//-----------------------------------------------------------------------------

+// Purpose: find the minima and maxima of the 3 given values

+//-----------------------------------------------------------------------------

+inline void FindMinMax( float v1, float v2, float v3, float &min, float &max )

+{

+	min = max = v1;

+	if ( v2 < min ) { min = v2; }

+	if ( v2 > max ) { max = v2; }

+	if ( v3 < min ) { min = v3; }

+	if ( v3 > max ) { max = v3; }

+}

+

+//-----------------------------------------------------------------------------

+// Purpose:

+//-----------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossX2( float flEdgeZ, float flEdgeY, float flAbsEdgeZ, float flAbsEdgeY,

+							     const Vector &p1, const Vector &p3, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialX(1,0,0) x edge ): x = 0.0f, y = edge.z, z = -edge.y

+	// Triangle Point Distances: dist(x) = normal.y * pt(x).y + normal.z * pt(x).z

+	float flDist1 = flEdgeZ * p1.y - flEdgeY * p1.z;

+	float flDist3 = flEdgeZ * p3.y - flEdgeY * p3.z;

+

+	// Extents are symmetric: dist = abs( normal.y ) * extents.y + abs( normal.z ) * extents.z

+	float flDistBox = flAbsEdgeZ * vecExtents.y + flAbsEdgeY * vecExtents.z;

+

+	// Either dist1, dist3 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist1 < flDist3 )

+	{

+		if ( ( flDist1 > ( flDistBox + flTolerance ) ) || ( flDist3 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+	else

+	{

+		if ( ( flDist3 > ( flDistBox + flTolerance ) ) || ( flDist1 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//--------------------------------------------------------------------------

+// Purpose:

+//--------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossX3( float flEdgeZ, float flEdgeY, float flAbsEdgeZ, float flAbsEdgeY,

+								 const Vector &p1, const Vector &p2, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialX(1,0,0) x edge ): x = 0.0f, y = edge.z, z = -edge.y 

+	// Triangle Point Distances: dist(x) = normal.y * pt(x).y + normal.z * pt(x).z

+	float flDist1 = flEdgeZ * p1.y - flEdgeY * p1.z;

+	float flDist2 = flEdgeZ * p2.y - flEdgeY * p2.z;

+

+	// Extents are symmetric: dist = abs( normal.y ) * extents.y + abs( normal.z ) * extents.z

+	float flDistBox = flAbsEdgeZ * vecExtents.y + flAbsEdgeY * vecExtents.z;

+

+	// Either dist1, dist2 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist1 < flDist2 )

+	{

+		if ( ( flDist1 > ( flDistBox + flTolerance ) ) || ( flDist2 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+	else

+	{

+		if ( ( flDist2 > ( flDistBox + flTolerance ) ) || ( flDist1 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//--------------------------------------------------------------------------

+//--------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossY2( float flEdgeZ, float flEdgeX, float flAbsEdgeZ, float flAbsEdgeX,

+								 const Vector &p1, const Vector &p3, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialY(0,1,0) x edge ): x = -edge.z, y = 0.0f, z = edge.x

+	// Triangle Point Distances: dist(x) = normal.x * pt(x).x + normal.z * pt(x).z

+	float flDist1 = -flEdgeZ * p1.x + flEdgeX * p1.z;

+	float flDist3 = -flEdgeZ * p3.x + flEdgeX * p3.z;

+

+	// Extents are symmetric: dist = abs( normal.x ) * extents.x + abs( normal.z ) * extents.z

+	float flDistBox = flAbsEdgeZ * vecExtents.x + flAbsEdgeX * vecExtents.z;

+

+	// Either dist1, dist3 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist1 < flDist3 )

+	{

+		if ( ( flDist1 > ( flDistBox + flTolerance ) ) || ( flDist3 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+	else

+	{

+		if ( ( flDist3 > ( flDistBox + flTolerance ) ) || ( flDist1 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//--------------------------------------------------------------------------

+//--------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossY3( float flEdgeZ, float flEdgeX, float flAbsEdgeZ, float flAbsEdgeX,

+								 const Vector &p1, const Vector &p2, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialY(0,1,0) x edge ): x = -edge.z, y = 0.0f, z = edge.x

+	// Triangle Point Distances: dist(x) = normal.x * pt(x).x + normal.z * pt(x).z

+	float flDist1 = -flEdgeZ * p1.x + flEdgeX * p1.z;

+	float flDist2 = -flEdgeZ * p2.x + flEdgeX * p2.z;

+

+	// Extents are symmetric: dist = abs( normal.x ) * extents.x + abs( normal.z ) * extents.z

+	float flDistBox = flAbsEdgeZ * vecExtents.x + flAbsEdgeX * vecExtents.z;

+

+	// Either dist1, dist2 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist1 < flDist2 )

+	{

+		if ( ( flDist1 > ( flDistBox + flTolerance ) ) || ( flDist2 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+	else

+	{

+		if ( ( flDist2 > ( flDistBox + flTolerance ) ) || ( flDist1 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//--------------------------------------------------------------------------

+//--------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossZ1( float flEdgeY, float flEdgeX, float flAbsEdgeY, float flAbsEdgeX,

+								 const Vector &p2, const Vector &p3, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialZ(0,0,1) x edge ): x = edge.y, y = -edge.x, z = 0.0f

+	// Triangle Point Distances: dist(x) = normal.x * pt(x).x + normal.y * pt(x).y

+	float flDist2 = flEdgeY * p2.x - flEdgeX * p2.y;

+	float flDist3 = flEdgeY * p3.x - flEdgeX * p3.y;

+

+	// Extents are symmetric: dist = abs( normal.x ) * extents.x + abs( normal.y ) * extents.y

+	float flDistBox = flAbsEdgeY * vecExtents.x + flAbsEdgeX * vecExtents.y; 

+

+	// Either dist2, dist3 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist3 < flDist2 )

+	{

+		if ( ( flDist3 > ( flDistBox + flTolerance ) ) || ( flDist2 < -( flDistBox + flTolerance ) ) ) 

+			return false;

+	}

+	else

+	{

+		if ( ( flDist2 > ( flDistBox + flTolerance ) ) || ( flDist3 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//--------------------------------------------------------------------------

+//--------------------------------------------------------------------------

+inline bool AxisTestEdgeCrossZ2( float flEdgeY, float flEdgeX, float flAbsEdgeY, float flAbsEdgeX,

+								 const Vector &p1, const Vector &p3, const Vector &vecExtents,

+								 float flTolerance )

+{

+	// Cross Product( axialZ(0,0,1) x edge ): x = edge.y, y = -edge.x, z = 0.0f

+	// Triangle Point Distances: dist(x) = normal.x * pt(x).x + normal.y * pt(x).y

+	float flDist1 = flEdgeY * p1.x - flEdgeX * p1.y;

+	float flDist3 = flEdgeY * p3.x - flEdgeX * p3.y;

+

+	// Extents are symmetric: dist = abs( normal.x ) * extents.x + abs( normal.y ) * extents.y

+	float flDistBox = flAbsEdgeY * vecExtents.x + flAbsEdgeX * vecExtents.y; 

+

+	// Either dist1, dist3 is the closest point to the box, determine which and test of overlap with box(AABB).

+	if ( flDist1 < flDist3 )

+	{

+		if ( ( flDist1 > ( flDistBox + flTolerance ) ) || ( flDist3 < -( flDistBox + flTolerance ) ) ) 

+			return false;

+	}

+	else

+	{

+		if ( ( flDist3 > ( flDistBox + flTolerance ) ) || ( flDist1 < -( flDistBox + flTolerance ) ) )

+			return false;

+	}

+

+	return true;

+}

+

+//-----------------------------------------------------------------------------

+// Purpose: Test for an intersection (overlap) between an axial-aligned bounding 

+//          box (AABB) and a triangle.

+//

+// Using the "Separating-Axis Theorem" to test for intersections between

+// a triangle and an axial-aligned bounding box (AABB).

+// 1. 3 Axis Planes - x, y, z

+// 2. 9 Edge Planes Tests - the 3 edges of the triangle crossed with all 3 axial 

+//                          planes (x, y, z)

+// 3. 1 Face Plane - the triangle plane (cplane_t plane below)

+// Output: false = separating axis (no intersection)

+//         true = intersection

+//-----------------------------------------------------------------------------

+bool IsBoxIntersectingTriangle( const Vector &vecBoxCenter, const Vector &vecBoxExtents,

+						        const Vector &v1, const Vector &v2, const Vector &v3,

+						        const cplane_t &plane, float flTolerance )

+{

+	// Test the axial planes (x,y,z) against the min, max of the triangle.

+	float flMin, flMax;

+	Vector p1, p2, p3;

+

+	// x plane

+	p1.x = v1.x - vecBoxCenter.x;

+	p2.x = v2.x - vecBoxCenter.x;

+	p3.x = v3.x - vecBoxCenter.x;

+	FindMinMax( p1.x, p2.x, p3.x, flMin, flMax );

+	if ( ( flMin > ( vecBoxExtents.x + flTolerance ) ) || ( flMax < -( vecBoxExtents.x + flTolerance ) ) ) 

+		return false; 

+

+	// y plane

+	p1.y = v1.y - vecBoxCenter.y;

+	p2.y = v2.y - vecBoxCenter.y;

+	p3.y = v3.y - vecBoxCenter.y;

+	FindMinMax( p1.y, p2.y, p3.y, flMin, flMax );

+	if ( ( flMin > ( vecBoxExtents.y + flTolerance ) ) || ( flMax < -( vecBoxExtents.y + flTolerance ) ) ) 

+		return false; 

+

+	// z plane

+	p1.z = v1.z - vecBoxCenter.z;

+	p2.z = v2.z - vecBoxCenter.z;

+	p3.z = v3.z - vecBoxCenter.z;

+	FindMinMax( p1.z, p2.z, p3.z, flMin, flMax );

+	if ( ( flMin > ( vecBoxExtents.z + flTolerance ) ) || ( flMax < -( vecBoxExtents.z + flTolerance ) ) ) 

+		return false; 

+

+	// Test the 9 edge cases.

+	Vector vecEdge, vecAbsEdge;

+

+	// edge 0 (cross x,y,z)

+	vecEdge = p2 - p1;

+	vecAbsEdge.y = FloatMakePositive( vecEdge.y );

+	vecAbsEdge.z = FloatMakePositive( vecEdge.z );

+	if ( !AxisTestEdgeCrossX2( vecEdge.z, vecEdge.y, vecAbsEdge.z, vecAbsEdge.y, p1, p3, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	vecAbsEdge.x = FloatMakePositive( vecEdge.x );

+	if ( !AxisTestEdgeCrossY2( vecEdge.z, vecEdge.x, vecAbsEdge.z, vecAbsEdge.x, p1, p3, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	if ( !AxisTestEdgeCrossZ1( vecEdge.y, vecEdge.x, vecAbsEdge.y, vecAbsEdge.x, p2, p3, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	// edge 1 (cross x,y,z)

+	vecEdge = p3 - p2;

+	vecAbsEdge.y = FloatMakePositive( vecEdge.y );

+	vecAbsEdge.z = FloatMakePositive( vecEdge.z );

+	if ( !AxisTestEdgeCrossX2( vecEdge.z, vecEdge.y, vecAbsEdge.z, vecAbsEdge.y, p1, p2, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	vecAbsEdge.x = FloatMakePositive( vecEdge.x );

+	if ( !AxisTestEdgeCrossY2( vecEdge.z, vecEdge.x, vecAbsEdge.z, vecAbsEdge.x, p1, p2, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	if ( !AxisTestEdgeCrossZ2( vecEdge.y, vecEdge.x, vecAbsEdge.y, vecAbsEdge.x, p1, p3, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	// edge 2 (cross x,y,z)

+	vecEdge = p1 - p3;

+	vecAbsEdge.y = FloatMakePositive( vecEdge.y );

+	vecAbsEdge.z = FloatMakePositive( vecEdge.z );

+	if ( !AxisTestEdgeCrossX3( vecEdge.z, vecEdge.y, vecAbsEdge.z, vecAbsEdge.y, p1, p2, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	vecAbsEdge.x = FloatMakePositive( vecEdge.x );

+	if ( !AxisTestEdgeCrossY3( vecEdge.z, vecEdge.x, vecAbsEdge.z, vecAbsEdge.x, p1, p2, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	if ( !AxisTestEdgeCrossZ1( vecEdge.y, vecEdge.x, vecAbsEdge.y, vecAbsEdge.x, p2, p3, vecBoxExtents, flTolerance ) ) 

+		return false; 

+

+	// Test against the triangle face plane.

+	Vector vecMin, vecMax;

+	VectorSubtract( vecBoxCenter, vecBoxExtents, vecMin );

+	VectorAdd( vecBoxCenter, vecBoxExtents, vecMax );

+	if ( BoxOnPlaneSide( vecMin, vecMax, &plane ) != 3 ) 

+		return false; 

+

+	return true;

+}

+

+// NOTE: JAY: This is untested code based on Real-time Collision Detection by Ericson

+#if 0

+Vector CalcClosestPointOnTriangle( const Vector &P, const Vector &v0, const Vector &v1, const Vector &v2 )

+{

+	Vector e0 = v1 - v0;

+	Vector e1 = v2 - v0;

+	Vector p0 = P - v0;

+

+	// voronoi region of v0

+	float d1 = DotProduct( e0, p0 );

+	float d2 = DotProduct( e1, p0 );

+	if (d1 <= 0.0f && d2 <= 0.0f)

+		return v0;

+

+	// voronoi region of v1

+	Vector p1 = P - v1;

+	float d3 = DotProduct( e0, p1 );

+	float d4 = DotProduct( e1, p1 );

+	if (d3 >=0.0f && d4 <= d3)

+		return v1;

+

+	// voronoi region of e0 (v0-v1)

+	float ve2 = d1*d4 - d3*d2;

+	if ( ve2 <= 0.0f && d1 >= 0.0f && d3 <= 0.0f )

+	{

+		float v = d1 / (d1-d3);

+		return v0 + v * e0;

+	}

+	// voronoi region of v2

+	Vector p2 = P - v2;

+	float d5 = DotProduct( e0, p2 );

+	float d6 = DotProduct( e1, p2 );

+	if (d6 >= 0.0f && d5 <= d6)

+		return v2;

+	// voronoi region of e1

+	float ve1 = d5*d2 - d1*d6;

+	if (ve1 <= 0.0f && d2 >= 0.0f && d6 >= 0.0f)

+	{

+		float w = d2 / (d2-d6);

+		return v0 + w * e1;

+	}

+	// voronoi region on e2

+	float ve0 = d3*d6 - d5*d4;

+	if ( ve0 <= 0.0f && (d4-d3) >= 0.0f && (d5-d6) >= 0.0f )

+	{

+		float w = (d4-d3)/((d4-d3) + (d5-d6));

+		return v1 + w * (v2-v1);

+	}

+	// voronoi region of v0v1v2 triangle

+	float denom = 1.0f / (ve0+ve1+ve2);

+	float v = ve1*denom;

+	float w = ve2 * denom;

+	return v0 + e0 * v + e1 * w;

+}

+#endif

+

+

+bool OBBHasFullyContainedIntersectionWithQuad( const Vector &vOBBExtent1_Scaled, const Vector &vOBBExtent2_Scaled, const Vector &vOBBExtent3_Scaled, const Vector &ptOBBCenter,

+											  const Vector &vQuadNormal, float fQuadPlaneDist, const Vector &ptQuadCenter,

+											  const Vector &vQuadExtent1_Normalized, float fQuadExtent1Length, 

+											  const Vector &vQuadExtent2_Normalized, float fQuadExtent2Length )

+{

+	Vector ptOBB[8]; //this specific ordering helps us web out from a point to its 3 connecting points with some bit math (most importantly, no if's)

+	ptOBB[0] = ptOBBCenter - vOBBExtent1_Scaled - vOBBExtent2_Scaled - vOBBExtent3_Scaled;

+	ptOBB[1] = ptOBBCenter - vOBBExtent1_Scaled - vOBBExtent2_Scaled + vOBBExtent3_Scaled;

+	ptOBB[2] = ptOBBCenter - vOBBExtent1_Scaled + vOBBExtent2_Scaled + vOBBExtent3_Scaled;

+	ptOBB[3] = ptOBBCenter - vOBBExtent1_Scaled + vOBBExtent2_Scaled - vOBBExtent3_Scaled;

+	ptOBB[4] = ptOBBCenter + vOBBExtent1_Scaled - vOBBExtent2_Scaled - vOBBExtent3_Scaled;

+	ptOBB[5] = ptOBBCenter + vOBBExtent1_Scaled - vOBBExtent2_Scaled + vOBBExtent3_Scaled;

+	ptOBB[6] = ptOBBCenter + vOBBExtent1_Scaled + vOBBExtent2_Scaled + vOBBExtent3_Scaled;

+	ptOBB[7] = ptOBBCenter + vOBBExtent1_Scaled + vOBBExtent2_Scaled - vOBBExtent3_Scaled;

+

+	float fDists[8];

+	for( int i = 0; i != 8; ++i )

+		fDists[i] = vQuadNormal.Dot( ptOBB[i] ) - fQuadPlaneDist;

+

+	int iSides[8];

+	int iSideMask = 0;

+	for( int i = 0; i != 8; ++i )

+	{

+		if( fDists[i] > 0.0f )

+		{

+			iSides[i] = 1;

+			iSideMask |= 1;

+		}

+		else

+		{

+			iSides[i] = 2;

+			iSideMask |= 2;

+		}

+	}

+

+	if( iSideMask != 3 ) //points reside entirely on one side of the quad's plane

+		return false;

+

+	Vector ptPlaneIntersections[12]; //only have 12 lines, can only possibly generate 12 split points

+	int iPlaneIntersectionsCount = 0;

+

+	for( int i = 0; i != 8; ++i )

+	{

+		if( iSides[i] == 2 ) //point behind the plane

+		{

+			int iAxisCrossings[3];

+			iAxisCrossings[0] = i ^ 4; //upper 4 vs lower 4 crosses vOBBExtent1 axis

+			iAxisCrossings[1] = ((i + 1) & 3) + (i & 4); //cycle to the next element while staying within the upper 4 or lower 4, this will cross either vOBBExtent2 or vOBBExtent3 axis, we don't care which

+			iAxisCrossings[2] = ((i - 1) & 3) + (i & 4); //cylce to the previous element while staying within the upper 4 or lower 4, this will cross the axis iAxisCrossings[1] didn't cross

+

+			for( int j = 0; j != 3; ++j )

+			{

+				if( iSides[iAxisCrossings[j]] == 1 ) //point in front of the plane

+				{

+					//line between ptOBB[i] and ptOBB[iAxisCrossings[j]] intersects the plane, generate a point at the intersection for further testing

+					float fTotalDist = fDists[iAxisCrossings[j]] - fDists[i]; //remember that fDists[i] is a negative value

+					ptPlaneIntersections[iPlaneIntersectionsCount] = (ptOBB[iAxisCrossings[j]] * (-fDists[i]/fTotalDist)) + (ptOBB[i] * (fDists[iAxisCrossings[j]]/fTotalDist));

+

+					Assert( fabs( ptPlaneIntersections[iPlaneIntersectionsCount].Dot( vQuadNormal ) - fQuadPlaneDist ) < 0.1f ); //intersection point is on plane

+

+					++iPlaneIntersectionsCount;

+				}

+			}

+		}

+	}

+

+	Assert( iPlaneIntersectionsCount != 0 );

+

+	for( int i = 0; i != iPlaneIntersectionsCount; ++i )

+	{

+		//these points are guaranteed to be on the plane, now just check to see if they're within the quad's extents

+		Vector vToPointFromQuadCenter = ptPlaneIntersections[i] - ptQuadCenter;

+

+		float fExt1Dist = vQuadExtent1_Normalized.Dot( vToPointFromQuadCenter );

+		if( fabs( fExt1Dist ) > fQuadExtent1Length )

+			return false; //point is outside boundaries

+

+		//vToPointFromQuadCenter -= vQuadExtent1_Normalized * fExt1Dist; //to handle diamond shaped quads

+

+		float fExt2Dist = vQuadExtent2_Normalized.Dot( vToPointFromQuadCenter );

+		if( fabs( fExt2Dist ) > fQuadExtent2Length )

+			return false; //point is outside boundaries

+	}

+

+	return true; //there were lines crossing the quad plane, and every line crossing that plane had its intersection with the plane within the quad's boundaries

+}

+

+//-----------------------------------------------------------------------------

+// Compute if the Ray intersects the quad plane, and whether the entire

+// Ray/Quad intersection is contained within the quad itself

+//

+// False if no intersection exists, or if part of the intersection is

+// outside the quad's extents

+//-----------------------------------------------------------------------------

+bool RayHasFullyContainedIntersectionWithQuad( const Ray_t &ray,

+											  const Vector &vQuadNormal, float fQuadPlaneDist, const Vector &ptQuadCenter,

+											  const Vector &vQuadExtent1_Normalized, float fQuadExtent1Length, 

+											  const Vector &vQuadExtent2_Normalized, float fQuadExtent2Length )

+{

+	Vector ptPlaneIntersections[(12 + 12 + 8)]; //absolute max possible: 12 lines to connect the start box, 12 more to connect the end box, 8 to connect the boxes to eachother

+	

+	//8 points to make an AABB, 8 lines to connect each point from it's start to end point along the ray, 8 possible intersections

+	int iPlaneIntersectionsCount = 0;

+

+	if( ray.m_IsRay )

+	{

+		//just 1 line

+		if( ray.m_IsSwept )

+		{

+			Vector ptEndPoints[2];

+			ptEndPoints[0] = ray.m_Start;

+			ptEndPoints[1] = ptEndPoints[0] + ray.m_Delta;

+

+			int i;

+			float fDists[2];

+			for( i = 0; i != 2; ++i )

+				fDists[i] = vQuadNormal.Dot( ptEndPoints[i] ) - fQuadPlaneDist;

+	       

+			for( i = 0; i != 2; ++i )

+			{

+				if( fDists[i] <= 0.0f )

+				{

+					int j = 1-i;

+					if( fDists[j] >= 0.0f )

+					{

+						float fInvTotalDist = 1.0f / (fDists[j] - fDists[i]); //fDists[i] <= 0, ray is swept so no chance that the denom was 0

+						ptPlaneIntersections[0] = (ptEndPoints[i] * (fDists[j] * fInvTotalDist)) - (ptEndPoints[j] * (fDists[i] * fInvTotalDist)); //fDists[i] <= 0 

+						Assert( fabs( ptPlaneIntersections[iPlaneIntersectionsCount].Dot( vQuadNormal ) - fQuadPlaneDist ) < 0.1f ); //intersection point is on plane

+						iPlaneIntersectionsCount = 1;

+					}

+					else 

+					{

+						return false;

+					}

+					break;

+				}

+			}

+

+			if( i == 2 )

+				return false;

+		}

+		else //not swept, so this is actually a point on quad question

+		{

+			if( fabs( vQuadNormal.Dot( ray.m_Start ) - fQuadPlaneDist ) < 1e-6 )

+			{

+				ptPlaneIntersections[0] = ray.m_Start;

+				iPlaneIntersectionsCount = 1;

+			}

+			else

+			{

+				return false;

+			}

+		}

+	}

+	else

+	{

+		Vector ptEndPoints[2][8];

+		//this specific ordering helps us web out from a point to its 3 connecting points with some bit math (most importantly, no if's)

+		ptEndPoints[0][0] = ray.m_Start; ptEndPoints[0][0].x -= ray.m_Extents.x; ptEndPoints[0][0].y -= ray.m_Extents.y; ptEndPoints[0][0].z -= ray.m_Extents.z;

+		ptEndPoints[0][1] = ray.m_Start; ptEndPoints[0][1].x -= ray.m_Extents.x; ptEndPoints[0][1].y -= ray.m_Extents.y; ptEndPoints[0][1].z += ray.m_Extents.z;

+		ptEndPoints[0][2] = ray.m_Start; ptEndPoints[0][2].x -= ray.m_Extents.x; ptEndPoints[0][2].y += ray.m_Extents.y; ptEndPoints[0][2].z += ray.m_Extents.z;

+		ptEndPoints[0][3] = ray.m_Start; ptEndPoints[0][3].x -= ray.m_Extents.x; ptEndPoints[0][3].y += ray.m_Extents.y; ptEndPoints[0][3].z -= ray.m_Extents.z;

+		ptEndPoints[0][4] = ray.m_Start; ptEndPoints[0][4].x += ray.m_Extents.x; ptEndPoints[0][4].y -= ray.m_Extents.y; ptEndPoints[0][4].z -= ray.m_Extents.z;

+		ptEndPoints[0][5] = ray.m_Start; ptEndPoints[0][5].x += ray.m_Extents.x; ptEndPoints[0][5].y -= ray.m_Extents.y; ptEndPoints[0][5].z += ray.m_Extents.z;

+		ptEndPoints[0][6] = ray.m_Start; ptEndPoints[0][6].x += ray.m_Extents.x; ptEndPoints[0][6].y += ray.m_Extents.y; ptEndPoints[0][6].z += ray.m_Extents.z;

+		ptEndPoints[0][7] = ray.m_Start; ptEndPoints[0][7].x += ray.m_Extents.x; ptEndPoints[0][7].y += ray.m_Extents.y; ptEndPoints[0][7].z -= ray.m_Extents.z;

+

+		float fDists[2][8];

+		int iSides[2][8];

+		int iSideMask[2] = { 0, 0 };

+		for( int i = 0; i != 8; ++i )

+		{

+			fDists[0][i] = vQuadNormal.Dot( ptEndPoints[0][i] ) - fQuadPlaneDist;

+			if( fDists[0][i] > 0.0f )

+			{

+				iSides[0][i] = 1;

+				iSideMask[0] |= 1;

+			}

+			else

+			{

+				iSides[0][i] = 2;

+				iSideMask[0] |= 2;

+			}

+		}

+

+		if( ray.m_IsSwept )

+		{

+			for( int i = 0; i != 8; ++i )

+				ptEndPoints[1][i] = ptEndPoints[0][i] + ray.m_Delta;

+

+			for( int i = 0; i != 8; ++i )

+			{

+				fDists[1][i] = vQuadNormal.Dot( ptEndPoints[1][i] ) - fQuadPlaneDist;

+				if( fDists[1][i] > 0.0f )

+				{

+					iSides[1][i] = 1;

+					iSideMask[1] |= 1;

+				}

+				else

+				{

+					iSides[1][i] = 2;

+					iSideMask[1] |= 2;

+				}

+			}

+		}

+

+		if( (iSideMask[0] | iSideMask[1]) != 3 )

+		{

+			//Assert( (iSideMask[0] | iSideMask[1]) != 2 );

+			return false; //all points resides entirely on one side of the quad

+		}

+

+

+		//generate intersections for boxes split by the plane at either end of the ray

+		for( int k = 0; k != 2; ++k )

+		{

+			if( iSideMask[k] == 3 ) //box is split by the plane

+			{

+				for( int i = 0; i != 8; ++i )

+				{

+					if( iSides[k][i] == 2 ) //point behind the plane

+					{

+						int iAxisCrossings[3];

+						iAxisCrossings[0] = i ^ 4; //upper 4 vs lower 4 crosses X axis

+						iAxisCrossings[1] = ((i + 1) & 3) + (i & 4); //cycle to the next element while staying within the upper 4 or lower 4, this will cross either Y or Z axis, we don't care which

+						iAxisCrossings[2] = ((i - 1) & 3) + (i & 4); //cylce to the previous element while staying within the upper 4 or lower 4, this will cross the axis iAxisCrossings[1] didn't cross

+

+						for( int j = 0; j != 3; ++j )

+						{

+							if( iSides[k][iAxisCrossings[j]] == 1 ) //point in front of the plane

+							{

+								//line between ptEndPoints[i] and ptEndPoints[iAxisCrossings[j]] intersects the plane, generate a point at the intersection for further testing

+								float fInvTotalDist = 1.0f / (fDists[k][iAxisCrossings[j]] - fDists[k][i]); //remember that fDists[k][i] is a negative value

+								ptPlaneIntersections[iPlaneIntersectionsCount] = (ptEndPoints[k][iAxisCrossings[j]] * (-fDists[k][i] * fInvTotalDist)) + (ptEndPoints[k][i] * (fDists[k][iAxisCrossings[j]] * fInvTotalDist));

+

+								Assert( fabs( ptPlaneIntersections[iPlaneIntersectionsCount].Dot( vQuadNormal ) - fQuadPlaneDist ) < 0.1f ); //intersection point is on plane

+

+								++iPlaneIntersectionsCount;

+							}

+						}

+					}

+				}

+			}

+		}		

+

+		if( ray.m_IsSwept )

+		{

+			for( int i = 0; i != 8; ++i )

+			{

+				if( iSides[0][i] != iSides[1][i] )

+				{

+					int iPosSide, iNegSide;

+					if( iSides[0][i] == 1 )

+					{

+						iPosSide = 0;

+						iNegSide = 1;

+					}

+					else

+					{

+						iPosSide = 1;

+						iNegSide = 0;

+					}

+

+					Assert( (fDists[iPosSide][i] >= 0.0f) && (fDists[iNegSide][i] <= 0.0f) );

+

+					float fInvTotalDist = 1.0f / (fDists[iPosSide][i] - fDists[iNegSide][i]); //remember that fDists[iNegSide][i] is a negative value

+					ptPlaneIntersections[iPlaneIntersectionsCount] = (ptEndPoints[iPosSide][i] * (-fDists[iNegSide][i] * fInvTotalDist)) + (ptEndPoints[iNegSide][i] * (fDists[iPosSide][i] * fInvTotalDist));

+

+					Assert( fabs( ptPlaneIntersections[iPlaneIntersectionsCount].Dot( vQuadNormal ) - fQuadPlaneDist ) < 0.1f ); //intersection point is on plane

+

+					++iPlaneIntersectionsCount;

+				}

+			}

+		}

+	}

+

+	//down here, we should simply have a collection of plane intersections, now we see if they reside within the quad

+	Assert( iPlaneIntersectionsCount != 0 );

+

+	for( int i = 0; i != iPlaneIntersectionsCount; ++i )

+	{

+		//these points are guaranteed to be on the plane, now just check to see if they're within the quad's extents

+		Vector vToPointFromQuadCenter = ptPlaneIntersections[i] - ptQuadCenter;

+

+		float fExt1Dist = vQuadExtent1_Normalized.Dot( vToPointFromQuadCenter );

+		if( fabs( fExt1Dist ) > fQuadExtent1Length )

+			return false; //point is outside boundaries

+

+		//vToPointFromQuadCenter -= vQuadExtent1_Normalized * fExt1Dist; //to handle diamond shaped quads

+

+		float fExt2Dist = vQuadExtent2_Normalized.Dot( vToPointFromQuadCenter );

+		if( fabs( fExt2Dist ) > fQuadExtent2Length )

+			return false; //point is outside boundaries

+	}

+

+	return true; //there were lines crossing the quad plane, and every line crossing that plane had its intersection with the plane within the quad's boundaries

+}

+

+#endif // !_STATIC_LINKED || _SHARED_LIB