DragonNest/Client/EtCutSceneTool/IntersectUtil.cpp

#include "stdafx.h"
#include "EternityEngine.h"
#include "intersectUtil.h"

const float EPSILON = 0.000001f;



CIntersectUtil::CIntersectUtil(void)
{
}

CIntersectUtil::~CIntersectUtil(void)
{
}



// :*: <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD> :*:
// 1. <20>켱, <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><> <20><><EFBFBD>ʿ<EFBFBD> <20>ִ<EFBFBD><D6B4><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ؼ<EFBFBD> <20><><EFBFBD>ʿ<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 100% <20>浹 <20><><EFBFBD><EFBFBD><EFBFBD>̹Ƿ<CCB9> <20>״<EFBFBD><D7B4><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>Ѵ<EFBFBD>.
// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD>Ϳ<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20>߽<EFBFBD><DFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>, <20><>, <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>̷<EFBFBD><CCB7><EFBFBD>
// <20><><EFBFBD><EFBFBD> <20>а<EFBFBD><D0B0><EFBFBD> <20><><EFBFBD>̰<EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20>ܺ<EFBFBD><DCBA><EFBFBD> <20><><EFBFBD>찡 <20>ǰڴ<C7B0>.
//
// 2. <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20>߽ɱ<DFBD><C9B1><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD><C5B8><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20>߽ɱ<DFBD><C9B1><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD>а<EFBFBD>  <20><>Ÿ<EFBFBD><C5B8><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><>Ģ<EFBFBD><C4A2> <20><><EFBFBD><EFBFBD><EFBFBD>Ͽ<EFBFBD> 
// <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD><C5B8><EFBFBD> <20><><EFBFBD>Ѵ<EFBFBD>. <20><> <20>Ÿ<EFBFBD><C5B8><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> ũ<><C5A9> <20>浹<EFBFBD><E6B5B9><EFBFBD><EFBFBD>.
bool CIntersectUtil::RaySphereIntersect( const IN EtVector3& vRayStartPos, const IN EtVector3& vRayDir /* <20>ݵ<EFBFBD><DDB5><EFBFBD> <20><><EFBFBD><EFBFBD>ȭ <20><> <20><><EFBFBD><EFBFBD> */, 
                                         const IN float fRadius, const IN EtVector3& vSpherePos,
                                         OUT EtVector3* pvNearIntersectPos, OUT EtVector3* pvFarIntersectPos )
{
	EtVector3 vRayStartToCenter;
	float fDotResult = 0.0f;
	float fLengthSqA = 0.0f;              // <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20>߽ɱ<DFBD><C9B1><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD> <20><><EFBFBD><EFBFBD>
	float fLengthSqB = 0.0f;              // <20><><EFBFBD><EFBFBD> <20>߽ɿ<DFBD><C9BF><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD> <20><><EFBFBD><EFBFBD>
	float fLengthSqC = 0.0f;              // <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD> <20><><EFBFBD><EFBFBD>
	float fRadiusSq = fRadius * fRadius;

	vRayStartToCenter = vSpherePos - vRayStartPos;
	fDotResult = EtVec3Dot( &vRayDir, &vRayStartToCenter );

	fLengthSqA = EtVec3LengthSq( &vRayStartToCenter );

	if( fDotResult < 0.0f && fLengthSqA > fRadiusSq )
		return false;

	fLengthSqC = fDotResult * fDotResult;
	fLengthSqB = fLengthSqA - fLengthSqC;

	if( fRadiusSq < fLengthSqB )
		return false;

	if( NULL != pvNearIntersectPos || NULL != pvFarIntersectPos )
	{
		fLengthSqC = fRadiusSq - fLengthSqB;
	    
		if( pvNearIntersectPos )
			*pvNearIntersectPos = vRayStartPos + (fDotResult - sqrt(fLengthSqC)) * vRayDir;
	    
		if( pvFarIntersectPos )
			*pvFarIntersectPos = vRayStartPos + (fDotResult + sqrt(fLengthSqC)) * vRayDir;
	}

	return true;
}



// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>




//int RayTriIntersect(CVector  orig, CVector dir,CVector  vert0, CVector vert1, CVector vert2,
//					Scalar *t, Scalar *u, Scalar *v)
//{
//	CVector edge1, edge2, tvec, pvec, qvec;
//	Scalar det,inv_det;
//
//	/* find vectors for two edges sharing vert0 */
//	SUB(edge1, vert1, vert0);
//	SUB(edge2, vert2, vert0);
//
//	/* begin calculating determinant - also used to calculate U parameter */
//	CROSS(pvec, dir, edge2);
//
//	/* if determinant is near zero, ray lies in plane of triangle */
//	det = DOT(edge1, pvec);
//
//#ifdef TEST_CULL           /* define TEST_CULL if culling is desired */
//	if (det < EPSILON)
//		return 0;
//
//	/* calculate distance from vert0 to ray origin */
//	SUB(tvec, orig, vert0);
//
//	/* calculate U parameter and test bounds */
//	*u = DOT(tvec, pvec);
//	if (*u < 0.0 || *u > det)
//		return 0;
//
//	/* prepare to test V parameter */
//	CROSS(qvec, tvec, edge1);
//
//	/* calculate V parameter and test bounds */
//	*v = DOT(dir, qvec);
//	if (*v < 0.0 || *u + *v > det)
//		return 0;
//
//	/* calculate t, scale parameters, ray intersects triangle */
//	*t = DOT(edge2, qvec);
//	inv_det = 1.0 / det;
//	*t *= inv_det;
//	*u *= inv_det;
//	*v *= inv_det;
//#else                    /* the non-culling branch */
//	if (det > -EPSILON && det < EPSILON)
//		return 0;
//	inv_det = 1.0 / det;
//
//	/* calculate distance from vert0 to ray origin */
//	SUB(tvec, orig, vert0);
//
//	/* calculate U parameter and test bounds */
//	*u = DOT(tvec, pvec) * inv_det;
//	if (*u < 0.0 || *u > 1.0)
//		return 0;
//
//	/* prepare to test V parameter */
//	CROSS(qvec, tvec, edge1);
//
//	/* calculate V parameter and test bounds */
//	*v = DOT(dir, qvec) * inv_det;
//	if (*v < 0.0 || *u + *v > 1.0)
//		return 0;
//
//	/* calculate t, ray intersects triangle */
//	*t = DOT(edge2, qvec) * inv_det;
//#endif
//	return 1;



// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
bool CIntersectUtil::RayTriIntersect( const IN EtVector3& vRayStart, const IN EtVector3& vRayDir, /* <20><><EFBFBD><EFBFBD>ȭ<EFBFBD><C8AD> <20><><EFBFBD><EFBFBD> */
									  const IN EtVector3 vVert0, const IN EtVector3 vVert1, const IN EtVector3 vVert2,
									  float *t, float *u, float *v )
{
	EtVector3 vEdge[ 2 ];
	EtVector3 vTvec, vPvec, vQvec;
	float fDet = 0.0f;
	float fInv_det = 0.0f;

	// vVert0 <20><> <20><><EFBFBD><EFBFBD><EFBFBD>ϴ<EFBFBD> <20><> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD>Ѵ<EFBFBD>.
	vEdge[ 0 ] = vVert1 - vVert0;
	vEdge[ 1 ] = vVert2 - vVert0;

	// <20><><EFBFBD>Ľ<EFBFBD><C4BD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ϱ<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>Ѵ<EFBFBD>. <20><> <20><><EFBFBD><EFBFBD> U <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD>δ<EFBFBD>.
	EtVec3Cross( &vPvec, &vRayDir, &vEdge[ 1 ] );

	// <20><><EFBFBD>Ľ<EFBFBD><C4BD><EFBFBD> <20><><EFBFBD>ο<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> Ray<61><79> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ϴٴ<CFB4> <20><><EFBFBD><EFBFBD>~!! <20>׷<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>浹<EFBFBD><E6B5B9> <20>Ͼ <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>.
	fDet = EtVec3Dot( &vEdge[ 0 ], &vPvec );

#ifdef TEST_CULL			// <20>ĸ<EFBFBD> <20>ø<EFBFBD><C3B8><EFBFBD> <20><> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>?
	if( det < EPSILON )
		return false;

	// vVert0 <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD>
	vTvec = vRayStart - vVert0;

	// U <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ϰ<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ȿ<EFBFBD> <20>ִ<EFBFBD><D6B4><EFBFBD> üũ<C3BC>Ѵ<EFBFBD>.
	*u = EtVec3Dot( &vTvec, &vPvec );
	if( *u < 0.0f || *u > fDet )
		return false;

	// V <20><> <20>׽<EFBFBD>Ʈ<EFBFBD><C6AE> <20><><EFBFBD><EFBFBD> <20>غ<EFBFBD>
	EtVec3Cross( &vQvec, &vTvec, &vEdge[ 0 ] );

	// V <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ȿ<EFBFBD> <20>ִ<EFBFBD><D6B4><EFBFBD> üũ<C3BC>Ѵ<EFBFBD>.
	*v = EtVec3Dot( &vRayDir, &vQvec );
	if( *v < 0.0f || *u + *v > det )
		return false;

	// T <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>ϰ<EFBFBD> Ȯ<><C8AE> <20>Ķ<EFBFBD><C4B6><EFBFBD><EFBFBD>͸<EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ش<EFBFBD>.
	*t = EtVec3Dot( &vRayDir, &vQvec );
	fInv_det = 1.0f / fDet;
	*t *= fInv_det;
	*u *= fInv_det;
	*v *= fInv_det;
#else				 // <20>ø<EFBFBD><C3B8><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>.
	if( fDet > -EPSILON && fDet < EPSILON )
		return false;

	fInv_det = 1.0f / fDet;
	
	// vVert0 <20><><EFBFBD><EFBFBD> RayStart <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>Ÿ<EFBFBD>
	vTvec = vRayStart - vVert0;

	// U <20><> <20><><EFBFBD><EFBFBD>
	*u = EtVec3Dot( &vTvec, &vPvec ) * fInv_det;
	if( *u < 0.0f || *u > 1.0f )
		return false;

	// V <20><> <20><><EFBFBD><EFBFBD>
	EtVec3Cross( &vQvec, &vTvec, &vEdge[ 0 ] );

	*v = EtVec3Dot( &vRayDir, &vQvec ) * fInv_det;
	if( *v < 0.0f || *u + *v > 1.0f )
		return 0;

	*t = EtVec3Dot( &vEdge[ 1 ], &vQvec ) * fInv_det;
#endif

	return true;
}