wmldistrct3rct3.cpp

3D Game Engine Design Source Code非常棒

// Magic Software, Inc.
// http://www.magic-software.com
// http://www.wild-magic.com
// Copyright (c) 2003.  All Rights Reserved
//
// The Wild Magic Library (WML) source code is supplied under the terms of
// the license agreement http://www.magic-software.com/License/WildMagic.pdf
// and may not be copied or disclosed except in accordance with the terms of
// that agreement.

#include "WmlDistLin3Rct3.h"
#include "WmlDistRct3Rct3.h"
using namespace Wml;

//----------------------------------------------------------------------------
template <class Real>
Real Wml::SqrDistance (const Rectangle3<Real>& rkRct0,
    const Rectangle3<Real>& rkRct1, Real* pfRct0P0, Real* pfRct0P1,
    Real* pfRct1P0, Real* pfRct1P1)
{
    Real fS, fT, fS0, fT0;  // rct0 parameters
    Real fU, fV, fU0, fV0;  // rct1 parameters
    Real fSqrDist, fSqrDist0;
    Segment3<Real> kSeg;

    // compare edges of rct0 against all of rct1
    kSeg.Origin() = rkRct0.Origin();
    kSeg.Direction() = rkRct0.Edge0();
    fSqrDist = SqrDistance(kSeg,rkRct1,&fS,&fU,&fV);
    fT = 0.0f;

    kSeg.Direction() = rkRct0.Edge1();
    fSqrDist0 = SqrDistance(kSeg,rkRct1,&fT0,&fU0,&fV0);
    fS0 = 0.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    kSeg.Origin() = rkRct0.Origin() + rkRct0.Edge0();
    fSqrDist0 = SqrDistance(kSeg,rkRct1,&fT0,&fU0,&fV0);
    fS0 = 1.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    kSeg.Origin() = rkRct0.Origin() + rkRct0.Edge1();
    kSeg.Direction() = rkRct0.Edge0();
    fSqrDist0 = SqrDistance(kSeg,rkRct1,&fS0,&fU0,&fV0);
    fT0 = 1.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    // compare edges of pgm1 against all of pgm0
    kSeg.Origin() = rkRct1.Origin();
    kSeg.Direction() = rkRct1.Edge0();
    fSqrDist0 = SqrDistance(kSeg,rkRct0,&fU0,&fS0,&fT0);
    fV0 = 0.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    kSeg.Direction() = rkRct1.Edge1();
    fSqrDist0 = SqrDistance(kSeg,rkRct0,&fV0,&fS0,&fT0);
    fU0 = 0.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    kSeg.Origin() = rkRct1.Origin() + rkRct1.Edge0();
    fSqrDist0 = SqrDistance(kSeg,rkRct0,&fV0,&fS0,&fT0);
    fU0 = 1.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    kSeg.Origin() = rkRct1.Origin() + rkRct1.Edge1();
    kSeg.Direction() = rkRct1.Edge0();
    fSqrDist0 = SqrDistance(kSeg,rkRct0,&fU0,&fS0,&fT0);
    fV0 = 1.0f;
    if ( fSqrDist0 < fSqrDist )
    {
        fSqrDist = fSqrDist0;
        fS = fS0;
        fT = fT0;
        fU = fU0;
        fV = fV0;
    }

    if ( pfRct0P0 )
        *pfRct0P0 = fS;

    if ( pfRct0P1 )
        *pfRct0P1 = fT;

    if ( pfRct1P0 )
        *pfRct1P0 = fU;

    if ( pfRct1P1 )
        *pfRct1P1 = fV;

    return fSqrDist;
}
//----------------------------------------------------------------------------
template <class Real>
Real Wml::Distance (const Rectangle3<Real>& rkRct0,
    const Rectangle3<Real>& rkRct1, Real* pfRct0P0, Real* pfRct0P1,
    Real* pfRct1P0, Real* pfRct1P1)
{
    return Math<Real>::Sqrt(SqrDistance(rkRct0,rkRct1,pfRct0P0,pfRct0P1,
        pfRct1P0,pfRct1P1));
}
//----------------------------------------------------------------------------

//----------------------------------------------------------------------------
// explicit instantiation
//----------------------------------------------------------------------------
namespace Wml
{
template WML_ITEM float SqrDistance<float> (const Rectangle3<float>&,
    const Rectangle3<float>&, float*, float*, float*, float*);
template WML_ITEM float Distance<float> (const Rectangle3<float>&,
    const Rectangle3<float>&, float*, float*, float*, float*);

template WML_ITEM double SqrDistance<double> (const Rectangle3<double>&,
    const Rectangle3<double>&, double*, double*, double*, double*);
template WML_ITEM double Distance<double> (const Rectangle3<double>&,
    const Rectangle3<double>&, double*, double*, double*, double*);
}
//----------------------------------------------------------------------------