wmlmultiplecurve2.h

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.

#ifndef WMLMULTIPLECURVE2_H
#define WMLMULTIPLECURVE2_H

#include "WmlCurve2.h"

namespace Wml
{

template <class Real>
class WML_ITEM MultipleCurve2 : public Curve2<Real>
{
public:
    // Construction and destruction for abstract base class.  MultipleCurve2
    // accepts responsibility for deleting the input array.
    MultipleCurve2 (int iSegments, Real* afTime);
    virtual ~MultipleCurve2 ();

    // member access
    int GetSegments () const;
    const Real* GetTimes () const;

    // length-from-time and time-from-length
    virtual Real GetLength (Real fT0, Real fT1) const;
    virtual Real GetTime (Real fLength, int iIterations = 32,
        Real fTolerance = (Real)1e-06) const;

    // support for subdivision
    virtual Real GetVariation (Real fT0, Real fT1,
        const Vector2<Real>* pkP0 = NULL,
        const Vector2<Real>* pkP1 = NULL) const;

protected:
    int m_iSegments;
    Real* m_afTime;

    // These quantities are allocated by GetLength when they are needed the
    // first time.  The allocations occur in InitializeLength (called by
    // GetLength), so this member function must be 'const'. In order to
    // allocate the arrays in a 'const' function, they must be declared as
    // 'mutable'.
    mutable Real* m_afLength;
    mutable Real* m_afAccumLength;

    void GetKeyInfo (Real fTime, int& riKey, Real& rfDt) const;

    void InitializeLength () const;
    virtual Real GetSpeedKey (int iKey, Real fTime) const = 0;
    virtual Real GetLengthKey (int iKey, Real fT0, Real fT1) const = 0;
    virtual Real GetVariationKey (int iKey, Real fT0, Real fT1,
        const Vector2<Real>& rkA, const Vector2<Real>& rkB) const = 0;

    static Real GetSpeedWithData (Real fTime, void* pvData);
};

}

#endif