#pragma once

#ifndef TCUBICBEZIER_INCLUDED

#define TCUBICBEZIER_INCLUDED

//-----------------------------------------------------------------------------

#include "tmathutil.h"

//#include "tcommon.h"

#include "tgeometry.h"

//#include <algorithm></algorithm>

using TConsts::epsilon;

#undef DVAPI

#undef DVVAR

#ifdef TPARAM_EXPORTS

#define DVAPI DV_EXPORT_API

#define DVVAR DV_EXPORT_VAR

#else

#define DVAPI DV_IMPORT_API

#define DVVAR DV_IMPORT_VAR

#endif

//-----------------------------------------------------------------------------

/*!

  Find the value of the parameter u0 of the cubic Bezier curve C(u)

  for a specified value x, with C(u0) = (x,y).

  \par x the x-component of a point on the Bezier curve

  \par a first control point of the Bezier curve

  \par aSpeed the tangent vector in a (that is the first control point minus the

  second)

  \par b the third control point

  \par bSpeed the tangent vector in b (that is the third control point minus the

  fourth)

  \ret the parameter value u0 of the Bezier curve C(u) for x, that is C(u0) =

  (x,y)

*/

DVAPI double invCubicBezierX(double x, const TPointD &a, const TPointD &aSpeed,

                             const TPointD &bSpeed, const TPointD &b);

//-----------------------------------------------------------------------------

/*!

  for C(u) a cubic Bezier curve, C(u0) = (x,y), find y from x.

  \par x the x-component of a point on the Bezier curve

  \par a first control point of the Bezier curve

  \par aSpeed the tangent vector in a (that is the first control point minus the

  second)

  \par b the third control point

  \par bSpeed the tangent vector in b (that is the third control point minus the

  fourth)

  \ret the y-component of a point P(x,y) on the Bezier curve, with C(u0) = P

*/

DVAPI double getCubicBezierY(double x, const TPointD &a, const TPointD &aSpeed,

                             const TPointD &bSpeed, const TPointD &b);

//-----------------------------------------------------------------------------

/*!

  for C(u)=(x,y) a cubic Bezier curve, find minimum and maximum y-values of C(u)

  \par a first control point of the Bezier curve

  \par aSpeed the tangent vector in a (that is the first control point minus the

  second)

  \par b the third control point

  \par bSpeed the tangent vector in b (that is the third control point minus the

  fourth)

  \ret a pair of points which are the minimum and maximum of the cubic Bezier

*/

DVAPI std::pair<tpointd, tpointd=""> getMinMaxCubicBezierY(const TPointD &a,</tpointd,>

                                                        const TPointD &aSpeed,

                                                        const TPointD &bSpeed,

                                                        const TPointD &b);

//-----------------------------------------------------------------------------

#endif  // TCUBICBEZIER_INCLUDED

//-----------------------------------------------------------------------------