// Created on: 1991-01-28
// Created by: Remi Lequette
// Copyright (c) 1991-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#ifndef _Bnd_Box_HeaderFile
#define _Bnd_Box_HeaderFile

#include <Standard.hxx>
#include <Standard_DefineAlloc.hxx>
#include <Standard_Handle.hxx>

#include <Standard_Real.hxx>
#include <Standard_Integer.hxx>
#include <Standard_Boolean.hxx>
class Standard_ConstructionError;
class gp_Pnt;
class gp_Dir;
class gp_Trsf;
class gp_Lin;
class gp_Pln;


//! Describes a bounding box in 3D space.
//! A bounding box is parallel to the axes of the coordinates
//! system. If it is finite, it is defined by the three intervals:
//! -   [ Xmin,Xmax ],
//! -   [ Ymin,Ymax ],
//! -   [ Zmin,Zmax ].
//! A bounding box may be infinite (i.e. open) in one or more
//! directions. It is said to be:
//! -   OpenXmin if it is infinite on the negative side of the   "X Direction";
//! -   OpenXmax if it is infinite on the positive side of the "X Direction";
//! -   OpenYmin if it is infinite on the negative side of the   "Y Direction";
//! -   OpenYmax if it is infinite on the positive side of the "Y Direction";
//! -   OpenZmin if it is infinite on the negative side of the   "Z Direction";
//! -   OpenZmax if it is infinite on the positive side of the "Z Direction";
//! -   WholeSpace if it is infinite in all six directions. In this
//! case, any point of the space is inside the box;
//! -   Void if it is empty. In this case, there is no point included in the box.
//! A bounding box is defined by:
//! -   six bounds (Xmin, Xmax, Ymin, Ymax, Zmin and
//! Zmax) which limit the bounding box if it is finite,
//! -   eight flags (OpenXmin, OpenXmax, OpenYmin,
//! OpenYmax, OpenZmin, OpenZmax,
//! WholeSpace and Void) which describe the
//! bounding box if it is infinite or empty, and
//! -   a gap, which is included on both sides in any direction
//! when consulting the finite bounds of the box.
class Bnd_Box 
{
public:

  DEFINE_STANDARD_ALLOC

  
  //! Creates an empty Box.
  //! The constructed box is qualified Void. Its gap is null.
  Standard_EXPORT Bnd_Box();

  //! Sets this bounding box so that it  covers the whole of 3D space.
  //! It is infinitely  long in all directions.
  void SetWhole() { Flags = WholeMask; }

  //! Sets this bounding box so that it is empty. All points are outside a void box.
  void SetVoid()
  {
    Flags = VoidMask;
    Gap   = 0.0;
  }

  //! Sets this bounding box so that it bounds
  //! -   the point P. This involves first setting this bounding box
  //! to be void and then adding the point P.
  Standard_EXPORT void Set (const gp_Pnt& P);
  
  //! Sets this bounding box so that it bounds
  //! the half-line defined by point P and direction D, i.e. all
  //! points M defined by M=P+u*D, where u is greater than
  //! or equal to 0, are inside the bounding volume. This
  //! involves first setting this box to be void and then adding   the half-line.
  Standard_EXPORT void Set (const gp_Pnt& P, const gp_Dir& D);
  
  //! Enlarges this bounding box, if required, so that it
  //! contains at least:
  //! -   interval [ aXmin,aXmax ] in the "X Direction",
  //! -   interval [ aYmin,aYmax ] in the "Y Direction",
  //! -   interval [ aZmin,aZmax ] in the "Z Direction";
  Standard_EXPORT void Update (const Standard_Real aXmin, const Standard_Real aYmin, const Standard_Real aZmin, const Standard_Real aXmax, const Standard_Real aYmax, const Standard_Real aZmax);
  
  //! Adds a point of coordinates (X,Y,Z) to this bounding box.
  Standard_EXPORT void Update (const Standard_Real X, const Standard_Real Y, const Standard_Real Z);
  
  //! Returns the gap of this bounding box.
  Standard_EXPORT Standard_Real GetGap() const;
  
  //! Set the gap of this bounding box to abs(Tol).
  Standard_EXPORT void SetGap (const Standard_Real Tol);
  
  //! Enlarges the      box    with    a   tolerance   value.
  //! (minvalues-Abs(<tol>) and maxvalues+Abs(<tol>))
  //! This means that the minimum values of its X, Y and Z
  //! intervals of definition, when they are finite, are reduced by
  //! the absolute value of Tol, while the maximum values are
  //! increased by the same amount.
  Standard_EXPORT void Enlarge (const Standard_Real Tol);
  
  //! Returns the bounds of this bounding box. The gap is included.
  //! If this bounding box is infinite (i.e. "open"), returned values
  //! may be equal to +/- Precision::Infinite().
  //! Standard_ConstructionError exception will be thrown if the box is void.
  //! if IsVoid()
  Standard_EXPORT void Get (Standard_Real& theXmin, Standard_Real& theYmin, Standard_Real& theZmin, Standard_Real& theXmax, Standard_Real& theYmax, Standard_Real& theZmax) const;
  
  //! Returns the lower corner of this bounding box. The gap is included.
  //! If this bounding box is infinite (i.e. "open"), returned values
  //! may be equal to +/- Precision::Infinite().
  //! Standard_ConstructionError exception will be thrown if the box is void.
  //! if IsVoid()
  Standard_EXPORT gp_Pnt CornerMin() const;
  
  //! Returns the upper corner of this bounding box. The gap is included.
  //! If this bounding box is infinite (i.e. "open"), returned values
  //! may be equal to +/- Precision::Infinite().
  //! Standard_ConstructionError exception will be thrown if the box is void.
  //! if IsVoid()
  Standard_EXPORT gp_Pnt CornerMax() const;

  //! The   Box will be   infinitely   long  in the Xmin
  //! direction.
  void OpenXmin() { Flags |= XminMask; }

  //! The   Box will be   infinitely   long  in the Xmax
  //! direction.
  void OpenXmax() { Flags |= XmaxMask; }

  //! The   Box will be   infinitely   long  in the Ymin
  //! direction.
  void OpenYmin() { Flags |= YminMask; }

  //! The   Box will be   infinitely   long  in the Ymax
  //! direction.
  void OpenYmax() { Flags |= YmaxMask; }

  //! The   Box will be   infinitely   long  in the Zmin
  //! direction.
  void OpenZmin() { Flags |= ZminMask; }

  //! The   Box will be   infinitely   long  in the Zmax
  //! direction.
  void OpenZmax() { Flags |= ZmaxMask; }

  //! Returns true if this bounding box is open in the  Xmin direction.
  Standard_Boolean IsOpenXmin() const { return (Flags & XminMask) != 0; }

  //! Returns true if this bounding box is open in the  Xmax direction.
  Standard_Boolean IsOpenXmax() const { return (Flags & XmaxMask) != 0; }

  //! Returns true if this bounding box is open in the  Ymix direction.
  Standard_Boolean IsOpenYmin() const { return (Flags & YminMask) != 0; }

  //! Returns true if this bounding box is open in the  Ymax direction.
  Standard_Boolean IsOpenYmax() const { return (Flags & YmaxMask) != 0; }

  //! Returns true if this bounding box is open in the  Zmin direction.
  Standard_Boolean IsOpenZmin() const { return (Flags & ZminMask) != 0; }

  //! Returns true if this bounding box is open in the  Zmax  direction.
  Standard_Boolean IsOpenZmax() const { return (Flags & ZmaxMask) != 0; }

  //! Returns true if this bounding box is infinite in all 6 directions (WholeSpace flag).
  Standard_Boolean IsWhole()    const { return (Flags & WholeMask) == WholeMask; }

  //! Returns true if this bounding box is empty (Void flag).
  Standard_Boolean IsVoid()     const { return (Flags & VoidMask) != 0; }

  //! true if xmax-xmin < tol.
  Standard_EXPORT Standard_Boolean IsXThin (const Standard_Real tol) const;
  
  //! true if ymax-ymin < tol.
  Standard_EXPORT Standard_Boolean IsYThin (const Standard_Real tol) const;
  
  //! true if zmax-zmin < tol.
  Standard_EXPORT Standard_Boolean IsZThin (const Standard_Real tol) const;
  
  //! Returns true if IsXThin, IsYThin and IsZThin are all true,
  //! i.e. if the box is thin in all three dimensions.
  Standard_EXPORT Standard_Boolean IsThin (const Standard_Real tol) const;
  
  //! Returns a bounding box which is the result of applying the
  //! transformation T to this bounding box.
  //! Warning
  //! Applying a geometric transformation (for example, a
  //! rotation) to a bounding box generally increases its
  //! dimensions. This is not optimal for algorithms which use it.
  Standard_EXPORT Bnd_Box Transformed (const gp_Trsf& T) const;
  
  //! Adds the box <Other> to <me>.
  Standard_EXPORT void Add (const Bnd_Box& Other);
  
  //! Adds a Pnt to the box.
  Standard_EXPORT void Add (const gp_Pnt& P);
  
  //! Extends  <me> from the Pnt <P> in the direction <D>.
  Standard_EXPORT void Add (const gp_Pnt& P, const gp_Dir& D);
  
  //! Extends the Box  in the given Direction, i.e. adds
  //! an  half-line. The   box  may become   infinite in
  //! 1,2 or 3 directions.
  Standard_EXPORT void Add (const gp_Dir& D);
  
  //! Returns True if the Pnt is out the box.
  Standard_EXPORT Standard_Boolean IsOut (const gp_Pnt& P) const;
  
  //! Returns False if the line intersects the box.
  Standard_EXPORT Standard_Boolean IsOut (const gp_Lin& L) const;
  
  //! Returns False if the plane intersects the box.
  Standard_EXPORT Standard_Boolean IsOut (const gp_Pln& P) const;
  
  //! Returns False if the <Box> intersects or is inside <me>.
  Standard_EXPORT Standard_Boolean IsOut (const Bnd_Box& Other) const;
  
  //! Returns False if  the transformed <Box> intersects
  //! or  is inside <me>.
  Standard_EXPORT Standard_Boolean IsOut (const Bnd_Box& Other, const gp_Trsf& T) const;
  
  //! Returns False  if the transformed <Box> intersects
  //! or  is inside the transformed box <me>.
  Standard_EXPORT Standard_Boolean IsOut (const gp_Trsf& T1, const Bnd_Box& Other, const gp_Trsf& T2) const;
  
  //! Returns False  if the flat band lying between two parallel
  //! lines represented by their reference points <P1>, <P2> and
  //! direction <D> intersects the box.
  Standard_EXPORT Standard_Boolean IsOut (const gp_Pnt& P1, const gp_Pnt& P2, const gp_Dir& D) const;
  
  //! Computes the minimum distance between two boxes.
  Standard_EXPORT Standard_Real Distance (const Bnd_Box& Other) const;
  
  Standard_EXPORT void Dump() const;

  //! Computes the squared diagonal of me.
  Standard_Real SquareExtent() const
  {
    if (IsVoid())
    {
      return 0.0;
    }

    const Standard_Real aDx = Xmax - Xmin + Gap + Gap;
    const Standard_Real aDy = Ymax - Ymin + Gap + Gap;
    const Standard_Real aDz = Zmax - Zmin + Gap + Gap;
    return aDx * aDx + aDy * aDy + aDz * aDz;
  }

protected:

  //! Bit flags.
  enum MaskFlags
  {
    VoidMask  = 0x01,
    XminMask  = 0x02,
    XmaxMask  = 0x04,
    YminMask  = 0x08,
    YmaxMask  = 0x10,
    ZminMask  = 0x20,
    ZmaxMask  = 0x40,
    WholeMask = 0x7e
  };

private:

  Standard_Real Xmin;
  Standard_Real Xmax;
  Standard_Real Ymin;
  Standard_Real Ymax;
  Standard_Real Zmin;
  Standard_Real Zmax;
  Standard_Real Gap;
  Standard_Integer Flags;

};

#endif // _Bnd_Box_HeaderFile
