/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkBox.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkBox
 * @brief   implicit function for a bounding box
 *
 * vtkBox computes the implicit function and/or gradient for a axis-aligned
 * bounding box. (The superclasses transform can be used to modify this
 * orientation.) Each side of the box is orthogonal to all other sides
 * meeting along shared edges and all faces are orthogonal to the x-y-z
 * coordinate axes.  (If you wish to orient this box differently, recall that
 * the superclass vtkImplicitFunction supports a transformation matrix.)
 * vtkBox is a concrete implementation of vtkImplicitFunction.
 *
 * @sa
 * vtkCubeSource vtkImplicitFunction vtkBoundingBox
 */

#ifndef vtkBox_h
#define vtkBox_h

#include "vtkCommonDataModelModule.h" // For export macro
#include "vtkImplicitFunction.h"
class vtkBoundingBox;

class VTKCOMMONDATAMODEL_EXPORT vtkBox : public vtkImplicitFunction
{
public:
  vtkTypeMacro(vtkBox, vtkImplicitFunction);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  /**
   * Construct box with center at (0,0,0) and each side of length 1.0.
   */
  static vtkBox* New();

  /**
   * Evaluate box defined by the two points (pMin,pMax).
   */
  using vtkImplicitFunction::EvaluateFunction;
  double EvaluateFunction(double x[3]) override;

  /**
   * Evaluate the gradient of the box.
   */
  void EvaluateGradient(double x[3], double n[3]) override;

  ///@{
  /**
   * Set / get the bounding box using various methods.
   */
  void SetXMin(double p[3]);
  void SetXMin(double x, double y, double z);
  void GetXMin(double p[3]);
  void GetXMin(double& x, double& y, double& z);
  ///@}

  void SetXMax(double p[3]);
  void SetXMax(double x, double y, double z);
  void GetXMax(double p[3]);
  void GetXMax(double& x, double& y, double& z);

  void SetBounds(double xMin, double xMax, double yMin, double yMax, double zMin, double zMax);
  void SetBounds(const double bounds[6]);
  void GetBounds(
    double& xMin, double& xMax, double& yMin, double& yMax, double& zMin, double& zMax);
  void GetBounds(double bounds[6]);
  double* GetBounds() VTK_SIZEHINT(6);

  /**
   * A special method that allows union set operation on bounding boxes.
   * Start with a SetBounds(). Subsequent AddBounds() methods are union set
   * operations on the original bounds. Retrieve the final bounds with a
   * GetBounds() method.
   */
  void AddBounds(const double bounds[6]);

  /**
   * Bounding box intersection with line modified from Graphics Gems Vol
   * I. The method returns a non-zero value if the bounding box is
   * hit. Origin[3] starts the ray, dir[3] is the vector components of the
   * ray in the x-y-z directions, coord[3] is the location of hit, and t is
   * the parametric coordinate along line. (Notes: the intersection ray
   * dir[3] is NOT normalized.  Valid intersections will only occur between
   * 0<=t<=1.)
   */
  static char IntersectBox(const double bounds[6], const double origin[3], const double dir[3],
    double coord[3], double& t, const double tolerance = 0.0);

  /**
   * Intersect a line with the box.  Give the endpoints of the line in
   * p1 and p2.  The parameteric distances from p1 to the entry and exit
   * points are returned in t1 and t2, where t1 and t2 are clamped to the
   * range [0,1].  The entry and exit planes are returned in plane1 and
   * plane2 where integers (0, 1, 2, 3, 4, 5) stand for the
   * (xmin, xmax, ymin, ymax, zmin, zmax) planes respectively, and a value
   * of -1 means that no intersection occurred.  The actual intersection
   * coordinates are stored in x1 and x2, which can be set to nullptr of you
   * do not need them to be returned.  The function return value will be
   * zero if the line is wholly outside of the box.
   */
  static int IntersectWithLine(const double bounds[6], const double p1[3], const double p2[3],
    double& t1, double& t2, double x1[3], double x2[3], int& plane1, int& plane2);

  /**
   * Same method as vtkBox::IntersectWithLine, except that t1 and t2 can be outside of [0,1].
   * t1 is the distance of x1 to p1 in parametric coordinates, and t2 is the distance of x2 to p1
   * in parametric coordinates as well.
   * In vtkBox::IntersectWithInLine, it is assumed that [p1,p2] is a segment, here, it is
   * assumed that it is a line with no ends.
   * t1 <= t2, which means that x1 is always "before" x2 on the line parameterized by [p1,p2].
   * x1 and x2 can be set to nullptr without crash.
   */
  static bool IntersectWithInfiniteLine(const double bounds[6], const double p1[3],
    const double p2[3], double& t1, double& t2, double x1[3], double x2[3], int& plane1,
    int& plane2);

  /**
   * Plane intersection with the box. The plane is infinite in extent and
   * defined by an origin and normal. The function indicates whether the
   * plane intersects, not the particulars of intersection points and such.
   * The function returns non-zero if the plane and box intersect; zero
   * otherwise.
   */
  static vtkTypeBool IntersectWithPlane(double bounds[6], double origin[3], double normal[3]);

  /**
   * Plane intersection with the box. The plane is infinite in extent and
   * defined by an origin and normal. The function returns the number of
   * intersection points, and if does, up to six ordered intersection points
   * are provided (i.e., the points are ordered and form a valid polygon).
   * Thus the function returns non-zero if the plane and box intersect; zero
   * otherwise. Note that if there is an intersection, the number of
   * intersections ranges from [3,6]. xout memory layout is consistent with
   * vtkPoints array layout and is organized as (xyz, xyz, xyz, xyz, xyz,
   * xyz).
   */
  static vtkTypeBool IntersectWithPlane(
    double bounds[6], double origin[3], double normal[3], double xout[18]);

  /**
   * Is a box in a frustum. Returns true if the box is in the frustum
   * even partially. The frustum is defined as 6 planes. This method
   * is not exact may and return true for cases where there is no
   * intersection. It should never return false when there is an
   * intersection though.
   */
  static vtkTypeBool IsBoxInFrustum(double planes[24], double bounds[6]);

protected:
  vtkBox();
  ~vtkBox() override;

  vtkBoundingBox* BBox;
  double Bounds[6]; // supports the GetBounds() method

private:
  vtkBox(const vtkBox&) = delete;
  void operator=(const vtkBox&) = delete;
};

inline void vtkBox::SetXMin(double p[3])
{
  this->SetXMin(p[0], p[1], p[2]);
}

inline void vtkBox::SetXMax(double p[3])
{
  this->SetXMax(p[0], p[1], p[2]);
}

#endif
