celeritas::BoundingBox< T > Class Template Reference

Axis-aligned bounding box. More...

#include <BoundingBox.hh>

Public Types
Type aliases
using	real_type = T
using	Real3 = Array< real_type, 3 >

Public Member Functions
constexpr	BoundingBox ()
	Create a null bounding box.
	BoundingBox (Real3 const &lower, Real3 const &upper)
	Create a non-null bounding box from two points.
constexpr Real3 const &	lower () const
	Lower bbox coordinate.
constexpr Real3 const &	upper () const
	Upper bbox coordinate.
constexpr Real3 const &	point (Bound b) const
	Access a bounding point.
constexpr	operator bool () const
	Whether the bbox is in a valid state.
constexpr void	shrink (Bound bnd, Axis axis, real_type position)
	Reduce (clip) the bounding box's extent along an axis.
constexpr void	grow (Bound bnd, Axis axis, real_type position)
	Increase (expand) the bounding box's extent along an axis.
constexpr void	grow (Axis axis, real_type position)
	Increase (expand) the bounding box's extent along an axis.

Static Public Member Functions
static BoundingBox	from_infinite ()
	Create a bounding box with infinite extents.
static constexpr BoundingBox	from_unchecked (Real3 const &lower, Real3 const &upper)
	Create a bounding box from unchecked lower/upper bounds.

Detailed Description

template<class T = ::celeritas::real_type>
class celeritas::BoundingBox< T >

Axis-aligned bounding box.

Bounding boxes "contain" all points inside and on their faces. See is_inside in BoundingBoxUtils.hh .

The default bounding box is "null", which has at least one lower coordinate greater than its upper coordinate: it evaluates to false . A null bounding box still has the ability to be unioned and intersected with other bounding boxes with the expected effect, but geometrical operations on it (center, surface area, volume) are prohibited.

A "degenerate" bounding box is one that is well-defined but has zero volume because at least one lower coordinate is equal to the corresponding upper coordinate. Any point on the surface of this bounding box is still "inside". It may have nonzero surface area but will have zero volume.

Constructor & Destructor Documentation

BoundingBox() [1/2]

template<class T >

constexpr celeritas::BoundingBox< T >::BoundingBox ( )

inlineconstexpr

Create a null bounding box.

This should naturally satisfy

calc_union(BBox{}, other) = other:

and

calc_intersection(BBox{}, other) = other;

BoundingBox() [2/2]

template<class T >

celeritas::BoundingBox< T >::BoundingBox ( Real3 const &  lo, Real3 const &  hi  )

inline

Create a non-null bounding box from two points.

The lower and upper points are allowed to be equal (an empty bounding box at a single point) but upper must not be less than lower.

Member Function Documentation

from_unchecked()

template<class T >

constexpr BoundingBox< T > celeritas::BoundingBox< T >::from_unchecked ( Real3 const &  lo, Real3 const &  hi  )

inlinestaticconstexpr

Create a bounding box from unchecked lower/upper bounds.

This should be used exclusively for utilities that understand the "null" implementation of the bounding box.

grow() [1/2]

template<class T >

constexpr void celeritas::BoundingBox< T >::grow ( Axis  axis, real_type  position  )

inlineconstexpr

Increase (expand) the bounding box's extent along an axis.

If the point is outside the box, the box is expanded so the given boundary is on that point. Otherwise no change is made.

grow() [2/2]

template<class T >

constexpr void celeritas::BoundingBox< T >::grow ( Bound  bnd, Axis  axis, real_type  position  )

inlineconstexpr

Increase (expand) the bounding box's extent along an axis.

If the point is outside the box, the box is expanded so the given boundary is on that point. Otherwise no change is made.

shrink()

template<class T >

constexpr void celeritas::BoundingBox< T >::shrink ( Bound  bnd, Axis  axis, real_type  position  )

inlineconstexpr

Reduce (clip) the bounding box's extent along an axis.

If the point is inside the box, the box is clipped so the given boundary is on that point. Otherwise no change is made.

---

The documentation for this class was generated from the following file:

• BoundingBox.hh