AxisAlignedBoundingBox Class Reference

#include <math.h>

Class Description

Represents a bounding box whose axes are aligned with the coordinate system.

The box is usually referred by two corners, the start corner means the one whose coordinates are the smallest, while the end corner means the opposite.

Examples:

Definition at line 838 of file math.h.

Public Member Functions
	AxisAlignedBoundingBox (void)
	Creates an empty bounding box. More...
	AxisAlignedBoundingBox (const Vector &vStart, const Vector &vEnd)
	Creates an object by specifying two corners of the box. More...
	AxisAlignedBoundingBox (const Vector &vCenter, float fSize)
	Creates an object by specifying the center of it and the distance of the sides from the center. More...
	AxisAlignedBoundingBox (const AxisAlignedBoundingBox &cA)
	Creates an object by cloning another one. More...
AxisAlignedBoundingBox &	operator= (const AxisAlignedBoundingBox &cBB)
	Assigns the value of a box object to another one. More...
AxisAlignedBoundingBox &	operator+= (const AxisAlignedBoundingBox &cBB)
	Extends the box to contain another one. More...
bool	operator== (const AxisAlignedBoundingBox &cBB) const
	Returns true if two boxes are identical, false otherwise. More...
void	Reset (void)
	Makes the box empty. More...
void	Serialize (Stream &s)
	Writes/reads the object data to/from a stream. More...
bool	operator!= (const AxisAlignedBoundingBox &cBox) const
	returns true if the two boxes are different, false otherwise. More...
void	Extend (const Vector &cV) throw ()
	Extends the box to contain the passed point. More...
void	Extend (const AxisAlignedBoundingBox &bb)
	Extends the box to contain another one. More...
void	ExpandBy (float f) throw ()
	Expands the AABB by a specified amount in all directions. More...
void	Transform (const class Matrix &mMatrix)
	Transforms the box with the passed-in matrix, and returns the smallest box which contains the result. More...
Vector	operator[] (int iCornerIndex) const
	Returns the corners of the box. Valid indexes are 0-7. More...
float	Size (void) const
	Returns the maximum edge length of the box. More...
float	XSize (void) const
	Returns the length of the box along the X axis. More...
float	YSize (void) const
	Returns the length of the box along the Y axis. More...
float	ZSize (void) const
	Returns the length of the box along the Y axis. More...
float	Volume (void) const
	Returns the volume of the box. More...
Vector	Center (void) const
	Returns the center of the box. More...
bool	IsPartOf (const AxisAlignedBoundingBox &cBB) const
	Returns true if the passed-in box contains this box. More...
bool	IsTouching (const AxisAlignedBoundingBox &cBB) const
	Returns true if the two boxes intersect at all. More...
bool	IsTouching (const Vector &vStart, const Vector &vEnd, float &fPlace) const
	Returns true if the box intersects any part of a specified line. More...
bool	IsContaining (const Vector &cV) const
	Returns true if the box contains the specified point. More...
bool	IsContaining (const AxisAlignedBoundingBox &b) const
	Returns true if the box contains the specified box. More...
AxisAlignedBoundingBox	Intersection (const AxisAlignedBoundingBox &cOther) const
	Returns the intersection between this box and cOther. More...
bool	IsEmpty (void) const
	Returns true if the box is empy. More...
AxisAlignedBoundingBox	operator* (float fFactor)
	Multiplies the box coordinates with a scalar value. More...

Static Public Member Functions
static AxisAlignedBoundingBox	SphereBoundingBox (const Vector &cCenter, float fRadius, const Matrix &mTransform)
	Returns the bounding box of the given sphere, in the given coordinate space. More...

Public Attributes
Vector	m_vStart
Vector	m_vEnd

Constructor & Destructor Documentation

AxisAlignedBoundingBox ( void  )

inline

Creates an empty bounding box.

Definition at line 842 of file math.h.

{ Reset(); };

AxisAlignedBoundingBox ( const Vector &  vStart, const Vector &  vEnd  )

inline

Creates an object by specifying two corners of the box.

Definition at line 845 of file math.h.

                                                                       :
        m_vStart( vStart ),
        m_vEnd( vEnd ) {};

AxisAlignedBoundingBox ( const Vector &  vCenter, float  fSize  )

inline

Creates an object by specifying the center of it and the distance of the sides from the center.

This will be a cube.

Definition at line 851 of file math.h.

    {
        Vector v( fSize, fSize, fSize );
        m_vStart = vCenter-v;
        m_vEnd   = vCenter+v;
    };

AxisAlignedBoundingBox ( const AxisAlignedBoundingBox &  cA )

inline

Creates an object by cloning another one.

Definition at line 859 of file math.h.

                                                               :
    m_vStart( cA.m_vStart ),
    m_vEnd( cA.m_vEnd ) {};

Member Function Documentation

AxisAlignedBoundingBox& operator= ( const AxisAlignedBoundingBox &  cBB )

inline

Assigns the value of a box object to another one.

Definition at line 864 of file math.h.

    {
        m_vStart = cBB.m_vStart;
        m_vEnd = cBB.m_vEnd;
        return *this;
    };

AxisAlignedBoundingBox& operator+= ( const AxisAlignedBoundingBox &  cBB )

inline

Extends the box to contain another one.

Definition at line 872 of file math.h.

    {
        for ( int i = 0; i < 8; i++ ) Extend( cBB[i] );
        return *this;
    };

bool operator== ( const AxisAlignedBoundingBox &  cBB ) const

inline

Returns true if two boxes are identical, false otherwise.

Definition at line 879 of file math.h.

    {
        return m_vStart == cBB.m_vStart && m_vEnd == cBB.m_vEnd;
    };

void Reset ( void  )

inline

Makes the box empty.

Definition at line 885 of file math.h.

    {
        m_vStart.Set( 0, 0, 0 );
        m_vEnd.Set( -1, -1, -1 );
    };

void Serialize

(

Stream &

s

)

Writes/reads the object data to/from a stream.

bool operator!= ( const AxisAlignedBoundingBox &  cBox ) const

inline

returns true if the two boxes are different, false otherwise.

Definition at line 896 of file math.h.

        { return !(operator ==(cBox)); };

void Extend ( const Vector &  cV ) throw ( )

inline

Extends the box to contain the passed point.

Definition at line 901 of file math.h.

    {
        if ( IsEmpty() ) {
            m_vStart = m_vEnd = cV;
        } else {
            if ( m_vStart.m_fX > cV.m_fX ) m_vStart.m_fX = cV.m_fX;
            if ( m_vStart.m_fY > cV.m_fY ) m_vStart.m_fY = cV.m_fY;
            if ( m_vStart.m_fZ > cV.m_fZ ) m_vStart.m_fZ = cV.m_fZ;
            if ( m_vEnd.m_fX   < cV.m_fX ) m_vEnd.m_fX   = cV.m_fX;
            if ( m_vEnd.m_fY   < cV.m_fY ) m_vEnd.m_fY   = cV.m_fY;
            if ( m_vEnd.m_fZ   < cV.m_fZ ) m_vEnd.m_fZ   = cV.m_fZ;
        }
    }

void Extend ( const AxisAlignedBoundingBox &  bb )

inline

Extends the box to contain another one.

Definition at line 916 of file math.h.

    {
        if ( !bb.IsEmpty() ) {
            Extend( bb.m_vStart );
            Extend( bb.m_vEnd );
        };
    };

void ExpandBy ( float  f ) throw ( )

inline

Expands the AABB by a specified amount in all directions.

A negative value will shrink the box by that amount.

Definition at line 926 of file math.h.

    {
        m_vStart -= f;
        m_vEnd   += f;
    }

void Transform

(

const class Matrix &

mMatrix

)

Transforms the box with the passed-in matrix, and returns the smallest box which contains the result.

This is usually larger than the original box, because the transformation might rotate the box out of axis alignment.

Vector operator[]

(

int

iCornerIndex

)

const

Returns the corners of the box. Valid indexes are 0-7.

float Size ( void  ) const

inline

Returns the maximum edge length of the box.

Definition at line 942 of file math.h.

{ return Max( Max( XSize(), YSize() ), ZSize() ); };

float XSize ( void  ) const

inline

Returns the length of the box along the X axis.

Definition at line 945 of file math.h.

{ return m_vEnd.m_fX-m_vStart.m_fX; };

float YSize ( void  ) const

inline

Returns the length of the box along the Y axis.

Definition at line 948 of file math.h.

{ return m_vEnd.m_fY-m_vStart.m_fY; };

float ZSize ( void  ) const

inline

Returns the length of the box along the Y axis.

Definition at line 951 of file math.h.

{ return m_vEnd.m_fZ-m_vStart.m_fZ; };

float Volume ( void  ) const

inline

Returns the volume of the box.

Definition at line 954 of file math.h.

{ return XSize()*YSize()*ZSize(); };

Vector Center ( void  ) const

inline

Returns the center of the box.

Definition at line 957 of file math.h.

{ return (m_vStart+m_vEnd)*0.5f; };

bool IsPartOf ( const AxisAlignedBoundingBox &  cBB ) const

inline

Returns true if the passed-in box contains this box.

Definition at line 960 of file math.h.

    {
        return (
            m_vStart.m_fX >= cBB.m_vStart.m_fX && m_vEnd.m_fX <= cBB.m_vEnd.m_fX &&
            m_vStart.m_fY >= cBB.m_vStart.m_fY && m_vEnd.m_fY <= cBB.m_vEnd.m_fY &&
            m_vStart.m_fZ >= cBB.m_vStart.m_fZ && m_vEnd.m_fZ <= cBB.m_vEnd.m_fZ );
    };

bool IsTouching ( const AxisAlignedBoundingBox &  cBB ) const

inline

Returns true if the two boxes intersect at all.

Definition at line 969 of file math.h.

    {
        return (
            m_vStart.m_fX < cBB.m_vEnd.m_fX && m_vEnd.m_fX > cBB.m_vStart.m_fX &&
            m_vStart.m_fY < cBB.m_vEnd.m_fY && m_vEnd.m_fY > cBB.m_vStart.m_fY &&
            m_vStart.m_fZ < cBB.m_vEnd.m_fZ && m_vEnd.m_fZ > cBB.m_vStart.m_fZ );
    };

bool IsTouching	(	const Vector &	vStart,
		const Vector &	vEnd,
		float &	fPlace
	)		const

Returns true if the box intersects any part of a specified line.

If there is an intersection, then a point guaranteed to be inside the box is returned in the third argument (fPlace). That argument represents a location along the line from vStart to vEnd. (Location = vStart + fPlace*vEnd)

Parameters

[in]	vStart	A point (represented as a Vector) defining the start of the line
[in]	vEnd	A point (represented as a Vector) defining the end of the line
[out]	fPlace	A number between 0.0 and 1.0, defining a position along the line that is guaranteed to be inside the box (if true was returned).

bool IsContaining ( const Vector &  cV ) const

inline

Returns true if the box contains the specified point.

Definition at line 992 of file math.h.

    {
        return (
            m_vStart.m_fX <= cV.m_fX && m_vEnd.m_fX >= cV.m_fX &&
            m_vStart.m_fY <= cV.m_fY && m_vEnd.m_fY >= cV.m_fY &&
            m_vStart.m_fZ <= cV.m_fZ && m_vEnd.m_fZ >= cV.m_fZ );
    };

bool IsContaining ( const AxisAlignedBoundingBox &  b ) const

inline

Returns true if the box contains the specified box.

Definition at line 1002 of file math.h.

        { return IsContaining( b.m_vStart ) && IsContaining( b.m_vEnd ); };

AxisAlignedBoundingBox Intersection ( const AxisAlignedBoundingBox &  cOther ) const

inline

Returns the intersection between this box and cOther.

Returned bounding box will be empty if this box does not intersect cOther.

Definition at line 1007 of file math.h.

    {
        if( !IsTouching( cOther ) ) return AxisAlignedBoundingBox();

        return AxisAlignedBoundingBox(
            Vector( 
                Max( cOther.m_vStart.x, m_vStart.x ), 
                Max( cOther.m_vStart.y, m_vStart.y ), 
                Max( cOther.m_vStart.z, m_vStart.z ) ) ,
            Vector( 
                Min( cOther.m_vEnd.x, m_vEnd.x ), 
                Min( cOther.m_vEnd.y, m_vEnd.y ), 
                Min( cOther.m_vEnd.z, m_vEnd.z ) ) );
    }   

bool IsEmpty ( void  ) const

inline

Returns true if the box is empy.

Note that when the start and end corners are equal then the box is not treated as empty.

Definition at line 1024 of file math.h.

{ return m_vStart.x > m_vEnd.x; };

AxisAlignedBoundingBox operator* ( float  fFactor )

inline

Multiplies the box coordinates with a scalar value.

Definition at line 1027 of file math.h.

    {
        return AxisAlignedBoundingBox( m_vStart*fFactor, m_vEnd*fFactor );
    };

static AxisAlignedBoundingBox SphereBoundingBox ( const Vector &  cCenter, float  fRadius, const Matrix &  mTransform  )

static

Returns the bounding box of the given sphere, in the given coordinate space.

Member Data Documentation

Vector m_vStart

Definition at line 1035 of file math.h.

Vector m_vEnd

Definition at line 1036 of file math.h.

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

• Mudbox/math.h