Eagle::BoundingBall Class Reference

Bounding container implemented by a ball. More...

#include </home/werner/origo/vish/ocean/aerie/BoundingBall.hpp>

List of all members.

Public Types

• typedef
  Eagle::PhysicalSpace::tvector tvector

Public Member Functions

• BoundingBall ()

  Default bounding ball, sets radius to zero, center to (0,0,0)
  

• BoundingBall (const point_t &Center, double R)

  Construct with Center and Radius.
  

• BoundingBall (double R, const point_t &Center)

  Construct with Radius and Center.
  

• BoundingBall (const BoundingBall &BB)

  Copy constructor.
  

• const point_t & center () const

  The center of the bounding ball.
  

• void expandBall (const point_t &point)

  Expand ball by point, using the algorithm http://geometryalgorithms.com/Archive/algorithm_0107/algorithm_0107.htm#fastBall() .
  

• void expandBall (const BoundingBall &B)

  Expand a ball by another ball.
  

• point_t & getCenter ()

  The center of the bounding ball.
  

• double getRadius () const

  The radius of the bounding ball.
  

• virtual bool inside (const point_t &p) const
• virtual MemCore::RefPtr
  < BoundingBall > merge (const MemCore::RefPtr< BoundingBall > &Src) const
• BoundingBall & operator+= (const BoundingBall &B)
• double radius () const

  The radius of the bounding ball.
  

• double radius2 () const

  The squared radius of the bounding ball.
  

• void setCenter (const point_t &center)

  Set the center of the bounding ball.
  

• void setRadius (double R)

  The radius of the bounding ball.
  

• ~BoundingBall ()

  Destructor.
  

Protected Attributes

• point_t Center
• double Radius
• double Radius2

Friends

• bool operator& (const BoundingBall &A, const BoundingBall &B)

  Operator version to check whether two bounding balls overlap.
  

• bool overlap (const BoundingBall &, const BoundingBall &)

  Check whether two bounding balls overlap.
  

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Detailed Description

Bounding container implemented by a ball.

See also http://geometryalgorithms.com/Archive/algorithm_0107/algorithm_0107.htm

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Member Function Documentation

void Eagle::BoundingBall::expandBall

(

const point_t &

point

)

Expand ball by point, using the algorithm http://geometryalgorithms.com/Archive/algorithm_0107/algorithm_0107.htm#fastBall() .

This algorithm is pretty slow (even though it is called fastBall ), as it involves a sqrt() function call and several vector operations. If speed is crucial, better use a BoundingBox to expand by points, and then use a global operation BoundingBox::updateBall() to compute the bounding ball. However, the bounding ball computed this way will be not as tight around the points like a ball built from expandBall() calls.

Note:

If the point is contained int the ball, then the cost of this function is (6add,3mul) operations. If not, then the cost is increased by (1sqrt, 5add, 6mul).

void Eagle::BoundingBall::expandBall

(

const BoundingBall &

B

)

Expand a ball by another ball.

Note that this function is not necessarily the fastest.

Todo:

Check whether there is a faster way to implement void BoundingBall::expandBall(const BoundingBall&B)

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

• ocean/aerie/BoundingBall.hpp
• ocean/aerie/BoundingBall.cpp