circleLine Class Reference

Circle and line intersection test. More...

#include <mathlib.h>

List of all members.

Static Public Member Functions
template<typename PT , typename PD >
static boolc	intersection2D (PT &p0, PT &p1, PD const radius, PT const &q0, PT const &q1)
	Find the intersection of the line with points q0 and q1 with the circle at the origin.

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Detailed Description

Circle and line intersection test.

Definition at line 583 of file mathlib.h.

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Member Function Documentation

template<typename PT , typename PD >

boolc circleLine::intersection2D	(	PT &	p0,
		PT &	p1,
		PD const	radius,
		PT const &	q0,
		PT const &	q1
	)			[inline, static]

Find the intersection of the line with points q0 and q1 with the circle at the origin.

Assumes that the points are 2D.

Definition at line 610 of file mathlib.h.

References solvequadratic().

Referenced by disk::intersects(), and mathlibtest::test015().

{
  assert( zero<PD>::test( (q0-q1).dot()) == false );

  // Hard coded type. No templated solvequadratic.

  PT B(q1-q0);

  doublec a = B.dot();
  doublec b = q0.dot(B)*2.0;
  doublec c = q0.dot()-radius*radius;
  double t0;
  double t1;
  bool res;
  res = solvequadratic(t0,t1,a,b,c);
  if (res==false)
    return false;

  p0 = q0 + B*t0;
  p1 = q0 + B*t1;

  return true;
}

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

• mathlib/mathlib.h