MBMesquite::MsqSphere Class Reference

Sphere. More...

#include <MsqGeomPrim.hpp>

Collaboration diagram for MBMesquite::MsqSphere:

Public Member Functions
	MsqSphere (const Vector3D &p_center, double p_radius)
const Vector3D &	center () const
double	radius () const
Vector3D	closest (const Vector3D &point) const
bool	closest (const Vector3D &point, Vector3D &point_on_sphere, Vector3D &normal_at_point) const
double	distance (const Vector3D &point) const
bool	intersect (const MsqPlane &plane, MsqCircle &result) const
bool	intersect (const MsqSphere &sphere, MsqCircle &result) const
Private Attributes
Vector3D	mCenter
double	mRadius

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Detailed Description

Sphere.

Definition at line 197 of file MsqGeomPrim.hpp.

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Constructor & Destructor Documentation

MBMesquite::MsqSphere::MsqSphere	(	const Vector3D &	p_center,
		double	p_radius
	)		[inline]

Definition at line 204 of file MsqGeomPrim.hpp.

: mCenter( p_center ), mRadius( p_radius ) {}

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Member Function Documentation

const Vector3D& MBMesquite::MsqSphere::center

(

)

const [inline]

Definition at line 206 of file MsqGeomPrim.hpp.

Referenced by closest(), intersect(), GeomPrimTest::test_sphere_basic(), GeomPrimTest::test_sphere_intersect_plane(), and GeomPrimTest::test_sphere_intersect_sphere().

    {
        return mCenter;
    }

Vector3D MBMesquite::MsqSphere::closest

(

const Vector3D &

point

)

const

Get location on sphere closest to input location. Returns arbitrary point if input location is at center.

Definition at line 158 of file MsqGeomPrim.cpp.

References center(), MBMesquite::Vector3D::length(), and radius().

Referenced by GeomPrimTest::test_sphere_closest_to_point().

{
    Vector3D diff = point - center();
    double len    = diff.length();
    if( len < DBL_EPSILON )
    {
        // pick any point
        diff = Vector3D( 1, 0, 0 );
        len  = 1;
    }

    return center() + diff * radius() / len;
}

bool MBMesquite::MsqSphere::closest	(	const Vector3D &	point,
		Vector3D &	point_on_sphere,
		Vector3D &	normal_at_point
	)		const

Get location on sphere closest to input location, and normal at closest point.

Returns:

false if input point is at center, true otherwise.

Definition at line 172 of file MsqGeomPrim.cpp.

References center(), MBMesquite::Vector3D::length(), and radius().

{
    normal_at_point = point - center();
    double len      = normal_at_point.length();
    if( len < DBL_EPSILON ) return false;

    normal_at_point /= len;
    point_on_sphere = center() + radius() * normal_at_point;
    return true;
}

double MBMesquite::MsqSphere::distance

(

const Vector3D &

point

)

const [inline]

Definition at line 224 of file MsqGeomPrim.hpp.

References center(), MBMesquite::length(), and radius.

Referenced by GeomPrimTest::test_sphere_intersect_sphere().

    {
        return fabs( ( center() - point ).length() - radius() );
    }

bool MBMesquite::MsqSphere::intersect	(	const MsqPlane &	plane,
		MsqCircle &	result
	)		const

Intersect plane with sphere

Returns:

true if intersection exists, false otherwise.

Definition at line 183 of file MsqGeomPrim.cpp.

References center(), MBMesquite::MsqPlane::closest(), MBMesquite::Vector3D::length_squared(), MBMesquite::MsqPlane::normal(), and radius().

Referenced by GeomPrimTest::test_sphere_intersect_plane(), and GeomPrimTest::test_sphere_intersect_sphere().

{
    const Vector3D plane_pt  = plane.closest( center() );
    const Vector3D plane_dir = plane_pt - center();
    const double dir_sqr     = plane_dir.length_squared();
    if( dir_sqr < DBL_EPSILON )
    {  // plane passes through center of sphere
        result = MsqCircle( center(), plane.normal(), radius() );
        return true;
    }

    double rad_sqr = radius() * radius() - plane_dir.length_squared();
    if( rad_sqr < 0 )  // no intersection
        return false;

    result = MsqCircle( plane_pt, plane_dir, sqrt( rad_sqr ) );
    return true;
}

bool MBMesquite::MsqSphere::intersect	(	const MsqSphere &	sphere,
		MsqCircle &	result
	)		const

Intersect spheres

Returns:

true if intersection exists, false otherwise.

Definition at line 202 of file MsqGeomPrim.cpp.

References center(), dist(), MBMesquite::Vector3D::length(), and radius().

{
    const Vector3D d  = sphere.center() - center();
    const double dist = d.length();
    if( dist > ( radius() + sphere.radius() ) ) return false;

    const double r1_sqr = radius() * radius();
    const double r2_sqr = sphere.radius() * sphere.radius();
    const double f      = ( d % d + r1_sqr - r2_sqr ) / 2;
    // const double d1 = f / dist;

    const double rad = sqrt( r1_sqr - f * f / ( d % d ) );
    Vector3D c       = center() + d * f / ( d % d );
    result           = MsqCircle( c, d, rad );
    return true;
}

double MBMesquite::MsqSphere::radius

(

)

const [inline]

Definition at line 210 of file MsqGeomPrim.hpp.

Referenced by closest(), intersect(), GeomPrimTest::test_sphere_basic(), GeomPrimTest::test_sphere_intersect_plane(), and GeomPrimTest::test_sphere_intersect_sphere().

    {
        return mRadius;
    }

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Member Data Documentation

Vector3D MBMesquite::MsqSphere::mCenter [private]

Definition at line 200 of file MsqGeomPrim.hpp.

double MBMesquite::MsqSphere::mRadius [private]

Definition at line 201 of file MsqGeomPrim.hpp.

List of all members.

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

• MsqGeomPrim.hpp
• MsqGeomPrim.cpp