EBGeometry::RoundedCylinderSDF< T > Class Template Reference

Signed distance field for a cylinder with rounded (toroidal) edges. More...

#include <EBGeometry_AnalyticDistanceFunctions.hpp>

Public Member Functions
	RoundedCylinderSDF ()=default
	Default constructor. Constructs a rounded cylinder centered at the origin, axis along y, with outer radius 1, total height 1, and edge curvature 0.1.
	RoundedCylinderSDF (const Vec3T< T > &a_center, const T a_radius, const T a_curvature, const T a_height) noexcept
	Full constructor.
	RoundedCylinderSDF (const RoundedCylinderSDF &)=default
	Copy constructor.
	RoundedCylinderSDF (RoundedCylinderSDF &&)=default
	Move constructor.
RoundedCylinderSDF &	operator= (const RoundedCylinderSDF &)=default
	Copy assignment.
RoundedCylinderSDF &	operator= (RoundedCylinderSDF &&)=default
	Move assignment.
T	signedDistance (const Vec3T< T > &a_point) const noexcept
	Signed distance function for the rounded cylinder.
BoundingVolumes::AABBT< T >	computeBoundingVolume () const noexcept
	The shape's axis-aligned bounding box.

Static Public Attributes
static constexpr DistanceQuality	distanceQuality = DistanceQuality::Exact
	How far signedDistance() can be trusted as a distance: the Euclidean distance to the surface.

Protected Attributes
Vec3T< T >	m_center = Vec3T<T>::zeros()
	Cylinder center.
T	m_majorRadius = T(0.9)
	Inner cylinder radius (= outer radius - curvature).
T	m_minorRadius = T(0.1)
	Edge rounding radius (= curvature).
T	m_height = T(0.4)
	Inner half-height (= 0.5*height - curvature).

Detailed Description

template<class T>
class EBGeometry::RoundedCylinderSDF< T >

Signed distance field for a cylinder with rounded (toroidal) edges.

The cylinder is centered at m_center with its axis along y. The constructor takes the center, the outer radius, the edge curvature radius and the total height. The curvature rounds the sharp edges where the flat caps meet the cylindrical wall; the resulting shape is sometimes called a "stadium of revolution" or a "pill cylinder".

Internally three derived parameters are stored:

• m_majorRadius = a_radius - a_curvature: radius of the inner cylindrical core (before edge rounding).
• m_minorRadius = a_curvature: radius of the torus-like edge rounding.
• m_height = 0.5 * a_height - a_curvature: half-height of the inner cylindrical core (before edge rounding).

The outer bounding cylinder has radius m_majorRadius + m_minorRadius = a_radius and half-height m_height + m_minorRadius = 0.5 * a_height. For the geometry to be valid, a_curvature must be strictly less than a_radius and less than 0.5 * a_height.

The SDF is negative inside and positive outside. By default the cylinder has outer radius 1, height 1, and edge curvature 0.1 (stored as m_majorRadius=0.9, m_minorRadius=0.1, m_height=0.4).

Template Parameters

T	Floating-point precision.

Constructor & Destructor Documentation

RoundedCylinderSDF()

template<class T >

EBGeometry::RoundedCylinderSDF< T >::RoundedCylinderSDF ( const Vec3T< T > &  a_center, const T  a_radius, const T  a_curvature, const T  a_height  )

inlinenoexcept

Full constructor.

Parameters

[in]	a_center	Cylinder center.
[in]	a_radius	Outer cylinder radius. Must be > 0 and > a_curvature.
[in]	a_curvature	Edge rounding radius. Must be > 0 and satisfy a_curvature < a_radius and 2 * a_curvature < a_height.
[in]	a_height	Total cylinder height. Must be > 0 and > 2 * a_curvature.

Member Function Documentation

computeBoundingVolume()

template<class T >

BoundingVolumes::AABBT< T > EBGeometry::RoundedCylinderSDF< T >::computeBoundingVolume ( ) const

inlinenoexcept

The shape's axis-aligned bounding box.

The outer radius either side of the axis in x and z, and half the height in y.

Returns

The bounding box.

operator=() [1/2]

template<class T >

RoundedCylinderSDF & EBGeometry::RoundedCylinderSDF< T >::operator= ( const RoundedCylinderSDF< T > &  )

default

Copy assignment.

Returns

Reference to (*this).

operator=() [2/2]

template<class T >

RoundedCylinderSDF & EBGeometry::RoundedCylinderSDF< T >::operator= ( RoundedCylinderSDF< T > &&  )

default

Move assignment.

Returns

Reference to (*this).

signedDistance()

template<class T >

T EBGeometry::RoundedCylinderSDF< T >::signedDistance ( const Vec3T< T > &  a_point ) const

inlinenoexcept

Signed distance function for the rounded cylinder.

Parameters

[in]

a_point

Position.

Returns

Signed distance from a_point to the rounded-cylinder surface; negative inside.

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

• Source/EBGeometry_AnalyticDistanceFunctions.hpp