pbat::geometry::sdf::Composite< TScalar > Struct Template Reference

Composite signed distance function represented as a forest of SDFs. More...

#include <Composite.h>

Public Types
using	ScalarType = TScalar
	Scalar type.

Public Member Functions
PBAT_HOST_DEVICE	Composite (std::span< Node< ScalarType > const > nodes, std::span< Transform< ScalarType > const > transforms, std::span< std::pair< int, int > const > children, std::span< int const > roots)
	Construct a composite SDF from nodes, transforms, children, ancestors and roots.
PBAT_HOST_DEVICE ScalarType	Eval (Vec3< ScalarType > const &p) const
	Evaluate the signed distance function at a given point.
PBAT_HOST_DEVICE ScalarType	Eval (int n, Vec3< ScalarType > const &p) const
	Evaluate the signed distance function rooted in node n at a given point p.
PBAT_HOST_DEVICE Vec3< ScalarType >	Grad (Vec3< ScalarType > const &p, ScalarType h) const
	Evaluate the (numerical) gradient of the signed distance function at a given point using a central difference scheme.
PBAT_HOST_DEVICE ECompositeStatus	Status () const
	Get the status of the composite SDF.

Public Attributes
std::span< Node< ScalarType > const >	mNodes
	|# nodes| nodes in the composite SDF
std::span< Transform< ScalarType > const >	mTransforms
	|# nodes| transforms associated to each node
std::span< std::pair< int, int > const >	mChildren
std::span< int const >	mRoots
	|# roots| root indices of the composite SDF
ECompositeStatus	mStatus
	Status of the composite SDF.

Detailed Description

template<common::CArithmetic TScalar>
struct pbat::geometry::sdf::Composite< TScalar >

Composite signed distance function represented as a forest of SDFs.

Constructor & Destructor Documentation

Composite()

template<common::CArithmetic TScalar>

pbat::geometry::sdf::Composite< TScalar >::Composite ( std::span< Node< ScalarType > const > nodes, std::span< Transform< ScalarType > const > transforms, std::span< std::pair< int, int > const > children, std::span< int const > roots )

inline

Construct a composite SDF from nodes, transforms, children, ancestors and roots.

Parameters

nodes	Span of nodes in the composite SDF
transforms	Span of transforms associated to each node
children	Span of pairs of children indices for each node, such that c* < 0 if no child
roots	Span of root indices of the composite SDF

Member Function Documentation

Eval() [1/2]

template<common::CArithmetic TScalar>

TScalar pbat::geometry::sdf::Composite< TScalar >::Eval ( int n, Vec3< ScalarType > const & p ) const

inline

Evaluate the signed distance function rooted in node n at a given point p.

Parameters

n	Index of the root node
p	Point at which to evaluate the SDF

Returns

Signed distance to the composite shape rooted in node n

Eval() [2/2]

template<common::CArithmetic TScalar>

TScalar pbat::geometry::sdf::Composite< TScalar >::Eval ( Vec3< ScalarType > const & p ) const

inline

Evaluate the signed distance function at a given point.

Parameters

p	Point at which to evaluate the SDF

Returns

Signed distance to the composite shape

Grad()

template<common::CArithmetic TScalar>

Vec3< TScalar > pbat::geometry::sdf::Composite< TScalar >::Grad ( Vec3< ScalarType > const & p, ScalarType h ) const

inline

Evaluate the (numerical) gradient of the signed distance function at a given point using a central difference scheme.

We use the tetrahedron technique described in https://iquilezles.org/articles/normalsSDF/

Parameters

p	Point at which to evaluate the gradient
h	Finite difference step size

Returns

Numerical gradient of the signed distance function at point p

Status()

template<common::CArithmetic TScalar>

PBAT_HOST_DEVICE ECompositeStatus pbat::geometry::sdf::Composite< TScalar >::Status ( ) const

inline

Get the status of the composite SDF.

Returns

Status of the composite SDF

Member Data Documentation

mChildren

template<common::CArithmetic TScalar>

std::span<std::pair<int, int> const> pbat::geometry::sdf::Composite< TScalar >::mChildren

|# nodes| children pairs (ci, cj) of each node, such that c* < 0 if no child. A binary node n has 2 children stored in (ci, cj), a unary node n has 1 child stored in ci, and a primitive has no children.

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

• C:/git/PhysicsBasedAnimationToolkit/source/pbat/geometry/sdf/Composite.h