AABB< Scalar, Dim > Class Template Reference

Axis-Aligned Bounding Box (AABB) tree for efficient spatial queries. More...

#include <lagrange/bvh/AABB.h>

Public Types
using	Index = uint32_t
using	Box = Eigen::AlignedBox<Scalar, Dim>
using	Point = typename Box::VectorType

Public Member Functions
void	build (span< Box > boxes)
	Build the AABB tree from a collection of bounding boxes.
void	intersect (const Box &query_box, std::vector< Index > &results) const
	Find all boxes that intersect with a query box.
void	intersect (const Box &query_box, function_ref< bool(Index)> callback) const
	Find all boxes that intersect with a query box and call a function for each.
Index	intersect_first (const Box &query_box) const
	Find the first box that intersects with a query box.
Index	get_closest_element (const Point &q, function_ref< Scalar(Index)> sq_dist_fn) const
	Find the index of the closest element to a query point.
void	foreach_element_within_radius (const Point &q, Scalar sq_radius, function_ref< void(Index)> func) const
	Call a function for each element within a given radius from a query point.
bool	empty () const
	Check if the tree is empty.

Detailed Description

template<typename Scalar, int Dim>
class lagrange::bvh::AABB< Scalar, Dim >

Axis-Aligned Bounding Box (AABB) tree for efficient spatial queries.

This data structure organizes a collection of bounding boxes in a binary tree to enable fast intersection queries. The tree is built using a top-down approach by recursively splitting boxes along the longest Dimension of their centroids.

Template Parameters

Scalar	Numeric type for coordinates (e.g., float or double).
Dim	Spatial Dimension (2 or 3).

Member Function Documentation

build()

template<typename Scalar, int Dim>

void build

(

span< Box >

boxes

)

Build the AABB tree from a collection of bounding boxes.

Parameters

[in]

boxes

Input bounding boxes to organize in the tree.

intersect() [1/2]

template<typename Scalar, int Dim>

void intersect	(	const Box &	query_box,
		std::vector< Index > &	results ) const

Find all boxes that intersect with a query box.

Parameters

[in]	query_box	The query bounding box.
[out]	results	Indices of boxes that intersect with the query box.

intersect() [2/2]

template<typename Scalar, int Dim>

void intersect	(	const Box &	query_box,
		function_ref< bool(Index)>	callback ) const

Find all boxes that intersect with a query box and call a function for each.

Parameters

[in]	query_box	The query bounding box.
[in]	callback	Function to call for each intersecting box index. The callback function takes an element ID as input and returns a bool indicating whether to continue the search (true) or terminate early (false).

intersect_first()

template<typename Scalar, int Dim>

AABB< Scalar, Dim >::Index intersect_first

(

const Box &

query_box

)

const

Find the first box that intersects with a query box.

Parameters

[in]

query_box

The query bounding box.

Returns

Element ID of the first intersecting box, or invalid<Index>() if none found.

get_closest_element()

template<typename Scalar, int Dim>

AABB< Scalar, Dim >::Index get_closest_element	(	const Point &	q,
		function_ref< Scalar(Index)>	sq_dist_fn ) const

Find the index of the closest element to a query point.

Parameters

[in]	q	The query point.
[in]	sq_dist_fn	Squared distance function for point-element distance.

Returns

Index of the closest element, or invalid<Index>() if tree is empty.

foreach_element_within_radius()

template<typename Scalar, int Dim>

void foreach_element_within_radius	(	const Point &	q,
		Scalar	sq_radius,
		function_ref< void(Index)>	func ) const

Call a function for each element within a given radius from a query point.

Parameters

[in]	q	The query point.
[in]	sq_radius	The search radius squared.
[in]	func	Function to call for each element whose bounding box is within the radius.

Remarks

This method checks bounding boxes, not exact geometry.

empty()

template<typename Scalar, int Dim>

bool empty ( ) const

inline

Check if the tree is empty.

Returns

True if the tree is empty, false otherwise.

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

• lagrange/bvh/AABB.h
• types/AABB.cpp