CGAL 5.3 - 3D Fast Intersection and Distance Computation (AABB Tree)
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The concept AABBPrimitive
describes the requirements for the primitives stored in the AABB tree data structure. The concept encapsulates a type for the input datum (a geometric object) and an identifier (id) type through which those primitives are referred to. The concept AABBPrimitive
also refines the concepts DefaultConstructible and Assignable.
Example
The Primitive
type can be, e.g., a wrapper around a Handle
. Assume for instance that the input objects are the triangle faces of a mesh stored as a CGAL::Polyhedron_3
. The Datum
would be a Triangle_3
and the Id
would be a polyhedron Face_handle
. Method datum()
can return either a Triangle_3
constructed on the fly from the face handle or a Triangle_3
stored internally. This provides a way for the user to trade memory for efficiency.
CGAL::AABB_primitive<Id,ObjectPropertyMap,PointPropertyMap,Tag_false,CacheDatum>
CGAL::AABB_segment_primitive<Iterator,CacheDatum>
CGAL::AABB_triangle_primitive<Iterator,CacheDatum>
CGAL::AABB_halfedge_graph_segment_primitive<HalfedgeGraph,VertexPointPMap,Tag_false,CacheDatum>
CGAL::AABB_face_graph_triangle_primitive<FaceGraph,VertexPointPMap,Tag_false,CacheDatum>
Types | |
typedef unspecified_type | Point |
3D point type. | |
typedef unspecified_type | Datum |
Type of input datum. | |
typedef unspecified_type | Point_reference |
Point reference type returned by the function point() . More... | |
typedef unspecified_type | Datum_reference |
Datum reference type returned by the function datum() . More... | |
typedef unspecified_type | Id |
Type of identifiers through which the input objects are referred to. More... | |
Operations | |
Datum_reference | datum () |
returns the datum (geometric object) represented by the primitive. | |
Id | id () |
returns the corresponding identifier. More... | |
Point_reference | reference_point () |
returns a 3D point located on the geometric object represented by the primitive. More... | |
Datum reference type returned by the function datum()
.
It is convertible to the type Datum
.
typedef unspecified_type AABBPrimitive::Id |
Type of identifiers through which the input objects are referred to.
It must be a model of the concepts DefaultConstructible and Assignable.
Point reference type returned by the function point()
.
It is convertible to the type Point
.
Id AABBPrimitive::id | ( | ) |
returns the corresponding identifier.
This identifier is only used as a reference for the objects in the output of the AABB_tree
methods.
Point_reference AABBPrimitive::reference_point | ( | ) |
returns a 3D point located on the geometric object represented by the primitive.
This function is used to sort the primitives during the AABB tree construction as well as to construct the search KD-tree internal to the AABB tree used to accelerate distance queries.