The function surface_neighbor_coordinates_3 computes natural neighbor coordinates for surface points associated to a finite set of sample points issued from the surface. The coordinates are computed from the intersection of the Voronoi cell of the query point p with the tangent plane to the surface at p. If the sampling is sufficiently dense, the coordinate system meets the properties described in the manual pages and in [BF02],[Flö03b]. The query point p needs to lie inside the convex hull of the projection of the sample points onto the tangent plane at p.
#include <CGAL/surface_neighbor_coordinates_3.h>
| ||||
| ||||
| ||||
The sample points P are provided in the range
[.first, beyond.).
InputIterator::value_type is the point type
Kernel::Point_3. The tangent plane is defined by the point
p and the vector normal. The parameter K
determines the kernel type that will instantiate
the template parameter of Voronoi_intersection_2_traits_3<K>. The natural neighbor coordinates for p are computed in the power diagram that results from the intersection of the 3D Voronoi diagram of P with the tangent plane. The sequence of point/coordinate pairs that is computed by the function is placed starting at out. The function returns a triple with an iterator that is placed past-the-end of the resulting sequence of point/coordinate pairs, the normalization factor of the coordinates and a Boolean value which is set to true iff the coordinate computation was successful, i.e. if p lies inside the convex hull of the projection of the points P onto the tangent plane. | ||||
| ||||
| ||||
| ||||
the same as above only that the traits class must be instantiated by the user. ITraits must be equivalent to Voronoi_intersection_2_traits_3<K>. |
The next functions return, in addition, a second Boolean value (the fourth value of the quadruple) that certifies whether or not, the Voronoi cell of p can be affected by points that lie outside the input range, i.e. outside the ball centered on p passing through the furthest sample point from p in the range [.first, beyond.). If the sample points are collected by a k-nearest neighbor or a range search query, this permits to check whether the neighborhood which has been considered is large enough.
| ||||
| ||||
| ||||
Similar to the first function. The additional fourth return value is true if the furthest point in the range [.first, beyond.) is further away from p than twice the distance from p to the furthest vertex of the intersection of the Voronoi cell of p with the tangent plane defined by (p,normal). It is false otherwise. | ||||
| ||||
| ||||
| ||||
The same as above except that this function takes the maximal distance from p to the points in the range [.first, beyond.) as additional parameter. | ||||
| ||||
| ||||
| ||||
The same as above only that the traits class must be instantiated by the user and without the parameter max_distance. ITraits must be equivalent to Voronoi_intersection_2_traits_3<K>. | ||||
| ||||
| ||||
| ||||
The same as above with the parameter max_distance. |
The next function allows to filter some potential neighbors of the query point p from P via its three-dimensional Delaunay triangulation. All surface neighbors of p are necessarily neighbors in the Delaunay triangulation of P ∪ {p}.
| ||||
| ||||
| ||||
computes the surface neighbor coordinates with respect to the points that are vertices of the Delaunay triangulation dt. The type Dt must be equivalent to Delaunay_triangulation_3<Gt, Tds>. The optional parameter start is used as a starting place for the search of the conflict zone. It may be the result of the call dt.locate(p). This function instantiates the template parameter ITraits to be Voronoi_intersection_2_traits_3<Dt::Geom_traits>. | ||||
| ||||
| ||||
| ||||
The same as above only that the parameter traits instantiates the geometric traits class. Its type ITraits must be equivalent to Voronoi_intersection_2_traits_3<K>. |