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Adding an option to construct half-theta and half-Yao graphs

This commit is contained in:
Frédérik Paradis 2016-11-08 13:53:32 -05:00
parent 340133a0e4
commit 9e0fc621e5
2 changed files with 26 additions and 12 deletions
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21
Cone_spanners_2/include/CGAL/Construct_theta_graph_2.h
View File

@ -44,11 +44,11 @@ namespace CGAL {
\brief A template functor for constructing Theta graphs with a given set of 2D points and \brief A template functor for constructing Theta graphs with a given set of 2D points and
a given initial direction for the cone boundaries. a given initial direction for the cone boundaries.
\tparam Traits_ Must be either `CGAL::Exact_predicates_exact_constructions_kernel_with_root_of` \tparam Traits_ Must be either `CGAL::Exact_predicates_exact_constructions_kernel_with_root_of`
or `CGAL::Exact_predicates_inexact_constructions_kernel`. or `CGAL::Exact_predicates_inexact_constructions_kernel`.
\tparam Graph_ The graph type to store the constructed cone based spanner. \tparam Graph_ The graph type to store the constructed cone based spanner.
It must be <A HREF="http://www.boost.org/libs/graph/doc/adjacency_list.html">`boost::adjacency_list`</A> It must be <A HREF="http://www.boost.org/libs/graph/doc/adjacency_list.html">`boost::adjacency_list`</A>
with `Traits_::Point_2` as `VertexProperties`. with `Traits_::Point_2` as `VertexProperties`.
*/ */
template <typename Traits_, typename Graph_> template <typename Traits_, typename Graph_>
@ -78,6 +78,9 @@ private:
/* Store the number of cones. */ /* Store the number of cones. */
unsigned int cone_number; unsigned int cone_number;
/* Store wheter this is an half-theta graph */
bool half;
/* Store the directions of the rays dividing the plane. The initial direction will be /* Store the directions of the rays dividing the plane. The initial direction will be
* stored in rays[0]. * stored in rays[0].
*/ */
@ -90,10 +93,13 @@ public:
\param initial_direction A direction denoting one of the rays dividing the \param initial_direction A direction denoting one of the rays dividing the
cones. This allows arbitary rotations of the rays that divide cones. This allows arbitary rotations of the rays that divide
the plane. (default: positive x-axis) the plane. (default: positive x-axis)
\param half_theta Indicates whether all the cones are used or just half of
them (default: all cones).
*/ */
Construct_theta_graph_2 (unsigned int k, Construct_theta_graph_2 (unsigned int k,
Direction_2 initial_direction = Direction_2(1,0) Direction_2 initial_direction = Direction_2(1,0),
): cone_number(k), rays(std::vector<Direction_2>(k)) bool half_theta = false
): cone_number(k), rays(std::vector<Direction_2>(k)), half(half_theta)
{ {
if (k<2) { if (k<2) {
@ -131,7 +137,8 @@ public:
unsigned int j; // index of the ccw ray unsigned int j; // index of the ccw ray
// add edges into the graph for every cone // add edges into the graph for every cone
for (i = 0; i < cone_number; i++) { int increment = half ? 2 : 1;
for (i = 0; i < cone_number; i += increment) {
j = (i+1) % cone_number; j = (i+1) % cone_number;
add_edges_in_cone(rays[i], rays[j], g); add_edges_in_cone(rays[i], rays[j], g);
} }
@ -201,10 +208,10 @@ protected:
Less_by_direction > PSTree; Less_by_direction > PSTree;
PSTree pst(orderD2, orderMid); PSTree pst(orderD2, orderMid);
// Step 3: visit S in orderD1 // Step 3: visit S in orderD1
// insert '*it' into T // insert '*it' into T
// find ri = T.minAbove(*it) // find ri = T.minAbove(*it)
// add an edge // add an edge
for (typename std::vector<typename Graph_::vertex_descriptor>::const_iterator for (typename std::vector<typename Graph_::vertex_descriptor>::const_iterator
it = S.begin(); it != S.end(); ++it) { it = S.begin(); it != S.end(); ++it) {
pst.add(*it, *it); pst.add(*it, *it);

17
Cone_spanners_2/include/CGAL/Construct_yao_graph_2.h
View File

@ -42,11 +42,11 @@ namespace CGAL {
\brief A template functor for constructing Yao graphs with a given set of 2D points and \brief A template functor for constructing Yao graphs with a given set of 2D points and
a given initial direction for the cone boundaries. a given initial direction for the cone boundaries.
\tparam Traits_ Must be either `CGAL::Exact_predicates_exact_constructions_kernel_with_root_of` \tparam Traits_ Must be either `CGAL::Exact_predicates_exact_constructions_kernel_with_root_of`
or `CGAL::Exact_predicates_inexact_constructions_kernel`. or `CGAL::Exact_predicates_inexact_constructions_kernel`.
\tparam Graph_ The graph type to store the constructed cone based spanner. \tparam Graph_ The graph type to store the constructed cone based spanner.
It must be <A HREF="http://www.boost.org/libs/graph/doc/adjacency_list.html">`boost::adjacency_list`</A> It must be <A HREF="http://www.boost.org/libs/graph/doc/adjacency_list.html">`boost::adjacency_list`</A>
with `Traits_::Point_2` as `VertexProperties` with `Traits_::Point_2` as `VertexProperties`
*/ */
template <typename Traits_, typename Graph_> template <typename Traits_, typename Graph_>
@ -73,6 +73,9 @@ private:
/* Store the number of cones. */ /* Store the number of cones. */
unsigned int cone_number; unsigned int cone_number;
/* Store wheter this is an half-theta graph */
bool half;
/* Store the directions of the rays dividing the plane. The initial direction will be /* Store the directions of the rays dividing the plane. The initial direction will be
stored in rays[0]. */ stored in rays[0]. */
std::vector<Direction_2> rays; std::vector<Direction_2> rays;
@ -85,10 +88,13 @@ public:
\param initial_direction A direction denoting one of the rays dividing the \param initial_direction A direction denoting one of the rays dividing the
cones. This allows arbitary rotations of the rays that divide cones. This allows arbitary rotations of the rays that divide
the plane. (default: positive x-axis) the plane. (default: positive x-axis)
\param half_yao Indicates whether all the cones are used or just half of
them (default: all cones).
*/ */
Construct_yao_graph_2 (unsigned int k, Construct_yao_graph_2 (unsigned int k,
Direction_2 initial_direction = Direction_2(1,0) Direction_2 initial_direction = Direction_2(1,0),
): cone_number(k), rays(std::vector<Direction_2>(k)) bool half_yao = false
): cone_number(k), rays(std::vector<Direction_2>(k)), half(half_yao)
{ {
if (k<2) { if (k<2) {
@ -127,7 +133,8 @@ public:
unsigned int j; // index of the ccw ray unsigned int j; // index of the ccw ray
// add edges into the graph for every cone // add edges into the graph for every cone
for (i = 0; i < cone_number; i++) { int increment = half ? 2 : 1;
for (i = 0; i < cone_number; i += increment) {
j = (i+1) % cone_number; j = (i+1) % cone_number;
add_edges_in_cone(rays[i], rays[j], g); add_edges_in_cone(rays[i], rays[j], g);
} }