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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
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`.
\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`.
*/
template <typename Traits_, typename Graph_>
@ -78,6 +78,9 @@ private:
/* Store the number of cones. */
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
* stored in rays[0].
*/
@ -90,10 +93,13 @@ public:
\param initial_direction A direction denoting one of the rays dividing the
cones. This allows arbitary rotations of the rays that divide
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,
Direction_2 initial_direction = Direction_2(1,0)
): cone_number(k), rays(std::vector<Direction_2>(k))
Direction_2 initial_direction = Direction_2(1,0),
bool half_theta = false
): cone_number(k), rays(std::vector<Direction_2>(k)), half(half_theta)
{
if (k<2) {
@ -131,7 +137,8 @@ public:
unsigned int j; // index of the ccw ray
// 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;
add_edges_in_cone(rays[i], rays[j], g);
}
@ -201,10 +208,10 @@ protected:
Less_by_direction > PSTree;
PSTree pst(orderD2, orderMid);
// Step 3: visit S in orderD1
// Step 3: visit S in orderD1
// insert '*it' into T
// find ri = T.minAbove(*it)
// add an edge
// add an edge
for (typename std::vector<typename Graph_::vertex_descriptor>::const_iterator
it = S.begin(); it != S.end(); ++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
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`.
\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`
*/
template <typename Traits_, typename Graph_>
@ -73,6 +73,9 @@ private:
/* Store the number of cones. */
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
stored in rays[0]. */
std::vector<Direction_2> rays;
@ -85,10 +88,13 @@ public:
\param initial_direction A direction denoting one of the rays dividing the
cones. This allows arbitary rotations of the rays that divide
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,
Direction_2 initial_direction = Direction_2(1,0)
): cone_number(k), rays(std::vector<Direction_2>(k))
Direction_2 initial_direction = Direction_2(1,0),
bool half_yao = false
): cone_number(k), rays(std::vector<Direction_2>(k)), half(half_yao)
{
if (k<2) {
@ -127,7 +133,8 @@ public:
unsigned int j; // index of the ccw ray
// 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;
add_edges_in_cone(rays[i], rays[j], g);
}