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Merge branch 'develop'

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This commit is contained in:
Andrii Sydorchuk
2014-03-19 21:13:56 +01:00
parent ee47f3103d d662cf4df1
commit 6eb8ea5ab1
1 changed files with 27 additions and 7 deletions
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34
include/boost/polygon/polygon_traits.hpp
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@@ -1129,17 +1129,33 @@ namespace boost { namespace polygon{
template <typename T, typename input_point_type>
typename enable_if<
typename gtl_and< typename is_polygon_90_type<T>::type,
typename gtl_same_type<typename geometry_concept<input_point_type>::type, point_concept>::type>::type,
bool>::type
contains(const T& polygon, const input_point_type& point, bool consider_touch = true) {
typename gtl_and<
typename is_polygon_90_type<T>::type,
typename gtl_same_type<
typename geometry_concept<input_point_type>::type,
point_concept
>::type
>::type,
bool
>::type contains(
const T& polygon,
const input_point_type& point,
bool consider_touch = true) {
typedef T polygon_type;
typedef typename polygon_traits<polygon_type>::coordinate_type coordinate_type;
typedef typename polygon_traits<polygon_type>::iterator_type iterator;
typedef typename std::iterator_traits<iterator>::value_type point_type;
coordinate_type point_x = x(point);
coordinate_type point_y = y(point);
bool inside = false;
// Check how many intersections has the ray extended from the given
// point in the x-axis negative direction with the polygon edges.
// If the number is odd the point is within the polygon, otherwise not.
// We can safely ignore horizontal edges, however intersections with
// end points of the vertical edges require special handling. We should
// add one intersection in case horizontal edges that extend vertical edge
// point in the same direction.
int num_full_intersections = 0;
int num_half_intersections = 0;
for (iterator iter = begin_points(polygon); iter != end_points(polygon);) {
point_type curr_point = *iter;
++iter;
@@ -1154,7 +1170,10 @@ namespace boost { namespace polygon{
if (x(curr_point) == point_x) {
return consider_touch;
}
inside ^= true;
++num_full_intersections;
}
if (point_y == min_y || point_y == max_y) {
num_half_intersections += (y(curr_point) < y(next_point) ? 1 : -1);
}
} else {
coordinate_type min_x = (std::min)(x(curr_point), x(next_point));
@@ -1166,7 +1185,8 @@ namespace boost { namespace polygon{
}
}
}
return inside;
int total_intersections = num_full_intersections + (num_half_intersections >> 1);
return total_intersections & 1;
}
//TODO: refactor to expose as user APIs