static inline bool apply(Multi const& multi,
Point& centroid,
Strategy const& strategy)
{
#if ! defined(BOOST_GEOMETRY_CENTROID_NO_THROW)
// If there is nothing in any of the ranges, it is not possible
// to calculate the centroid
if (geometry::is_empty(multi))
{
throw centroid_exception();
}
#endif
// prepare translation transformer
translating_transformer<Multi> transformer(multi);
typename Strategy::state_type state;
for (typename boost::range_iterator<Multi const>::type
it = boost::begin(multi);
it != boost::end(multi);
++it)
{
Policy::apply(*it, transformer, strategy, state);
}
if ( strategy.result(state, centroid) )
{
// translate the result back
transformer.apply_reverse(centroid);
return true;
}
return false;
}
static inline void apply(Multi const& multi, Point& centroid,
Strategy const& strategy)
{
// If there is nothing in any of the ranges, it is not possible
// to calculate the centroid
if (geometry::num_points(multi) == 0)
{
throw centroid_exception();
}
typename Strategy::state_type state;
for (typename boost::range_iterator<Multi const>::type
it = boost::begin(multi);
it != boost::end(multi);
++it)
{
Policy::apply(*it, strategy, state);
}
Strategy::result(state, centroid);
}
inline bool range_ok(Range const& range, Point& centroid)
{
std::size_t const n = boost::size(range);
if (n > 1)
{
return true;
}
else if (n <= 0)
{
#if ! defined(BOOST_GEOMETRY_CENTROID_NO_THROW)
throw centroid_exception();
#endif
return false;
}
else // if (n == 1)
{
// Take over the first point in a "coordinate neutral way"
geometry::convert(*boost::begin(range), centroid);
return false;
}
return true;
}
inline bool range_ok(Range const& range, Point& centroid)
{
std::size_t const n = boost::size(range);
if (n > 1)
{
return true;
}
else if (n <= 0)
{
#if defined(CENTROID_WITH_CATCH)
throw centroid_exception();
#endif
return false;
}
else // if (n == 1)
{
// Take over the first point in a "coordinate neutral way"
copy_coordinates(range.front(), centroid);
return false;
}
return true;
}