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Merge pull request #3846 from mapycz/interior-scale-invariant-v3.0.x

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v3.0.x: Interior, polylabel: Scale precision by polygon size
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Artem Pavlenko 2018-02-06 13:20:51 +01:00 committed by GitHub
commit 1bb070c842
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2 changed files with 13 additions and 17 deletions
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28
src/geometry/interior.cpp
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@ -153,15 +153,8 @@ struct cell
}; };
template <class T> template <class T>
boost::optional<point<T>> polylabel(polygon<T> const& polygon, T precision = 1) point<T> polylabel(polygon<T> const& polygon, box2d<T> const& bbox , T precision = 1)
{ {
if (polygon.exterior_ring.empty())
{
return boost::none;
}
// find the bounding box of the outer ring
const box2d<T> bbox = envelope(polygon.exterior_ring);
const point<T> size { bbox.width(), bbox.height() }; const point<T> size { bbox.width(), bbox.height() };
const T cell_size = std::min(size.x, size.y); const T cell_size = std::min(size.x, size.y);
@ -177,14 +170,14 @@ boost::optional<point<T>> polylabel(polygon<T> const& polygon, T precision = 1)
if (cell_size == 0) if (cell_size == 0)
{ {
return point<T>{ bbox.minx(), bbox.miny() }; return { bbox.minx(), bbox.miny() };
} }
point<T> centroid; point<T> centroid;
if (!mapnik::geometry::centroid(polygon, centroid)) if (!mapnik::geometry::centroid(polygon, centroid))
{ {
auto center = bbox.center(); auto center = bbox.center();
return point<T>{ center.x, center.y }; return { center.x, center.y };
} }
fitness_functor<T> fitness_func(centroid, size); fitness_functor<T> fitness_func(centroid, size);
@ -232,15 +225,18 @@ boost::optional<point<T>> polylabel(polygon<T> const& polygon, T precision = 1)
template <class T> template <class T>
bool interior(polygon<T> const& polygon, double scale_factor, point<T> & pt) bool interior(polygon<T> const& polygon, double scale_factor, point<T> & pt)
{ {
// This precision has been chosen to work well in the map (viewport) coordinates. if (polygon.exterior_ring.empty())
double precision = 10.0 * scale_factor;
if (boost::optional<point<T>> opt = detail::polylabel(polygon, precision))
{ {
pt = *opt; return false;
return true;
} }
return false; const box2d<T> bbox = envelope(polygon.exterior_ring);
// Let the precision be 1% of the polygon size to be independent to map scale.
double precision = (std::max(bbox.width(), bbox.height()) / 100.0) * scale_factor;
pt = detail::polylabel(polygon, bbox, precision);
return true;
} }
template template

2
test/data-visual

@ -1 +1 @@
Subproject commit 1a9784770b378d5bdc05020b5f27d79189c7af4a Subproject commit 758c44874adcc54702b3f4d9ff5cdff64e967b2b