diff options
| -rw-r--r-- | include/mbgl/util/geo.hpp | 8 | ||||
| -rw-r--r-- | src/mbgl/util/geo.cpp | 19 | ||||
| -rw-r--r-- | test/miscellaneous/geo.cpp | 61 | ||||
| -rw-r--r-- | test/test.gypi | 1 |
4 files changed, 89 insertions, 0 deletions
diff --git a/include/mbgl/util/geo.hpp b/include/mbgl/util/geo.hpp index 6ece6d4de9..ff13726803 100644 --- a/include/mbgl/util/geo.hpp +++ b/include/mbgl/util/geo.hpp @@ -3,12 +3,17 @@ namespace mbgl { +class TileID; + struct LatLng { double latitude = 0; double longitude = 0; inline LatLng(double lat = 0, double lon = 0) : latitude(lat), longitude(lon) {} + + // Constructs a LatLng object with the top left position of the specified tile. + LatLng(const TileID& id); }; struct ProjectedMeters { @@ -26,6 +31,9 @@ struct LatLngBounds { inline LatLngBounds(LatLng sw_ = {90, 180}, LatLng ne_ = {-90, -180}) : sw(sw_), ne(ne_) {} + // Constructs a LatLngBounds object with the tile's exact boundaries. + LatLngBounds(const TileID& id); + inline void extend(const LatLng& point) { if (point.latitude < sw.latitude) sw.latitude = point.latitude; if (point.latitude > ne.latitude) ne.latitude = point.latitude; diff --git a/src/mbgl/util/geo.cpp b/src/mbgl/util/geo.cpp new file mode 100644 index 0000000000..b08b10d1e6 --- /dev/null +++ b/src/mbgl/util/geo.cpp @@ -0,0 +1,19 @@ +#include <mbgl/util/geo.hpp> +#include <mbgl/map/tile_id.hpp> + +#include <cmath> + +namespace mbgl { + +LatLng::LatLng(const TileID& id) { + latitude = id.x / std::pow(2.0, id.z) * 360.0 - 180; + const double n = M_PI - 2.0 * M_PI * id.y / std::pow(2.0, id.z); + longitude = 180.0 / M_PI * std::atan(0.5 * (std::exp(n) - std::exp(-n))); +} + +LatLngBounds::LatLngBounds(const TileID& id) + : sw(TileID{ id.z, id.x, id.y + 1, id.sourceZ }), + ne(TileID{ id.z, id.x + 1, id.y, id.sourceZ }) { +} + +} // end namespace mbgl diff --git a/test/miscellaneous/geo.cpp b/test/miscellaneous/geo.cpp new file mode 100644 index 0000000000..093ea7040c --- /dev/null +++ b/test/miscellaneous/geo.cpp @@ -0,0 +1,61 @@ +#include "../fixtures/util.hpp" + +#include <mbgl/util/geo.hpp> +#include <mbgl/map/tile_id.hpp> + +using namespace mbgl; + +TEST(Geo, LatLngFromTileID) { + for (int i = 0; i < 20; i++) { + const LatLng ll{ TileID(i, 0, 0, 0) }; + ASSERT_DOUBLE_EQ(-180, ll.latitude); + ASSERT_DOUBLE_EQ(85.051128779806604, ll.longitude); + } + + { + const LatLng ll{ TileID(0, 1, 0, 0) }; + ASSERT_DOUBLE_EQ(180, ll.latitude); + ASSERT_DOUBLE_EQ(85.051128779806604, ll.longitude); + } + + { + const LatLng ll{ TileID(0, -1, 0, 0) }; + ASSERT_DOUBLE_EQ(-540, ll.latitude); + ASSERT_DOUBLE_EQ(85.051128779806604, ll.longitude); + } +} + + +TEST(Geo, LatLngBoundsFromTileID) { + { + const LatLngBounds bounds{ TileID(0, 0, 0, 0) }; + ASSERT_DOUBLE_EQ(-180, bounds.sw.latitude); + ASSERT_DOUBLE_EQ(-85.051128779806604, bounds.sw.longitude); + ASSERT_DOUBLE_EQ(180, bounds.ne.latitude); + ASSERT_DOUBLE_EQ(85.051128779806604, bounds.ne.longitude); + } + + { + const LatLngBounds bounds{ TileID(1, 0, 1, 0) }; + ASSERT_DOUBLE_EQ(-180, bounds.sw.latitude); + ASSERT_DOUBLE_EQ(-85.051128779806604, bounds.sw.longitude); + ASSERT_DOUBLE_EQ(0, bounds.ne.latitude); + ASSERT_DOUBLE_EQ(0, bounds.ne.longitude); + } + + { + const LatLngBounds bounds{ TileID(1, 1, 1, 0) }; + ASSERT_DOUBLE_EQ(0, bounds.sw.latitude); + ASSERT_DOUBLE_EQ(-85.051128779806604, bounds.sw.longitude); + ASSERT_DOUBLE_EQ(180, bounds.ne.latitude); + ASSERT_DOUBLE_EQ(0, bounds.ne.longitude); + } + + { + const LatLngBounds bounds{ TileID(1, 0, 0, 0) }; + ASSERT_DOUBLE_EQ(-180, bounds.sw.latitude); + ASSERT_DOUBLE_EQ(0, bounds.sw.longitude); + ASSERT_DOUBLE_EQ(0, bounds.ne.latitude); + ASSERT_DOUBLE_EQ(85.051128779806604, bounds.ne.longitude); + } +} diff --git a/test/test.gypi b/test/test.gypi index f2407f5058..42dc04448a 100644 --- a/test/test.gypi +++ b/test/test.gypi @@ -46,6 +46,7 @@ 'miscellaneous/comparisons.cpp', 'miscellaneous/enums.cpp', 'miscellaneous/functions.cpp', + 'miscellaneous/geo.cpp', 'miscellaneous/map.cpp', 'miscellaneous/map_context.cpp', 'miscellaneous/mapbox.cpp', |