Add projection keyword to from_geoarrow + update type hints (#78)

src/geoarrow.cpp

@@ -15,6 +15,7 @@ py::array_t<PyObjectGeography> from_geoarrow(py::object input,
                                              bool oriented,
                                              bool planar,
                                              float tessellate_tolerance,
+                                             Projection projection,
                                              py::object geometry_encoding) {
     if (!py::hasattr(input, "__arrow_c_array__")) {
         throw std::invalid_argument(
@@ -33,6 +34,7 @@ py::array_t<PyObjectGeography> from_geoarrow(py::object input,
 
     s2geog::geoarrow::ImportOptions options;
     options.set_oriented(oriented);
+    options.set_projection(projection.s2_projection());
     if (planar) {
         auto tol = S1Angle::Radians(tessellate_tolerance / EARTH_RADIUS_METERS);
         options.set_tessellate_tolerance(tol);
@@ -264,6 +266,7 @@ void init_geoarrow(py::module& m) {
           py::arg("oriented") = false,
           py::arg("planar") = false,
           py::arg("tessellate_tolerance") = 100.0,
+          py::arg("projection") = Projection::lnglat(),
           py::arg("geometry_encoding") = py::none(),
           R"pbdoc(
         Create an array of geographies from an Arrow array object with a GeoArrow
@@ -301,6 +304,10 @@ void init_geoarrow(py::module& m) {
             The maximum distance in meters that a point must be moved to
             satisfy the planar edge constraint. This is only used if `planar`
             is set to True.
+        projection : spherely.Projection, default Projection.lnglat()
+            The projection of the input coordinates. By default, it assumes
+            longitude/latitude coordinates, but this option allows to convert
+            from coordinates in pseudo-mercator or orthographic projection as well.
         geometry_encoding : str, default None
             By default, the encoding is inferred from the GeoArrow extension
             type of the input array.

src/spherely.pyi

@@ -60,6 +60,16 @@ MultiLineStringGeography = Annotated[Geography, GeographyType.MULTILINESTRING]
 MultiPolygonGeography = Annotated[Geography, GeographyType.MULTIPOLYGON]
 GeometryCollection = Annotated[Geography, GeographyType.GEOMETRYCOLLECTION]
 
+# Projection class
+
+class Projection:
+    @staticmethod
+    def lnglat() -> Projection: ...
+    @staticmethod
+    def speudo_mercator() -> Projection: ...
+    @staticmethod
+    def orthographic(longitude: float, latitude: float) -> Projection: ...
+
 # Numpy-like vectorized (universal) functions
 
 _NameType = TypeVar("_NameType", bound=str)
@@ -222,17 +232,31 @@ def from_wkb(
     tessellate_tolerance: float = 100.0,
 ) -> npt.NDArray[Any]: ...
 
+class ArrowSchemaExportable(Protocol):
+    def __arrow_c_schema__(self) -> object: ...
+
 class ArrowArrayExportable(Protocol):
     def __arrow_c_array__(
         self, requested_schema: object | None = None
     ) -> Tuple[object, object]: ...
 
+def to_geoarrow(
+    input: npt.ArrayLike,
+    /,
+    *,
+    output_schema: ArrowSchemaExportable | None = None,
+    projection: Projection = Projection.lnglat(),
+    planar: bool = False,
+    tessellate_tolerance: float = 100.0,
+    precision: int = 6,
+) -> ArrowArrayExportable: ...
 def from_geoarrow(
     input: ArrowArrayExportable,
     /,
     *,
     oriented: bool = False,
     planar: bool = False,
     tessellate_tolerance: float = 100.0,
+    projection: Projection = Projection.lnglat(),
     geometry_encoding: str | None = None,
 ) -> npt.NDArray[Any]: ...

tests/test_geoarrow.py

@@ -92,6 +92,18 @@ def test_from_wkt_planar():
     assert spherely.distance(result, spherely.point(-30.1, 45)) < 10
 
 
+def test_from_geoarrow_projection():
+    arr = ga.as_wkt(["POINT (1 0)", "POINT(0 1)"])
+
+    result = spherely.from_geoarrow(
+        arr, projection=spherely.Projection.orthographic(0, 0)
+    )
+    expected = spherely.points([90, 0], [0, 90])
+    # TODO use equality when we support precision / snapping
+    # assert spherely.equals(result, expected).all()
+    assert (spherely.to_wkt(result) == spherely.to_wkt(expected)).all()
+
+
 def test_from_geoarrow_no_extension_type():
     arr = pa.array(["POINT (1 1)", "POINT(2 2)", "POINT(3 3)"])