"""
Provides a wrapper for the shapely.lib C API for use in Cython.
Internally, the shapely C extension uses a PyCapsule to provide run-time access
to function pointers within the C API.
To use these functions, you must first call the following function in each Cython module:
`import_shapely_c_api()`
This uses a macro to dynamically load the functions from pointers in the PyCapsule.
Each C function in shapely.lib exposed in the C API must be specially-wrapped to enable
this capability.
Segfaults will occur if the C API is not imported properly.
"""
cimport numpy as np
from cpython.ref cimport PyObject
from shapely._geos cimport GEOSContextHandle_t, GEOSCoordSequence, GEOSGeometry
cdef extern from "c_api.h":
cdef enum ShapelyErrorCode:
PGERR_SUCCESS,
PGERR_NOT_A_GEOMETRY,
PGERR_GEOS_EXCEPTION,
PGERR_NO_MALLOC,
PGERR_GEOMETRY_TYPE,
PGERR_MULTIPOINT_WITH_POINT_EMPTY,
PGERR_COORD_OUT_OF_BOUNDS,
PGERR_EMPTY_GEOMETRY,
PGERR_GEOJSON_EMPTY_POINT,
PGERR_LINEARRING_NCOORDS,
PGERR_NAN_COORD,
PGWARN_INVALID_WKB,
PGWARN_INVALID_WKT,
PGWARN_INVALID_GEOJSON,
PGERR_PYSIGNAL
cpdef enum ShapelyHandleNan:
SHAPELY_HANDLE_NAN_ALLOW,
SHAPELY_HANDLE_NAN_SKIP,
SHAPELY_HANDLE_NANS_ERROR
# shapely.lib C API loader; returns -1 on error
# MUST be called before calling other C API functions
int import_shapely_c_api() except -1
# C functions provided by the shapely.lib C API
# Note: GeometryObjects are always managed as Python objects
# in Cython to avoid memory leaks, not PyObject* (even though
# they are declared that way in the header file).
object PyGEOS_CreateGeometry(GEOSGeometry *ptr, GEOSContextHandle_t ctx)
char PyGEOS_GetGEOSGeometry(PyObject *obj, GEOSGeometry **out) nogil
int PyGEOS_CoordSeq_FromBuffer(
GEOSContextHandle_t ctx, const double* buf, unsigned int size,
unsigned int dims, char is_ring, int handle_nan,
GEOSCoordSequence** coord_seq) nogil