| from ctypes import c_char_p, c_int, c_void_p, POINTER |
| from django.contrib.gis.gdal.libgdal import lgdal, std_call |
| from django.contrib.gis.gdal.prototypes.generation import \ |
| const_string_output, double_output, int_output, \ |
| srs_output, string_output, void_output |
| |
| ## Shortcut generation for routines with known parameters. |
| def srs_double(f): |
| """ |
| Creates a function prototype for the OSR routines that take |
| the OSRSpatialReference object and |
| """ |
| return double_output(f, [c_void_p, POINTER(c_int)], errcheck=True) |
| |
| def units_func(f): |
| """ |
| Creates a ctypes function prototype for OSR units functions, e.g., |
| OSRGetAngularUnits, OSRGetLinearUnits. |
| """ |
| return double_output(f, [c_void_p, POINTER(c_char_p)], strarg=True) |
| |
| # Creation & destruction. |
| clone_srs = srs_output(std_call('OSRClone'), [c_void_p]) |
| new_srs = srs_output(std_call('OSRNewSpatialReference'), [c_char_p]) |
| release_srs = void_output(lgdal.OSRRelease, [c_void_p], errcheck=False) |
| destroy_srs = void_output(std_call('OSRDestroySpatialReference'), [c_void_p], errcheck=False) |
| srs_validate = void_output(lgdal.OSRValidate, [c_void_p]) |
| |
| # Getting the semi_major, semi_minor, and flattening functions. |
| semi_major = srs_double(lgdal.OSRGetSemiMajor) |
| semi_minor = srs_double(lgdal.OSRGetSemiMinor) |
| invflattening = srs_double(lgdal.OSRGetInvFlattening) |
| |
| # WKT, PROJ, EPSG, XML importation routines. |
| from_wkt = void_output(lgdal.OSRImportFromWkt, [c_void_p, POINTER(c_char_p)]) |
| from_proj = void_output(lgdal.OSRImportFromProj4, [c_void_p, c_char_p]) |
| from_epsg = void_output(std_call('OSRImportFromEPSG'), [c_void_p, c_int]) |
| from_xml = void_output(lgdal.OSRImportFromXML, [c_void_p, c_char_p]) |
| |
| # Morphing to/from ESRI WKT. |
| morph_to_esri = void_output(lgdal.OSRMorphToESRI, [c_void_p]) |
| morph_from_esri = void_output(lgdal.OSRMorphFromESRI, [c_void_p]) |
| |
| # Identifying the EPSG |
| identify_epsg = void_output(lgdal.OSRAutoIdentifyEPSG, [c_void_p]) |
| |
| # Getting the angular_units, linear_units functions |
| linear_units = units_func(lgdal.OSRGetLinearUnits) |
| angular_units = units_func(lgdal.OSRGetAngularUnits) |
| |
| # For exporting to WKT, PROJ.4, "Pretty" WKT, and XML. |
| to_wkt = string_output(std_call('OSRExportToWkt'), [c_void_p, POINTER(c_char_p)]) |
| to_proj = string_output(std_call('OSRExportToProj4'), [c_void_p, POINTER(c_char_p)]) |
| to_pretty_wkt = string_output(std_call('OSRExportToPrettyWkt'), [c_void_p, POINTER(c_char_p), c_int], offset=-2) |
| |
| # Memory leak fixed in GDAL 1.5; still exists in 1.4. |
| to_xml = string_output(lgdal.OSRExportToXML, [c_void_p, POINTER(c_char_p), c_char_p], offset=-2) |
| |
| # String attribute retrival routines. |
| get_attr_value = const_string_output(std_call('OSRGetAttrValue'), [c_void_p, c_char_p, c_int]) |
| get_auth_name = const_string_output(lgdal.OSRGetAuthorityName, [c_void_p, c_char_p]) |
| get_auth_code = const_string_output(lgdal.OSRGetAuthorityCode, [c_void_p, c_char_p]) |
| |
| # SRS Properties |
| isgeographic = int_output(lgdal.OSRIsGeographic, [c_void_p]) |
| islocal = int_output(lgdal.OSRIsLocal, [c_void_p]) |
| isprojected = int_output(lgdal.OSRIsProjected, [c_void_p]) |
| |
| # Coordinate transformation |
| new_ct= srs_output(std_call('OCTNewCoordinateTransformation'), [c_void_p, c_void_p]) |
| destroy_ct = void_output(std_call('OCTDestroyCoordinateTransformation'), [c_void_p], errcheck=False) |