1 """

     2  This module houses the GEOS ctypes prototype functions for the 

     3  unary and binary predicate operations on geometries.

     4 """

     5 from ctypes import c_char, c_char_p, c_double

     6 from django.contrib.gis.geos.libgeos import lgeos, GEOM_PTR

     7 from django.contrib.gis.geos.prototypes.errcheck import check_predicate

     8 

     9 ## Binary & unary predicate functions ##

    10 def binary_predicate(func, *args):

    11     "For GEOS binary predicate functions."

    12     argtypes = [GEOM_PTR, GEOM_PTR]

    13     if args: argtypes += args

    14     func.argtypes = argtypes

    15     func.restype = c_char

    16     func.errcheck = check_predicate

    17     return func

    18 

    19 def unary_predicate(func):

    20     "For GEOS unary predicate functions."

    21     func.argtypes = [GEOM_PTR]

    22     func.restype = c_char

    23     func.errcheck = check_predicate

    24     return func

    25 

    26 ## Unary Predicates ##

    27 geos_hasz = unary_predicate(lgeos.GEOSHasZ)

    28 geos_isempty = unary_predicate(lgeos.GEOSisEmpty)

    29 geos_isring = unary_predicate(lgeos.GEOSisRing)

    30 geos_issimple = unary_predicate(lgeos.GEOSisSimple)

    31 geos_isvalid = unary_predicate(lgeos.GEOSisValid)

    32 

    33 ## Binary Predicates ##

    34 geos_contains = binary_predicate(lgeos.GEOSContains)

    35 geos_crosses = binary_predicate(lgeos.GEOSCrosses)

    36 geos_disjoint = binary_predicate(lgeos.GEOSDisjoint)

    37 geos_equals = binary_predicate(lgeos.GEOSEquals)

    38 geos_equalsexact = binary_predicate(lgeos.GEOSEqualsExact, c_double)

    39 geos_intersects = binary_predicate(lgeos.GEOSIntersects)

    40 geos_overlaps = binary_predicate(lgeos.GEOSOverlaps)

    41 geos_relatepattern = binary_predicate(lgeos.GEOSRelatePattern, c_char_p)

    42 geos_touches = binary_predicate(lgeos.GEOSTouches)

    43 geos_within = binary_predicate(lgeos.GEOSWithin)