Geos ccw analysis

ext/geos_c_impl/analysis.c

@@ -24,9 +24,11 @@ RGEO_BEGIN_C
  */
 VALUE rgeo_geos_analysis_ccw_p(VALUE self, VALUE ring)
 {
+  char is_ccw = 0;
+  #ifdef RGEO_GEOS_SUPPORTS_ISCCW
+
   const RGeo_GeometryData* ring_data;
   const GEOSCoordSequence* coord_seq;
-  char is_ccw;
 
   rgeo_check_geos_object(ring);
 
@@ -37,17 +39,28 @@ VALUE rgeo_geos_analysis_ccw_p(VALUE self, VALUE ring)
   if (!GEOSCoordSeq_isCCW_r(ring_data->geos_context, coord_seq, &is_ccw)) {
     rb_raise(geos_error, "Could not determine if the CoordSeq is CCW.");
   }
+  #endif // RGEO_GEOS_SUPPORTS_ISCCW
 
   return is_ccw ? Qtrue : Qfalse;
 };
 
+static VALUE rgeo_geos_analysis_supports_ccw(VALUE self)
+{
+  #ifdef RGEO_GEOS_SUPPORTS_ISCCW
+    return Qtrue;
+  #else
+    return Qfalse;
+  #endif
+}
+
 
 void rgeo_init_geos_analysis(RGeo_Globals* globals)
 {
   VALUE geos_analysis_module;
 
   geos_analysis_module = rb_define_module_under(globals->geos_module, "Analysis");
   rb_define_singleton_method(geos_analysis_module, "ccw?", rgeo_geos_analysis_ccw_p, 1);
+  rb_define_singleton_method(geos_analysis_module, "ccw_supported?", rgeo_geos_analysis_supports_ccw, 0);
 }
 
 RGEO_END_C

ext/geos_c_impl/errors.c

@@ -12,7 +12,7 @@
 
 RGEO_BEGIN_C
 
-// Anay error relative to RGeo.
+// Any error relative to RGeo.
 VALUE rgeo_error;
 // RGeo error specific to the GEOS implementation.
 VALUE geos_error;

ext/geos_c_impl/errors.h

@@ -8,7 +8,7 @@
 
 RGEO_BEGIN_C
 
-// Anay error relative to RGeo.
+// Any error relative to RGeo.
 extern VALUE rgeo_error;
 // RGeo error specific to the GEOS implementation.
 extern VALUE geos_error;

ext/geos_c_impl/extconf.rb

@@ -31,6 +31,7 @@ def create_dummy_makefile
     have_func("GEOSPreparedContains_r", "geos_c.h")
     have_func("GEOSPreparedDisjoint_r", "geos_c.h")
     have_func("GEOSUnaryUnion_r", "geos_c.h")
+    have_func("GEOSCoordSeq_isCCW_r", "geos_c.h")
     have_func("rb_memhash", "ruby.h")
   end
 

ext/geos_c_impl/preface.h

@@ -21,6 +21,9 @@
 #ifdef HAVE_GEOSUNARYUNION_R
 #define RGEO_GEOS_SUPPORTS_UNARYUNION
 #endif
+#ifdef HAVE_GEOSCOORDSEQ_ISCCW_R
+#define RGEO_GEOS_SUPPORTS_ISCCW
+#endif
 #ifdef HAVE_RB_MEMHASH
 #define RGEO_SUPPORTS_NEW_HASHING
 #endif

lib/rgeo/cartesian/analysis.rb

@@ -19,7 +19,7 @@ class << self
         # If the factory used is GEOS based, use the GEOS implementation to
         # check that. Otherwise, this methods falls back to `ring_direction`.
         def ccw?(ring)
-          if RGeo::Geos.is_capi_geos?(ring)
+          if RGeo::Geos.is_capi_geos?(ring) && RGeo::Geos::Analysis.ccw_supported?
             RGeo::Geos::Analysis.ccw?(ring)
           else
             RGeo::Cartesian::Analysis.ring_direction(ring) == 1

test/cartesian_analysis_test.rb

@@ -79,14 +79,11 @@ def counterclockwise_near_circle
 
   def setup
     @fixtures = Fixtures.new(RGeo::Cartesian.simple_factory)
-    @cfixtures = Fixtures.new(RGeo::Geos.factory) if RGeo::Geos.supported?
   end
 
   # --------------------------------------------- RGeo::Cartesian::Analysis.ccw?
 
   def test_ccw_p_clockwise_triangle
-    ring = @cfixtures.clockwise_triangle
-    assert_equal(false, RGeo::Cartesian::Analysis.ccw?(ring))
     ring = @fixtures.clockwise_triangle
     assert_equal(
       false,
@@ -96,8 +93,6 @@ def test_ccw_p_clockwise_triangle
   end
 
   def test_ccw_p_counterclockwise_triangle
-    ring = @cfixtures.counterclockwise_triangle
-    assert_equal(true, RGeo::Cartesian::Analysis.ccw?(ring))
     ring = @fixtures.counterclockwise_triangle
     assert_equal(
       true,
@@ -107,27 +102,27 @@ def test_ccw_p_counterclockwise_triangle
   end
 
   def test_ccw_p_clockwise_puckered_quad
-    ring = @cfixtures.clockwise_puckered_quad
+    ring = @fixtures.clockwise_puckered_quad
     assert_equal(false, RGeo::Cartesian::Analysis.ccw?(ring))
   end
 
   def test_ccw_p_counterclockwise_puckered_quad
-    ring = @cfixtures.counterclockwise_puckered_quad
+    ring = @fixtures.counterclockwise_puckered_quad
     assert_equal(true, RGeo::Cartesian::Analysis.ccw?(ring))
   end
 
   def test_ccw_p_clockwise_hat
-    ring = @cfixtures.clockwise_hat
+    ring = @fixtures.clockwise_hat
     assert_equal(false, RGeo::Cartesian::Analysis.ccw?(ring))
   end
 
   def test_ccw_p_counterclockwise_hat
-    ring = @cfixtures.counterclockwise_hat
+    ring = @fixtures.counterclockwise_hat
     assert_equal(true, RGeo::Cartesian::Analysis.ccw?(ring))
   end
 
   def test_ccw_p_counterclockwise_near_circle
-    ring = @cfixtures.counterclockwise_near_circle
+    ring = @fixtures.counterclockwise_near_circle
     assert_equal(true, RGeo::Cartesian::Analysis.ccw?(ring))
   end
 

test/geos_capi/analysis_test.rb

@@ -3,12 +3,14 @@
 require_relative "../test_helper"
 
 module GeosCapi
-  class AnalysisTest < Minitest::Test
+  class AnalysisTest < CartesianAnalysisTest
     def setup
       skip "Needs GEOS." unless RGeo::Geos.capi_supported?
+      @fixtures = Fixtures.new(RGeo::Geos.factory)
     end
 
     def test_ccw_p_raises_if_not_a_geos_object
+      skip "Needs GEOS 3.7+" unless RGeo::Geos::Analysis.ccw_supported?
       factory = RGeo::Cartesian.simple_factory
       pt1 = factory.point(1, 0)
       pt2 = factory.point(2, 0)
@@ -18,12 +20,14 @@ def test_ccw_p_raises_if_not_a_geos_object
     end
 
     def test_ccw_p_raises_if_no_coordseq
+      skip "Needs GEOS 3.7+" unless RGeo::Geos::Analysis.ccw_supported?
       factory = RGeo::Geos.factory(native_interface: :capi)
       point = factory.point(1, 2)
       assert_raises(RGeo::Error::GeosError) { RGeo::Geos::Analysis.ccw?(point) }
     end
 
     def test_ccw_p_returns_true_if_ccw
+      skip "Needs GEOS 3.7+" unless RGeo::Geos::Analysis.ccw_supported?
       factory = RGeo::Geos.factory(native_interface: :capi)
       pt1 = factory.point(1, 0)
       pt2 = factory.point(2, 0)
@@ -34,5 +38,14 @@ def test_ccw_p_returns_true_if_ccw
       assert_equal(false, RGeo::Geos::Analysis.ccw?(ring_cw))
       assert_equal(true, RGeo::Geos::Analysis.ccw?(ring_ccw))
     end
+
+    # no need to re-test the ruby implementation
+    undef :test_ring_direction_clockwise_triangle
+    undef :test_ring_direction_counterclockwise_triangle
+    undef :test_ring_direction_clockwise_puckered_quad
+    undef :test_ring_direction_counterclockwise_puckered_quad
+    undef :test_ring_direction_clockwise_hat
+    undef :test_ring_direction_counterclockwise_hat
+    undef :test_ring_direction_counterclockwise_near_circle
   end
 end