Unit tests for "tangent" ray/hole intersection

tests/mesh/mesh_triangulation.C

@@ -54,8 +54,9 @@ public:
  // This covers an old poly2tri collinearity-tolerance bug
  CPPUNIT_TEST( testPoly2TriHolesExtraRefined );
 
- // This covers a more recent tolerance bug when verifying holes
+ // These cover more recent tolerance issues when verifying holes
  CPPUNIT_TEST( testPoly2TriHolePerturbed );
+ CPPUNIT_TEST( testPoly2TriHoleTangentPerturbed );
 
  CPPUNIT_TEST( testPoly2TriNonUniformRefined );
  CPPUNIT_TEST( testPoly2TriHolesNonUniformRefined );
@@ -68,6 +69,7 @@ public:
  CPPUNIT_TEST( testTriangleInterp2 );
  CPPUNIT_TEST( testTriangleHoles );
  CPPUNIT_TEST( testTriangleHolePerturbed );
+ CPPUNIT_TEST( testTriangleHoleTangentPerturbed );
  CPPUNIT_TEST( testTriangleMeshedHoles );
  CPPUNIT_TEST( testTriangleEdges );
  CPPUNIT_TEST( testTriangleSegments );
@@ -517,6 +519,65 @@ public:
  }
 
 
+ void testTriangulatorHoleTangentPerturbed(MeshBase & mesh,
+ TriangulatorInterface & triangulator)
+ {
+ // Points based on a simplification of a hole verification failure
+ // case
+ mesh.add_point(Point(200,0), 0);
+ mesh.add_point(Point(200,100), 1);
+ mesh.add_point(Point(100,100), 2);
+ mesh.add_point(Point(0,100), 3);
+ mesh.add_point(Point(-100,100), 4);
+ mesh.add_point(Point(-200,100), 5);
+ mesh.add_point(Point(-200,0), 6);
+ mesh.add_point(Point(-200,-100), 7);
+ mesh.add_point(Point(-100,-100), 8);
+ mesh.add_point(Point(0,-100), 9);
+ mesh.add_point(Point(100,-100), 10);
+ mesh.add_point(Point(200,-100), 11);
+
+ commonSettings(triangulator);
+
+ // Two diamond holes, in *almost* the center of each half of that
+ // rectangle
+ TriangulatorInterface::PolygonHole
+ left_diamond(Point(-100,4.e-16),
+ std::sqrt(2)/2, 4),
+ right_diamond(Point(100,-4.e-16),
+ std::sqrt(2)/2, 4);
+ const std::vector<TriangulatorInterface::Hole*> holes
+ { &left_diamond, &right_diamond };
+ triangulator.attach_hole_list(&holes);
+
+ triangulator.triangulate();
+
+ CPPUNIT_ASSERT_EQUAL(mesh.n_elem(), dof_id_type(22));
+
+ // Center coordinates for all the elements we expect
+ const Real r2p200o6 = (std::sqrt(Real(2))+200)/6,
+ r2p400o6 = (std::sqrt(Real(2))+400)/6;
+
+ std::vector <Point> expected_centers
+ { {50+r2p400o6,100./3},
+ {50+r2p400o6,-100./3},
+ {50+100./3,r2p400o6}, {50-100./3,r2p400o6},
+ {50+100./3,-r2p400o6}, {50-100./3,-r2p400o6},
+ {50+r2p200o6,r2p200o6}, {50-r2p200o6,r2p200o6},
+ {50+r2p200o6,-r2p200o6}, {50-r2p200o6,-r2p200o6},
+ {50-r2p400o6,100./3},
+ {50-r2p400o6,-100./3},
+ {-50+100./3,r2p400o6}, {50-100./3,r2p400o6},
+ {-50+100./3,-r2p400o6}, {50-100./3,-r2p400o6},
+ {-50+r2p200o6,r2p200o6}, {50-r2p200o6,r2p200o6},
+ {-50+r2p200o6,-r2p200o6}, {50-r2p200o6,-r2p200o6},
+ {0,100./3}, {0,-100./3}
+ };
+
+ testFoundCenters(mesh, expected_centers);
+ }
+
+
  void testTriangulatorMeshedHoles(MeshBase & mesh,
  TriangulatorInterface & triangulator)
  {
@@ -710,6 +771,16 @@ public:
  }
 
 
+ void testTriangleHoleTangentPerturbed()
+ {
+ LOG_UNIT_TEST;
+
+ Mesh mesh(*TestCommWorld);
+ TriangleInterface triangle(mesh);
+ testTriangulatorHoleTangentPerturbed(mesh, triangle);
+ }
+
+
  void testTriangleMeshedHoles()
  {
  LOG_UNIT_TEST;
@@ -804,6 +875,16 @@ public:
  }
 
 
+ void testPoly2TriHoleTangentPerturbed()
+ {
+ LOG_UNIT_TEST;
+
+ Mesh mesh(*TestCommWorld);
+ Poly2TriTriangulator p2t_tri(mesh);
+ testTriangulatorHoleTangentPerturbed(mesh, p2t_tri);
+ }
+
+
  void testPoly2TriMeshedHoles()
  {
  LOG_UNIT_TEST;