Chaste  Release::3.4
ToroidalHoneycombVertexMeshGenerator.cpp
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34 */
35 
36 #include "ToroidalHoneycombVertexMeshGenerator.hpp"
37 
39  unsigned numElementsUp,
40  double cellRearrangementThreshold,
41  double t2Threshold)
42 {
43  // numElementsAcross and numElementsUp must be even for toroidal meshes
44  assert(numElementsAcross > 1);
45  assert(numElementsUp > 1);
46  assert(numElementsAcross%2 == 0);
47  assert(numElementsUp%2 == 0);
48 
49  assert(cellRearrangementThreshold > 0.0);
50  assert(t2Threshold > 0.0);
51 
52  std::vector<Node<2>*> nodes;
53  std::vector<VertexElement<2,2>*> elements;
54 
55  unsigned node_index = 0;
56  unsigned node_indices[6];
57  unsigned element_index;
58 
59  // Create the nodes
60  for (unsigned j=0; j<2*numElementsUp; j++)
61  {
62  for (unsigned i=0; i<numElementsAcross; i++)
63  {
64  double x_coord = ((j%4 == 0)||(j%4 == 3)) ? i+0.5 : i;
65  double y_coord = (1.5*j - 0.5*(j%2))*0.5/sqrt(3.0);
66 
67  Node<2>* p_node = new Node<2>(node_index, false , x_coord, y_coord);
68  nodes.push_back(p_node);
69  node_index++;
70  }
71  }
72 
73  /*
74  * Create the elements. The array node_indices contains the
75  * global node indices from bottom, going anticlockwise.
76  */
77  for (unsigned j=0; j<numElementsUp; j++)
78  {
79  for (unsigned i=0; i<numElementsAcross; i++)
80  {
81  element_index = j*numElementsAcross + i;
82 
83  node_indices[0] = 2*j*numElementsAcross + i + 1*(j%2==1);
84  node_indices[1] = node_indices[0] + numElementsAcross + 1*(j%2==0);
85  node_indices[2] = node_indices[0] + 2*numElementsAcross + 1*(j%2==0);
86  node_indices[3] = node_indices[0] + 3*numElementsAcross;
87  node_indices[4] = node_indices[0] + 2*numElementsAcross - 1*(j%2==1);
88  node_indices[5] = node_indices[0] + numElementsAcross - 1*(j%2==1);
89 
90  if (i == numElementsAcross-1) // on far right
91  {
92  node_indices[0] -= numElementsAcross*(j%2==1);
93  node_indices[1] -= numElementsAcross;
94  node_indices[2] -= numElementsAcross;
95  node_indices[3] -= numElementsAcross*(j%2==1);
96  }
97  if (j == numElementsUp-1) // on far top
98  {
99  node_indices[2] -= 2*numElementsAcross*numElementsUp;
100  node_indices[3] -= 2*numElementsAcross*numElementsUp;
101  node_indices[4] -= 2*numElementsAcross*numElementsUp;
102  }
103 
104  std::vector<Node<2>*> element_nodes;
105  for (unsigned k=0; k<6; k++)
106  {
107  element_nodes.push_back(nodes[node_indices[k]]);
108  }
109  VertexElement<2,2>* p_element = new VertexElement<2,2>(element_index, element_nodes);
110  elements.push_back(p_element);
111  }
112  }
113 
114  double mesh_width = numElementsAcross;
115  double mesh_height = 1.5*numElementsUp/sqrt(3.0);
116 
117  mpMesh = new Toroidal2dVertexMesh(mesh_width, mesh_height, nodes, elements, cellRearrangementThreshold, t2Threshold);
118 }
119 
121 {
122  EXCEPTION("A toroidal mesh was created but a normal mesh is being requested.");
123  return mpMesh; // Not really
124 }
125 
127 {
128  return (Toroidal2dVertexMesh*) mpMesh;
129 }
Definition: Node.hpp:58
#define EXCEPTION(message)
Definition: Exception.hpp:143
ToroidalHoneycombVertexMeshGenerator(unsigned numElementsAcross, unsigned numElementsUp, double cellRearrangementThreshold=0.01, double t2Threshold=0.001)