backward_step_mesh.template.cc
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26#ifndef OOMPH_BACKWARD_STEP_MESH_TEMPLATE_HEADER
27#define OOMPH_BACKWARD_STEP_MESH_TEMPLATE_HEADER
28
29#ifndef OOMPH_BACKWARD_STEP_MESH_HEADER
30#error __FILE__ should only be included from backward_step_mesh.h.
31#endif // OOMPH_BACKWARD_STEP_MESH_HEADER
32
33#include <set>
34#include <map>
35
36namespace oomph
37{
38 //=================================================================
39 /// Actual build function. Pass overall number of elements in the
40 /// horizontal and vertical directions, nx and ny, and the corresponding
41 /// dimensions, lx and ly. nx_cut_out and ny_cut_out elements
42 /// are cut out from the lower right corner to create the
43 /// (reversed) backward step geometry. Timestepper defaults
44 /// to Steady.
45 //=================================================================
46 template<class ELEMENT>
47 void BackwardStepQuadMesh<ELEMENT>::build_mesh(const unsigned& nx,
48 const unsigned& ny,
49 const unsigned& nx_cut_out,
50 const unsigned& ny_cut_out,
51 const double& lx,
52 const double& ly)
53 {
54 // Mesh can only be built with 2D Qelements.
55 MeshChecker::assert_geometric_element<QElementGeometricBase, ELEMENT>(2);
56
57 // By default nobody's claiming any nodes
58 std::map<Node*, bool> keep;
59
60 // Get elements outside lower right block
61 Vector<FiniteElement*> el_retained_pt;
62 Vector<FiniteElement*> el_killed_pt;
63 for (unsigned i = 0; i < nx; i++)
64 {
65 for (unsigned j = 0; j < ny; j++)
66 {
67 FiniteElement* el_pt = this->finite_element_pt(i + nx * j);
68 if ((i > (nx_cut_out - 1)) && (j < ny_cut_out))
69 {
70 el_killed_pt.push_back(el_pt);
71 }
72 else
73 {
74 el_retained_pt.push_back(el_pt);
75 unsigned nnod_el = el_pt->nnode();
76 for (unsigned jj = 0; jj < nnod_el; jj++)
77 {
78 keep[el_pt->node_pt(jj)] = true;
79 }
80 }
81 }
82 }
83
84 // By default nobody's claiming the nodes; also store old
85 // boundary ids
86 std::map<Node*, std::set<unsigned>> boundaries;
87 unsigned nnod = this->nnode();
88 for (unsigned j = 0; j < nnod; j++)
89 {
90 std::set<unsigned>* aux_pt = 0;
91 this->node_pt(j)->get_boundaries_pt(aux_pt);
92 if (aux_pt != 0)
93 {
94 boundaries[this->node_pt(j)] = (*aux_pt);
95 }
96 }
97
98 // Remove information about boundary nodes
99 this->remove_boundary_nodes();
100
101 // Reset number of boundaries
102 this->set_nboundary(6);
103
104 // Kill superfluous nodes
105 Vector<Node*> node_backup_pt(this->Node_pt);
106 this->Node_pt.clear();
107 for (unsigned j = 0; j < nnod; j++)
108 {
109 Node* nod_pt = node_backup_pt[j];
110 if (keep[nod_pt])
111 {
112 this->Node_pt.push_back(nod_pt);
113 std::set<unsigned> aux = boundaries[nod_pt];
114 for (std::set<unsigned>::iterator it = boundaries[nod_pt].begin();
115 it != boundaries[nod_pt].end();
116 it++)
117 {
118 unsigned b = (*it);
119 if (b > 0) b += 2;
120 this->add_boundary_node(b, nod_pt);
121 }
122 }
123 else
124 {
125 delete node_backup_pt[j];
126 }
127 }
128
129 // Add nodes to new boundary 1
130 unsigned i = nx_cut_out - 1;
131 for (unsigned j = 0; j < ny_cut_out; j++)
132 {
133 FiniteElement* el_pt = this->finite_element_pt(i + nx * j);
134 unsigned nnod_1d = el_pt->nnode_1d();
135 for (unsigned jj = 0; jj < nnod_1d; jj++)
136 {
137 unsigned jnod = (nnod_1d - 1) + jj * nnod_1d;
138 if (!(el_pt->node_pt(jnod)->is_on_boundary()))
139 {
140 Node* nod_pt = el_pt->node_pt(jnod);
141 this->convert_to_boundary_node(nod_pt);
142 }
143 this->add_boundary_node(1, el_pt->node_pt(jnod));
144 }
145 }
146
147 // Add nodes to new boundary 2
148 unsigned j = ny_cut_out;
149 for (unsigned i = nx_cut_out; i < nx; i++)
150 {
151 FiniteElement* el_pt = this->finite_element_pt(i + nx * j);
152 unsigned nnod_1d = el_pt->nnode_1d();
153 for (unsigned jj = 0; jj < nnod_1d; jj++)
154 {
155 unsigned jnod = jj;
156 if (!(el_pt->node_pt(jnod)->is_on_boundary()))
157 {
158 Node* nod_pt = el_pt->node_pt(jnod);
159 this->convert_to_boundary_node(nod_pt);
160 }
161 this->add_boundary_node(2, el_pt->node_pt(jnod));
162 }
163 }
164
165 // Kill redundant elements
166 this->Element_pt.clear();
167 unsigned n_retained = el_retained_pt.size();
168 for (unsigned e = 0; e < n_retained; e++)
169 {
170 this->Element_pt.push_back(el_retained_pt[e]);
171 }
172 unsigned n_killed = el_killed_pt.size();
173 for (unsigned e = 0; e < n_killed; e++)
174 {
175 delete el_killed_pt[e];
176 }
177
178 // Re-setup lookup scheme that establishes which elements are located
179 // on the mesh boundaries
180 this->setup_boundary_element_info();
181 }
182
183} // namespace oomph
184
185#endif
oomph::BackwardStepQuadMesh::build_mesh
void build_mesh(const unsigned &nx, const unsigned &ny, const unsigned &nx_cut_out, const unsigned &ny_cut_out, const double &lx, const double &ly)
Actual build function.
Definition backward_step_mesh.template.cc:47