1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
#include "btReducedDeformableBodyHelpers.h"
#include "../btSoftBodyHelpers.h"
#include <iostream>
#include <string>
#include <sstream>
btReducedDeformableBody* btReducedDeformableBodyHelpers::createReducedDeformableObject(btSoftBodyWorldInfo& worldInfo, const std::string& file_path, const std::string& vtk_file, const int num_modes, bool rigid_only) {
std::string filename = file_path + vtk_file;
btReducedDeformableBody* rsb = btReducedDeformableBodyHelpers::createFromVtkFile(worldInfo, filename.c_str());
rsb->setReducedModes(num_modes, rsb->m_nodes.size());
btReducedDeformableBodyHelpers::readReducedDeformableInfoFromFiles(rsb, file_path.c_str());
rsb->disableReducedModes(rigid_only);
return rsb;
}
btReducedDeformableBody* btReducedDeformableBodyHelpers::createFromVtkFile(btSoftBodyWorldInfo& worldInfo, const char* vtk_file)
{
std::ifstream fs;
fs.open(vtk_file);
btAssert(fs);
typedef btAlignedObjectArray<int> Index;
std::string line;
btAlignedObjectArray<btVector3> X;
btVector3 position;
btAlignedObjectArray<Index> indices;
bool reading_points = false;
bool reading_tets = false;
size_t n_points = 0;
size_t n_tets = 0;
size_t x_count = 0;
size_t indices_count = 0;
while (std::getline(fs, line))
{
std::stringstream ss(line);
if (line.size() == (size_t)(0))
{
}
else if (line.substr(0, 6) == "POINTS")
{
reading_points = true;
reading_tets = false;
ss.ignore(128, ' '); // ignore "POINTS"
ss >> n_points;
X.resize(n_points);
}
else if (line.substr(0, 5) == "CELLS")
{
reading_points = false;
reading_tets = true;
ss.ignore(128, ' '); // ignore "CELLS"
ss >> n_tets;
indices.resize(n_tets);
}
else if (line.substr(0, 10) == "CELL_TYPES")
{
reading_points = false;
reading_tets = false;
}
else if (reading_points)
{
btScalar p;
ss >> p;
position.setX(p);
ss >> p;
position.setY(p);
ss >> p;
position.setZ(p);
//printf("v %f %f %f\n", position.getX(), position.getY(), position.getZ());
X[x_count++] = position;
}
else if (reading_tets)
{
int d;
ss >> d;
if (d != 4)
{
printf("Load deformable failed: Only Tetrahedra are supported in VTK file.\n");
fs.close();
return 0;
}
ss.ignore(128, ' '); // ignore "4"
Index tet;
tet.resize(4);
for (size_t i = 0; i < 4; i++)
{
ss >> tet[i];
//printf("%d ", tet[i]);
}
//printf("\n");
indices[indices_count++] = tet;
}
}
btReducedDeformableBody* rsb = new btReducedDeformableBody(&worldInfo, n_points, &X[0], 0);
for (int i = 0; i < n_tets; ++i)
{
const Index& ni = indices[i];
rsb->appendTetra(ni[0], ni[1], ni[2], ni[3]);
{
rsb->appendLink(ni[0], ni[1], 0, true);
rsb->appendLink(ni[1], ni[2], 0, true);
rsb->appendLink(ni[2], ni[0], 0, true);
rsb->appendLink(ni[0], ni[3], 0, true);
rsb->appendLink(ni[1], ni[3], 0, true);
rsb->appendLink(ni[2], ni[3], 0, true);
}
}
btSoftBodyHelpers::generateBoundaryFaces(rsb);
rsb->initializeDmInverse();
rsb->m_tetraScratches.resize(rsb->m_tetras.size());
rsb->m_tetraScratchesTn.resize(rsb->m_tetras.size());
printf("Nodes: %u\r\n", rsb->m_nodes.size());
printf("Links: %u\r\n", rsb->m_links.size());
printf("Faces: %u\r\n", rsb->m_faces.size());
printf("Tetras: %u\r\n", rsb->m_tetras.size());
fs.close();
return rsb;
}
void btReducedDeformableBodyHelpers::readReducedDeformableInfoFromFiles(btReducedDeformableBody* rsb, const char* file_path)
{
// read in eigenmodes, stiffness and mass matrices
std::string eigenvalues_file = std::string(file_path) + "eigenvalues.bin";
btReducedDeformableBodyHelpers::readBinaryVec(rsb->m_eigenvalues, rsb->m_nReduced, eigenvalues_file.c_str());
std::string Kr_file = std::string(file_path) + "K_r_diag_mat.bin";
btReducedDeformableBodyHelpers::readBinaryVec(rsb->m_Kr, rsb->m_nReduced, Kr_file.c_str());
// std::string Mr_file = std::string(file_path) + "M_r_diag_mat.bin";
// btReducedDeformableBodyHelpers::readBinaryVec(rsb->m_Mr, rsb->m_nReduced, Mr_file.c_str());
std::string modes_file = std::string(file_path) + "modes.bin";
btReducedDeformableBodyHelpers::readBinaryMat(rsb->m_modes, rsb->m_nReduced, 3 * rsb->m_nFull, modes_file.c_str());
// read in full nodal mass
std::string M_file = std::string(file_path) + "M_diag_mat.bin";
btAlignedObjectArray<btScalar> mass_array;
btReducedDeformableBodyHelpers::readBinaryVec(mass_array, rsb->m_nFull, M_file.c_str());
rsb->setMassProps(mass_array);
// calculate the inertia tensor in the local frame
rsb->setInertiaProps();
// other internal initialization
rsb->internalInitialization();
}
// read in a vector from the binary file
void btReducedDeformableBodyHelpers::readBinaryVec(btReducedDeformableBody::tDenseArray& vec,
const unsigned int n_size, // #entries read
const char* file)
{
std::ifstream f_in(file, std::ios::in | std::ios::binary);
// first get size
unsigned int size;
f_in.read((char*)&size, sizeof(uint32_t));
btAssert(size >= n_size); // make sure the #requested mode is smaller than the #available modes
// read data
vec.resize(n_size);
double temp;
for (unsigned int i = 0; i < n_size; ++i)
{
f_in.read((char*)&temp, sizeof(double));
vec[i] = btScalar(temp);
}
f_in.close();
}
// read in a matrix from the binary file
void btReducedDeformableBodyHelpers::readBinaryMat(btReducedDeformableBody::tDenseMatrix& mat,
const unsigned int n_modes, // #modes, outer array size
const unsigned int n_full, // inner array size
const char* file)
{
std::ifstream f_in(file, std::ios::in | std::ios::binary);
// first get size
unsigned int v_size;
f_in.read((char*)&v_size, sizeof(uint32_t));
btAssert(v_size >= n_modes * n_full); // make sure the #requested mode is smaller than the #available modes
// read data
mat.resize(n_modes);
for (int i = 0; i < n_modes; ++i)
{
for (int j = 0; j < n_full; ++j)
{
double temp;
f_in.read((char*)&temp, sizeof(double));
if (mat[i].size() != n_modes)
mat[i].resize(n_full);
mat[i][j] = btScalar(temp);
}
}
f_in.close();
}
void btReducedDeformableBodyHelpers::calculateLocalInertia(btVector3& inertia, const btScalar mass, const btVector3& half_extents, const btVector3& margin)
{
btScalar lx = btScalar(2.) * (half_extents[0] + margin[0]);
btScalar ly = btScalar(2.) * (half_extents[1] + margin[1]);
btScalar lz = btScalar(2.) * (half_extents[2] + margin[2]);
inertia.setValue(mass / (btScalar(12.0)) * (ly * ly + lz * lz),
mass / (btScalar(12.0)) * (lx * lx + lz * lz),
mass / (btScalar(12.0)) * (lx * lx + ly * ly));
}
|
