/** Create a particle model mesh */ void createMesh() { TriangleModel::ParticleMesh::UVs uvs; uvs.resize(nRows*nCols); const Real dy = width / (Real)(nCols - 1); const Real dx = height / (Real)(nRows - 1); Vector3r points[nRows*nCols]; for (int i = 0; i < nRows; i++) { for (int j = 0; j < nCols; j++) { const Real y = (Real)dy*j; const Real x = (Real)dx*i; points[i*nCols + j] = Vector3r(x, 1.0, y); uvs[i*nCols + j][0] = x/width; uvs[i*nCols + j][1] = y/height; } } const int nIndices = 6 * (nRows - 1)*(nCols - 1); TriangleModel::ParticleMesh::UVIndices uvIndices; uvIndices.resize(nIndices); unsigned int indices[nIndices]; int index = 0; for (int i = 0; i < nRows - 1; i++) { for (int j = 0; j < nCols - 1; j++) { int helper = 0; if (i % 2 == j % 2) helper = 1; indices[index] = i*nCols + j; indices[index + 1] = i*nCols + j + 1; indices[index + 2] = (i + 1)*nCols + j + helper; uvIndices[index] = i*nCols + j; uvIndices[index + 1] = i*nCols + j + 1; uvIndices[index + 2] = (i + 1)*nCols + j + helper; index += 3; indices[index] = (i + 1)*nCols + j + 1; indices[index + 1] = (i + 1)*nCols + j; indices[index + 2] = i*nCols + j + 1 - helper; uvIndices[index] = (i + 1)*nCols + j + 1; uvIndices[index + 1] = (i + 1)*nCols + j; uvIndices[index + 2] = i*nCols + j + 1 - helper; index += 3; } } model.addTriangleModel(nRows*nCols, nIndices / 3, &points[0], &indices[0], uvIndices, uvs); ParticleData &pd = model.getParticles(); for (unsigned int i = 0; i < pd.getNumberOfParticles(); i++) { pd.setMass(i, 1.0); } // Set mass of points to zero => make it static pd.setMass(0, 0.0); pd.setMass((nRows-1)*nCols, 0.0); // init constraints for (unsigned int cm = 0; cm < model.getTriangleModels().size(); cm++) { const unsigned int offset = model.getTriangleModels()[cm]->getIndexOffset(); IndexedFaceMesh &mesh = model.getTriangleModels()[cm]->getParticleMesh(); const unsigned int nEdges = mesh.numEdges(); const IndexedFaceMesh::Edge *edges = mesh.getEdges().data(); // distance constraints for (unsigned int i = 0; i < nEdges; i++) { const unsigned int v1 = edges[i].m_vert[0] + offset; const unsigned int v2 = edges[i].m_vert[1] + offset; model.addGenericDistanceConstraint(v1, v2); } // bending constraints const unsigned int *tris = mesh.getFaces().data(); for (unsigned int i = 0; i < nEdges; i++) { const int tri1 = edges[i].m_face[0]; const int tri2 = edges[i].m_face[1]; if ((tri1 != 0xffffffff) && (tri2 != 0xffffffff)) { // Find the triangle points which do not lie on the axis const int axisPoint1 = edges[i].m_vert[0]; const int axisPoint2 = edges[i].m_vert[1]; int point1 = -1; int point2 = -1; for (int j = 0; j < 3; j++) { if ((tris[3 * tri1 + j] != axisPoint1) && (tris[3 * tri1 + j] != axisPoint2)) { point1 = tris[3 * tri1 + j]; break; } } for (int j = 0; j < 3; j++) { if ((tris[3 * tri2 + j] != axisPoint1) && (tris[3 * tri2 + j] != axisPoint2)) { point2 = tris[3 * tri2 + j]; break; } } if ((point1 != -1) && (point2 != -1)) { const unsigned int vertex1 = point1 + offset; const unsigned int vertex2 = point2 + offset; const unsigned int vertex3 = edges[i].m_vert[0] + offset; const unsigned int vertex4 = edges[i].m_vert[1] + offset; model.addGenericIsometricBendingConstraint(vertex1, vertex2, vertex3, vertex4); } } } } std::cout << "Number of triangles: " << nIndices / 3 << "\n"; std::cout << "Number of vertices: " << nRows*nCols << "\n"; }
/** Create a particle model mesh */ void createClothMesh() { TriangleModel::ParticleMesh::UVs uvs; uvs.resize(nRows*nCols); const float dy = clothWidth / (float)(nCols - 1); const float dx = clothHeight / (float)(nRows - 1); Eigen::Vector3f points[nRows*nCols]; for (int i = 0; i < nRows; i++) { for (int j = 0; j < nCols; j++) { const float y = (float)dy*j; const float x = (float)dx*i; points[i*nCols + j] = Eigen::Vector3f(x - 5.0f, 4.0f, y - 5.0f); uvs[i*nCols + j][0] = x / clothWidth; uvs[i*nCols + j][1] = y / clothHeight; } } const int nIndices = 6 * (nRows - 1)*(nCols - 1); TriangleModel::ParticleMesh::UVIndices uvIndices; uvIndices.resize(nIndices); unsigned int indices[nIndices]; int index = 0; for (int i = 0; i < nRows - 1; i++) { for (int j = 0; j < nCols - 1; j++) { int helper = 0; if (i % 2 == j % 2) helper = 1; indices[index] = i*nCols + j; indices[index + 1] = i*nCols + j + 1; indices[index + 2] = (i + 1)*nCols + j + helper; uvIndices[index] = i*nCols + j; uvIndices[index + 1] = i*nCols + j + 1; uvIndices[index + 2] = (i + 1)*nCols + j + helper; index += 3; indices[index] = (i + 1)*nCols + j + 1; indices[index + 1] = (i + 1)*nCols + j; indices[index + 2] = i*nCols + j + 1 - helper; uvIndices[index] = (i + 1)*nCols + j + 1; uvIndices[index + 1] = (i + 1)*nCols + j; uvIndices[index + 2] = i*nCols + j + 1 - helper; index += 3; } } model.addTriangleModel(nRows*nCols, nIndices / 3, &points[0], &indices[0], uvIndices, uvs); ParticleData &pd = model.getParticles(); for (unsigned int i = 0; i < pd.getNumberOfParticles(); i++) { pd.setMass(i, 1.0); } // init constraints for (unsigned int cm = 0; cm < model.getTriangleModels().size(); cm++) { if (sim.getSimulationMethod() == 1) { const unsigned int offset = model.getTriangleModels()[cm]->getIndexOffset(); const unsigned int nEdges = model.getTriangleModels()[cm]->getParticleMesh().numEdges(); const IndexedFaceMesh::Edge *edges = model.getTriangleModels()[cm]->getParticleMesh().getEdges().data(); for (unsigned int i = 0; i < nEdges; i++) { const unsigned int v1 = edges[i].m_vert[0] + offset; const unsigned int v2 = edges[i].m_vert[1] + offset; model.addDistanceConstraint(v1, v2); } } else if (sim.getSimulationMethod() == 2) { const unsigned int offset = model.getTriangleModels()[cm]->getIndexOffset(); TriangleModel::ParticleMesh &mesh = model.getTriangleModels()[cm]->getParticleMesh(); const unsigned int *tris = mesh.getFaces().data(); const unsigned int nFaces = mesh.numFaces(); for (unsigned int i = 0; i < nFaces; i++) { const unsigned int v1 = tris[3 * i] + offset; const unsigned int v2 = tris[3 * i + 1] + offset; const unsigned int v3 = tris[3 * i + 2] + offset; model.addFEMTriangleConstraint(v1, v2, v3); } } else if (sim.getSimulationMethod() == 3) { const unsigned int offset = model.getTriangleModels()[cm]->getIndexOffset(); TriangleModel::ParticleMesh &mesh = model.getTriangleModels()[cm]->getParticleMesh(); const unsigned int *tris = mesh.getFaces().data(); const unsigned int nFaces = mesh.numFaces(); for (unsigned int i = 0; i < nFaces; i++) { const unsigned int v1 = tris[3 * i] + offset; const unsigned int v2 = tris[3 * i + 1] + offset; const unsigned int v3 = tris[3 * i + 2] + offset; model.addStrainTriangleConstraint(v1, v2, v3); } } if (sim.getBendingMethod() != 0) { const unsigned int offset = model.getTriangleModels()[cm]->getIndexOffset(); TriangleModel::ParticleMesh &mesh = model.getTriangleModels()[cm]->getParticleMesh(); unsigned int nEdges = mesh.numEdges(); const TriangleModel::ParticleMesh::Edge *edges = mesh.getEdges().data(); const unsigned int *tris = mesh.getFaces().data(); for (unsigned int i = 0; i < nEdges; i++) { const int tri1 = edges[i].m_face[0]; const int tri2 = edges[i].m_face[1]; if ((tri1 != 0xffffffff) && (tri2 != 0xffffffff)) { // Find the triangle points which do not lie on the axis const int axisPoint1 = edges[i].m_vert[0]; const int axisPoint2 = edges[i].m_vert[1]; int point1 = -1; int point2 = -1; for (int j = 0; j < 3; j++) { if ((tris[3 * tri1 + j] != axisPoint1) && (tris[3 * tri1 + j] != axisPoint2)) { point1 = tris[3 * tri1 + j]; break; } } for (int j = 0; j < 3; j++) { if ((tris[3 * tri2 + j] != axisPoint1) && (tris[3 * tri2 + j] != axisPoint2)) { point2 = tris[3 * tri2 + j]; break; } } if ((point1 != -1) && (point2 != -1)) { const unsigned int vertex1 = point1 + offset; const unsigned int vertex2 = point2 + offset; const unsigned int vertex3 = edges[i].m_vert[0] + offset; const unsigned int vertex4 = edges[i].m_vert[1] + offset; if (sim.getBendingMethod() == 1) model.addDihedralConstraint(vertex1, vertex2, vertex3, vertex4); else if (sim.getBendingMethod() == 2) model.addIsometricBendingConstraint(vertex1, vertex2, vertex3, vertex4); } } } } } std::cout << "Number of triangles: " << nIndices / 3 << "\n"; std::cout << "Number of vertices: " << nRows*nCols << "\n"; }