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
#include "moab/LocalDiscretization/LinearHex.hpp"
#include "moab/Matrix3.hpp"
#include "moab/Forward.hpp"
#include <cmath>
#include <limits>

namespace moab
{

const double LinearHex::corner[8][3] = { { -1, -1, -1 }, { 1, -1, -1 }, { 1, 1, -1 }, { -1, 1, -1 },
                                         { -1, -1, 1 },  { 1, -1, 1 },  { 1, 1, 1 },  { -1, 1, 1 } };

/* For each point, its weight and location are stored as an array.
   Hence, the inner dimension is 2, the outer dimension is gauss_count.
   We use a one-point Gaussian quadrature, since it integrates linear functions exactly.
*/
const double LinearHex::gauss[1][2] = { { 2.0, 0.0 } };

ErrorCode LinearHex::jacobianFcn( const double* params,
                                  const double* verts,
                                  const int /*nverts*/,
                                  const int ndim,
                                  double*,
                                  double* result )
{
    assert( params && verts );
    Matrix3* J = reinterpret_cast< Matrix3* >( result );
    *J         = Matrix3( 0.0 );
    for( unsigned i = 0; i < 8; ++i )
    {
        const double params_p    = 1 + params[0] * corner[i][0];
        const double eta_p       = 1 + params[1] * corner[i][1];
        const double zeta_p      = 1 + params[2] * corner[i][2];
        const double dNi_dparams = corner[i][0] * eta_p * zeta_p;
        const double dNi_deta    = corner[i][1] * params_p * zeta_p;
        const double dNi_dzeta   = corner[i][2] * params_p * eta_p;
        ( *J )( 0, 0 ) += dNi_dparams * verts[i * ndim + 0];
        ( *J )( 1, 0 ) += dNi_dparams * verts[i * ndim + 1];
        ( *J )( 2, 0 ) += dNi_dparams * verts[i * ndim + 2];
        ( *J )( 0, 1 ) += dNi_deta * verts[i * ndim + 0];
        ( *J )( 1, 1 ) += dNi_deta * verts[i * ndim + 1];
        ( *J )( 2, 1 ) += dNi_deta * verts[i * ndim + 2];
        ( *J )( 0, 2 ) += dNi_dzeta * verts[i * ndim + 0];
        ( *J )( 1, 2 ) += dNi_dzeta * verts[i * ndim + 1];
        ( *J )( 2, 2 ) += dNi_dzeta * verts[i * ndim + 2];
    }
    ( *J ) *= 0.125;
    return MB_SUCCESS;
}  // LinearHex::jacobian()

ErrorCode LinearHex::evalFcn( const double* params,
                              const double* field,
                              const int /*ndim*/,
                              const int num_tuples,
                              double*,
                              double* result )
{
    assert( params && field && num_tuples != -1 );
    for( int i = 0; i < num_tuples; i++ )
        result[i] = 0.0;
    for( unsigned i = 0; i < 8; ++i )
    {
        const double N_i =
            ( 1 + params[0] * corner[i][0] ) * ( 1 + params[1] * corner[i][1] ) * ( 1 + params[2] * corner[i][2] );
        for( int j = 0; j < num_tuples; j++ )
            result[j] += N_i * field[i * num_tuples + j];
    }
    for( int i = 0; i < num_tuples; i++ )
        result[i] *= 0.125;

    return MB_SUCCESS;
}

ErrorCode LinearHex::integrateFcn( const double* field,
                                   const double* verts,
                                   const int nverts,
                                   const int ndim,
                                   const int num_tuples,
                                   double* work,
                                   double* result )
{
    assert( field && verts && num_tuples != -1 );
    double tmp_result[8];
    ErrorCode rval = MB_SUCCESS;<--- Variable 'rval' is assigned a value that is never used.
    for( int i = 0; i < num_tuples; i++ )
        result[i] = 0.0;
    CartVect x;
    Matrix3 J;
    for( unsigned int j1 = 0; j1 < LinearHex::gauss_count; ++j1 )
    {
        x[0]      = LinearHex::gauss[j1][1];
        double w1 = LinearHex::gauss[j1][0];
        for( unsigned int j2 = 0; j2 < LinearHex::gauss_count; ++j2 )
        {
            x[1]      = LinearHex::gauss[j2][1];
            double w2 = LinearHex::gauss[j2][0];
            for( unsigned int j3 = 0; j3 < LinearHex::gauss_count; ++j3 )
            {
                x[2]      = LinearHex::gauss[j3][1];
                double w3 = LinearHex::gauss[j3][0];
                rval      = evalFcn( x.array(), field, ndim, num_tuples, NULL, tmp_result );
                if( MB_SUCCESS != rval ) return rval;
                rval = jacobianFcn( x.array(), verts, nverts, ndim, work, J[0] );
                if( MB_SUCCESS != rval ) return rval;
                double tmp_det = w1 * w2 * w3 * J.determinant();
                for( int i = 0; i < num_tuples; i++ )
                    result[i] += tmp_result[i] * tmp_det;
            }
        }
    }

    return MB_SUCCESS;
}  // LinearHex::integrate_vector()

ErrorCode LinearHex::reverseEvalFcn( EvalFcn eval,
                                     JacobianFcn jacob,
                                     InsideFcn ins,
                                     const double* posn,
                                     const double* verts,
                                     const int nverts,
                                     const int ndim,
                                     const double iter_tol,
                                     const double inside_tol,
                                     double* work,
                                     double* params,
                                     int* is_inside )
{
    assert( posn && verts );
    return EvalSet::evaluate_reverse( eval, jacob, ins, posn, verts, nverts, ndim, iter_tol, inside_tol, work, params,
                                      is_inside );
}

int LinearHex::insideFcn( const double* params, const int ndim, const double tol )
{
    return EvalSet::inside_function( params, ndim, tol );
}

ErrorCode LinearHex::normalFcn( const int ientDim,
                                const int facet,
                                const int nverts,
                                const double* verts,
                                double normal[3] )
{
    // assert(facet < 6 && ientDim == 2 && nverts == 8);
    if( nverts != 8 ) MB_SET_ERR( MB_FAILURE, "Incorrect vertex count for passed hex :: expected value = 8 " );
    if( ientDim != 2 ) MB_SET_ERR( MB_FAILURE, "Requesting normal for unsupported dimension :: expected value = 2 " );
    if( facet > 6 || facet < 0 ) MB_SET_ERR( MB_FAILURE, "Incorrect local face id :: expected value = one of 0-5" );

    int id0 = CN::mConnectivityMap[MBHEX][ientDim - 1].conn[facet][0];
    int id1 = CN::mConnectivityMap[MBHEX][ientDim - 1].conn[facet][1];
    int id2 = CN::mConnectivityMap[MBHEX][ientDim - 1].conn[facet][3];

    double x0[3], x1[3];

    for( int i = 0; i < 3; i++ )
    {
        x0[i] = verts[3 * id1 + i] - verts[3 * id0 + i];
        x1[i] = verts[3 * id2 + i] - verts[3 * id0 + i];
    }

    double a   = x0[1] * x1[2] - x1[1] * x0[2];
    double b   = x1[0] * x0[2] - x0[0] * x1[2];
    double c   = x0[0] * x1[1] - x1[0] * x0[1];
    double nrm = sqrt( a * a + b * b + c * c );

    if( nrm > std::numeric_limits< double >::epsilon() )
    {
        normal[0] = a / nrm;
        normal[1] = b / nrm;
        normal[2] = c / nrm;
    }
    return MB_SUCCESS;
}

}  // namespace moab