xref: /libCEED/examples/fluids/qfunctions/setupgeo.h (revision 1ea55a34129e65adf46cc9aad604e9be02563d89)
1 // Copyright (c) 2017-2023, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
3 //
4 // SPDX-License-Identifier: BSD-2-Clause
5 //
6 // This file is part of CEED:  http://github.com/ceed
7 
8 /// @file
9 /// Geometric factors (3D) for Navier-Stokes example using PETSc
10 
11 #ifndef setup_geo_h
12 #define setup_geo_h
13 
14 #include <ceed.h>
15 #include <math.h>
16 
17 #include "setupgeo_helpers.h"
18 #include "utils.h"
19 
20 // *****************************************************************************
21 // This QFunction sets up the geometric factors required for integration and coordinate transformations
22 //
23 // Reference (parent) coordinates: X
24 // Physical (current) coordinates: x
25 // Change of coordinate matrix: dxdX_{i,j} = x_{i,j} (indicial notation)
26 // Inverse of change of coordinate matrix: dXdx_{i,j} = (detJ^-1) * X_{i,j}
27 //
28 // All quadrature data is stored in 10 field vector of quadrature data.
29 //
30 // We require the determinant of the Jacobian to properly compute integrals of the form: int( v u )
31 //
32 // Determinant of Jacobian:
33 //   detJ = J11*A11 + J21*A12 + J31*A13
34 //     Jij = Jacobian entry ij
35 //     Aij = Adjugate ij
36 //
37 // Stored: w detJ
38 //   in q_data[0]
39 //
40 // We require the transpose of the inverse of the Jacobian to properly compute integrals of the form: int( gradv u )
41 //
42 // Inverse of Jacobian:
43 //   dXdx_i,j = Aij / detJ
44 //
45 // Stored: Aij / detJ
46 //   in q_data[1:9] as
47 //   (detJ^-1) * [A11 A12 A13]
48 //               [A21 A22 A23]
49 //               [A31 A32 A33]
50 // *****************************************************************************
51 CEED_QFUNCTION(Setup)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
52   const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0];
53   const CeedScalar(*w)                = in[1];
54   CeedScalar(*q_data)                 = out[0];
55 
56   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
57     CeedScalar detJ, dXdx[3][3];
58     InvertMappingJacobian_3D(Q, i, J, dXdx, &detJ);
59     const CeedScalar wdetJ = w[i] * detJ;
60 
61     StoredValuesPack(Q, i, 0, 1, &wdetJ, q_data);
62     StoredValuesPack(Q, i, 1, 9, (const CeedScalar *)dXdx, q_data);
63   }
64   return 0;
65 }
66 
67 // *****************************************************************************
68 // This QFunction sets up the geometric factor required for integration when reference coordinates are in 2D and the physical coordinates are in 3D
69 //
70 // Reference (parent) 2D coordinates: X
71 // Physical (current) 3D coordinates: x
72 // Change of coordinate matrix:
73 //   dxdX_{i,j} = dx_i/dX_j (indicial notation) [3 * 2]
74 // Inverse change of coordinate matrix:
75 //   dXdx_{i,j} = dX_i/dx_j (indicial notation) [2 * 3]
76 //
77 // (J1,J2,J3) is given by the cross product of the columns of dxdX_{i,j}
78 //
79 // detJb is the magnitude of (J1,J2,J3)
80 //
81 // dXdx is calculated via Moore–Penrose inverse:
82 //
83 //   dX_i/dx_j = (dxdX^T dxdX)^(-1) dxdX
84 //             = (dx_l/dX_i * dx_l/dX_k)^(-1) dx_j/dX_k
85 //
86 // All quadrature data is stored in 10 field vector of quadrature data.
87 //
88 // We require the determinant of the Jacobian to properly compute integrals of
89 //   the form: int( u v )
90 //
91 // Stored: w detJb
92 //   in q_data_sur[0]
93 //
94 // Normal vector = (J1,J2,J3) / detJb
95 //
96 //   - TODO Could possibly remove normal vector, as it could be calculated in the Qfunction from dXdx
97 //    See https://github.com/CEED/libCEED/pull/868#discussion_r871979484
98 // Stored: (J1,J2,J3) / detJb
99 //   in q_data_sur[1:3] as
100 //   (detJb^-1) * [ J1 ]
101 //                [ J2 ]
102 //                [ J3 ]
103 //
104 // Stored: dXdx_{i,j}
105 //   in q_data_sur[4:9] as
106 //    [dXdx_11 dXdx_12 dXdx_13]
107 //    [dXdx_21 dXdx_22 dXdx_23]
108 // *****************************************************************************
109 CEED_QFUNCTION(SetupBoundary)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
110   const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0];
111   const CeedScalar(*w)                = in[1];
112   CeedScalar(*q_data_sur)             = out[0];
113 
114   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
115     CeedScalar detJb, normal[3], dXdx[2][3];
116 
117     NormalVectorFromdxdX_3D(Q, i, J, normal, &detJb);
118     InvertBoundaryMappingJacobian_3D(Q, i, J, dXdx);
119     const CeedScalar wdetJ = w[i] * detJb;
120 
121     StoredValuesPack(Q, i, 0, 1, &wdetJ, q_data_sur);
122     StoredValuesPack(Q, i, 1, 3, normal, q_data_sur);
123     StoredValuesPack(Q, i, 4, 6, (const CeedScalar *)dXdx, q_data_sur);
124   }
125   return 0;
126 }
127 
128 // *****************************************************************************
129 
130 #endif  // setup_geo_h
131