xref: /libCEED/examples/solids/qfunctions/common.h (revision 9ba83ac0e4b1fca39d6fa6737a318a9f0cbc172d)

// Copyright (c) 2017-2026, Lawrence Livermore National Security, LLC and other CEED contributors.
// All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
//
// SPDX-License-Identifier: BSD-2-Clause
//
// This file is part of CEED:  http://github.com/ceed

/// @file
/// Geometric factors for solid mechanics example using PETSc

#include <ceed/types.h>

// -----------------------------------------------------------------------------
// This QFunction sets up the geometric factors required for integration and coordinate transformations
//
// Reference (parent) coordinates: X
// Physical (current) coordinates: x
// Change of coordinate matrix: dxdX_{i,j} = x_{i,j} (indicial notation)
// Inverse of change of coordinate matrix: dXdx_{i,j} = (detJ^-1) * X_{i,j}
//
// All quadrature data is stored in 10 field vector of quadrature data.
//
// We require the transpose of the inverse of the Jacobian to properly compute integrals of the form: int( gradv u )
//
// Inverse of Jacobian:
//   dXdx_i,j = Aij / detJ
//
// Stored: Aij / detJ
//   in q_data[1:9] as
//              [A11 A12 A13]
//  (detJ^-1) * [A21 A22 A23]
//              [A31 A32 A33]
// -----------------------------------------------------------------------------
CEED_QFUNCTION(SetupGeo)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
  // Inputs
  const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0], (*w) = in[1];

  // Outputs
  CeedScalar(*q_data)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];

  CeedPragmaSIMD
      // Quadrature Point Loop
      for (CeedInt i = 0; i < Q; i++) {
    // Setup
    const CeedScalar J11  = J[0][0][i];
    const CeedScalar J21  = J[0][1][i];
    const CeedScalar J31  = J[0][2][i];
    const CeedScalar J12  = J[1][0][i];
    const CeedScalar J22  = J[1][1][i];
    const CeedScalar J32  = J[1][2][i];
    const CeedScalar J13  = J[2][0][i];
    const CeedScalar J23  = J[2][1][i];
    const CeedScalar J33  = J[2][2][i];
    const CeedScalar A11  = J22 * J33 - J23 * J32;
    const CeedScalar A12  = J13 * J32 - J12 * J33;
    const CeedScalar A13  = J12 * J23 - J13 * J22;
    const CeedScalar A21  = J23 * J31 - J21 * J33;
    const CeedScalar A22  = J11 * J33 - J13 * J31;
    const CeedScalar A23  = J13 * J21 - J11 * J23;
    const CeedScalar A31  = J21 * J32 - J22 * J31;
    const CeedScalar A32  = J12 * J31 - J11 * J32;
    const CeedScalar A33  = J11 * J22 - J12 * J21;
    const CeedScalar detJ = J11 * A11 + J21 * A12 + J31 * A13;

    // Qdata
    // -- Interp-to-Interp q_data
    q_data[0][i] = w[i] * detJ;

    // -- Interp-to-Grad q_data
    // Inverse of change of coordinate matrix: X_i,j
    q_data[1][i] = A11 / detJ;
    q_data[2][i] = A12 / detJ;
    q_data[3][i] = A13 / detJ;
    q_data[4][i] = A21 / detJ;
    q_data[5][i] = A22 / detJ;
    q_data[6][i] = A23 / detJ;
    q_data[7][i] = A31 / detJ;
    q_data[8][i] = A32 / detJ;
    q_data[9][i] = A33 / detJ;

  }  // End of Quadrature Point Loop

  return 0;
}
// -----------------------------------------------------------------------------