diff options
Diffstat (limited to 'thirdparty/bullet/BulletSoftBody/btConjugateResidual.h')
-rw-r--r-- | thirdparty/bullet/BulletSoftBody/btConjugateResidual.h | 256 |
1 files changed, 90 insertions, 166 deletions
diff --git a/thirdparty/bullet/BulletSoftBody/btConjugateResidual.h b/thirdparty/bullet/BulletSoftBody/btConjugateResidual.h index 7b211c4172..6146120365 100644 --- a/thirdparty/bullet/BulletSoftBody/btConjugateResidual.h +++ b/thirdparty/bullet/BulletSoftBody/btConjugateResidual.h @@ -15,174 +15,98 @@ #ifndef BT_CONJUGATE_RESIDUAL_H #define BT_CONJUGATE_RESIDUAL_H -#include <iostream> -#include <cmath> -#include <limits> -#include <LinearMath/btAlignedObjectArray.h> -#include <LinearMath/btVector3.h> -#include <LinearMath/btScalar.h> -#include "LinearMath/btQuickprof.h" +#include "btKrylovSolver.h" + template <class MatrixX> -class btConjugateResidual +class btConjugateResidual : public btKrylovSolver<MatrixX> { - typedef btAlignedObjectArray<btVector3> TVStack; - TVStack r,p,z,temp_p, temp_r, best_x; - // temp_r = A*r - // temp_p = A*p - // z = M^(-1) * temp_p = M^(-1) * A * p - int max_iterations; - btScalar tolerance_squared, best_r; + typedef btAlignedObjectArray<btVector3> TVStack; + typedef btKrylovSolver<MatrixX> Base; + TVStack r, p, z, temp_p, temp_r, best_x; + // temp_r = A*r + // temp_p = A*p + // z = M^(-1) * temp_p = M^(-1) * A * p + btScalar best_r; + public: - btConjugateResidual(const int max_it_in) - : max_iterations(max_it_in) - { - tolerance_squared = 1e-2; - } - - virtual ~btConjugateResidual(){} - - // return the number of iterations taken - int solve(MatrixX& A, TVStack& x, const TVStack& b, bool verbose = false) - { - BT_PROFILE("CRSolve"); - btAssert(x.size() == b.size()); - reinitialize(b); - // r = b - A * x --with assigned dof zeroed out - A.multiply(x, temp_r); // borrow temp_r here to store A*x - r = sub(b, temp_r); - // z = M^(-1) * r - A.precondition(r, z); // borrow z to store preconditioned r - r = z; - btScalar residual_norm = norm(r); - if (residual_norm <= tolerance_squared) { - if (verbose) - { - std::cout << "Iteration = 0" << std::endl; - std::cout << "Two norm of the residual = " << residual_norm << std::endl; - } - return 0; - } - p = r; - btScalar r_dot_Ar, r_dot_Ar_new; - // temp_p = A*p - A.multiply(p, temp_p); - // temp_r = A*r - temp_r = temp_p; - r_dot_Ar = dot(r, temp_r); - for (int k = 1; k <= max_iterations; k++) { - // z = M^(-1) * Ap - A.precondition(temp_p, z); - // alpha = r^T * A * r / (Ap)^T * M^-1 * Ap) - btScalar alpha = r_dot_Ar / dot(temp_p, z); - // x += alpha * p; - multAndAddTo(alpha, p, x); - // r -= alpha * z; - multAndAddTo(-alpha, z, r); - btScalar norm_r = norm(r); - if (norm_r < best_r) - { - best_x = x; - best_r = norm_r; - if (norm_r < tolerance_squared) { - if (verbose) - { - std::cout << "ConjugateResidual iterations " << k << std::endl; - } - return k; - } - else - { - if (verbose) - { - std::cout << "ConjugateResidual iterations " << k << " has residual "<< norm_r << std::endl; - } - } - } - // temp_r = A * r; - A.multiply(r, temp_r); - r_dot_Ar_new = dot(r, temp_r); - btScalar beta = r_dot_Ar_new/r_dot_Ar; - r_dot_Ar = r_dot_Ar_new; - // p = beta*p + r; - p = multAndAdd(beta, p, r); - // temp_p = beta*temp_p + temp_r; - temp_p = multAndAdd(beta, temp_p, temp_r); - } - if (verbose) - { - std::cout << "ConjugateResidual max iterations reached " << max_iterations << std::endl; - } - x = best_x; - return max_iterations; - } - - void reinitialize(const TVStack& b) - { - r.resize(b.size()); - p.resize(b.size()); - z.resize(b.size()); - temp_p.resize(b.size()); - temp_r.resize(b.size()); - best_x.resize(b.size()); - best_r = SIMD_INFINITY; - } - - TVStack sub(const TVStack& a, const TVStack& b) - { - // c = a-b - btAssert(a.size() == b.size()); - TVStack c; - c.resize(a.size()); - for (int i = 0; i < a.size(); ++i) - { - c[i] = a[i] - b[i]; - } - return c; - } - - btScalar squaredNorm(const TVStack& a) - { - return dot(a,a); - } - - btScalar norm(const TVStack& a) - { - btScalar ret = 0; - for (int i = 0; i < a.size(); ++i) - { - for (int d = 0; d < 3; ++d) - { - ret = btMax(ret, btFabs(a[i][d])); - } - } - return ret; - } - - btScalar dot(const TVStack& a, const TVStack& b) - { - btScalar ans(0); - for (int i = 0; i < a.size(); ++i) - ans += a[i].dot(b[i]); - return ans; - } - - void multAndAddTo(btScalar s, const TVStack& a, TVStack& result) - { - // result += s*a - btAssert(a.size() == result.size()); - for (int i = 0; i < a.size(); ++i) - result[i] += s * a[i]; - } - - TVStack multAndAdd(btScalar s, const TVStack& a, const TVStack& b) - { - // result = a*s + b - TVStack result; - result.resize(a.size()); - for (int i = 0; i < a.size(); ++i) - result[i] = s * a[i] + b[i]; - return result; - } + btConjugateResidual(const int max_it_in) + : Base(max_it_in, 1e-8) + { + } + + virtual ~btConjugateResidual() {} + + // return the number of iterations taken + int solve(MatrixX& A, TVStack& x, const TVStack& b, bool verbose = false) + { + BT_PROFILE("CRSolve"); + btAssert(x.size() == b.size()); + reinitialize(b); + // r = b - A * x --with assigned dof zeroed out + A.multiply(x, temp_r); // borrow temp_r here to store A*x + r = this->sub(b, temp_r); + // z = M^(-1) * r + A.precondition(r, z); // borrow z to store preconditioned r + r = z; + btScalar residual_norm = this->norm(r); + if (residual_norm <= Base::m_tolerance) + { + return 0; + } + p = r; + btScalar r_dot_Ar, r_dot_Ar_new; + // temp_p = A*p + A.multiply(p, temp_p); + // temp_r = A*r + temp_r = temp_p; + r_dot_Ar = this->dot(r, temp_r); + for (int k = 1; k <= Base::m_maxIterations; k++) + { + // z = M^(-1) * Ap + A.precondition(temp_p, z); + // alpha = r^T * A * r / (Ap)^T * M^-1 * Ap) + btScalar alpha = r_dot_Ar / this->dot(temp_p, z); + // x += alpha * p; + this->multAndAddTo(alpha, p, x); + // r -= alpha * z; + this->multAndAddTo(-alpha, z, r); + btScalar norm_r = this->norm(r); + if (norm_r < best_r) + { + best_x = x; + best_r = norm_r; + if (norm_r < Base::m_tolerance) + { + return k; + } + } + // temp_r = A * r; + A.multiply(r, temp_r); + r_dot_Ar_new = this->dot(r, temp_r); + btScalar beta = r_dot_Ar_new / r_dot_Ar; + r_dot_Ar = r_dot_Ar_new; + // p = beta*p + r; + p = this->multAndAdd(beta, p, r); + // temp_p = beta*temp_p + temp_r; + temp_p = this->multAndAdd(beta, temp_p, temp_r); + } + if (verbose) + { + std::cout << "ConjugateResidual max iterations reached, residual = " << best_r << std::endl; + } + x = best_x; + return Base::m_maxIterations; + } + + void reinitialize(const TVStack& b) + { + r.resize(b.size()); + p.resize(b.size()); + z.resize(b.size()); + temp_p.resize(b.size()); + temp_r.resize(b.size()); + best_x.resize(b.size()); + best_r = SIMD_INFINITY; + } }; #endif /* btConjugateResidual_h */ - |