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Diffstat (limited to 'thirdparty/bullet/LinearMath/btPolarDecomposition.h')
-rw-r--r-- | thirdparty/bullet/LinearMath/btPolarDecomposition.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/thirdparty/bullet/LinearMath/btPolarDecomposition.h b/thirdparty/bullet/LinearMath/btPolarDecomposition.h new file mode 100644 index 0000000000..1feea0f78e --- /dev/null +++ b/thirdparty/bullet/LinearMath/btPolarDecomposition.h @@ -0,0 +1,72 @@ +#ifndef POLARDECOMPOSITION_H +#define POLARDECOMPOSITION_H + +#include "btMatrix3x3.h" + +/** + * This class is used to compute the polar decomposition of a matrix. In + * general, the polar decomposition factorizes a matrix, A, into two parts: a + * unitary matrix (U) and a positive, semi-definite Hermitian matrix (H). + * However, in this particular implementation the original matrix, A, is + * required to be a square 3x3 matrix with real elements. This means that U will + * be an orthogonal matrix and H with be a positive-definite, symmetric matrix. + */ +class btPolarDecomposition +{ + public: + + + /** + * Creates an instance with optional parameters. + * + * @param tolerance - the tolerance used to determine convergence of the + * algorithm + * @param maxIterations - the maximum number of iterations used to achieve + * convergence + */ + btPolarDecomposition(btScalar tolerance = btScalar(0.0001), + unsigned int maxIterations = 16); + + /** + * Decomposes a matrix into orthogonal and symmetric, positive-definite + * parts. If the number of iterations returned by this function is equal to + * the maximum number of iterations, the algorithm has failed to converge. + * + * @param a - the original matrix + * @param u - the resulting orthogonal matrix + * @param h - the resulting symmetric matrix + * + * @return the number of iterations performed by the algorithm. + */ + unsigned int decompose(const btMatrix3x3& a, btMatrix3x3& u, btMatrix3x3& h) const; + + /** + * Returns the maximum number of iterations that this algorithm will perform + * to achieve convergence. + * + * @return maximum number of iterations + */ + unsigned int maxIterations() const; + + private: + btScalar m_tolerance; + unsigned int m_maxIterations; +}; + +/** + * This functions decomposes the matrix 'a' into two parts: an orthogonal matrix + * 'u' and a symmetric, positive-definite matrix 'h'. If the number of + * iterations returned by this function is equal to + * btPolarDecomposition::DEFAULT_MAX_ITERATIONS, the algorithm has failed to + * converge. + * + * @param a - the original matrix + * @param u - the resulting orthogonal matrix + * @param h - the resulting symmetric matrix + * + * @return the number of iterations performed by the algorithm. + */ +unsigned int polarDecompose(const btMatrix3x3& a, btMatrix3x3& u, btMatrix3x3& h); + +#endif // POLARDECOMPOSITION_H + |