From d5cd7d31c92593c593c8c809588284d61316c2ec Mon Sep 17 00:00:00 2001 From: Stanislaw Halik Date: Sat, 3 Mar 2018 12:59:38 +0100 Subject: compat/euler: move gimbal lock from yaw to roll Tested-by: Yuri Vostrenkov --- compat/euler.cpp | 59 +++++++++++++++++++++----------------------------------- 1 file changed, 22 insertions(+), 37 deletions(-) diff --git a/compat/euler.cpp b/compat/euler.cpp index 44b34f90..e9789bee 100644 --- a/compat/euler.cpp +++ b/compat/euler.cpp @@ -2,53 +2,38 @@ #include "math-imports.hpp" #include +// rotation order is XYZ + namespace euler { euler_t OTR_COMPAT_EXPORT rmat_to_euler(const rmat& R) { - const double cy = sqrt(R(2,2)*R(2, 2) + R(2, 1)*R(2, 1)); - const bool large_enough = cy > 1e-10; - if (large_enough) - return { - atan2(-R(1, 0), R(0, 0)), - atan2(R(2, 0), cy), - atan2(-R(2, 1), R(2, 2)) - }; - else - return { - atan2(R(0, 1), R(1, 1)), - atan2(R(2, 0), cy), - 0 - }; + double alpha, beta, gamma; + + beta = atan2( -R(2,0), sqrt(R(2,1)*R(2,1) + R(2,2)*R(2,2)) ); + alpha = atan2( R(1,0), R(0,0)); + gamma = atan2( R(2,1), R(2,2)); + + return { alpha, beta, gamma }; } -// tait-bryan angles, not euler -rmat OTR_COMPAT_EXPORT euler_to_rmat(const euler_t& input) +rmat OTR_COMPAT_EXPORT euler_to_rmat(const euler_t& e) { - const double H = -input(0); - const double P = -input(1); - const double B = -input(2); + const double X = -e(2); + const double Y = -e(1); + const double Z = -e(0); - const auto c1 = cos(H); - const auto s1 = sin(H); - const auto c2 = cos(P); - const auto s2 = sin(P); - const auto c3 = cos(B); - const auto s3 = sin(B); + const double cx = cos(X); + const double sx = sin(X); + const double cy = cos(Y); + const double sy = sin(Y); + const double cz = cos(Z); + const double sz = sin(Z); return { - // z - c1*c2, - c1*s2*s3 - c3*s1, - s1*s3 + c1*c3*s2, - // y - c2*s1, - c1*c3 + s1*s2*s3, - c3*s1*s2 - c1*s3, - // x - -s2, - c2*s3, - c2*c3 + cy*cz, -cy*sz, sy, + cz*sx*sy + cx*sz, cx*cz - sx*sy*sz, -cy*sx, + -cx*cz*sy + sx*sz, cz*sx + cx*sy*sz, cx*cy, }; } -- cgit v1.2.3