From e8cb10de72698e6ac66d0ca3350a187da419eca4 Mon Sep 17 00:00:00 2001 From: Recep Aslantas Date: Mon, 24 Oct 2016 21:42:40 +0300 Subject: [PATCH] improve extracting euler angles --- include/cglm-euler.h | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/include/cglm-euler.h b/include/cglm-euler.h index 00dfb38..639c146 100644 --- a/include/cglm-euler.h +++ b/include/cglm-euler.h @@ -11,7 +11,7 @@ #include "cglm-common.h" /*! - * @brief euler angles (in radian) for xyz sequence + * @brief euler angles (in radian) using xyz sequence * * @param[in] m affine transform * @param[out] pitch x @@ -26,9 +26,24 @@ glm_euler_angles(mat4 m, float * __restrict roll) { if (m[2][0] < 1.0f) { if (m[2][0] > -1.0f) { - *yaw = asinf(m[2][0]); - *pitch = atan2f(-m[2][1], m[2][2]); - *roll = atan2f(-m[1][0], m[0][0]); + float a[2][3]; + int path; + + a[0][0] = asinf(m[2][0]); + a[1][0] = M_PI - a[0][0]; + + a[0][1] = atan2f(-m[2][1] / cosf(a[0][0]), m[2][2] / cosf(a[0][0])); + a[1][1] = atan2f(-m[2][1] / cosf(a[1][0]), m[2][2] / cosf(a[1][0])); + + a[0][2] = atan2f(-m[1][0] / cosf(a[0][0]), m[0][0] / cosf(a[0][0])); + a[1][2] = atan2f(-m[1][0] / cosf(a[1][0]), m[0][0] / cosf(a[1][0])); + + path = (fabsf(a[0][0]) + fabsf(a[0][1]) + fabsf(a[0][2])) > + (fabsf(a[1][0]) + fabsf(a[1][1]) + fabsf(a[1][2])); + + *yaw = a[path][0]; + *pitch = a[path][1]; + *roll = a[path][2]; } else { *yaw = -M_PI_2; *pitch = -atan2(m[0][1], m[2][1]);