diff options
| author | Inho Lee <inho.lee@qt.io> | 2022-04-19 11:30:19 +0200 |
|---|---|---|
| committer | Inho Lee <inho.lee@qt.io> | 2023-02-03 15:05:28 +0100 |
| commit | 1e5ae32c5596d598f7e6305613e12c044ea925a8 (patch) | |
| tree | b65925ead99f3192c1f50d64c94759314abad813 | |
| parent | e2bc6e02755845f8cd754e01d15df1f7e6d17e3a (diff) | |
Update comments in QQuaternion::getEulerAngles
A comment from the patch 6ffc8d8eb6c44fbd51e37770e7013c4610ead96d
is a little ambiguous. This patch is just to give information
about the modification.
Task-number: QTBUG-72103
Change-Id: I6bfc3ae926c118de0d969a4b44f438c24f8d4f72
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
(cherry picked from commit 8f9049ddbcedbc1f623acb7bfcd2b31c286f4583)
| -rw-r--r-- | src/gui/math3d/qquaternion.cpp | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/src/gui/math3d/qquaternion.cpp b/src/gui/math3d/qquaternion.cpp index 7145330cfd..c389b246d9 100644 --- a/src/gui/math3d/qquaternion.cpp +++ b/src/gui/math3d/qquaternion.cpp @@ -512,8 +512,9 @@ void QQuaternion::getEulerAngles(float *pitch, float *yaw, float *roll) const // https://ingmec.ual.es/~jlblanco/papers/jlblanco2010geometry3D_techrep.pdf // "A tutorial on SE(3) transformation parameterizations and on-manifold optimization". - // Normalize values even if the length is below the margin. Otherwise we might fail - // to detect Gimbal lock due to cumulative errors. + // We can only detect Gimbal lock when we normalize, which we can't do when + // length is nearly zero. Do so before multiplying co-ordinates, to avoid + // underflow. const float len = length(); const bool rescale = !qFuzzyIsNull(len); const float xps = rescale ? xp / len : xp; |