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Diffstat (limited to 'src/gui/math3d/qquaternion.cpp')
| -rw-r--r-- | src/gui/math3d/qquaternion.cpp | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/src/gui/math3d/qquaternion.cpp b/src/gui/math3d/qquaternion.cpp index 6914a0b45e..4b35ee4e79 100644 --- a/src/gui/math3d/qquaternion.cpp +++ b/src/gui/math3d/qquaternion.cpp @@ -720,8 +720,38 @@ QQuaternion QQuaternion::fromAxes(const QVector3D &xAxis, const QVector3D &yAxis /*! \since 5.5 + Constructs the quaternion using specified forward direction \a direction + and upward direction \a up. + If the upward direction was not specified or the forward and upward + vectors are collinear, a new orthonormal upward direction will be generated. + + \sa fromAxes(), rotationTo() +*/ +QQuaternion QQuaternion::fromDirection(const QVector3D &direction, const QVector3D &up) +{ + if (qFuzzyIsNull(direction.x()) && qFuzzyIsNull(direction.y()) && qFuzzyIsNull(direction.z())) + return QQuaternion(); + + const QVector3D zAxis(direction.normalized()); + QVector3D xAxis(QVector3D::crossProduct(up, zAxis)); + if (qFuzzyIsNull(xAxis.lengthSquared())) { + // collinear or invalid up vector; derive shortest arc to new direction + return QQuaternion::rotationTo(QVector3D(0.0f, 0.0f, 1.0f), zAxis); + } + + xAxis.normalize(); + const QVector3D yAxis(QVector3D::crossProduct(zAxis, xAxis)); + + return QQuaternion::fromAxes(xAxis, yAxis, zAxis); +} + +/*! + \since 5.5 + Returns the shortest arc quaternion to rotate from the direction described by the vector \a from to the direction described by the vector \a to. + + \sa fromDirection() */ QQuaternion QQuaternion::rotationTo(const QVector3D &from, const QVector3D &to) { |