gistfile1.txt

    /**
     * @name Initial orientation
     * @{
     * There fields describe additional rotations applied to the sphere after
     * the video frame is mapped onto it. The sphere is rotated around the
     * viewer, who remains stationary.
     *
     * A positive yaw moves the left half of the frame forward.
     * A positive pitch moves the bottom half of the frame upward.
     * A positive roll moves the left half of the frame downward.
     * These values are exported as 16.16 fixed point.
     *
     * See this equirectangular projection as example:
     *
     * @code{.unparsed}
     *                   Yaw
     *     -180           0           180
     *   90 +-------------+-------------+  180
     *      |             |             |                   z| => up
     * P    |             |             |                    |
     * i    |             ^             |                   0|____ => right
     * t  0 +-------------X-------------+    0 Roll         /     x
     * c    |             |             |                 y/
     * h    |             |             |                 => forward
     *      |             |             |
     *  -90 +-------------+-------------+ -180
     *
     * X - the default camera center
     * ^ - the default up vector
     * @endcode
     *
     * The order of transformation is always yaw, followed by pitch, and
     * finally by roll.
     */
    int32_t yaw;   ///< Rotation around the up vector [-180, 180].
    int32_t pitch; ///< Rotation around the right vector [-90, 90].
    int32_t roll;  ///< Rotation around the forward vector [-180, 180].
    /**
     * @}
     */