* Extract the rotation component of the transformation matrix.
*
* @param matrix the transformation matrix
- * @return the angle (in degrees) by which the transformation rotates the frame.
- * The angle will be in range [-180.0, 180.0], or NaN if the matrix is
- * singular.
+ * @return the angle (in degrees) by which the transformation rotates the frame
+ * counterclockwise. The angle will be in range [-180.0, 180.0],
+ * or NaN if the matrix is singular.
*
* @note floating point numbers are inherently inexact, so callers are
* recommended to round the return value to nearest integer before use.
double av_display_rotation_get(const int32_t matrix[9]);
/**
- * Initialize a transformation matrix describing a pure rotation by the
- * specified angle (in degrees).
+ * Initialize a transformation matrix describing a pure counterclockwise
+ * rotation by the specified angle (in degrees).
*
* @param matrix an allocated transformation matrix (will be fully overwritten
* by this function)