PK_VECTOR_transform_direction

PK_ERROR_code_t     PK_VECTOR_transform_direction
(
--- received arguments ---
PK_VECTOR1_t        direction,        --- direction
PK_TRANSF_t         transf,           --- transformation to apply

--- returned arguments ---
PK_VECTOR1_t *const direction_trans   --- new direction
)


This function applies the given transformation to the direction vector and
if necessary normalises the result.


Specific Errors:
    PK_ERROR_not_a_unit_vector    If 'direction' is not normalised (MILD)
    PK_ERROR_bad_component        'transf' contains a perspective component
                                  (MILD)