PK_FACE_find_extreme

PK_ERROR_code_t    PK_FACE_find_extreme
(
--- received arguments ---
PK_FACE_t          face,            --- face on which extreme sought
PK_VECTOR_t        direction_1,     --- first direction
PK_VECTOR_t        direction_2,     --- second direction
PK_VECTOR_t        direction_3,     --- third direction

--- returned arguments ---
PK_VECTOR_t *const extreme,         --- position of extreme point
PK_TOPOL_t  *const topol            --- topology on which extreme point lies
)


This function finds the extreme point on the given 'face' in 'direction_1'.
If this extreme is not a single point, the 'direction_2' and 'direction_3'
are used successively to reduce the number of extreme points to one.


Specific Errors:
    PK_ERROR_coplanar               directions are coplanar (MILD)
    PK_ERROR_missing_geom           insufficient geometry (MILD)
    PK_ERROR_cant_find_extreme      failed to find extreme point (MILD)


'topol' returns the topological entity of the lowest dimensionality on which
the extreme lies (in order of precedence: vertex, edge, face).

The face may not be rubber.
The three directions must not be coplanar.