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PK_GEOM_range_vector |
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PK_ERROR_code_t PK_GEOM_range_vector
(
--- received arguments ---
PK_GEOM_t geom, --- geometrical entity
PK_VECTOR_t vector, --- position vector
const PK_GEOM_range_vector_o_t *options, --- options structure [PF]
--- returned arguments ---
PK_range_result_t *const range_result, --- if range data returned
PK_range_1_r_t *const range --- range data
)
This function finds the global minimum separation between a geometrical
entity and a position.
This function offers partial support for facet geometry [PF]
Specific Errors:
PK_ERROR_bad_option_data bad option data given (MILD)
PK_ERROR_wrong_entity given entity is of the wrong type (MILD)
PK_ERROR_missing_geom given entity has missing geometry (MILD)
PK_ERROR_bad_parameter bad parameter given (MILD)
PK_ERROR_no_closest_approach failed to find closest approach (MILD)
PK_GEOM_range_vector will find the global closest approach between the
geometrical entity 'geom' and a position vector 'vector'.
The following geometry types are supported:
- surface, curve and point.
The function returns 'range_result' which can be one of three values:
PK_range_result_found_c the separation has been successfully found.
PK_range_result_lower_c minimum separation is less than the provided
lower bound.
PK_range_result_upper_c no separation is less than the provided
upper bound.
If 'range_result' is equal to PK_range_result_found_c, then a range data will
also be returned in 'range', this consists of a structure of type
PK_range_1_r_t, and contains a double 'distance', which is the
separation distance between the geometrical entity and the vector provided, and
a structure of type PK_range_end_t, which provides information on the
end of the line of separation on the entity as follows:
'entity' : the geometry supplied in 'geom'.
'sub_entity' : not applicable, PK_ENTITY_null will be returned.
'vector' : the end position on 'entity'.
'parameters' : an array of two parameters of the end position holding
curve or surface parameter(s). Which parameterisation is
used is dependent upon the geometry of the entity
returned.
If curve parameterisation is used the 2nd parameter should
be ignored.
The table below indicates which parameterisation
is used and when:
-------------------------------------------------------
| Entity | Identified | Geometry used for |
| | Sub-Entity | solution parameterisation |
|-----------|--------------|----------------------------|
| | | |
| point | none | none |
| curve | none | curve |
| surface | none | surface |
| | | |
-------------------------------------------------------
The curve and surface parameter values returned
will be the same as would be returned by the
parameterisation functions PK_CURVE_parameterise_vector
and PK_SURF_parameterise_vector.
'region' : a logical value - whether the solution is regional. If
PK_LOGICAL_true, the solution is a regional solution upon
the entity (ie. it is possible to move from solution point
pair without the distance changing )
The identification of such a regional solution is not
guaranteed.
'negative' : not applicable, PK_LOGICAL_false will be returned.
See Calculating minimum and maximum distance for more information.