CRATDF ( namlen, name, nopts, option, opdata, type, ifail )
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Create a new attribute type definition.
Receives:
KI_int_nitems *namlen --- length of 'name'
KI_chr_string name[namlen] --- name of attribute type
KI_int_nitems *nopts --- number of option codes
KI_cod_atop option[nopts] --- array of option codes
<KI_tag_list> opdata[nopts] --- corresponding lists of data
Returns:
KI_tag_attrib_def *type --- attribute type
KI_cod_error *ifail --- error code
Specific errors:
KI_illegal_owner invalid class for type with geometric owner
KI_not_found legal owner option has been omitted
class code has been omitted
no legal owners supplied
KI_bad_request_code invalid class code supplied
list of field types contains an invalid code
KI_list_wrong_length class code list length is not one
KI_not_unique a token has been repeated in 'option'
KI_wrong_entity_in_list invalid token found in list of legal owners
KI_duplicate_list_item item duplicated in list of legal owners
KI_existing_attr_type attribute type already defined
KI_bad_name invalid name for attribute type
Description:
Creates a new attribute type definition with the given name, returning
the tag of the type for use in calling the other attribute functions.
The attribute type definition comes in two parts; the name, which will
act as a label for the type which is fixed across transmit and receive,
and the option data, which specify what entities may own attributes of
the given type, what fields these attributes have and how such attributes
behave when modelling operations are applied to their owners.
Type name:
The name is specified by a character array containing only printable
characters and an integer argument stating the length of the name.
If 'name' begins with the string SDL/TY, which is reserved for attribute
types whose names are generated internally by Parasolid, KI_bad_name will
be returned in 'ifail'.
Option data:
The data defining the attribute type are supplied in the arrays 'option'
and 'opdata'. Each entry in 'option' is a code from the sequence ATOP00.
The entries in 'opdata' are tags of lists of data appropriate to the codes
in the corresponding positions in 'option'.
The following table lists the legal 'option' values and the corresponding
data; the first two codes must be supplied to specify the legal owners
and behaviour when modelling operations are applied to the owner of an
attribute:
token option[i] | data in list opdata[i]
ATOPCL | RQAC (class) code indicating behaviour when owner changes
ATOPOW | legal owner type codes
ATOPFL | field types
Field types:
Every attribute of a certain type contains a specified sequence of fields
of specified types; these are supplied to CRATDF as request codes in an
integer list in the position in array 'opdata' corresponding to that of
the entry ATOPFL in the array 'option'. The permitted tokens and their
meanings are as follows:
RQAPRL Real
RQAPIN Integer
RQAPCS Character string
RQAPVC Vector
RQAPCO Co-ordinate
RQAPDR Direction
RQAPAX Axis
An axis field consists of two vector values, communicated as six real
values, one of which is a point on the axis and the other is its direction.
The order of the fields is important, as they are distinguished in OUATDF,
CREATT and OUTATT by type and order.
To define an attribute which has no fields, omit ATOPFL in 'option'.
Class code:
The behaviour of an attribute of the new type when the entity to which
the attribute is attached is changed by a modelling operation is described
by the request code supplied in 'opdata' alongside the code ATOPCL in
'option'. The meaning of the request code alongside ATOPCL is as follows:
RQAC01 Attribute is independent of physical size and position of
entity to which it is attached (e.g. density).
RQAC02 Attribute is dependent on entity size but not on position.
(e.g. weight).
RQAC03 Attribute may vary with position or orientation (e.g. moment
of inertia).
RQAC04 Attribute transforms with its owner, but is otherwise
independent of the size and shape of its owner (e.g.
start-point or direction of movement of the tool that
cuts a face)
RQAC05 Attribute transforms with its owner provided its owner is
not changed in other ways (e.g. centre of gravity)
RQAC06 As for class 1, attribute is independent of physical size and
position of the entity to which it is attached. However this
class of attribute supports multiple values - one entity may
have a list of attributes of the same type attached.
RQAC07 As for class 4, attribute transforms with its owner, but is
otherwise independent of size and shape of the owner. However
this class supports multiple values - an entity may have a list
of attributes of the same type attached.
The response of a field of an attribute when the attribute transforms
(with its owner) depends on the type of the field as follows:
real, integer and string fields are unaffected,
co-ordinate fields are acted on by the transformation,
vector and direction fields are acted on by the reflection and rotation
parts of the transformation, and
axis fields behave as a coordinate field and a direction field.
For a fuller account of the behaviour of attributes under modelling
operations and the meaning of attributes, consult the chapter on Attributes.
Legal owners:
The entities which may legitimately own attributes of the given type
are specified in an integer list, passed in 'opdata' in the position
corresponding to that of the code ATOPOW in 'option', using the following
token values to identify the different entity types:
TYTOAS Assembly
TYTOIN Instance
TYTOBY Body
TYTORG Region
TYTOSH Shell
TYTOFA Face
TYTOLO Loop
TYTOED Edge
TYTOVX Vertex
TYADFE Feature
TYGESU Surface
TYGECU Curve
TYGEPT Point
The geometric entity types, surface, curve and point, may only be specified
as legal owners for attribute types with class RQAC01 or RQAC04.
