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Application module:
Geometrically bounded surface |
ISO/TS 10303-1507:2018-11(E)
© ISO
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This clause specifies the information requirements for the
Geometrically bounded surface
application module. The information requirements are specified as the
Application Reference Model (ARM) of this application module.
NOTE 1 A graphical representation of the information
requirements is given in
Annex C.
NOTE 2 The mapping specification is specified in
5.1. It shows how
the information requirements are met by using common resources and
constructs defined or imported in the MIM schema of this application
module.
This clause defines the information requirements to which implementations shall
conform using the EXPRESS language as defined in ISO 10303-11.
The following begins the
Geometrically_bounded_surface_arm
schema and identifies the necessary external references.
EXPRESS specification:
*)
SCHEMA Geometrically_bounded_surface_arm;
(*
The following EXPRESS interface statements specify the elements
imported from the ARMs of other application modules.
EXPRESS specification:
*)
USE FROM
Basic_curve_arm;
--
ISO/TS 10303-1651
USE FROM
B_spline_geometry_arm;
--
ISO/TS 10303-1801
(*
NOTE 1
The schemas referenced above are specified in the following
part of ISO 10303:
| Basic_curve_arm |
ISO/TS 10303-1651 |
| B_spline_geometry_arm |
ISO/TS 10303-1801 |
NOTE 2
See Annex C,
Figures
C.1and C.2
for a graphical representation of this schema.
This subclause specifies the ARM type
for this application module. The ARM type and
definition is specified below.
A SELECT type defining the types of elements that are to be used in the definition of a Geometrically_bounded_surface_shape_representation
EXPRESS specification:
*)
TYPE
geometrically_bounded_surface_shape_representation_item =
SELECT
(Axis_placement_3d,
Geometric_placement_operation,
Surface_set);
END_TYPE;
(*
This subclause specifies the ARM entities for this
module. Each ARM application entity is an atomic element that
embodies a unique application concept and contains attributes
specifying the data elements of the entity. The ARM
entities and definitions are specified below.
A Boundary_curve is a type of Closed_composite_curve that lies on a surface and is suitable for the definition of a surface boundary.
NOTE 1
This entity is incompletely modelled in the ARM. Complete specification
can be obtained in the definition of the corresponding MIM entity.
NOTE 2
The corresponding MIM entity has an inherited derived attribute identifying the surface, or surfaces, on which the Boundary_curve lies.
EXPRESS specification:
*)
ENTITY Boundary_curve
SUBTYPE OF (Closed_composite_curve);
END_ENTITY;
(*
A Curve_bounded_surface is a type of Bounded_surface with explicit geometric boundaries defined by curves lying on the surface.
NOTE 1
This entity is incompletely modelled in the ARM. Complete specification
can be obtained in the definition of the corresponding MIM entity.
NOTE 2
The corresponding MIM entity has additional WHERE rules to ensure that the boundary curves all lie on the basis_surface and are correctly defined.
EXPRESS specification:
*)
ENTITY Curve_bounded_surface
SUBTYPE OF (Bounded_surface);
basis_surface : Surface;
boundaries : SET[1:?] OF Boundary_curve;
implicit_outer : BOOLEAN;
WHERE
WR1: (NOT(implicit_outer)) OR
('BASIC_GEOMETRY_ARM.BOUNDED_SURFACE' IN TYPEOF(basis_surface));
END_ENTITY;
(*
Attribute definitions:
basis_surface:
the surface to be bounded.
boundaries:
the complete set of Boundary_curves of the surface other than the implicit outer boundary.
NOTE 3
The implicit boundary need not be present.
implicit_outer:
a BOOLEAN flag which, if true, indicates the natural boundary of the surface is used as
an outer boundary.
Formal propositions:
WR1:
the outer boundary shall only be implicitly defined if the basis_surface is bounded.
A Geometrically_bounded_surface_shape_representation is a type of Geometric_model
that consists of one or many surface models defined as Surface_sets, and transformations, if needed.
All surfaces, and curves used in their definition, shall be explicitly trimmed. The boundaries of surfaces shall be defined
by Boundary_curves
NOTE 1
This entity is incompletely modelled in the ARM. Complete specification
can be obtained in the definition of the corresponding MIM entity.
EXPRESS specification:
*)
ENTITY Geometrically_bounded_surface_shape_representation
SUBTYPE OF (Geometric_model);
SELF\Representation.items : SET[1:?] OF geometrically_bounded_surface_shape_representation_item;
END_ENTITY;
(*
Attribute definitions:
items:
a collection of
geometrically_bounded_surface_shape_representation_items
of the Geometrically_bounded_surface_shape_representation. An item is a Surface_set, an Axis_placement_3d,
or a Geometric_placement_operation
NOTE 2
When a Geometric_placement_operation is included there are
rules in the corresponding MIM entity to ensure that it is mapping a Geometrically_bounded_surface_shape_representation.
NOTE 3
Duplicates are not allowed in a set.
NOTE 4
The set shall not be empty.
A Surface_set is a type of Detailed_geometric_model_element
that consists of one or many surfaces used to define a surface model.
EXPRESS specification:
*)
ENTITY Surface_set
SUBTYPE OF (Detailed_geometric_model_element);
surface_elements : SET[1:?] OF Surface;
END_ENTITY;
(*
Attribute definitions:
surface_elements:
a collection of
Surfaces
contained in the Surface_set.
NOTE 1
Duplicates are not allowed in a set.
NOTE 2
The set shall not be empty.
*)
END_SCHEMA; -- Geometrically_bounded_surface_arm
(*
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