Class TIfcGeometricRepresentationSubContext

Description
Hierarchy
Constants
Methods
Properties

Unit

CastleIfc

Declaration

type TIfcGeometricRepresentationSubContext = class(TIfcGeometricRepresentationContext)

Description

Context that applies to several shape representations of a product being a sub context, sharing the WorldCoordinateSystem, CoordinateSpaceDimension, Precision and TrueNorth attributes with the parent IfcGeometricRepresentationContext.

Descends from TIfcGeometricRepresentationContext, like in the IFC spec. The WorldCoordinateSystem, CoordinateSpaceDimension, Precision and TrueNorth are derived (from ParentContext) in a subcontext, so they are not stored in IFC files.

Spec: https://standards.buildingsmart.org/IFC/RELEASE/IFC4_3/HTML/lexical/IfcGeometricRepresentationSubContext.htm

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5139).

Hierarchy

Show Additional Members:

Overview

Constants

Public TypeModel = 'Model';
Public TypePlan = 'Plan';
Public TypeNotDefined = 'NotDefined';

Methods

Protected class function IfcClassName: String; virtual;
Protected function WantsGlobalId: Boolean; override;
Public constructor Create(AOwner: TComponent); override;
Public destructor Destroy; override;

Properties

Published property GlobalId: String read FGlobalId write FGlobalId;
Published property ContextIdentifier: TIfcLabel read FContextIdentifier write FContextIdentifier;
Published property ContextType: TIfcLabel read FContextType write FContextType;
Published property RepresentationsInContext: TIfcRepresentationList read FRepresentationsInContext;
Published property HasSubContexts: TIfcGeometricRepresentationSubContextList read FHasSubContexts;
Published property HasCoordinateOperation: TIfcCoordinateOperation read FHasCoordinateOperation write FHasCoordinateOperation;
Published property CoordinateSpaceDimension stored false;
Published property Precision stored false;
Published property WorldCoordinateSystem stored false;
Published property TrueNorth stored false;
Published property ParentContext: TIfcGeometricRepresentationContext read FParentContext write FParentContext;
Published property TargetScale: TIfcPositiveRatioMeasure read FTargetScale write FTargetScale;
Published property TargetView: TIfcGeometricProjectionEnum read FTargetView write FTargetView;
Published property UserDefinedTargetView: TIfcLabel read FUserDefinedTargetView write FUserDefinedTargetView;

Description

Constants

Public TypeModel = 'Model';

This item is declared in ancestor TIfcGeometricRepresentationContext.

The following values for ContextType are limited to these 3 constants for TIfcGeometricRepresentationContext.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5087).

Public TypePlan = 'Plan';

This item is declared in ancestor TIfcGeometricRepresentationContext.

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5088).

Public TypeNotDefined = 'NotDefined';

This item is declared in ancestor TIfcGeometricRepresentationContext.

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5089).

Methods

Protected class function IfcClassName: String; virtual;

This item is declared in ancestor TIfcPersistent.

Name for the IFC standard, used in IFC files. By default, this is just ClassName with prefix 'T' removed.

Source: scene/load/ifc/castleifc_ifc_types.inc (line 56).

Protected function WantsGlobalId: Boolean; override;

This item is declared in ancestor TIfcGeometricRepresentationContext.

This item has no description. Showing description inherited from TIfcPersistent.WantsGlobalId.

If True, instances of this class will have GlobalId auto-assigned at saving, and they will be saved as part of the "data" list in IFC JSON files.

Strictly following the spec, this should be only defined for TIfcRoot, because only IfcRoot has GlobalId. In reality, we need GlobalId at TIfcPersistent to load some files, and we sometimes need WantsGlobalId = True to save some files.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5082).

Public constructor Create(AOwner: TComponent); override;

This item is declared in ancestor TIfcGeometricRepresentationContext.

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5090).

Public destructor Destroy; override;

This item is declared in ancestor TIfcGeometricRepresentationContext.

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5091).

Properties

Published property GlobalId: String read FGlobalId write FGlobalId;

This item is declared in ancestor TIfcPersistent.

Globally unique identifier for the object instance.

Note: Not declared as TGUID, because TGUID cannot be published, but also we don't really need it: for our purposes, this identifier is just an arbitrary string.

Note: IFC 4.3 specification puts this only at IfcRoot, not at every IFC class. But testcase https://github.com/buildingsmart-community/Community-Sample-Test-Files/blob/main/IFC%204.0.2.1%20(IFC%204)/ISO%20Spec%20archive/wall-with-opening-and-window.json (from IFC 4.0) shows this can be present at any IFC class, in particular TIfcGeometricRepresentationContext.

In fact, TIfcGeometricRepresentationContext needs to have GlobalId to be successfully saved (avoid recursively trying to serialize it) in some cases. We indicate such classes with WantsGlobalId.

IFC JSON documentation says this, which seems to (unfortunately it is not unambiguous enough...) allow this at any IFC class: "Whereas the globalId attribute is only available to those elements that are descendent of the IfcRoot entity in the EXPRESS schema, we encourage a broader use of this globalId, to enable referencing between objects in a JSON file when useful.".

Source: scene/load/ifc/castleifc_ifc_types.inc (line 79).

Published property ContextIdentifier: TIfcLabel read FContextIdentifier write FContextIdentifier;

This item is declared in ancestor TIfcRepresentationContext.

The optional identifier of the representation context as used within a project.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5060).

Published property ContextType: TIfcLabel read FContextType write FContextType;

This item is declared in ancestor TIfcRepresentationContext.

The description of the type of a representation context. The supported values for context type are to be specified by implementers agreements.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5064).

Published property RepresentationsInContext: TIfcRepresentationList read FRepresentationsInContext;

This item is declared in ancestor TIfcRepresentationContext.

All shape representations that are defined in the same representation context.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5067).

Published property HasSubContexts: TIfcGeometricRepresentationSubContextList read FHasSubContexts;

This item is declared in ancestor TIfcGeometricRepresentationContext.

The set of IfcGeometricRepresentationSubContexts that refer to this IfcGeometricRepresentationContext.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5110).

Published property HasCoordinateOperation: TIfcCoordinateOperation read FHasCoordinateOperation write FHasCoordinateOperation;

This item is declared in ancestor TIfcGeometricRepresentationContext.

Indicates conversion between coordinate systems.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5113).

Published property CoordinateSpaceDimension stored false;

Derived from ParentContext in a subcontext, so not stored.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5147).

Published property Precision stored false;

Derived from ParentContext in a subcontext, so not stored.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5149).

Published property WorldCoordinateSystem stored false;

Derived from ParentContext in a subcontext, so not stored.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5151).

Published property TrueNorth stored false;

Derived from ParentContext in a subcontext, so not stored.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5153).

Published property ParentContext: TIfcGeometricRepresentationContext read FParentContext write FParentContext;

Parent context from which the sub context derives its world coordinate system, precision, space coordinate dimension and true north.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5157).

Published property TargetScale: TIfcPositiveRatioMeasure read FTargetScale write FTargetScale;

The target plot scale of the representation to which this representation context applies.

NOTE Scale indicates the target plot scale for the representation sub context, all annotation styles are given in plot dimensions according to this target plot scale. If multiple instances of IfcGeometricRepresentationSubContext are given having the same TargetView value, the target plot scale applies up to the next smaller scale, or up to unlimited small scale.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5168).

Published property TargetView: TIfcGeometricProjectionEnum read FTargetView write FTargetView;

Target view of the representation to which this representation context applies.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5171).

Published property UserDefinedTargetView: TIfcLabel read FUserDefinedTargetView write FUserDefinedTargetView;

User defined target view, this attribute value shall be given, if the TargetView attribute is set to TIfcGeometricProjectionEnum.UserDefined.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 5175).

Generated by PasDoc 1.0.4.

Copyright Michalis Kamburelis and Castle Game Engine Contributors.

This webpage is also open-source and we welcome pull requests to improve it.

We use cookies for analytics. See our privacy policy.