Class TIfcGridPlacement

Description

Hierarchy

Methods

Properties

Unit

CastleIfc

Declaration

type TIfcGridPlacement = class(TIfcObjectPlacement)

Description

IFC class IfcGridPlacement.

Source: scene/load/ifc/castleifc_ifc_standard_types_autogenerated.inc (line 316).

Hierarchy

TObject
TPersistent
TComponent
TIfcPersistent
TIfcObjectPlacement
TIfcGridPlacement

Show Additional Members: Inherited Protected

Overview

Methods

Protected	`function WantsGlobalId: Boolean; virtual;`
Protected	`class function IfcClassName: String; virtual;`
Public	`constructor Create(AOwner: TComponent); override;`
Public	`destructor Destroy; override;`
Public	`function BuildNode(const Mapping: TCastleIfcMapping): TTransformNode;`
Public	`procedure UpdateNode(const Mapping: TCastleIfcMapping; const Transform: TTransformNode); virtual;`

Properties

Published	`property GlobalId: String read FGlobalId write FGlobalId;`
Published	`property PlacementRelTo: TIfcObjectPlacement read FPlacementRelTo write FPlacementRelTo;`
Published	`property PlacesObject: TIfcProductList read FPlacesObject;`
Published	`property ReferencedByPlacements: TIfcObjectPlacementList read FReferencedByPlacements;`

Description

Methods

Protected function WantsGlobalId: Boolean; virtual;

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_types.inc (line 52).

Protected class function IfcClassName: String; virtual;

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).

Public constructor Create(AOwner: TComponent); override;

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2762).

Public destructor Destroy; override;

This item has no description.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2763).

Public function BuildNode(const Mapping: TCastleIfcMapping): TTransformNode;

Build TTransformNode representing this TIfcObjectPlacement.

This is not used for TIfcObjectPlacement that are directly referenced by TIfcObjectDefinition, in which case TIfcObjectDefinition creates TTransformNode, and only calls our UpdateNode to set it's parameters.

This is used for TIfcObjectPlacement instances that are not directly referenced by TIfcObjectDefinition (but may be still useful, e.g. as placementRelTo targets for other TIfcObjectPlacement instances).

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2774).

Public procedure UpdateNode(const Mapping: TCastleIfcMapping; const Transform: TTransformNode); virtual;

Update the TTransformNode with the transformation expressed by this TIfcObjectPlacement (local transformation, not accounding for any transformation implied by PlacementRelTo).

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2779).

Properties

Published property GlobalId: String read FGlobalId write FGlobalId;

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 PlacementRelTo: TIfcObjectPlacement read FPlacementRelTo write FPlacementRelTo;

Reference to object placement that provides the relative placement with its placement in a grid, local coordinate system or linear referenced placement.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2785).

Published property PlacesObject: TIfcProductList read FPlacesObject;

The IfcObjectPlacement shall be used to provide a placement and an object coordinate system for instances of IfcProduct.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2789).

Published property ReferencedByPlacements: TIfcObjectPlacementList read FReferencedByPlacements;

Inverse of PlacementRelTo.

Source: scene/load/ifc/castleifc_ifc_standard_types.inc (line 2792).

Generated by PasDoc 0.17.0.snapshot.