Abstract base class for named attribute layers. More...

#include <BRepGraph_Layer.hxx>

Inheritance diagram for BRepGraph_Layer:

[legend]

Public Member Functions
virtual const Standard_GUID &	ID () const =0
	Layer type identity (unique within a graph).

virtual const TCollection_AsciiString &	Name () const =0
	Layer identity (unique within a graph).

virtual void	OnNodeRemoved (const BRepGraph_NodeId theNode) noexcept
	Called when a node is soft-removed without a replacement.

void	OnItemRemoved (const BRepGraph_ItemId theItem) noexcept
	Dispatch a generic item removal to the matching typed removal callback. This is a non-virtual convenience entry point; typed callbacks remain the extension points for derived layers.

virtual void	OnNodeReplaced (const BRepGraph_NodeId theOldNode, const BRepGraph_NodeId theNewNode) noexcept
	Called when a node is soft-removed and replaced by another node.

virtual void	CopyTo (const BRepGraph_CopyRemap &theCopy) const =0
	Copy this source layer data into another graph. The source graph is the graph this layer is attached to (Graph()).

virtual void	InvalidateAll () noexcept=0
	Mark all cached values dirty (bulk invalidation).

virtual void	Clear () noexcept=0
	Clear all stored data.

virtual int	SubscribedKinds () const
	Return a bitmask of BRepGraph_NodeId::Kind values this layer subscribes to. Only modification events matching subscribed kinds are dispatched. Default: 0 (no subscription - no modification events received). Override to receive OnNodeModified/OnNodesModified callbacks. The returned value must be constant for the lifetime of the layer.

virtual void	OnNodeModified (const BRepGraph_NodeId theNode) noexcept
	Called in immediate (non-deferred) mode after a single node is modified. Only dispatched if the node's kind matches SubscribedKinds(). Default: no-op.

void	OnItemModified (const BRepGraph_ItemId theItem) noexcept
	Dispatch a generic item modification to the matching typed modification callback. This is a non-virtual convenience entry point; typed callbacks remain the extension points for derived layers.

virtual void	OnNodesModified (const NCollection_Array1< BRepGraph_NodeId > &theModifiedNodes) noexcept
	Called after EndDeferredInvalidation() with all nodes modified during the deferred scope. Only dispatched if at least one modified node's kind matches SubscribedKinds(). The array may contain nodes of kinds not subscribed to - layers should filter internally if needed. Default: no-op.

virtual int	SubscribedRefKinds () const
	Return a bitmask of BRepGraph_RefId::Kind values this layer subscribes to. Only modification events matching subscribed ref kinds are dispatched. Default: 0 (no subscription). Must be constant for the layer's lifetime.

virtual void	OnRefRemoved (const BRepGraph_RefId theRef) noexcept
	Called when a reference is soft-deleted via RemoveRef(). No replacement concept - refs are simply removed (unlike nodes which can have a replacement during sewing or deduplication). Dispatched to all layers regardless of SubscribedRefKinds(). Default: no-op.

virtual void	OnRefModified (const BRepGraph_RefId theRef) noexcept
	Called in immediate (non-deferred) mode after a single ref is mutated. Only dispatched if the ref's kind matches SubscribedRefKinds(). Default: no-op.

virtual void	OnRefsModified (const NCollection_Array1< BRepGraph_RefId > &theModifiedRefs) noexcept
	Called after EndDeferredInvalidation() with all refs modified during the deferred scope. Only dispatched if at least one modified ref's kind matches SubscribedRefKinds(). The array may contain refs of kinds not subscribed to - layers should filter internally if needed. Default: no-op.

uint64_t	Revision () const noexcept
	Monotonic revision counter incremented by touch() on every observable state change. Consumers compare stored revisions to detect staleness in O(1). Derived layers MUST call touch() from their mutators.

Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.

	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.

Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.

virtual	~Standard_Transient ()=default
	Destructor must be virtual.

virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.

bool	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.

bool	IsInstance (const char *const theTypeName) const
	Returns a true value if this is an instance of TypeName.

bool	IsKind (const opencascade::handle< Standard_Type > &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism.

bool	IsKind (const char *const theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism.

Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.

int	GetRefCount () const noexcept
	Get the reference counter of this object.

void	IncrementRefCounter () noexcept
	Increments the reference counter of this object. Uses relaxed memory ordering since incrementing only requires atomicity, not synchronization with other memory operations.

int	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value. Uses release ordering for the decrement to ensure all writes to the object are visible before the count reaches zero. An acquire fence is added only when the count reaches zero, ensuring proper synchronization before deletion. This is more efficient than using acq_rel for every decrement.

virtual void	Delete () const
	Memory deallocator for transient classes.

Static Public Member Functions
static int	KindBit (const BRepGraph_NodeId::Kind theKind)
	Convenience: return bitmask bit for a given Kind.

static int	RefKindBit (const BRepGraph_RefId::Kind theKind)
	Convenience: return bitmask bit for a given RefId::Kind.

Static Public Member Functions inherited from Standard_Transient
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.

static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.

Protected Member Functions
	BRepGraph_Layer ()

void	touch () noexcept
	Bump the revision counter.

bool	IsAttached () const noexcept
	True while this layer is registered in a live graph registry.

const BRepGraph &	Graph () const
	Attached graph for read-only layer services. Raises Standard_ProgramError if detached.

BRepGraph *	AttachedGraph () const noexcept
	Attached mutable graph for graph-owned service layers. Returns null if detached.

virtual void	OnAttached () noexcept
	Called after the layer is attached to a graph registry.

virtual void	OnDetached () noexcept
	Called before the layer is detached from a graph registry.

Static Protected Member Functions
template<BRepGraph_NodeId::Kind TheKind>
static BRepGraph_NodeId::Typed< TheKind >	RemappedItem (const BRepGraph_CopyRemap &theCopy, const BRepGraph_NodeId::Typed< TheKind > theId)

template<BRepGraph_RefId::Kind TheKind>
static BRepGraph_RefId::Typed< TheKind >	RemappedItem (const BRepGraph_CopyRemap &theCopy, const BRepGraph_RefId::Typed< TheKind > theId)

Additional Inherited Members
Public Types inherited from Standard_Transient
typedef void	base_type
	Returns a type descriptor about this object.

Detailed Description

Abstract base class for named attribute layers.

A layer groups per-node and per-reference metadata under a unique name with lifecycle callbacks. Layers are registered on BRepGraph and automatically notified when nodes or references are removed, remapped (compact), or modified.

Derived layers store domain-specific data (names, colors, materials, etc.) in internal maps keyed by BRepGraph_NodeId or BRepGraph_RefId. The lifecycle callbacks ensure data consistency across all graph mutations.

Node Modification Events

Layers subscribe to node modification events by overriding SubscribedKinds() to return a non-zero bitmask of Kind values. When a subscribed node kind is modified, OnNodeModified() (immediate mode) or OnNodesModified() (deferred batch mode) is called. Layers with SubscribedKinds() == 0 (default) incur zero dispatch overhead.

Reference Modification Events

Layers subscribe to reference modification events by overriding SubscribedRefKinds() to return a non-zero bitmask of BRepGraph_RefId::Kind values. When a subscribed ref kind is mutated, OnRefModified() (immediate mode) or OnRefsModified() (deferred batch mode) is called. Removal is always dispatched via OnRefRemoved() regardless of subscription.

Thread safety

Callback dispatch is single-threaded (called from mutation paths). Layers that only provide read access can skip internal locking.

Warning: All lifecycle callbacks are declared noexcept. Derived implementations that throw will cause std::terminate. This is enforced by C++ language semantics for noexcept virtual overrides.

Constructor & Destructor Documentation

◆ BRepGraph_Layer()

BRepGraph_Layer::BRepGraph_Layer ( )

protected

Member Function Documentation

◆ AttachedGraph()

BRepGraph * BRepGraph_Layer::AttachedGraph ( ) const

inlineprotectednoexcept

Attached mutable graph for graph-owned service layers. Returns null if detached.

◆ Clear()

virtual void BRepGraph_Layer::Clear ( )

pure virtualnoexcept

Clear all stored data.

Implemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ CopyTo()

virtual void BRepGraph_Layer::CopyTo ( const BRepGraph_CopyRemap & theCopy ) const

pure virtual

Copy this source layer data into another graph. The source graph is the graph this layer is attached to (Graph()).

Parameters

[in] theCopy source graph, target graph, and source item id -> target item id remap

Note: Missing source items were not copied; persistent layers should skip dependent records.; For BRepGraph_CopyRemap::Mode::Compact, the layer is being migrated in-place after structural compaction. UID/ItemUID records and ref/rep entries should be remapped through the item map. Stale entries (absent from the remap) should be dropped.

Warning: This callback may allocate and is intentionally not noexcept.

Implemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ Graph()

const BRepGraph & BRepGraph_Layer::Graph ( ) const

protected

Attached graph for read-only layer services. Raises Standard_ProgramError if detached.

◆ ID()

virtual const Standard_GUID & BRepGraph_Layer::ID ( ) const

pure virtual

Layer type identity (unique within a graph).

Implemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ InvalidateAll()

virtual void BRepGraph_Layer::InvalidateAll ( )

pure virtualnoexcept

Mark all cached values dirty (bulk invalidation).

Implemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ IsAttached()

bool BRepGraph_Layer::IsAttached ( ) const

inlineprotectednoexcept

True while this layer is registered in a live graph registry.

◆ KindBit()

static int BRepGraph_Layer::KindBit ( const BRepGraph_NodeId::Kind theKind )

inlinestatic

Convenience: return bitmask bit for a given Kind.

◆ Name()

virtual const TCollection_AsciiString & BRepGraph_Layer::Name ( ) const

pure virtual

Layer identity (unique within a graph).

Implemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ OnAttached()

virtual void BRepGraph_Layer::OnAttached ( )

protectedvirtualnoexcept

Called after the layer is attached to a graph registry.

◆ OnDetached()

virtual void BRepGraph_Layer::OnDetached ( )

protectedvirtualnoexcept

Called before the layer is detached from a graph registry.

◆ OnItemModified()

void BRepGraph_Layer::OnItemModified ( const BRepGraph_ItemId theItem )

noexcept

Dispatch a generic item modification to the matching typed modification callback. This is a non-virtual convenience entry point; typed callbacks remain the extension points for derived layers.

Parameters

[in] theItem the modified definition or reference

◆ OnItemRemoved()

void BRepGraph_Layer::OnItemRemoved ( const BRepGraph_ItemId theItem )

noexcept

Dispatch a generic item removal to the matching typed removal callback. This is a non-virtual convenience entry point; typed callbacks remain the extension points for derived layers.

Parameters

[in] theItem the removed definition or reference

◆ OnNodeModified()

virtual void BRepGraph_Layer::OnNodeModified ( const BRepGraph_NodeId theNode )

virtualnoexcept

Called in immediate (non-deferred) mode after a single node is modified. Only dispatched if the node's kind matches SubscribedKinds(). Default: no-op.

Parameters

[in] theNode the modified node

◆ OnNodeRemoved()

virtual void BRepGraph_Layer::OnNodeRemoved ( const BRepGraph_NodeId theNode )

virtualnoexcept

Called when a node is soft-removed without a replacement.

Parameters

[in] theNode the removed node Layers should discard or archive data associated with it.

Warning: Layer callbacks must not throw. They are called from noexcept notification paths (MutGuard destructors, deferred invalidation flush).

Reimplemented in BRepGraph_LayerDeferred, BRepGraph_LayerHistory, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ OnNodeReplaced()

virtual void BRepGraph_Layer::OnNodeReplaced	(	const BRepGraph_NodeId	theOldNode,
		const BRepGraph_NodeId	theNewNode )

virtualnoexcept

Called when a node is soft-removed and replaced by another node.

Parameters

[in]	theOldNode	the removed node
[in]	theNewNode	the node that replaces theOldNode Layers that store node-keyed data should migrate from theOldNode to theNewNode when the replacement kind is compatible. This is a structural lifecycle event, not an algorithmic history record.

Warning: Layer callbacks must not throw. They are called from noexcept notification paths (MutGuard destructors, deferred invalidation flush).

Reimplemented in BRepGraph_LayerDeferred, BRepGraph_LayerLock, and BRepGraph_LayerTopoSupplement.

◆ OnNodesModified()

virtual void BRepGraph_Layer::OnNodesModified ( const NCollection_Array1< BRepGraph_NodeId > & theModifiedNodes )

virtualnoexcept

Called after EndDeferredInvalidation() with all nodes modified during the deferred scope. Only dispatched if at least one modified node's kind matches SubscribedKinds(). The array may contain nodes of kinds not subscribed to - layers should filter internally if needed. Default: no-op.

Parameters

[in] theModifiedNodes all modified, non-removed nodes

◆ OnRefModified()

virtual void BRepGraph_Layer::OnRefModified ( const BRepGraph_RefId theRef )

virtualnoexcept

Called in immediate (non-deferred) mode after a single ref is mutated. Only dispatched if the ref's kind matches SubscribedRefKinds(). Default: no-op.

Parameters

[in] theRef the modified reference

◆ OnRefRemoved()

virtual void BRepGraph_Layer::OnRefRemoved ( const BRepGraph_RefId theRef )

virtualnoexcept

Called when a reference is soft-deleted via RemoveRef(). No replacement concept - refs are simply removed (unlike nodes which can have a replacement during sewing or deduplication). Dispatched to all layers regardless of SubscribedRefKinds(). Default: no-op.

Parameters

[in] theRef the removed reference

Reimplemented in BRepGraph_LayerDeferred, and BRepGraph_LayerLock.

◆ OnRefsModified()

virtual void BRepGraph_Layer::OnRefsModified ( const NCollection_Array1< BRepGraph_RefId > & theModifiedRefs )

virtualnoexcept

Called after EndDeferredInvalidation() with all refs modified during the deferred scope. Only dispatched if at least one modified ref's kind matches SubscribedRefKinds(). The array may contain refs of kinds not subscribed to - layers should filter internally if needed. Default: no-op.

Parameters

[in] theModifiedRefs all modified, non-removed refs

◆ RefKindBit()

static int BRepGraph_Layer::RefKindBit ( const BRepGraph_RefId::Kind theKind )

inlinestatic

Convenience: return bitmask bit for a given RefId::Kind.

◆ RemappedItem() [1/2]

template<BRepGraph_NodeId::Kind TheKind>

static BRepGraph_NodeId::Typed< TheKind > BRepGraph_Layer::RemappedItem	(	const BRepGraph_CopyRemap &	theCopy,
		const BRepGraph_NodeId::Typed< TheKind >	theId )

inlinestaticprotected

◆ RemappedItem() [2/2]

template<BRepGraph_RefId::Kind TheKind>

static BRepGraph_RefId::Typed< TheKind > BRepGraph_Layer::RemappedItem	(	const BRepGraph_CopyRemap &	theCopy,
		const BRepGraph_RefId::Typed< TheKind >	theId )

inlinestaticprotected

◆ Revision()

uint64_t BRepGraph_Layer::Revision ( ) const

inlinenoexcept

Monotonic revision counter incremented by touch() on every observable state change. Consumers compare stored revisions to detect staleness in O(1). Derived layers MUST call touch() from their mutators.

◆ SubscribedKinds()

virtual int BRepGraph_Layer::SubscribedKinds ( ) const

virtual

Return a bitmask of BRepGraph_NodeId::Kind values this layer subscribes to. Only modification events matching subscribed kinds are dispatched. Default: 0 (no subscription - no modification events received). Override to receive OnNodeModified/OnNodesModified callbacks. The returned value must be constant for the lifetime of the layer.

◆ SubscribedRefKinds()

virtual int BRepGraph_Layer::SubscribedRefKinds ( ) const

virtual

Return a bitmask of BRepGraph_RefId::Kind values this layer subscribes to. Only modification events matching subscribed ref kinds are dispatched. Default: 0 (no subscription). Must be constant for the layer's lifetime.

◆ touch()

void BRepGraph_Layer::touch ( )

inlineprotectednoexcept

Bump the revision counter.

The documentation for this class was generated from the following file:

BRepGraph_Layer.hxx

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Additional Inherited Members

Detailed Description

Node Modification Events

Reference Modification Events

Thread safety

Constructor & Destructor Documentation

◆ BRepGraph_Layer()

Member Function Documentation

◆ AttachedGraph()

◆ Clear()

◆ CopyTo()

◆ Graph()

◆ ID()

◆ InvalidateAll()

◆ IsAttached()

◆ KindBit()

◆ Name()

◆ OnAttached()

◆ OnDetached()

◆ OnItemModified()

◆ OnItemRemoved()

◆ OnNodeModified()

◆ OnNodeRemoved()

◆ OnNodeReplaced()

◆ OnNodesModified()

◆ OnRefModified()

◆ OnRefRemoved()

◆ OnRefsModified()

◆ RefKindBit()

◆ RemappedItem() [1/2]

◆ RemappedItem() [2/2]

◆ Revision()

◆ SubscribedKinds()

◆ SubscribedRefKinds()

◆ touch()