package limits

Import Path
	github.com/pancsta/d2/d2layouts/d2talalayout/internal/limits (on go.dev)

Dependency Relation
	imports 6 packages, and imported by 12 packages

Involved Source Files

	    arithmetic.go
	    optimization.go
	  d work.go
		Package limits provides the engine's topology ceilings and reusable work
		accounting primitives. It deliberately has no dependency on graph, layout,
		or routing types so every layout domain can consume the same limits without
		introducing package cycles.
Package-Level Type Names (total 2)

	/* sort by: alphabet | popularity */
	 type OptimizationWorkGuard (struct)
		OptimizationWorkGuard accounts one complete hierarchy or placement
		optimization. The limit is an explicit ceiling; zero permits cancellation
		checks but no charged work.

		Methods (total 8)
			(*OptimizationWorkGuard) Add(amount uint64) error
				Add charges amount optimization work units.

			(*OptimizationWorkGuard) AddProduct(a, b uint64) error
				AddProduct multiplies two work dimensions without allowing arithmetic
				overflow.

			(*OptimizationWorkGuard) AddSort(length int) error
				AddSort charges the comparison bound for sorting length values.

			(*OptimizationWorkGuard) Check() error
				Check observes optimization cancellation immediately.

			(*OptimizationWorkGuard) Finish() error
				Finish observes cancellation at an optimization boundary.

			(*OptimizationWorkGuard) Location() string
				Location returns the operation name used in diagnostics.

			(*OptimizationWorkGuard) Step() error
				Step charges one optimization work unit.

			(*OptimizationWorkGuard) Used() uint64
				Used returns the accepted work units.

		Implements (at least 2)
			*OptimizationWorkGuard : github.com/pancsta/d2/d2layouts/d2talalayout/internal/graphbounds.WorkStepper
			*OptimizationWorkGuard : github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.SharedWorkStepper
		As Outputs Of (at least one exported)
			func NewOptimizationWorkGuard(ctx context.Context, location string, limit uint64) (*OptimizationWorkGuard, error)
		As Inputs Of (at least one exported)
			func Shuffle[T](values []T, random *rand.Rand, guard *OptimizationWorkGuard) error

	 type WorkGuard (struct)
		WorkGuard accounts a complete operation's signed work units and polls its
		context at a fixed stride. The limit is an explicit non-negative ceiling;
		zero permits cancellation checks but no charged work.

		Methods (total 6)
			(*WorkGuard) Add(units int64) error
				Add records multiple work units as one accounting operation. It enforces
				Step's work limit and polls cancellation when the accepted charge reaches or
				crosses a Step polling boundary. On a positive-limit overflow, Used reports
				the first rejected unit even when a crossed boundary observes cancellation.

			(*WorkGuard) Check() error
				Check observes cancellation immediately. Step and Add use a bounded stride
				in hot loops, while callers use Check at explicit cancellation boundaries.

			(*WorkGuard) Finish() error
				Finish observes cancellation regardless of the current work count.

			(*WorkGuard) SetLimit(limit int64)
				SetLimit changes the ceiling without resetting already consumed work.

			(*WorkGuard) Step() error
				Step charges one work unit.

			(*WorkGuard) Used() int64
				Used returns the number of charged or first-rejected work units.

		Implements (at least 2)
			*WorkGuard : github.com/pancsta/d2/d2layouts/d2talalayout/internal/graphbounds.WorkStepper
			*WorkGuard : github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.SharedWorkStepper
		As Outputs Of (at least 3)
			func NewWorkGuard(ctx context.Context, location string, limit int64) (*WorkGuard, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.EnsureTransactionWorkGuard(ctx context.Context, location string) (context.Context, *WorkGuard, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.ExistingTransactionWorkGuard(ctx context.Context, location string) (*WorkGuard, bool, error)
		As Inputs Of (at least 15)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.BuildNodeToTreeForDeserialization(trees map[*layoutgraph.Node][]*layoutgraph.Tree, guard *WorkGuard) (map[*layoutgraph.Node]*layoutgraph.Tree, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.ContainerOrderForSerialization(graph *layoutgraph.Graph, guard *WorkGuard) ([]*layoutgraph.Node, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.ContextWithTransactionWorkGuard(ctx context.Context, guard *WorkGuard) context.Context
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Graph).AllDescendantNodesWithWorkGuard(node *layoutgraph.Node, includeClusterNodes bool, guard *WorkGuard) ([]*layoutgraph.Node, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Graph).ContainerRDFSOrder(root *layoutgraph.Node, guard *WorkGuard) ([]*layoutgraph.Node, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Graph).IsBadStateWithWorkGuard(node *layoutgraph.Node, graphState *layoutgraph.GraphState, ignoreContainerEscape bool, guard *WorkGuard) (bool, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Graph).NewRequestTransactionWithWorkGuard(ctx context.Context, guard *WorkGuard, options layoutgraph.TransactionOptions) (*layoutgraph.Transaction, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Graph).WouldOverlapWithWorkGuard(node *layoutgraph.Node, point *geo.Point, exceptions []*layoutgraph.Node, pairwiseExceptions map[*layoutgraph.Node]map[*layoutgraph.Node]struct{}, guard *WorkGuard) (bool, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*GraphState).OwnedNodes(g *layoutgraph.Graph, guard *WorkGuard) (map[*layoutgraph.Node]struct{}, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*GraphState).UpdateWithWorkGuard(g *layoutgraph.Graph, guard *WorkGuard) error
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Node).AllReachableNodesContext(includeContainers, includeNears, traverseTrees bool, ignore map[*layoutgraph.Node]struct{}, guard *WorkGuard) ([]*layoutgraph.Node, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.(*Node).ReachableNodesContext(shouldVisit func(*layoutgraph.Node) bool, includeContainers, includeNears, traverseTrees bool, ignore map[*layoutgraph.Node]struct{}, guard *WorkGuard) ([]*layoutgraph.Node, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.Nodes.BoundingBoxWithWorkGuard(guard *WorkGuard) (*geo.Point, *geo.Point, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.Nodes.CenterWithWorkGuard(guard *WorkGuard) (*geo.Point, error)
			func github.com/pancsta/d2/d2layouts/d2talalayout/internal/layoutgraph.Nodes.DistanceClustersWithWorkGuard(threshold float64, guard *WorkGuard) ([][]*layoutgraph.Node, error)


Package-Level Functions (total 5)

	 func CheckedAddUint64(a, b uint64) (uint64, bool)
		CheckedAddUint64 returns a+b and whether the sum fits in uint64.

	 func CheckedMulUint64(a, b uint64) (uint64, bool)
		CheckedMulUint64 returns a*b and whether the product fits in uint64.

	 func NewOptimizationWorkGuard(ctx context.Context, location string, limit uint64) (*OptimizationWorkGuard, error)
		NewOptimizationWorkGuard constructs a guard and observes cancellation before
		any optimization work begins.

	 func NewWorkGuard(ctx context.Context, location string, limit int64) (*WorkGuard, error)
		NewWorkGuard constructs a work guard and observes cancellation before any
		operation work begins.

	 func Shuffle[T](values []T, random *rand.Rand, guard *OptimizationWorkGuard) error

		Type Parameters:
			T: any

		Shuffle is math/rand.Shuffle's Fisher-Yates implementation with a guard
		check before every random draw. Its reduction algorithm and draw order are
		intentionally identical so seeded layout output remains stable.


Package-Level Variables (only one)

	  var ErrOptimizationResourceLimit error
		ErrOptimizationResourceLimit reports exhausted or overflowing optimization
		work accounting.


Package-Level Constants (total 12)

	const MaxBinPackWorkUnits int64 = 1000000000
		MaxBinPackWorkUnits spans the complete recursive bin-packing operation,
		including speculative transactions and route scans.

	const MaxEngineEdges = 50000
		MaxEngineEdges is the largest edge count the engine processes in one attempt.

	const MaxEngineNodes = 10000
		MaxEngineNodes is the largest node count the engine processes in one attempt.

	const MaxEngineRoutePoints = 1000000
		MaxEngineRoutePoints bounds aggregate route storage throughout the engine.

	const MaxEngineTreeDepth = 256
		MaxEngineTreeDepth bounds recursive topology throughout the engine.

	const MaxEngineWorkUnits int64 = 61440000
		MaxEngineWorkUnits is the default aggregate work budget for a graph.

	const MaxGraphSize = 30000
		MaxGraphSize is the maximum supported width or height at a pipeline stage
		boundary.

	const MaxLabelPlacementWorkUnits int64 = 50000000
		MaxLabelPlacementWorkUnits bounds the quadratic overlap and candidate
		search performed while positioning labels and icons.

	const MaxOptimizationWorkUnits uint64 = 250000000
		MaxOptimizationWorkUnits bounds one hierarchy or placement optimization.

	const MaxPlaceTreesWorkUnits int64 = 68000000
		MaxPlaceTreesWorkUnits is calibrated for the superlinear candidate and
		obstacle work performed by tree placement.

	const MaxTransactionOverlapReferences int64 = 4000000
		MaxTransactionOverlapReferences bounds retained existing-overlap
		references. Exceptions are retained in both directions because hot
		placement checks key by the moved node.

	const MaxTransactionWorkUnits int64 = 1000000000
		MaxTransactionWorkUnits allows a complete layout transaction to compare
		many nearby placements without resetting the ordinary engine budget for
		every candidate.

The pages are generated with Golds v0.8.7. (GOOS=linux GOARCH=amd64)
Golds is a Go 101 project developed by Tapir Liu.
PR and bug reports are welcome and can be submitted to the issue list.
Please follow @zigo_101 (reachable from the left QR code) to get the latest news of Golds.