API Reference

Public types grouped by area. Every identifier here exists in the CrimsonCommon runtime module's public headers.

Tag stacks

Type	Description
`FCrimsonTagStack` / `FCrimsonFloatTagStack`	One `(tag, count)` item; `GetTag()`, `GetStackCount()`
`FCrimsonTagStackContainer`	Replicated int container: `AddStack` / `RemoveStack` / `ClearStacks` / `GetStackCount` / `ContainsTag` / `GetStacks`
`FCrimsonFloatTagStackContainer`	Replicated float container; adds `SetStack` to overwrite a value outright
`UCrimsonTagStackStatics`	Blueprint library: `Add/Remove/Clear/Get/Contains TagStack` (+ `Float` variants, `Set Float Tag Stack`)

Ability system bridge

Type	Description
`UCrimsonAbilitySet`	Data asset bundling abilities/effects/attributes; `GiveToAbilitySystem(ASC, &Handles, Source)` (C++) / `K2_GiveToAbilitySystem` -> "Give To Ability System" (BP)
`FCrimsonAbilitySet_GrantedHandles`	Tracks a grant for revocation; `TakeFromAbilitySystem(ASC)`
`UCrimsonAbilitySetStatics`	`RevokeAbilitySet(Handles, ASC)` - BP-friendly revoke (server only)
`ICrimsonAbilitySystemOwner`	Bridge interface: `GrantAbilitySet(Set, Source, &Handles)`, `RemoveGrantedAbilitySet(Handles)` - no ASC getter
`FCrimsonAbilitySet_GameplayAbility` / `_GameplayEffect` / `_AttributeSet`	The asset's entry structs (ability+input tag, effect+level, attribute set+defaults)
`FCrimsonAttributeDefault`	One `(FGameplayAttribute, Value)` base-value override applied at grant time

Interaction contracts

Type	Description
`ICrimsonInteractableTarget`	`GatherInteractionOptions` (C++) / `K2_GatherInteractionOptions` (BP); plus `CustomizeInteractionEventData`, `OnInteractableHovered/Unhovered`, `NotifyInteractionSuccess`
`ICrimsonInteractionInstigator`	`ChooseBestInteractionOption(Query, Options)` - arbitrate when several options are offered
`FCrimsonInteractionOption`	One option: `Text`/`SubText`, `InputType`, `InputHoldDuration`, and ability fields (grant / target ASC / action ability)
`FCrimsonInteractionQuery`	`RequestingAvatar`, `RequestingController`, `OptionalObjectData`
`FCrimsonInteractionOptionBuilder`	Accumulates options and stamps each one's target scope
`ECrimsonInteractionInputType`	`Instant` / `Hold`

Messaging

Type	Description
`UCrimsonMessageSubsystem`	`Get(WorldContext)`; `BroadcastMessage<T>` / `K2_BroadcastMessage` ("Broadcast Message"); `RegisterListener<T>` (lambda / member-fn / params); `UnregisterListener`
`FCrimsonMessageListenerHandle`	Binding handle; `Unregister()`, `IsValid()`
`FCrimsonMessageListenerParams<T>`	Advanced params - `PartialMatch` + pre-bound callback
`ECrimsonMessageMatch`	`ExactMatch` / `PartialMatch`
`UCrimsonAsyncAction_ListenForMessage`	Blueprint async "Listen for Crimson Messages" node

Context menu

Type	Description
`UCrimsonContextAction`	`Blueprintable, EditInlineNew, DefaultToInstanced` base. `BlueprintNativeEvent` hooks: `GetAvailability` (`Hidden`/`Disabled`/`Enabled`; default maps `IsAvailable`), `GetDisabledReason`, `ValidateExecution` (server anti-cheat), `ExecuteAction(Context, Payload)` (server-side), `GetDynamicDisplayName`. Properties: `ActionTag`, `SectionTag`, `SortPriority`, `bIsDefault`, `bIsDestructive`, `ConfirmationMode`, `ConfirmationPrompt`, `CloseBehavior`. `GetActionId()` = wire identity (tag name, else class name)
`UCrimsonContextActionSet`	Reusable `UPrimaryDataAsset` holding an action list (mirrors `UCrimsonAbilitySet`) - the designer-friendly authoring path. `AppendTo(OutActions)` for providers. Same loaded asset on client and server -> deterministic
`UCrimsonContextAction_GrantAbility`	Built-in: `TryActivateAbilityByClass` on the instigator's ASC
`UCrimsonContextAction_DebugMessage`	Test/debug action: logs `Message` at Display verbosity when executed server-side. Drop into any action list to verify the full menu round-trip without gameplay code
`UCrimsonContextAction_FromInteractionOption`	Transient wrapper letting `ICrimsonInteractableTarget`s surface in the menu. Wire id derives from the option ability class; `ValidateExecution` enforces the `crimson.ContextMenu.MaxExecuteDistance` range CVar (default 1000 cm, `<= 0` disables)
`UCrimsonContextActionGatherer`	THE single gather path (provider interface, else interactable actor + components, then registered contributors) + Hidden filtering + deterministic sort (destructive last, section, priority). Helpers: `GatherActions`, `ResolveAction(Actions, ActionId, Occurrence)`, `MakeActionHandle(Actions, Action, OutId, OutOccurrence)`
`ICrimsonContextActionProvider`	`GatherContextActions` - must return a deterministic, identically-ordered list on client and server. Optional native `ValidateContextActionRequest(Context)` rejects wrong-instigator requests server-side (e.g. another player's item)
`ICrimsonContextActionContributor`	Inject actions into OTHER objects' menus (quests add "Turn In" to an NPC). `GatherContextActionsForTarget` inspects `Context.Target` and appends only when relevant. Same determinism contract as providers
`UCrimsonContextActionContributorRegistry`	`UWorldSubsystem`: `RegisterContributor(Object, Priority)` / `UnregisterContributor`. Consulted by the gatherer after the target's own gather, in deterministic (priority, class name) order. Register symmetrically on server and client or contributed actions cannot resolve
`FCrimsonContextActionContext` / `FCrimsonContextActionHandle`	Execution context (instigator/target) / RPC payload (`{ Provider, ActionId, Occurrence, Payload }` - stable id + occurrence-among-same-id, plus an optional `FInstancedStruct` argument)
`UCrimsonContextActionPlayerComponent`	Player-controller component with the `Server_ExecuteContextAction` RPC (not auto-attached). Server flow: re-gather via the gatherer -> `ValidateContextActionRequest` -> resolve by `(ActionId, Occurrence)` -> `GetAvailability == Enabled` -> `ValidateExecution` -> execute. Stale requests drop gracefully

UI foundation

Type	Description
`UCrimsonPrimaryGameLayout`	Layer stack: `GetPrimaryGameLayout(PC/LP)`, `PushWidgetToLayerStack<T>` / `...Async`, `RegisterLayer`, `GetLayerWidget`, `FindAndRemoveWidgetFromLayer`
`UCrimsonGameUIManagerSubsystem` / `UCrimsonGameUIPolicy`	Create and own each local player's root layout; reach it via `GetCurrentUIPolicy()` -> `GetRootLayout` (on the policy); local-multiplayer interaction mode
`UCrimsonUIExtensionSubsystem`	Extension points/widgets: `RegisterExtensionPoint`, `RegisterExtensionAsWidget` (+ `For Context` / `As Data`), `Unregister`, BP `K2_`
`FCrimsonUIExtensionPointHandle` / `FCrimsonUIExtensionHandle`	Handles returned by registration
`UCrimsonUIExtensions`	Statics: `PushContentToLayer_ForPlayer`, `PushStreamedContentToLayer_ForPlayer`, `Suspend/ResumeInputForPlayer`

Modular actors & player layer

Type	Description
`ACrimsonModular*`	`Character`, `Pawn`, `PlayerController`, `PlayerState`, `GameMode[Base]`, `GameState[Base]`, `AIController` - GFP-extensible framework bases
`UCrimsonCommonGameInstance`	Primary-player tracking + `OnPrimaryPlayerSet` hook
`UCrimsonCommonLocalPlayer`	Player-side delegate broadcaster
`ACrimsonCommonPlayerController`	Controller -> local-player bridge
`UCrimsonUserSubsystem`	CommonUser port: login, privileges, online context
`UCrimsonSessionSubsystem`	CommonUser port: host/join/matchmaking, beacons
`ECrimsonUser*` enums + `FCrimsonOnlineResultInformation`	Online context / init state / privilege / availability / async-task state, and a result wrapper (in `CrimsonUserTypes.h`)

Input, teams & utilities

Type	Description
`FCrimsonChordRequirement`	Shift/Ctrl/Alt modifier requirement; `GetDisplayName(BaseKey)`
`ECrimsonGamepadSensitivity`	Ten-point Slow->Insane preset scale
`ICrimsonInputBindingProvider`	Read/write chord requirements per mapping+slot (implemented by CrimsonInput, consumed by CrimsonSettings)
`ICrimsonTeamAgentInterface` / `FOnCrimsonTeamTagsChangedDelegate`	Team/faction membership tags + change delegate; `BroadcastTeamChange` (full system in CrimsonTeams)
`UCrimsonTagLabelSettings`	Project Settings -> Crimson -> Crimson Tag Labels; `GetNameForTag` (C++) / "Get Tag Label" (BP)
`ECrimsonStatDisplayMode` / `ECrimsonDisplayablePerformanceStat`	Perf-stat HUD display mode and the displayable stat set (FPS, frame/latency, packet)
`FCrimsonAsyncMixin`	Sequential async-load mixin (ported from Epic's AsyncMixin)

Logging

Macro	Use
`CRIMSON_DECLARE_LOG_CATEGORY` / `CRIMSON_DEFINE_LOG_CATEGORY`	Declare (header) / define (module .cpp) a named, filterable category
`CRIMSON_LOG_VERBOSE / _INFO / _DISPLAY / _WARN / _ERROR / _FATAL`	Log at a verbosity; `Msg` accepts any value `FString` can build from