API reference — Unreal SDK

The public, game-dev-facing API of the AR51SDK Unreal plugin (Runtime module), described from the caller's side — what you place, configure, call, and receive in C++ or Blueprint.

Looking for a specific type?

The Class index lists every public type with its own reference page. The sections below are topic groupings.

• Plugin: AR51SDK · version 2.3.2.4 (AR51SDK.uplugin).
• Modules: AR51SDK (Runtime; Win64/Android) + AR51SDKEditor (editor tooling — not covered here). Plugin deps: ProceduralMeshComponent, AnimationWarping.
• Public include root: Plugins/AR51SDK/Source/AR51SDK/Public/ (export macro AR51SDK_API).

Units & space — read this first

Unreal world units are centimeters and rotations are degrees. AR 51 mocap/CVS data is natively meters (and a different coordinate convention). Conversion happens at the SDK boundary; use UAnchorServiceComponent::AR51SDKToWorldSpace / WorldToAR51SDKSpace whenever you exchange positions/rotations with the AR 51 system. Values whose unit/space wasn't explicit in source are flagged ⚠️ inline.

Blueprint vs C++

Each member notes its exposure. BlueprintCallable / BlueprintPure / BlueprintAssignable are reachable from Blueprint; C++ only members are not (UFUNCTION absent in source). Items marked ⚠️ unverified are inferred from source and should be confirmed before you rely on them.

Sections

Section	Covers
Connection & services	AAR51SDK root actor, EPlatformTypes, the service components, AR 51 ↔ world-space conversion
Skeletons & characters	USkeletonConsumer, UAR51Character, AAR51CharacterActor, mapping assets, SkeletonData / Keypoints / IPersonBase, person events, prediction & solver settings
Object detection	UObjectDetectionConsumer, UTrackedInstance, FMarkerItem, EInstanceType
Hands, boundary & anchors	HandJointInfo, hand/boundary adapter interfaces + factories, anchor components
Utilities & platform	EPlatformTypes, UNetworkUtils, the AR51SDK log category, UnrealThread, ISingleton

Platform plugins & LiveLink — separate

The VR/MR platform plugins (AR51SDK_QUEST, AR51SDK_WAVE, AR51SDK_OPENXR, AR51SDK_PICO), AR51SDK_LIVELINK, and AR51_RenderStream (Disguise) ship as separate plugins and are not part of this AR51SDK Runtime-module reference. Their dedicated reference is pending.

New to the SDK? Start with the connect → drive a character walkthrough at the bottom of Skeletons & characters.