--- title: AFS_UX_Overlap product: Advanced Framework Pro version: 1.0 engine: Unreal Engine 5.8 updated: 2026-10-05 canonical: https://docs.human-codeable.com/plugins/afs-ux-overlap.html --- System # AFS_UX_Overlap Overlap-driven interaction for direct touch: buttons and objects pressed with the hand rather than pointed at. #### What it gives you - Direct-touch interaction for VR hands - Identifier filtering so only a fingertip triggers a button - A drag variant for physical sliders and levers #### Requires None #### Required by None 4 assets18 API members ## Description Overlap interaction covers the case where the player touches something rather than pointing at it — the most physically convincing interaction in VR, and the one that needs the most filtering. Without filtering, a whole hand passing near a button triggers it. `BPC_Interaction_Overlap` therefore has **Allowed Identifiers**: only abilities whose identifier appears in the list may trigger it. Setting it to the fingertip ability's identifier makes a button that must be pressed deliberately with a finger. `BPC_Interaction_Overlap_Drag` extends this to drive a `BPC_State_Drag`, which is how physical sliders, dials and drawers are built. ## Setup 1. Enable `AFS_UX_Overlap`. 2. On the target, tag the collision component and add `BPC_Interaction_Overlap`, setting **Component Tag Of Collision** to that tag. 3. Add `BPC_ActorAbility_Overlap` to the hand or fingertip that should be able to press. 4. Bind to **Overlap Started** and **Release**. ## Usage ### Making a fingertip-only button See [Add a pressable button](../workflows/add-pressable-button.html). Set **Allowed Identifiers** to the fingertip ability's identifier. ### Physical sliders Use `BPC_Interaction_Overlap_Drag` with a `BPC_State_Drag` and set **Component Tag Of Drag Comp**. ### Allowing two hands at once Set **Allow Multiple Overlaps** true. [![A fingertip on a button, the button visibly depressed](../images/AFS_UX_Overlap_result-1600.webp?v=436a63dc)](../images/AFS_UX_Overlap_result-1600.webp?v=436a63dc) A fingertip on a button, the button visibly depressed ## Key properties | Property | When to change | |---|---| | `Allowed Identifiers` | Restrict which abilities may trigger; empty accepts any | | `Allow Multiple Overlaps` | Whether several hands may overlap at once | | `Component Tag Of Collision` | Which collision component triggers the interaction | | `Sound Overlap` / `Sound End Overlap` | Touch feedback | ## Extending Derive from `BPC_Interaction_Overlap` for new touch behaviours, or implement `Interface_Overlap` to veto conditionally. ## Example map `Map_Examples_Overlap` shows fingertip buttons and overlap drag. ## Troubleshooting **The button triggers when the hand is near but not touching.** The collision component is larger than the visual, or **Allowed Identifiers** is empty so the whole hand qualifies. **Nothing happens on touch.** The hand has no `BPC_ActorAbility_Overlap`, or the collision channels do not overlap each other. ## API reference Every blueprint asset in this plugin. Expand an asset to see its members. ### Components **BPC_ActorAbility_Overlap**0 members extends `BPC_ActorAbility` Actor ability marking its owner as something overlap interactions react to. It adds no logic beyond the ability base; what matters is the identifier given to it, which overlap interactions match against their allowed list. Add it to a motion controller, a hand or any actor whose collision should be able to trigger an overlap. No editor-visible members; this asset configures defaults only. **BPC_Interaction_Overlap**12 members extends `BPC_Interaction` Interaction that fires when a tagged collision component on the owner is overlapped by an actor carrying the overlap ability. Point Component Tag Of Collision at the primitive that should detect, and list the identifiers you accept; an ability whose identifier is not listed is ignored. The base only reports and plays its sounds, so bind to On Overlap Start or subclass it for a response of your own. | Kind | Name | Signature | Description | |---|---|---|---| | var | `Component Tag Of Collision`Settings | `name` | Tag identifying which collision component on the owner triggers this overlap interaction. | | var | `Allowed Identifiers`Settings | `name[]` | Ability identifiers permitted to overlap this object. Leave empty to accept any. Use it to restrict a button to being pressed by a fingertip rather than a whole hand. | | var | `Allow Multiple Overlaps`Settings | `bool` | Whether several abilities may overlap this object at once, or only the first one to arrive. | | var | `Identifier`Settings | `name` | Name identifying this overlap interaction, reported through Source Info. | | var | `Sound Overlap`Sound | `SoundBase` | Sound played when an ability begins overlapping. | | var | `Sound End Overlap`Sound | `SoundBase` | Sound played when an overlap ends. | | fn | `canBeOverlapped`Overlap | `(OverlapAbility: BPC_ActorAbility_Overlap, out Enabled: bool)` | Returns whether the given overlap ability is currently allowed, consulting Interface Overlap on the owner if implemented. | | fn | `getOverlapComponent`Overlap | `(out OverlapComponent: PrimitiveComponent)` | Returns the collision component matching Component Tag Of Collision. | | event | `OnComponentBeginOverlap_Event_0` | `(OverlappedComponent: PrimitiveComponent, OtherActor: Actor, OtherComp: PrimitiveComponent, OtherBodyIndex: int, bFromSweep: bool, SweepResult: HitResult)` | Internal handler that filters engine overlap events down to allowed abilities. | | event | `OnComponentEndOverlap_Event_0` | `(OverlappedComponent: PrimitiveComponent, OtherActor: Actor, OtherComp: PrimitiveComponent, OtherBodyIndex: int)` | Internal handler that ends the interaction when the overlapping component leaves. | | event | `Release` | `(OverlapAbility: BPC_ActorAbility_Overlap)` | Fires when the overlapping ability leaves. Bind to this to run the release action. | | event | `OverlapStarted` | `(OverlapAbility: BPC_ActorAbility_Overlap, OverlappingComponent: PrimitiveComponent)` | Fires when an allowed ability starts overlapping. Bind to this to run the press or touch action. | **BPC_Interaction_Overlap_Drag**5 members extends `BPC_Interaction_Overlap` Overlap interaction that starts a drag rather than a one-off event. When an overlapping ability arrives it spawns a drag latch at the contact point and hands it to a drag state component on the owner, destroying it again when the overlap ends. Add it to a lever, button or slider whose handle is meant to be pushed by a hand rather than gripped. | Kind | Name | Signature | Description | |---|---|---|---| | var | `Component Tag Of Drag Comp`Drag | `name` | Tag identifying the drag state component this overlap drives, so touching the object moves it along its configured axis. | | fn | `canBeOverlapped`Overlap | `(OverlapAbility: BPC_ActorAbility_Overlap, out Enabled: bool)` | Returns whether the given overlap ability is currently allowed, consulting Interface Overlap on the owner if implemented. | | fn | `getDraggingComp` | `(out DragComp: BPC_State_Drag)` | Returns the drag state component matching the configured tag. | | event | `OverlapStarted` | `(OverlapAbility: BPC_ActorAbility_Overlap, OverlappingComponent: PrimitiveComponent)` | Begins dragging the object when an allowed ability touches it. | | event | `Release` | `(OverlapAbility: BPC_ActorAbility_Overlap)` | Ends the drag when the ability leaves. | ### Interfaces **Interface_Overlap**1 members extends `Interface` Contract for an actor that wants a say in whether it may be overlapped, given the source info and the overlap interaction asking. Nothing in the shipped content calls it, so treat it as an extension point for overlap logic of your own; the shipped overlap interaction decides from its own list of allowed identifiers. | Kind | Name | Signature | Description | |---|---|---|---| | fn | `CanBeOverlapped`Overlap | `(SourceInfo: ST_SourceInfo, CompOverlap: BPC_Interaction_Overlap, out IsOverlappable: bool)` | Implement on an actor to veto or allow overlap interaction under your own conditions. |