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AFS_Core_Highlight

Hover feedback in three interchangeable styles — material parameter, mesh copy and shared post-process outline — spawned on demand by interactions.

What it gives you

Three highlight styles with different cost and appearance
Automatic lifetime: no unhover event to handle
Shared stencil pooling for the post-process style

Requires

AFM_MeshCopy

Required by

AFM_Abilities AFS_UX_Grip AF_Examples

6 assets24 API members

Description

Highlighting is deliberately not built into interactions. An interaction names a Highlight Class and the framework spawns it on first hover — so an object that is never hovered never pays for the component.

The three styles trade cost against flexibility. The material style writes parameters on the object's own material and is cheapest. The mesh-copy style duplicates the geometry under a highlight material, for objects whose materials you do not control. The post-process style assigns a custom depth stencil and draws a true outline through a shared full-screen pass, pooling stencil indices by colour.

Lifetime is handled by a timeout rather than by explicit events: TickHighlight is called each frame while hovering, and the highlight ends automatically once the calls stop.

Setup

Enable AFS_Core_Highlight.
On any interaction component, set Highlight Class and Highlight Color.
For the post-process style, confirm Custom Depth-Stencil is enabled in Project Settings.

Warning

The Engine.ini that enables custom depth ships in AFS_Core_Snapping, not in this plugin. If you are using highlighting without snapping, set Custom Depth-Stencil Pass to Enabled with Stencil under Project Settings, Rendering yourself — otherwise the post-process style silently draws nothing. The other two styles are unaffected.

Usage

Choosing a style

Style Use when

BPC_Highlight_Material You control the object's material. Cheapest.

BPC_Highlight_MeshCopy You cannot modify the material.

BPC_Highlight_PostProcess You want a true outline and can afford the pass.

Style	Use when
`BPC_Highlight_Material`	You control the object's material. Cheapest.
`BPC_Highlight_MeshCopy`	You cannot modify the material.
`BPC_Highlight_PostProcess`	You want a true outline and can afford the pass.

Limiting which meshes highlight

Tag the meshes and set Highlight Tag on the interaction. Leave it empty to highlight everything.

Changing colour at runtime

Call UpdateHighlightColor on the interaction component.

Key properties

Property When to change

Highlight Color Per interaction, to signal type or state

Highlight Tag To restrict which meshes respond

Parameter Color / Parameter Highlight On the material style, to match your material's parameter names

Sound Start / Sound Stop Hover feedback

Property	When to change
`Highlight Color`	Per interaction, to signal type or state
`Highlight Tag`	To restrict which meshes respond
`Parameter Color` / `Parameter Highlight`	On the material style, to match your material's parameter names
`Sound Start` / `Sound Stop`	Hover feedback

Extending

See Custom highlight style. Derive from BPC_Highlight and override StartHighlight, EndHighlight and UpdateColor.

Performance notes

Performance

On mobile and standalone headsets prefer the material style. The post-process style costs a full-screen pass and requires Custom Depth-Stencil.

Example map

Map_Examples_Highlight shows all three styles side by side on identical objects.

Troubleshooting

Post-process highlights do not draw. Custom Depth-Stencil is disabled in Project Settings → Rendering.

The material style does nothing. The object's material does not expose the parameter names set in Parameter Color and Parameter Highlight.

API reference

Every blueprint asset in this plugin. Expand an asset to see its members.

Components

BPC_Highlight9 members

extends ActorComponent

Kind	Name	Signature	Description
var	`HighlightColor`Color	`LinearColor`	Colour used to highlight the object. Normally supplied by the interaction component that spawns this highlight.
var	`Sound_Start`Sound	`SoundBase`	Sound played when highlighting begins.
var	`Sound_Stop`Sound	`SoundBase`	Sound played when highlighting ends.
var	`HighlightTag`References	`name`	Component tag limiting which meshes on the owner are highlighted. Leave empty to highlight every mesh.
fn	`getComponentsToHighlight`	`(out MeshComponents: MeshComponent[])`	Returns the mesh components this highlight applies to, honouring the Highlight Tag filter.
fn	`StartHighlight`	`()`	Begins the highlight effect and plays the start sound. Override in a subclass to implement a new highlight style.
fn	`EndHighlight`	`()`	Ends the highlight effect and plays the stop sound. Override in a subclass to implement a new highlight style.
event	`TickHighlight`	`()`	Keeps the highlight alive for this frame. The highlight ends automatically once these calls stop arriving, so hovering needs no explicit end event.
event	`UpdateColor`	`(HighlightColor: LinearColor)`	Changes the highlight colour while the highlight is running.

BPC_Highlight_Material6 members

extends BPC_Highlight

Kind	Name	Signature	Description
var	`Parameter_Color`Settings	`name`	Name of the colour parameter on the object's material that this highlight writes to.
var	`Parameter_Highlight`Settings	`name`	Name of the scalar parameter on the object's material that this highlight toggles.
event	`StartHighlight`	`()`	Enables the highlight by driving the configured material parameters.
event	`EndHighlight`	`()`	Disables the highlight by resetting the configured material parameters.
event	`SetHighlight`	`(Set: bool)`	Sets the highlight parameter directly, bypassing the start and stop transitions.
event	`UpdateColor`	`(HighlightColor: LinearColor)`	Writes a new colour into the material's colour parameter.

BPC_Highlight_MeshCopy2 members

extends BPC_Highlight

Kind	Name	Signature	Description
event	`StartHighlight`	`()`	Spawns a copy of the object's meshes rendered with the highlight material. Use this style when the object's own material cannot be modified.
event	`EndHighlight`	`()`	Overrides the base end-of-highlight step with an empty body, because this variant's mesh copy removes itself as it fades out. Nothing needs doing here unless a child adds state of its own.

BPC_Highlight_PostProcess3 members

extends BPC_Highlight

Kind	Name	Signature	Description
fn	`getPostProcess`	`(out PostProcess: BP_PostProcess_Highlight)`	Returns the shared post-process highlight actor, creating it if this is the first highlight in the level.
event	`StartHighlight`	`()`	Assigns a custom depth stencil to the object so the shared post-process pass draws an outline around it.
event	`EndHighlight`	`()`	Releases the object's stencil so the outline is removed.

Helper

BP_Helper_MeshCopy_Highlight0 members

extends BP_Helper_MeshCopy

No editor-visible members; this asset configures defaults only.

PostProcess

BP_PostProcess_Highlight4 members

extends Actor

Kind	Name	Signature	Description
fn	`RequestStencilForColor`	`(RequestColor: LinearColor, Reference: Object, out Stencil: int)`	Reserves a custom depth stencil index for the requested outline colour and returns it. Colours are pooled, so objects sharing a colour share a stencil.
fn	`ReleaseStencil`	`(Reference: Object)`	Releases the stencil previously reserved for the given object.
fn	`FreeUpUnusedStencil`	`()`	Reclaims stencil indices no longer referenced by any object, keeping the limited stencil range available.
fn	`getOutlineMaterial`	`(out OutlineMaterial: MaterialInstanceDynamic)`	Returns the dynamic material instance driving the outline post-process, so colours can be updated at runtime.