SoundTrace SDK for Unreal Engine

The UE5 SDK connects STCoreV2 through Unreal Audio Extension plugins and Actor Components. The current source project targets Unreal Engine 5.6 and includes selection paths for native Unreal Audio, FMOD, and Wwise integrations.

Current status

Area	Status
Engine	Unreal Engine 5.6
Plugin	Plugins/SoundTracing
Declared targets	Win64, macOS, Linux, Android, iOS
Prebuilt binary in this checkout	Win64 Release
Demo scenes	Three documentation placeholders; scene assets are not included yet

Other target platforms require the corresponding STCoreV2 binary in the distributed package.

Installation

1. Close the project.
2. Copy Plugins/SoundTracing into the target project's Plugins/ directory.
3. Open the .uproject and enable the SoundTracing plugin.
4. Restart the editor and complete module compilation.
5. Open Project Settings > Plugins > SoundTracing.

YourProject/
└─ Plugins/
   └─ SoundTracing/
      ├─ Content/
      ├─ Source/
      └─ ThirdParty/

Unreal Audio settings

For each target platform, select:

Spatialization Plugin: SoundTracing
Source Data Override Plugin: SoundTracing

The sample project uses 48 kHz, a 1024-frame callback, and one queued buffer. Verify functionality with the current project audio budget before tuning it.

Fastest setup

1. Project settings

Initially decide only:

• HRTF: Band8 or Parametric
• Whether to request GPU propagation
• Default path enable states

Keep ray resolution, depth, and early-path budgets at their defaults.

2. Source settings assets

Create reusable SoundTracing Audio Spatialization Settings assets in the Content Browser. Treat shared assets as presets instead of editing every Audio Component independently.

Preset asset	Use
ST_Source_Fast	Many simultaneous or background sources
ST_Source_Middle	Normal gameplay sources
ST_Source_Quality	Hero sources and quality-first demos

The current plugin exposes advanced source properties, but most projects should change only intensity, path enable flags, and attenuation overrides.

3. Audio Component

Assign the shared SoundTracing settings asset to the Audio Component or Sound Attenuation spatialization plugin settings.

4. Geometry

Add SoundTracingObjectComponent as a direct child of the target StaticMeshComponent or SkinnedMeshComponent. The current implementation uses its immediate parent mesh.

5. Materials

Run Sync Materials From Parent to map render-material names to SoundTrace material presets, then correct only mismatched slots.

HRTF

The primary guide uses two modes.

Mode	Behavior
Band8	Lightweight rendering without an external HRTF asset
Parametric	Measured rendering using a KU100 parametric table

The source also contains Convolution and SteamAudio advanced modes. Use them only in distributions that have validated the corresponding assets and platform binaries.

GPU backend

Enabling bEnableGpuPropagation requests GPU-provider initialization.

• Successful initialization uses GPU propagation.
• Missing exports, devices, or backends continue on CPU.
• Win64 packages must stage webgpu_dawn.dll.
• GPU deployments should use a compatible LBVH-family geometry setup.

Confirm the actual path through the Output Log message: SoundTracing GPU propagation enabled or the CPU fallback warning.

Material presets

The plugin content includes a default SoundTraceMaterialPresetLibrary. SoundTracingObjectComponent maps render-material names and aliases to presets. Start with the bundled presets; raw 8-band reflection, absorption, transmission, and scattering edits belong in a separate custom library.

Object updates

Mode	Use
Static	Non-moving level geometry
Dynamic	Transform-only doors and props
Refit	Skinned meshes with changing vertex pose
Rebuild	Geometry whose topology changes

Path visualization

Add SoundTracingPathVisualizerComponent to display Niagara-based path segments. It is a debugging/demo feature and should be disabled during shipping performance measurements.

Demo scene placeholders

The current checkout does not contain these three demo assets. These sections reserve the documentation pattern that will be connected when the scenes ship.

SampleScene01 — Basic Room

:::note Placeholder Basic source, listener, static room geometry, material presets, and direct/reflection paths. :::

SampleScene02 — Material and Dynamic Door

:::note Placeholder Shared source presets, material changes, dynamic-door occlusion, and CPU/GPU comparison. :::

SampleScene03 — Multiroom

:::note Placeholder Multiple sources, room transitions, diffraction/transmission, and HRTF direction. :::

Troubleshooting

Symptom	Check
Plugin is missing from the selector	Plugin enable state, module compile, and platform Audio settings
Native library load failure	Target-specific binaries and staged dependencies under ThirdParty/STCoreV2
Source is not spatialized	SoundTracing source settings asset assigned to the Audio Component
Geometry is ignored	Object Component's immediate parent is a supported mesh component
GPU falls back to CPU	GPU provider/export/device and webgpu_dawn.dll staging
Paths are not visible	Visualizer component, Niagara plugin, and path enable states

Next

• Unity SDK
• Web SDK
• STCoreV2