Hardware Video & Rendering Pipeline

This page explains how Quest 3D WebView achieves smooth 1080p60 web video on 3D meshes without the black screens or performance bottlenecks common in standard VR web plugins.

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The Core Technical Innovation

In Unreal Engine mobile Vulkan, standard UMG WebBrowser plugins attempt to paint the DOM into an off-screen CPU software canvas before uploading pixels to a GPU texture.

This fails on hardware-accelerated video (such as YouTube, Twitch, Netflix, or Vimeo) because modern Android video decoders write directly into private hardware GPU overlay surfaces (SurfaceView) that software canvases cannot read.

The VirtualDisplay Solution

Quest 3D WebView creates an isolated Android VirtualDisplay backed by a hardware ImageReader:

┌─────────────────────────┐
│ Android System WebView  │
└───────────┬─────────────┘
            │ (Paints DOM & Video at 60 FPS)
            ▼
┌─────────────────────────┐
│ Hardware VirtualDisplay │
└───────────┬─────────────┘
            │ (Acquires Hardware Surface Frames)
            ▼
┌─────────────────────────┐
│ Hardware ImageReader    │
└───────────┬─────────────┘
            │ (Atomic Double-Buffered Bitmap Lock via NDK)
            ▼
┌─────────────────────────┐
│ AndroidBitmap_lockPixels│
└───────────┬─────────────┘
            │ (Direct memcpy to RHI Texture on Render Thread)
            ▼
┌─────────────────────────┐
│ Unreal Dynamic Texture  │──► Dynamic Material Instance on 3D Mesh
└─────────────────────────┘

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Key Benefits of This Architecture

1. Zero Video Black Screens:
   • HTML5 <video> tags and WebGL canvases are rendered natively by the Snapdragon GPU and VPU.
2. Double-Buffered Atomic Swapping:
   • Front and back buffers are swapped with atomic pointer operations, completely eliminating horizontal screen tearing during rapid 60 FPS video playback.
3. Dirty-Frame Gating:
   • If the webpage is idle (e.g. reading an article, viewing a static dashboard), the pipeline executes zero pixel copies and zero GPU texture updates, saving precious mobile battery life and thermals.

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Configuring Resolution & Materials

Resolution Settings

You can customize the virtual display resolution in the Details Panel of QuestWebViewComponent:

• Width: 1920 (Default) | 1280 (720p Mode) | 2560 (1440p Mode) | 3840 (4K Mode)
• Height: 1080 (Default) | 720 (720p Mode) | 1440 (1440p Mode) | 2160 (4K Mode)

Automatic Material Binding

If you assign a base material asset to the MaterialAsset property in the Details Panel, QuestWebViewComponent automatically:

1. Instantiates a UMaterialInstanceDynamic at runtime.
2. Applies the live UTexture2DDynamic to the parameter specified by TextureMaterialParameterName (default: "WebViewTexture").
3. Assigns the material instance to the owning Actor's UMeshComponent automatically!