phase2-unreal/RealityCapture/README.md

# RealityCapture 1.5 → Unreal reality scene

RealityCapture 1.5.1 is installed locally at:

```text
C:\Program Files\Capturing Reality\RealityCapture\RealityCapture.exe
```

The reconstruction pipeline is in `Tools/reconstruct.ps1`. It creates one isolated RealityCapture project and FBX output per repository. The resulting FBX is imported into Unreal as a `UStaticMesh`, then assigned to the `RealityCaptureMesh` property of that repository’s `AGitWorldRepoWorld` actor.

## Input requirement

Provide a deliberate capture folder containing at least three overlapping photos of the same physical scene. The current Downloads folder contains mixed personal/media files, so it is not selected automatically.

## Reconstruct a repository scene

From this `phase2-unreal` directory:

```powershell
& .\RealityCapture\Tools\reconstruct.ps1 `
  -RepositoryId pax-coder `
  -InputFolder 'D:\Captures\pax-coder-plaza'
```

The script runs `-addFolder`, `-align`, `-selectMaximalComponent`, automatic reconstruction-region setup, model calculation, texturing, FBX export, and project save. RealityCapture’s command-line workflow and these reconstruction/export commands are documented by Capturing Reality: [CLI](https://rchelp.capturingreality.com/en-US/tutorials/commandline.htm), [reconstruction examples](https://rchelp.capturingreality.com/en-US/tutorials/commandline_2.htm), and [model export](https://rchelp.capturingreality.com/en-US/tutorials/commandline_3.htm).

## Import into Unreal

1. Generate Visual Studio project files from `GitWorldUnreal.uproject`.
2. Import `RealityCapture/Output/<repository-id>/<repository-id>.fbx` into `/Game/RealityScene/<repository-id>`.
3. Enable Nanite on the imported static mesh and create a collision setup appropriate for walking.
4. Assign the mesh to `RealityCaptureMesh` on the matching `AGitWorldRepoWorld` actor.
5. Adjust `RealitySceneTransform` for centimeters/origin alignment; keep the repo’s walkable bounds around the imported scene.
6. Press Play and walk through the physical scene while build blocks, signs, portals, and events remain attached to the repository sandbox.

The Unreal renderer remains DX12/Nanite/Lumen. CUDA is an optional compute pass for build-field weights; RealityCapture’s photogrammetry reconstruction is run by its own installed application.