Reality Composer Pro 3

import SwiftUI
import RealityKit

// MARK: - visionOS app entry point demonstrating loading an RCP3 scene bundle
// The .realitycomposerpro package produced by Reality Composer Pro 3 contains
// baked lightmap textures and prototype instances automatically resolved at load.

struct AlchemyAreaView: View {
    @State private var rootEntity: Entity? = nil
    @State private var loadError: String? = nil

    var body: some View {
        RealityView { content in
            do {
                // Load the named scene from the Reality Composer Pro bundle.
                // The bundle includes baked Lightmap textures generated by
                // the new Lightmaps component in Reality Composer Pro 3.
                let scene = try await Entity(
                    named: "AlchemyArea",
                    in: Bundle.main
                )
                content.add(scene)
                rootEntity = scene
            } catch {
                loadError = error.localizedDescription
            }
        } update: { content in
            // Entity graph, prototype instances, and lightmap textures
            // are all resolved automatically by RealityKit at load time.
            guard let root = rootEntity else { return }
            _ = root // scene is live in content
        }
        .overlay(alignment: .bottom) {
            if let errorMessage = loadError {
                Text("Failed to load scene: \(errorMessage)")
                    .foregroundStyle(.red)
                    .padding()
                    .background(.ultraThinMaterial, in: RoundedRectangle(cornerRadius: 12))
                    .padding()
            }
        }
    }
}

// MARK: - App entry
@main
struct AlchemyApp: App {
    var body: some Scene {
        WindowGroup {
            AlchemyAreaView()
        }
        .windowStyle(.volumetric)
    }
}