Reality Composer Pro 3 Visual Workflow Tools

import SwiftUI
import RealityKit

// MARK: - ContentView
struct AlchemistView: View {
    @State private var isWalking = false
    @State private var rootEntity: Entity?

    var body: some View {
        RealityView { content in
            // Load the scene built in Reality Composer Pro 3
            // The scene contains an entity named "Alchemist" with an
            // AnimationGraphComponent whose graph has an isWalking Bool input.
            if let scene = try? await Entity(named: "AlchemyArea", in: .main) {
                content.add(scene)
                rootEntity = scene
            }
        } update: { content in
            // Propagate the Swift-side toggle into the Animation Graph parameter
            guard let alchemist = rootEntity?.findEntity(named: "Alchemist") else { return }
            setAnimationGraphParameter(
                entity: alchemist,
                key: "isWalking",
                value: isWalking
            )
        }
        .overlay(alignment: .bottom) {
            Button(isWalking ? "Stop Walking" : "Start Walking") {
                isWalking.toggle()
            }
            .buttonStyle(.borderedProminent)
            .padding()
        }
    }

    // MARK: - Animation Graph Parameter Helper
    private func setAnimationGraphParameter(
        entity: Entity,
        key: String,
        value: Bool
    ) {
        // AnimationGraphComponent is the RealityKit runtime component
        // that corresponds to the Animation Graph authored in RCP3.
        guard var graphComponent = entity.components[AnimationGraphComponent.self] else {
            return
        }
        // Set the named Bool parameter; the key must match the
        // parameter name defined in the Animation Graph Inputs Inspector.
        graphComponent.setParameter(key, value: .bool(value))
        entity.components[AnimationGraphComponent.self] = graphComponent
    }
}

// MARK: - Preview
#Preview {
    AlchemistView()
}