How do I access the model component of Reality Composer in RealityKit?

Question

I'm trying to change the model component of a text entity created in Reality Composer in my code, but this as! casting the gui-created entity to a reference to an entity with a model component failed.

self.entityReference = scene.realityComposerEntity as! HasModel
textEntity.model!.mesh =  MeshResource.generateText("New Text")

The text entity in RealityKit should have a model property as it has a visual appearance in the ARView, but I don't know how to access it. Does anyone have any idea how?

Are there any other easy ways to dynamically display different text in the same spot using RealityKit/Reality Composer?

Answer 1

To access Reality Composer's ModelComponent in RealityKit try the following approach:

import RealityKit

class ViewController: UIViewController {
    
    @IBOutlet var arView: ARView!
    
    override func viewDidLoad() {
        super.viewDidLoad()            
        arView.environment.background = .color(.darkGray)
        
        let textAnchor = try! SomeText.loadTextScene()     // SomeText is enum          
        let textEntity: Entity = textAnchor.realityComp!.children[0]
        textEntity.scale = [5,5,5]
        
        var textModelComp: ModelComponent = textEntity.children[0].components[ModelComponent]!
                
        var material = SimpleMaterial()
        material.baseColor = .color(.systemTeal)
        textModelComp.materials[0] = material

        textAnchor.realityComp!.children[0].children[0].components.set(textModelComp)
        arView.scene.anchors.append(textAnchor)
    }
}