title: makeRenderPipelineState failed [output of type ushort is not compatible with a MTLPixelFormatR16Float color attachement.]
body: <p>I'm trying to present some text using realitykit, the code compiles, the scene starts but however no text is shown in the scene.</p>
  
  <p>I'm using an iPhone 7 running iOS 13.1.2, i tried the same code but with a box Mesh Resource and it works just fine. </p>
  
  <p>My controller looks like this</p>
  
  <pre><code>    func makeUIView(context: Context) -&gt; ARView {
  
          let arView = ARView(frame: .zero)
  
          let anchor = AnchorEntity(plane: .horizontal)
  
          let mesh = MeshResource.generateText("text")
          let color = UIColor.systemBlue
          let material = UnlitMaterial(color: color)
          let entity = ModelEntity(mesh: mesh, materials: [material])
  
          anchor.addChild(entity)
  
          // Add the box anchor to the scene
          arView.scene.anchors.append(anchor)
  
          return arView
  
      }
  </code></pre>
  
  <p>As i said before when i get to runtime the console show these errors:</p>
  
  <pre><code>2019-10-02 09:07:33.707275+0200 tesss[646:78901] Compiler failed to build request
  2019-10-02 09:07:33.707476+0200 tesss[646:78901] [Graphics] makeRenderPipelineState failed [output of type ushort is not compatible with a MTLPixelFormatR16Float color attachement.].
  2019-10-02 09:07:33.707507+0200 tesss[646:78901] [Graphics] makeRenderPipelineState failed.
  </code></pre>