I'm trying to save metal textures in a lossless compressed format. I've tried png and tiff, but I run into the same problem: the pixel data changes after save and load when we have transparency. Here is the code I use to save a Tiff: import ImageIO import UIKit import Metal import MobileCoreServices extension MTLTexture { func saveAsLosslessTIFF(url: URL) throws { guard let context = CIContext() else { return } guard let colorSpace = CGColorSpace(name: CGColorSpace.linearSRGB) else { return } guard let ciImage = CIImage(mtlTexture: self, options: [.colorSpace : colorSpace]) else { return } guard let cgImage = context.createCGImage(ciImage, from: ciImage.extent) else { return } // create a dictionary with TIFF compression options let tiffCompression_LZW = 5 let options: [String: Any] = [ kCGImagePropertyTIFFCompression as String: tiffCompression_LZW, kCGImagePropertyDepth as String: depth, kCGImagePropertyPixelWidth as String: width, kCGImagePropertyPixelHeight as String: height, ] let fileDestination = CGImageDestinationCreateWithURL(url as CFURL, kUTTypeTIFF, 1, nil) guard let destination = fileDestination else { throw RuntimeError("Unable to create image destination.") } CGImageDestinationAddImage(destination, cgImage, options as CFDictionary) if !CGImageDestinationFinalize(destination) { throw RuntimeError("Unable to save image to destination.") } } } I can then load the texture like this: func loadTexture(url:URL) throws -> MTLTexture { let usage = MTLTextureUsage(rawValue: MTLTextureUsage.renderTarget.rawValue | MTLTextureUsage.shaderRead.rawValue | MTLTextureUsage.shaderWrite.rawValue) return try loader.newTexture(URL:url,options:[MTKTextureLoader.Option.textureUsage:usage.rawValue,MTKTextureLoader.Option.origin:MTKTextureLoader.Origin.flippedVertically.rawValue]) } After saving and then loading the texture again, I want to get back the exact same texture. And I do, if there is no transparency. Transparent pixels, however, are transformed in a way that I don't understand. Here is an example pixel: [120, 145, 195, 170] -> [144, 174, 234, 170] My first guess would be that something is trying to undo a pre-multiplied alpha that never happened. But the numbers don't seem to work out. For example, if that were the case I'd expect 120 to go to (120 * 255) / 170 = 180 , not 144. Any idea what I am doing wrong?

The wwdc video "Design for spatial input" talks about hands and direct interaction, and uses the example of the keyboard (at around 17:10). The keyboard buttons display a hover state as that gets brighter as the finger gets closer. What do I have to do as a developer to implement this? I understand that hoverEffect and HoverEffectComponent respond to eye contact. Do they also automatically respond to direct touch? Or is there something else that I need to do?

I can't seem to get the rotation gesture to work. Here is my code: struct ContentView: View { @State var rotation:Rotation3D = Rotation3D() var rotate:some Gesture { RotateGesture3D() .targetedToAnyEntity() .onChanged { gesture in rotation = gesture.rotation } } var body: some View { RealityView { content in let box = ModelEntity(mesh: .generateBox(size: 0.25)) box.generateCollisionShapes(recursive: false) box.components.set(InputTargetComponent()) content.add(box) } .gesture(rotate) .rotation3DEffect(rotation) } } I assume it is up to me to apply the rotation with rotation3DEffect but I have also tried it without. Is it just not supported in the simulator? Can I expect it to work on the device? If so, is the code correct?