fix: Remove sensorOrientation hack on iOS, it's always portrait

[mrousavy]

What

So either I was completely drunk when building this initially, or I was way too tired already.

But I just re-visited the orientation implementation on iOS, and it seems like .sensorOrientation always returns .portrait!

I just tested this on both my iPhone 15 Pro and my iPhone 8 and they work in every orientation - no matter if landscape or portrait, no matter if front or back camera.

---

I revisited the orientation implementation because I wanted to to get rid of the sensorOrientation hack I built.
The hack was that everytime I want to know the sensorOrientation of an AVCaptureDevice, I have to build up an AVCaptureSession and attach a Video Output to it - which was slow (~5ms per call, 20 calls on an iPhone 15 Pro at startup), and was insanely hacky.
It also crashed when you don't have camera permission yet, or the device is invalid.

This is the hacky code btw:

react-native-vision-camera/package/ios/Core/Extensions/AVCaptureDevice+sensorOrientation.swift

Lines 18 to 73 in 0654898

	var sensorOrientation: Orientation {
	// TODO: There is no iOS API to get native sensor orientation.
	// - The new `RotationCoordinator` API is a blackbox, and cannot be used statically.
	// - Dynamically creating an AVCaptureSession is very hacky and has a runtime overhead.
	// Hopefully iOS adds an API to get sensor orientation soon so we can use that!
	// 0. If we don't have Camera permission yet, we cannot create a temporary AVCaptureSession.
	// So we just return the default orientation as a workaround...
	let cameraPermissionStatus = AVCaptureDevice.authorizationStatus(for: .video)
	if cameraPermissionStatus != .authorized {
	return DEFAULT_SENSOR_ORIENTATION
	}
	// 1. Create a capture session
	let session = AVCaptureSession()
	if session.canSetSessionPreset(.low) {
	session.sessionPreset = .low
	}
	// 2. Add this device as an input
	guard let input = try? AVCaptureDeviceInput(device: self) else {
	VisionLogger.log(level: .error, message: "Cannot dynamically determine \(uniqueID)'s sensorOrientation, " +
	"because the AVCaptureDeviceInput cannot be created. Falling back to \(DEFAULT_SENSOR_ORIENTATION)...")
	return DEFAULT_SENSOR_ORIENTATION
	}
	guard session.canAddInput(input) else {
	VisionLogger.log(level: .error, message: "Cannot dynamically determine \(uniqueID)'s sensorOrientation, because " +
	"it cannot be added to the temporary AVCaptureSession. Falling back to \(DEFAULT_SENSOR_ORIENTATION)...")
	return DEFAULT_SENSOR_ORIENTATION
	}
	session.addInput(input)
	// 3. Add an output (e.g. video data output)
	let output = AVCaptureVideoDataOutput()
	output.automaticallyConfiguresOutputBufferDimensions = false
	output.deliversPreviewSizedOutputBuffers = true
	guard session.canAddOutput(output) else {
	VisionLogger.log(level: .error, message: "Cannot dynamically determine \(uniqueID)'s sensorOrientation, because " +
	"the AVCaptureVideoDataOutput cannot be added to the AVCaptureSession. Falling back to \(DEFAULT_SENSOR_ORIENTATION)...")
	return DEFAULT_SENSOR_ORIENTATION
	}
	session.addOutput(output)
	// 4. Inspect the default orientation of the output
	let defaultOrientation = output.orientation
	// 5. Rotate the default orientation by the default sensor orientation we know of
	var sensorOrientation = defaultOrientation.rotatedBy(orientation: DEFAULT_SENSOR_ORIENTATION)
	// 6. If we are on the front Camera, AVCaptureVideoDataOutput.orientation is mirrored.
	if position == .front {
	sensorOrientation = sensorOrientation.flipped()
	}
	return sensorOrientation
	}

And now I just return .portrait - which works and speeds up the app! :)

Changes

So now sensorOrientation doesn

Tested on

• iPhone 15 Pro
• iPhone 8

Related issues

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