fix: Fix focus() on iOS (#1943)

This commit is contained in:
Marc Rousavy 2023-10-06 14:30:12 +02:00 committed by GitHub
parent 9d71990570
commit a4448c3a7d
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2 changed files with 62 additions and 58 deletions

View File

@ -9,55 +9,8 @@
import Foundation
extension CameraView {
private func rotateFrameSize(frameSize: CGSize, orientation: UIInterfaceOrientation) -> CGSize {
switch orientation {
case .portrait, .portraitUpsideDown, .unknown:
// swap width and height since the input orientation is rotated
return CGSize(width: frameSize.height, height: frameSize.width)
case .landscapeLeft, .landscapeRight:
// is same as camera sensor orientation
return frameSize
@unknown default:
return frameSize
}
}
/// Converts a Point in the UI View Layer to a Point in the Camera Frame coordinate system
private func convertLayerPointToFramePoint(layerPoint point: CGPoint) -> CGPoint {
guard let videoDeviceInput = videoDeviceInput else {
invokeOnError(.session(.cameraNotReady))
return .zero
}
guard let viewScale = window?.screen.scale else {
invokeOnError(.unknown(message: "View has no parent Window!"))
return .zero
}
let frameSize = rotateFrameSize(frameSize: videoDeviceInput.device.activeFormat.videoDimensions,
orientation: outputOrientation)
let viewSize = CGSize(width: previewView.bounds.width * viewScale,
height: previewView.bounds.height * viewScale)
let scale = min(frameSize.width / viewSize.width, frameSize.height / viewSize.height)
let scaledViewSize = CGSize(width: viewSize.width * scale, height: viewSize.height * scale)
let overlapX = scaledViewSize.width - frameSize.width
let overlapY = scaledViewSize.height - frameSize.height
let scaledPoint = CGPoint(x: point.x * scale, y: point.y * scale)
return CGPoint(x: scaledPoint.x - (overlapX / 2), y: scaledPoint.y - (overlapY / 2))
}
/// Converts a Point in the UI View Layer to a Point in the Camera Device Sensor coordinate system (x: [0..1], y: [0..1])
private func captureDevicePointConverted(fromLayerPoint pointInLayer: CGPoint) -> CGPoint {
guard let videoDeviceInput = videoDeviceInput else {
invokeOnError(.session(.cameraNotReady))
return .zero
}
let frameSize = rotateFrameSize(frameSize: videoDeviceInput.device.activeFormat.videoDimensions,
orientation: outputOrientation)
let pointInFrame = convertLayerPointToFramePoint(layerPoint: pointInLayer)
return CGPoint(x: pointInFrame.x / frameSize.width, y: pointInFrame.y / frameSize.height)
private func convertPreviewCoordinatesToCameraCoordinates(_ point: CGPoint) -> CGPoint {
return previewView.captureDevicePointConverted(fromLayerPoint: point)
}
func focus(point: CGPoint, promise: Promise) {
@ -70,24 +23,71 @@ extension CameraView {
}
// in {0..1} system
let normalizedPoint = captureDevicePointConverted(fromLayerPoint: point)
let normalizedPoint = convertPreviewCoordinatesToCameraCoordinates(point)
do {
try device.lockForConfiguration()
device.focusPointOfInterest = normalizedPoint
device.focusMode = .continuousAutoFocus
if device.isExposurePointOfInterestSupported {
device.exposurePointOfInterest = normalizedPoint
device.exposureMode = .continuousAutoExposure
defer {
device.unlockForConfiguration()
}
device.unlockForConfiguration()
// Set Focus
if device.isFocusPointOfInterestSupported {
device.focusPointOfInterest = normalizedPoint
device.focusMode = .autoFocus
}
// Set Exposure
if device.isExposurePointOfInterestSupported {
device.exposurePointOfInterest = normalizedPoint
device.exposureMode = .autoExpose
}
// Remove any existing listeners
NotificationCenter.default.removeObserver(self,
name: NSNotification.Name.AVCaptureDeviceSubjectAreaDidChange,
object: nil)
// Listen for focus completion
device.isSubjectAreaChangeMonitoringEnabled = true
NotificationCenter.default.addObserver(self,
selector: #selector(subjectAreaDidChange),
name: NSNotification.Name.AVCaptureDeviceSubjectAreaDidChange,
object: nil)
return nil
} catch {
throw CameraError.device(DeviceError.configureError)
}
}
}
@objc
func subjectAreaDidChange(notification _: NSNotification) {
guard let device = videoDeviceInput?.device else {
invokeOnError(.session(.cameraNotReady))
return
}
do {
try device.lockForConfiguration()
defer {
device.unlockForConfiguration()
}
// Reset Focus to continuous/auto
if device.isFocusPointOfInterestSupported {
device.focusMode = .continuousAutoFocus
}
// Reset Exposure to continuous/auto
if device.isExposurePointOfInterestSupported {
device.exposureMode = .continuousAutoExposure
}
// Disable listeners
device.isSubjectAreaChangeMonitoringEnabled = false
} catch {
invokeOnError(.device(.configureError))
}
}
}

View File

@ -42,6 +42,10 @@ class PreviewView: UIView {
return videoPreviewLayer.layerRectConverted(fromMetadataOutputRect: rect)
}
func captureDevicePointConverted(fromLayerPoint point: CGPoint) -> CGPoint {
return videoPreviewLayer.captureDevicePointConverted(fromLayerPoint: point)
}
init(frame: CGRect, session: AVCaptureSession) {
super.init(frame: frame)
videoPreviewLayer.session = session