[camera_android_camerax] Remove logic used to previously correct preview rotation (#8256)

camsim99 · web-flow · commit aad08ecb973e · 2025-01-09T19:30:52.000Z
Removes correction logic used to the correct the rotation of the camera preview, since it appears* to not be needed anymore. Partially addresses flutter/flutter#154241. *This is **not true** for emulators, but if we are ok landing this issue for real devices, I'll file an issue for emulators and follow up there. jonahwilliams@ mentioned there is known different behavior in emulators with Impeller, so this fact is not totally a surprise. My basis for landing this is: 1. I tested the following devices that use both Impeller backends and this PR works: - Realme X2 Pro, Android 11 (API 30) that uses Vulkan - Pixel 3A, Android 12 (Android 31/32) that falls back to OpenGLES - Samsung Galaxy (Android 8.1.0) that uses OpenGLES 2. If this misses an edge case (like a class of device), this PR will make it easier to debug what is going on, since the camera preview will now **only** introduce a rotation if the device itself is rotated (as per the logic in https://github.com/flutter/packages/blob/8ca81bd20231ed638cfc3ebf5f8a3f96b3d22e60/packages/camera/camera/lib/src/camera_preview.dart#L46-L72) with no additional logic concerning the sensor orientation and UI orientation as it does now.
diff --git a/packages/camera/camera_android_camerax/CHANGELOG.md b/packages/camera/camera_android_camerax/CHANGELOG.md
@@ -1,7 +1,8 @@
-## NEXT
+## 0.6.12
 
 * Suppresses deprecation and removal warnings for
   `TextureRegistry.SurfaceProducer.onSurfaceDestroyed`.
+* Removes logic added to correct the rotation of the camera preview, since it is no longer required.
 
 ## 0.6.11
 
diff --git a/packages/camera/camera_android_camerax/lib/src/android_camera_camerax.dart b/packages/camera/camera_android_camerax/lib/src/android_camera_camerax.dart
@@ -10,7 +10,7 @@ import 'package:camera_platform_interface/camera_platform_interface.dart';
 import 'package:flutter/services.dart'
     show DeviceOrientation, PlatformException;
 import 'package:flutter/widgets.dart'
-    show RotatedBox, Size, Texture, Widget, visibleForTesting;
+    show Size, Texture, Widget, visibleForTesting;
 import 'package:stream_transform/stream_transform.dart';
 
 import 'analyzer.dart';
@@ -237,26 +237,10 @@ class AndroidCameraCameraX extends CameraPlatform {
   @visibleForTesting
   late bool cameraIsFrontFacing;
 
-  /// Whether or not the Surface used to create the camera preview is backed
-  /// by a SurfaceTexture.
-  @visibleForTesting
-  late bool isPreviewPreTransformed;
-
-  /// The initial orientation of the device.
-  ///
-  /// The camera preview will use this orientation as the natural orientation
-  /// to correct its rotation with respect to, if necessary.
-  @visibleForTesting
-  DeviceOrientation? naturalOrientation;
-
   /// The camera sensor orientation.
   @visibleForTesting
   late int sensorOrientation;
 
-  /// The current orientation of the device.
-  @visibleForTesting
-  DeviceOrientation? currentDeviceOrientation;
-
   /// Subscription for listening to changes in device orientation.
   StreamSubscription<DeviceOrientationChangedEvent>?
       _subscriptionForDeviceOrientationChanges;
@@ -399,20 +383,7 @@ class AndroidCameraCameraX extends CameraPlatform {
 
     final Camera2CameraInfo camera2CameraInfo =
         await proxy.getCamera2CameraInfo(cameraInfo!);
-    await Future.wait(<Future<Object>>[
-      SystemServices.isPreviewPreTransformed()
-          .then((bool value) => isPreviewPreTransformed = value),
-      proxy
-          .getSensorOrientation(camera2CameraInfo)
-          .then((int value) => sensorOrientation = value),
-      proxy
-          .getUiOrientation()
-          .then((DeviceOrientation value) => naturalOrientation ??= value),
-    ]);
-    _subscriptionForDeviceOrientationChanges = onDeviceOrientationChanged()
-        .listen((DeviceOrientationChangedEvent event) {
-      currentDeviceOrientation = event.orientation;
-    });
+    sensorOrientation = await proxy.getSensorOrientation(camera2CameraInfo);
 
     return flutterSurfaceTextureId;
   }
@@ -865,68 +836,7 @@ class AndroidCameraCameraX extends CameraPlatform {
       );
     }
 
-    final Widget cameraPreview = Texture(textureId: cameraId);
-    final Map<DeviceOrientation, int> degreesForDeviceOrientation =
-        <DeviceOrientation, int>{
-      DeviceOrientation.portraitUp: 0,
-      DeviceOrientation.landscapeRight: 90,
-      DeviceOrientation.portraitDown: 180,
-      DeviceOrientation.landscapeLeft: 270,
-    };
-    int naturalDeviceOrientationDegrees =
-        degreesForDeviceOrientation[naturalOrientation]!;
-
-    if (isPreviewPreTransformed) {
-      // If the camera preview is backed by a SurfaceTexture, the transformation
-      // needed to correctly rotate the preview has already been applied.
-      // However, we may need to correct the camera preview rotation if the
-      // device is naturally landscape-oriented.
-      if (naturalOrientation == DeviceOrientation.landscapeLeft ||
-          naturalOrientation == DeviceOrientation.landscapeRight) {
-        final int quarterTurnsToCorrectForLandscape =
-            (-naturalDeviceOrientationDegrees + 360) ~/ 4;
-        return RotatedBox(
-            quarterTurns: quarterTurnsToCorrectForLandscape,
-            child: cameraPreview);
-      }
-      return cameraPreview;
-    }
-
-    // Fix for the rotation of the camera preview not backed by a SurfaceTexture
-    // with respect to the naturalOrientation of the device:
-
-    final int signForCameraDirection = cameraIsFrontFacing ? 1 : -1;
-
-    if (signForCameraDirection == 1 &&
-        (currentDeviceOrientation == DeviceOrientation.landscapeLeft ||
-            currentDeviceOrientation == DeviceOrientation.landscapeRight)) {
-      // For front-facing cameras, the image buffer is rotated counterclockwise,
-      // so we determine the rotation needed to correct the camera preview with
-      // respect to the naturalOrientation of the device based on the inverse of
-      // naturalOrientation.
-      naturalDeviceOrientationDegrees += 180;
-    }
-
-    // See https://developer.android.com/media/camera/camera2/camera-preview#orientation_calculation
-    // for more context on this formula.
-    final double rotation = (sensorOrientation +
-            naturalDeviceOrientationDegrees * signForCameraDirection +
-            360) %
-        360;
-    int quarterTurnsToCorrectPreview = rotation ~/ 90;
-
-    if (naturalOrientation == DeviceOrientation.landscapeLeft ||
-        naturalOrientation == DeviceOrientation.landscapeRight) {
-      // We may need to correct the camera preview rotation if the device is
-      // naturally landscape-oriented.
-      quarterTurnsToCorrectPreview +=
-          (-naturalDeviceOrientationDegrees + 360) ~/ 4;
-      return RotatedBox(
-          quarterTurns: quarterTurnsToCorrectPreview, child: cameraPreview);
-    }
-
-    return RotatedBox(
-        quarterTurns: quarterTurnsToCorrectPreview, child: cameraPreview);
+    return Texture(textureId: cameraId);
   }
 
   /// Captures an image and returns the file where it was saved.
diff --git a/packages/camera/camera_android_camerax/pubspec.yaml b/packages/camera/camera_android_camerax/pubspec.yaml
@@ -2,7 +2,7 @@ name: camera_android_camerax
 description: Android implementation of the camera plugin using the CameraX library.
 repository: https://github.com/flutter/packages/tree/main/packages/camera/camera_android_camerax
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
-version: 0.6.11
+version: 0.6.12
 
 environment:
   sdk: ^3.6.0
diff --git a/packages/camera/camera_android_camerax/test/android_camera_camerax_test.dart b/packages/camera/camera_android_camerax/test/android_camera_camerax_test.dart
@@ -50,8 +50,7 @@ import 'package:camera_android_camerax/src/zoom_state.dart';
 import 'package:camera_platform_interface/camera_platform_interface.dart';
 import 'package:flutter/services.dart'
     show DeviceOrientation, PlatformException, Uint8List;
-import 'package:flutter/widgets.dart'
-    show BuildContext, RotatedBox, Size, Texture, Widget;
+import 'package:flutter/widgets.dart' show BuildContext, Size, Texture, Widget;
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mockito/annotations.dart';
 import 'package:mockito/mockito.dart';
@@ -920,9 +919,7 @@ void main() {
     expect(camera.recorder!.qualitySelector, isNull);
   });
 
-  test(
-      'createCamera sets sensor and device orientations needed to correct preview rotation as expected',
-      () async {
+  test('createCamera sets sensor orientation as expected', () async {
     final AndroidCameraCameraX camera = AndroidCameraCameraX();
     const CameraLensDirection testLensDirection = CameraLensDirection.back;
     const int testSensorOrientation = 270;
@@ -933,8 +930,6 @@ void main() {
     const bool enableAudio = true;
     const ResolutionPreset testResolutionPreset = ResolutionPreset.veryHigh;
     const DeviceOrientation testUiOrientation = DeviceOrientation.portraitDown;
-    const DeviceOrientation testCurrentOrientation =
-        DeviceOrientation.portraitUp;
 
     // Mock/Detached objects for (typically attached) objects created by
     // createCamera.
@@ -965,18 +960,7 @@ void main() {
     await camera.createCamera(testCameraDescription, testResolutionPreset,
         enableAudio: enableAudio);
 
-    const DeviceOrientationChangedEvent testEvent =
-        DeviceOrientationChangedEvent(testCurrentOrientation);
-
-    DeviceOrientationManager.deviceOrientationChangedStreamController
-        .add(testEvent);
-
-    // Wait for currentDeviceOrientation to update.
-    await Future<void>.value();
-
-    expect(camera.naturalOrientation, testUiOrientation);
     expect(camera.sensorOrientation, testSensorOrientation);
-    expect(camera.currentDeviceOrientation, testCurrentOrientation);
   });
 
   test(
@@ -1336,148 +1320,12 @@ void main() {
     // bound to the lifecycle of the camera.
     camera.previewInitiallyBound = true;
 
-    // Tell camera the Surface used to build camera preview is backed by a
-    // SurfaceTexture.
-    camera.isPreviewPreTransformed = true;
-
-    camera.naturalOrientation = DeviceOrientation.portraitDown;
-
     final Widget widget = camera.buildPreview(cameraId);
 
     expect(widget is Texture, isTrue);
     expect((widget as Texture).textureId, cameraId);
   });
 
-  test(
-      'buildPreview returns preview with expected rotation if camera is not front facing and the preview is not backed by a SurfaceTexture',
-      () async {
-    final AndroidCameraCameraX camera = AndroidCameraCameraX();
-    const int cameraId = 33;
-
-    // Tell camera that createCamera has been called and thus, preview has been
-    // bound to the lifecycle of the camera.
-    camera.previewInitiallyBound = true;
-
-    // Tell camera the Surface used to build camera preview is not backed by a
-    // SurfaceTexture.
-    camera.isPreviewPreTransformed = false;
-
-    // Mock sensor and device orientation.
-    camera.sensorOrientation = 270;
-    camera.cameraIsFrontFacing = false;
-    camera.naturalOrientation = DeviceOrientation.portraitUp;
-
-    final double expectedRotation = (camera.sensorOrientation +
-            0 /* the natural orientation in clockwise degrees */ *
-                -1 /* camera is not front facing */ +
-            360) %
-        360;
-    final int expectedQuarterTurns = (expectedRotation / 90).toInt();
-
-    final Widget widget = camera.buildPreview(cameraId);
-
-    expect(widget is RotatedBox, isTrue);
-    expect((widget as RotatedBox).quarterTurns, expectedQuarterTurns);
-    expect(widget.child is Texture, isTrue);
-    expect((widget.child! as Texture).textureId, cameraId);
-  });
-
-  test(
-      'buildPreview returns preview with expected rotation if camera is front facing, the current orientation is landscape, and the preview is not backed by a SurfaceTexture',
-      () async {
-    final AndroidCameraCameraX camera = AndroidCameraCameraX();
-    const int cameraId = 7;
-
-    // Tell camera that createCamera has been called and thus, preview has been
-    // bound to the lifecycle of the camera.
-    camera.previewInitiallyBound = true;
-
-    // Tell camera the Surface used to build camera preview is not backed by a
-    // SurfaceTexture.
-    camera.isPreviewPreTransformed = false;
-
-    // Mock sensor and device orientation.
-    camera.sensorOrientation = 270;
-    camera.naturalOrientation = DeviceOrientation.portraitUp;
-    camera.cameraIsFrontFacing = true;
-
-    // Calculate expected rotation with offset due to counter-clockwise rotation
-    // of the image with th efront camera in use.
-    final double expectedRotation = ((camera.sensorOrientation +
-                0 /* the natural orientation in clockwise degrees */ *
-                    1 /* camera is front facing */ +
-                360) %
-            360) +
-        180;
-    final int expectedQuarterTurns = (expectedRotation / 90).toInt() % 4;
-
-    // Test landscape left.
-    camera.currentDeviceOrientation = DeviceOrientation.landscapeLeft;
-    Widget widget = camera.buildPreview(cameraId);
-
-    expect(widget is RotatedBox, isTrue);
-    expect((widget as RotatedBox).quarterTurns, expectedQuarterTurns);
-    expect(widget.child is Texture, isTrue);
-    expect((widget.child! as Texture).textureId, cameraId);
-
-    // Test landscape right.
-    camera.currentDeviceOrientation = DeviceOrientation.landscapeRight;
-    widget = camera.buildPreview(cameraId);
-
-    expect(widget is RotatedBox, isTrue);
-    expect((widget as RotatedBox).quarterTurns, expectedQuarterTurns);
-    expect(widget.child is Texture, isTrue);
-    expect((widget.child! as Texture).textureId, cameraId);
-  });
-
-  test(
-      'buildPreview returns preview with expected rotation if camera is front facing, the current orientation is not landscape, and the preview is not backed by a SurfaceTexture',
-      () async {
-    final AndroidCameraCameraX camera = AndroidCameraCameraX();
-    const int cameraId = 733;
-
-    // Tell camera that createCamera has been called and thus, preview has been
-    // bound to the lifecycle of the camera.
-    camera.previewInitiallyBound = true;
-
-    // Tell camera the Surface used to build camera preview is not backed by a
-    // SurfaceTexture.
-    camera.isPreviewPreTransformed = false;
-
-    // Mock sensor and device orientation.
-    camera.sensorOrientation = 270;
-    camera.naturalOrientation = DeviceOrientation.portraitUp;
-    camera.cameraIsFrontFacing = true;
-
-    // Calculate expected rotation without offset needed for landscape orientations
-    // due to counter-clockwise rotation of the image with th efront camera in use.
-    final double expectedRotation = (camera.sensorOrientation +
-            0 /* the natural orientation in clockwise degrees */ *
-                1 /* camera is front facing */ +
-            360) %
-        360;
-
-    final int expectedQuarterTurns = (expectedRotation / 90).toInt() % 4;
-
-    // Test portrait up.
-    camera.currentDeviceOrientation = DeviceOrientation.portraitUp;
-    Widget widget = camera.buildPreview(cameraId);
-
-    expect(widget is RotatedBox, isTrue);
-    expect((widget as RotatedBox).quarterTurns, expectedQuarterTurns);
-    expect(widget.child is Texture, isTrue);
-    expect((widget.child! as Texture).textureId, cameraId);
-
-    // Test portrait down.
-    camera.currentDeviceOrientation = DeviceOrientation.portraitDown;
-    widget = camera.buildPreview(cameraId);
-
-    expect(widget is RotatedBox, isTrue);
-    expect((widget as RotatedBox).quarterTurns, expectedQuarterTurns);
-    expect(widget.child is Texture, isTrue);
-    expect((widget.child! as Texture).textureId, cameraId);
-  });
-
   group('video recording', () {
     test(
         'startVideoCapturing binds video capture use case, updates saved camera instance and its properties, and starts the recording',
