Migrate camera/android from SurfaceTexture->SurfaceProducer. (f…

…lutter#6461)

_**WIP**: We do not plan to land this PR until the next stable release (>= April 3rd 2024)_.

Work towards flutter/flutter#145930.

## Details

Migrates uses of `createSurfaceTexture` to `createSurfaceProducer`, which is intended to have no change in behavior, but _does_ change the backend rendering path, so it will require more testing (and we're also open to minor API renames or changes before it becomes stable).

## Background 

Android plugins previously requested a `SurfaceTexture` from the Android embedder, and used that to produce a `Surface` to render external textures on (i.e. `video_player`).  This worked because 100% of Flutter applications on Android used OpenGLES (via our Skia backend), and `SurfaceTexture` is actually an (opaque) OpenGLES-texture.

Starting soon (roughly ~Q3, this is not a guarantee and just an estimate), Flutter on Android will start to use our new Impeller graphics backend, which on newer devices (`>= API_VERSION_28`), will default to the Vulkan, _not_ OpenGLES. In other words, `SurfaceTexture` will cease to work (it is possible, but non-trivial, to map an OpenGLES texture over to Vulkan).

After consultation with the Android team, they helped us understand that vending `SurfaceTexture` (the _consumer-side_ API) was never the right abstraction, and we should have been vending the _producer-side_ API, or `Surface` directly. The new `SurfaceProducer` API is exactly that - it generates a `Surface`, and similar to our platform view strategy, picks the "right" _consumer-side_ implementation details _for_ the user/plugin packages.

The new `SurfaceProducer` API has 2 possible rendering types (as an implementation detail):

- `SurfaceTexture`, for older OpenGLES devices, which works exactly as it does today.
- `ImageReader`, for newer OpenGLES _or_ Vulkan devices.

These are some subtle nuances in how these two APIs work differently (one example: flutter/flutter#144407), but our theory at this point is we don't expect these changes to be observed by any users, and we have other ideas if necessary. 

> [!NOTE]
> These invariants are [tested on CI in `flutter/engine`](https://github.com/flutter/engine/tree/main/testing/scenario_app/android#ci-configuration).

Points of contact: 
- @matanlurey or @jonahwilliams  (Flutter Engine)
- @johnmccutchan or @reidbaker  (Flutter on Android)

packages/camera/camera_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.10.9+4
+
+* [Supports Impeller](https://docs.flutter.dev/release/breaking-changes/android-surface-plugins).
+
 ## 0.10.9+3
 
 * Updates minimum supported SDK version to Flutter 3.22/Dart 3.4.
@@ -36,7 +40,7 @@
 
 ## 0.10.8+14
 
-* Fixes `pausePreview` null pointer error. `pausePreview` should not be called 
+* Fixes `pausePreview` null pointer error. `pausePreview` should not be called
   when camera is closed or not configured.
 * Updates minimum supported SDK version to Flutter 3.10/Dart 3.0.
 

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/Camera.java

@@ -9,7 +9,6 @@
 import android.app.Activity;
 import android.content.Context;
 import android.graphics.ImageFormat;
-import android.graphics.SurfaceTexture;
 import android.hardware.camera2.CameraAccessException;
 import android.hardware.camera2.CameraCaptureSession;
 import android.hardware.camera2.CameraDevice;
@@ -63,7 +62,7 @@
 import io.flutter.plugins.camera.media.MediaRecorderBuilder;
 import io.flutter.plugins.camera.types.CameraCaptureProperties;
 import io.flutter.plugins.camera.types.CaptureTimeoutsWrapper;
-import io.flutter.view.TextureRegistry.SurfaceTextureEntry;
+import io.flutter.view.TextureRegistry;
 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
@@ -113,7 +112,7 @@ class Camera
    */
   @VisibleForTesting int initialCameraFacing;
 
-  @VisibleForTesting final SurfaceTextureEntry flutterTexture;
+  @VisibleForTesting final TextureRegistry.SurfaceProducer surfaceProducer;
   private final VideoCaptureSettings videoCaptureSettings;
   private final Context applicationContext;
   final DartMessenger dartMessenger;
@@ -214,17 +213,16 @@ public VideoCaptureSettings(@NonNull ResolutionPreset resolutionPreset, boolean
 
   public Camera(
       final Activity activity,
-      final SurfaceTextureEntry flutterTexture,
+      final TextureRegistry.SurfaceProducer surfaceProducer,
       final CameraFeatureFactory cameraFeatureFactory,
       final DartMessenger dartMessenger,
       final CameraProperties cameraProperties,
       final VideoCaptureSettings videoCaptureSettings) {
-
     if (activity == null) {
       throw new IllegalStateException("No activity available!");
     }
     this.activity = activity;
-    this.flutterTexture = flutterTexture;
+    this.surfaceProducer = surfaceProducer;
     this.dartMessenger = dartMessenger;
     this.applicationContext = activity.getApplicationContext();
     this.cameraProperties = cameraProperties;
@@ -243,7 +241,6 @@ public Camera(
     if (videoCaptureSettings.fps != null && videoCaptureSettings.fps.intValue() > 0) {
       recordingFps = videoCaptureSettings.fps;
     } else {
-
       if (SdkCapabilityChecker.supportsEncoderProfiles()) {
         EncoderProfiles encoderProfiles = getRecordingProfile();
         if (encoderProfiles != null && encoderProfiles.getVideoProfiles().size() > 0) {
@@ -256,7 +253,6 @@ public Camera(
     }
 
     if (recordingFps != null && recordingFps.intValue() > 0) {
-
       final FpsRangeFeature fpsRange = new FpsRangeFeature(cameraProperties);
       fpsRange.setValue(new Range<Integer>(recordingFps, recordingFps));
       this.cameraFeatures.setFpsRange(fpsRange);
@@ -307,8 +303,9 @@ private void prepareMediaRecorder(String outputFilePath) throws IOException {
 
     MediaRecorderBuilder mediaRecorderBuilder;
 
-    // TODO(camsim99): Revert changes that allow legacy code to be used when recordingProfile is null
-    // once this has largely been fixed on the Android side. https://github.com/flutter/flutter/issues/119668
+    // TODO(camsim99): Revert changes that allow legacy code to be used when recordingProfile is
+    // null once this has largely been fixed on the Android side.
+    // https://github.com/flutter/flutter/issues/119668
     if (SdkCapabilityChecker.supportsEncoderProfiles() && getRecordingProfile() != null) {
       mediaRecorderBuilder =
           new MediaRecorderBuilder(
@@ -386,7 +383,8 @@ public void onOpened(@NonNull CameraDevice device) {
             cameraDevice = new DefaultCameraDeviceWrapper(device);
             try {
               startPreview();
-              if (!recordingVideo) { // only send initialization if we werent already recording and switching cameras
+              if (!recordingVideo) { // only send initialization if we werent already recording and
+                // switching cameras
                 dartMessenger.sendCameraInitializedEvent(
                     resolutionFeature.getPreviewSize().getWidth(),
                     resolutionFeature.getPreviewSize().getHeight(),
@@ -470,11 +468,10 @@ private void createCaptureSession(
 
     // Build Flutter surface to render to.
     ResolutionFeature resolutionFeature = cameraFeatures.getResolution();
-    SurfaceTexture surfaceTexture = flutterTexture.surfaceTexture();
-    surfaceTexture.setDefaultBufferSize(
+    surfaceProducer.setSize(
         resolutionFeature.getPreviewSize().getWidth(),
         resolutionFeature.getPreviewSize().getHeight());
-    Surface flutterSurface = new Surface(surfaceTexture);
+    Surface flutterSurface = surfaceProducer.getSurface();
     previewRequestBuilder.addTarget(flutterSurface);
 
     List<Surface> remainingSurfaces = Arrays.asList(surfaces);
@@ -1160,7 +1157,8 @@ public void resumePreview() {
   }
 
   public void startPreview() throws CameraAccessException, InterruptedException {
-    // If recording is already in progress, the camera is being flipped, so send it through the VideoRenderer to keep the correct orientation.
+    // If recording is already in progress, the camera is being flipped, so send it through the
+    // VideoRenderer to keep the correct orientation.
     if (recordingVideo) {
       startPreviewWithVideoRendererStream();
     } else {
@@ -1193,7 +1191,6 @@ private void startPreviewWithVideoRendererStream()
     }
 
     if (cameraProperties.getLensFacing() != initialCameraFacing) {
-
       // If the new camera is facing the opposite way than the initial recording,
       // the rotation should be flipped 180 degrees.
       rotation = (rotation + 180) % 360;
@@ -1361,13 +1358,13 @@ public void uncaughtException(Thread thread, Throwable ex) {
 
   public void setDescriptionWhileRecording(
       @NonNull final Result result, CameraProperties properties) {
-
     if (!recordingVideo) {
       result.error("setDescriptionWhileRecordingFailed", "Device was not recording", null);
       return;
     }
 
-    // See VideoRenderer.java; support for this EGL extension is required to switch camera while recording.
+    // See VideoRenderer.java; support for this EGL extension is required to switch camera while
+    // recording.
     if (!SdkCapabilityChecker.supportsEglRecordableAndroid()) {
       result.error(
           "setDescriptionWhileRecordingFailed",
@@ -1400,7 +1397,7 @@ public void dispose() {
     Log.i(TAG, "dispose");
 
     close();
-    flutterTexture.release();
+    surfaceProducer.release();
     getDeviceOrientationManager().stop();
   }
 

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/MethodCallHandlerImpl.java

@@ -393,27 +393,25 @@ private void instantiateCamera(MethodCall call, Result result) throws CameraAcce
     Integer videoBitrate = call.argument("videoBitrate");
     Integer audioBitrate = call.argument("audioBitrate");
 
-    TextureRegistry.SurfaceTextureEntry flutterSurfaceTexture =
-        textureRegistry.createSurfaceTexture();
+    TextureRegistry.SurfaceProducer surfaceProducer = textureRegistry.createSurfaceProducer();
     DartMessenger dartMessenger =
-        new DartMessenger(
-            messenger, flutterSurfaceTexture.id(), new Handler(Looper.getMainLooper()));
+        new DartMessenger(messenger, surfaceProducer.id(), new Handler(Looper.getMainLooper()));
     CameraProperties cameraProperties =
         new CameraPropertiesImpl(cameraName, CameraUtils.getCameraManager(activity));
     ResolutionPreset resolutionPreset = ResolutionPreset.valueOf(preset);
 
     camera =
         new Camera(
             activity,
-            flutterSurfaceTexture,
+            surfaceProducer,
             new CameraFeatureFactoryImpl(),
             dartMessenger,
             cameraProperties,
             new Camera.VideoCaptureSettings(
                 resolutionPreset, enableAudio, fps, videoBitrate, audioBitrate));
 
     Map<String, Object> reply = new HashMap<>();
-    reply.put("cameraId", flutterSurfaceTexture.id());
+    reply.put("cameraId", surfaceProducer.id());
     result.success(reply);
   }