render directly to Texture rather than PlatformView (Android only)

lib/filament_controller.dart

@@ -5,7 +5,10 @@ import 'package:flutter/services.dart';
 typedef FilamentAsset = int;
 
 abstract class FilamentController {
-  void onFilamentViewCreated(int id);
+
+  late int textureId;
+  Future initialize(int width, int height);
+  Future resize(int width, int height);
   Future setBackgroundImage(String path);
   Future loadSkybox(String skyboxPath);
   Future removeSkybox();
@@ -45,28 +48,24 @@ abstract class FilamentController {
 }
 
 class PolyvoxFilamentController extends FilamentController {
-  late int _id;
-  late MethodChannel _channel;
 
-  final Function(int id)? onFilamentViewCreatedHandler;
+  late MethodChannel _channel = MethodChannel("app.polyvox.filament/event");
 
-  PolyvoxFilamentController({this.onFilamentViewCreatedHandler});
-
-  @override
-  void onFilamentViewCreated(int id) async {
-    _id = id;
-    _channel = MethodChannel("app.polyvox.filament/filament_view_$id");
+  PolyvoxFilamentController() {
     _channel.setMethodCallHandler((call) async {
       print("Received Filament method channel call : ${call.method}");
-      if (call.method == "ready") {
-        onFilamentViewCreatedHandler?.call(_id);
-        return Future.value(true);
-      } else {
-        throw Exception("Unknown method channel invocation ${call.method}");
-      }
+      throw Exception("Unknown method channel invocation ${call.method}");
     });
   }
 
+  Future initialize(int width, int height) async {
+    textureId = await _channel.invokeMethod("initialize", [width, height]);
+  }
+
+  Future resize(int width, int height) async {
+    await _channel.invokeMethod("resize", [width, height]);
+  }
+
   @override
   Future setBackgroundImage(String path) async {
     await _channel.invokeMethod("setBackgroundImage", path);

lib/filament_widget.dart

@@ -0,0 +1,88 @@
+import 'package:flutter/rendering.dart';
+import 'package:flutter/widgets.dart';
+import 'filament_controller.dart';
+
+
+typedef ResizeCallback = void Function(Size oldSize, Size newSize);
+
+class ResizeObserver extends SingleChildRenderObjectWidget {
+  final ResizeCallback onResized;
+
+  const ResizeObserver({
+    Key? key,
+    required this.onResized,
+    Widget? child,
+  }) : super(
+          key: key,
+          child: child,
+        );
+
+  @override
+  RenderObject createRenderObject(BuildContext context) =>
+      _RenderResizeObserver(onLayoutChangedCallback: onResized);
+}
+
+class _RenderResizeObserver extends RenderProxyBox {
+  final ResizeCallback onLayoutChangedCallback;
+
+  _RenderResizeObserver({
+    RenderBox? child,
+    required this.onLayoutChangedCallback,
+  }) : super(child);
+
+  late var _oldSize = size;
+
+  @override
+  void performLayout() {
+    super.performLayout();
+    if (size != _oldSize) {
+      onLayoutChangedCallback(_oldSize, size);
+      _oldSize = size;
+    }
+  }
+}
+
+class FilamentWidget extends StatefulWidget {
+
+  final FilamentController controller;
+
+  const FilamentWidget({Key? key, required this.controller}) : super(key: key);
+
+  @override
+  _FilamentWidgetState createState() => _FilamentWidgetState();
+}
+
+class _FilamentWidgetState extends State<FilamentWidget> {
+
+  bool _ready = false;
+
+  @override
+  void initState() {
+    WidgetsBinding.instance.addPostFrameCallback((timeStamp) async {
+      var size = ((context.findRenderObject()) as RenderBox).size;
+      print("Requesting texture creation for Filament of size $size");
+      await widget.controller.initialize(size.width.toInt(), size.height.toInt());
+      print("Filament texture available");
+      setState(() {
+        _ready = true;
+      });
+    });
+    
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if(!_ready) {
+      return Container();
+    }
+    return ResizeObserver(
+      onResized: (Size oldSize, Size newSize) async {
+        await widget.controller.resize(newSize.width.toInt(), newSize.height.toInt());
+      },
+      child:Texture(
+      textureId: widget.controller.textureId,
+      filterQuality: FilterQuality.none,
+    ));
+  }
+}

lib/gesture_detecting_filament_view.dart

@@ -2,7 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 
 import 'filament_controller.dart';
-import 'view/filament_widget.dart';
+import 'filament_widget.dart';
 
 class GestureDetectingFilamentView extends StatefulWidget {
   final FilamentController controller;

lib/view/filament_view.dart

@@ -1,39 +0,0 @@
-import 'package:flutter/foundation.dart';
-import 'package:flutter/gestures.dart';
-import 'package:flutter/rendering.dart';
-import 'package:flutter/widgets.dart';
-
-import 'filament_view_platform.dart';
-
-class FilamentView extends FilamentViewPlatform {
-  static const FILAMENT_VIEW_ID = 'app.polyvox.filament/filament_view';
-
-  @override
-  Widget buildView(
-    int creationId,
-    FilamentViewCreatedCallback onFilamentViewCreated,
-  ) {
-    switch (defaultTargetPlatform) {
-      case TargetPlatform.android:
-        return AndroidView(
-            viewType: FILAMENT_VIEW_ID,
-            gestureRecognizers: <Factory<OneSequenceGestureRecognizer>>{},
-            hitTestBehavior: PlatformViewHitTestBehavior.opaque,
-            onPlatformViewCreated: (id) {
-              onFilamentViewCreated(id);
-            });
-      case TargetPlatform.iOS:
-        return UiKitView(
-          viewType: FILAMENT_VIEW_ID,
-          onPlatformViewCreated: (int id) {
-            onFilamentViewCreated(id);
-          },
-        );
-      case TargetPlatform.windows:
-        return Text("Flutter doesn't support platform view on Windows yet.");
-      default:
-        return Text(
-            '$defaultTargetPlatform is not yet implemented by Filament plugin.');
-    }
-  }
-}

lib/view/filament_view_platform.dart

@@ -1,21 +0,0 @@
-import 'package:flutter/widgets.dart';
-import 'package:polyvox_filament/view/filament_view.dart';
-import 'package:plugin_platform_interface/plugin_platform_interface.dart';
-
-typedef FilamentViewCreatedCallback = void Function(int id);
-
-abstract class FilamentViewPlatform extends PlatformInterface {
-  FilamentViewPlatform() : super(token: _token);
-
-  static final Object _token = Object();
-  static final FilamentViewPlatform _instance = FilamentView();
-
-  static FilamentViewPlatform get instance => _instance;
-
-  Widget buildView(
-    int creationId,
-    FilamentViewCreatedCallback onFilamentViewCreated,
-  ) {
-    throw UnimplementedError('buildView() has not been implemented.');
-  }
-}

lib/view/filament_widget.dart

@@ -1,29 +0,0 @@
-import 'package:flutter/foundation.dart';
-import 'package:flutter/gestures.dart';
-import 'package:flutter/rendering.dart';
-import 'package:flutter/widgets.dart';
-import 'package:polyvox_filament/view/filament_view.dart';
-
-import '../filament_controller.dart';
-import 'filament_view_platform.dart';
-
-int _nextFilamentCreationId = 0;
-
-class FilamentWidget extends StatefulWidget {
-  final FilamentController controller;
-
-  const FilamentWidget({Key? key, required this.controller}) : super(key: key);
-
-  @override
-  _FilamentWidgetState createState() => _FilamentWidgetState();
-}
-
-class _FilamentWidgetState extends State<FilamentWidget> {
-  final _viewId = _nextFilamentCreationId++;
-
-  @override
-  Widget build(BuildContext context) {
-    return FilamentViewPlatform.instance
-        .buildView(_viewId, widget.controller.onFilamentViewCreated);
-  }
-}