camera fixes for assets with large bounding boxes

lib/filament_controller.dart

@@ -197,7 +197,7 @@ abstract class FilamentController {
   ///
   /// Called by `FilamentGestureDetector`. You probably don't want to call this yourself.
   ///
-  Future zoomUpdate(double z);
+  Future zoomUpdate(double x, double y, double z);
 
   ///
   /// Called by `FilamentGestureDetector`. You probably don't want to call this yourself.

lib/filament_controller_ffi.dart

@@ -191,16 +191,45 @@ class FilamentControllerFFI extends FilamentController {
     _isReadyForScene.complete(true);
   }
 
+  ///
+  /// I'm not exactly sure how to resize the backing textures on all platforms.
+  /// So for now, I'm sticking with the safe option when the widget is resized: destroying the swapchain, recreating the textures, and creating a new swapchain.
+  ///
   @override
   Future resize(int width, int height, {double scaleFactor = 1.0}) async {
     _resizing = true;
     setRendering(false);
+    _lib.destroy_swap_chain(_viewer!);
+    await destroyTexture();
     size = ui.Size(width * _pixelRatio, height * _pixelRatio);
-    _textureId = await _channel
-        .invokeMethod("resize", [size.width, size.height, scaleFactor]);
-    _textureIdController.add(_textureId);
+
+    var textures =
+        await _channel.invokeMethod("createTexture", [size.width, size.height]);
+    var flutterTextureId = textures[0];
+    _textureId = flutterTextureId;
+
+    // void* on iOS (pointer to pixel buffer), void* on Android (pointer to native window), null on Windows/macOS
+    var surfaceAddress = textures[1] as int? ?? 0;
+
+    // null on iOS/Android, void* on MacOS (pointer to metal texture), GLuid on Windows/Linux
+    var nativeTexture = textures[2] as int? ?? 0;
+
+    _lib.create_swap_chain_ffi(
+        _viewer!,
+        Pointer<Void>.fromAddress(surfaceAddress),
+        size.width.toInt(),
+        size.height.toInt());
+    if (nativeTexture != 0) {
+      assert(surfaceAddress == 0);
+      print("Creating render target from native texture  $nativeTexture");
+      _lib.create_render_target_ffi(
+          _viewer!, nativeTexture, size.width.toInt(), size.height.toInt());
+    }
+
     _lib.update_viewport_and_camera_projection_ffi(
-        _viewer!, size.width.toInt(), size.height.toInt(), scaleFactor);
+        _viewer!, size.width.toInt(), size.height.toInt(), 1.0);
+
+    _textureIdController.add(_textureId);
     _resizing = false;
     setRendering(true);
   }
@@ -553,11 +582,11 @@ class FilamentControllerFFI extends FilamentController {
   }
 
   @override
-  Future zoomUpdate(double z) async {
+  Future zoomUpdate(double x, double y, double z) async {
     if (_viewer == null || _resizing) {
       throw Exception("No viewer available, ignoring");
     }
-    _lib.scroll_update(_viewer!, 0.0, 0.0, z);
+    _lib.scroll_update(_viewer!, x, y, z);
   }
 
   @override

lib/filament_controller_method_channel.dart

@@ -434,11 +434,11 @@ class FilamentControllerMethodChannel extends FilamentController {
     await _channel.invokeMethod("scrollBegin");
   }
 
-  Future zoomUpdate(double z) async {
+  Future zoomUpdate(double x, double y, double z) async {
     if (_viewer == null || _resizing) {
       throw Exception("No viewer available, ignoring");
     }
-    await _channel.invokeMethod("scrollUpdate", [0.0, 0.0, z]);
+    await _channel.invokeMethod("scrollUpdate", [x, y, z]);
   }
 
   Future zoomEnd() async {

lib/widgets/filament_gesture_detector.dart

@@ -38,15 +38,12 @@ class FilamentGestureDetector extends StatelessWidget {
   ///
   final bool listenerEnabled;
 
-  final double zoomDelta;
-
   const FilamentGestureDetector(
       {Key? key,
       required this.controller,
       this.child,
       this.showControlOverlay = false,
-      this.listenerEnabled = true,
-      this.zoomDelta = 1})
+      this.listenerEnabled = true})
       : super(key: key);
 
   @override

lib/widgets/filament_gesture_detector_desktop.dart

@@ -32,15 +32,12 @@ class FilamentGestureDetectorDesktop extends StatefulWidget {
   ///
   final bool listenerEnabled;
 
-  final double zoomDelta;
-
   const FilamentGestureDetectorDesktop(
       {Key? key,
       required this.controller,
       this.child,
       this.showControlOverlay = false,
-      this.listenerEnabled = true,
-      this.zoomDelta = 1})
+      this.listenerEnabled = true})
       : super(key: key);
 
   @override
@@ -71,15 +68,18 @@ class _FilamentGestureDetectorDesktopState
   ///
   /// Scroll-wheel on desktop, interpreted as zoom
   ///
-  void _zoom(PointerScrollEvent pointerSignal) {
+  void _zoom(PointerScrollEvent pointerSignal) async {
     _scrollTimer?.cancel();
-    widget.controller.zoomBegin();
-    widget.controller.zoomUpdate(pointerSignal.scrollDelta.dy > 0
-        ? widget.zoomDelta
-        : -widget.zoomDelta);
-    _scrollTimer = Timer(const Duration(milliseconds: 100), () {
-      widget.controller.zoomEnd();
-      _scrollTimer = null;
+    await widget.controller.zoomBegin();
+    await widget.controller.zoomUpdate(
+        pointerSignal.localPosition.dx,
+        pointerSignal.localPosition.dy,
+        pointerSignal.scrollDelta.dy > 0 ? 1 : -1);
+
+    // we don't want to end the zoom in the same frame, because this will destroy the camera manipulator (and cancel the zoom update).
+    // here, we just defer calling [zoomEnd] for 100ms to ensure the update is propagated through.
+    _scrollTimer = Timer(Duration(milliseconds: 100), () async {
+      await widget.controller.zoomEnd();
     });
   }
 
@@ -108,7 +108,8 @@ class _FilamentGestureDetectorDesktopState
           // if this is the first move event, we need to call rotateStart/panStart to set the first coordinates
           if (!_pointerMoving) {
             if (d.buttons == kTertiaryButton) {
-              widget.controller.rotateStart(d.position.dx, d.position.dy);
+              widget.controller
+                  .rotateStart(d.localPosition.dx, d.localPosition.dy);
             } else {
               widget.controller
                   .panStart(d.localPosition.dx, d.localPosition.dy);
@@ -117,7 +118,8 @@ class _FilamentGestureDetectorDesktopState
           // set the _pointerMoving flag so we don't call rotateStart/panStart on future move events
           _pointerMoving = true;
           if (d.buttons == kTertiaryButton) {
-            widget.controller.rotateUpdate(d.position.dx, d.position.dy);
+            widget.controller
+                .rotateUpdate(d.localPosition.dx, d.localPosition.dy);
           } else {
             widget.controller.panUpdate(d.localPosition.dx, d.localPosition.dy);
           }

lib/widgets/filament_gesture_detector_mobile.dart

@@ -158,8 +158,8 @@ class _FilamentGestureDetectorMobileState
               },
               onScaleUpdate: (ScaleUpdateDetails d) async {
                 if (d.pointerCount == 2) {
-                  widget.controller
-                      .zoomUpdate(d.horizontalScale > 1 ? 0.1 : -0.1);
+                  widget.controller.zoomUpdate(d.localFocalPoint.dx,
+                      d.localFocalPoint.dy, d.horizontalScale > 1 ? 0.1 : -0.1);
                 } else if (!_scaling) {
                   if (_rotateOnPointerMove) {
                     widget.controller