ShaderMask is broken and messes up layout, AppBar rendered in the middle of the screen

[sir-boformer]

It seems like there is a bug in the engine in SceneBuilder.pushShaderMask or SceneBuilder.pop that causes this.

This makes ShaderMask unusable.

Example code (taken from the ShaderMask docs):

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Playground',
      home: TestPage(),
    );
  }
}

class TestPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: new AppBar(
        title: Text('Test'),
        backgroundColor: Colors.blue.withOpacity(0.5),
      ),
      body: Center(
        child: ShaderMask(
          shaderCallback: (Rect bounds) {
            return new RadialGradient(
              center: Alignment.topLeft,
              radius: 1.0,
              colors: <Color>[Colors.yellow, Colors.deepOrange.shade900],
              tileMode: TileMode.mirror,
            ).createShader(bounds);
          },
          child: const Text('I’m burning the memories'),
        ),
      ),
    );
  }
}

Flutter version: Latest master

[sir-boformer]

@HansMuller it seems like you initially implemented ShaderMask

[sir-boformer]

Here is what happens when I run the card_collection test in dev/manual_tests with the sunshine option enabled (adds a ShaderMask):

[sir-boformer]

@zoechi Seems like a bug in the engine

[sir-boformer]

Thank you for the fix!

[knopp]

This seems to have caused regression in my case - I had BackdropFilter inside ShaderMask (to apply gradient with darken blend mode over blurred UI). It used to work fine but it does not anymore. Is BackdropFilter inside ShaderMask something that should be working or am I pushing it too far?

[jamesblasco]

@knopp did you find a solution for using BackdropFilter inside ShaderMask ?

[JasCodes]

This is still an issue

[github-actions]

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