import 'dart:ui' as ui;

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(title: 'ImageFilter on Rect Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: const Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            CustomPaint(
              painter: _MyPainter(),
              size: Size(600, 300),
            ),
          ],
        ),
      ),
    );
  }
}

class _MyPainter extends CustomPainter {
  const _MyPainter();

  ui.Image makeImage() {
    ui.PictureRecorder recorder = ui.PictureRecorder();
    Canvas canvas = Canvas(recorder);
    for (int y = 0; y < 5; y++) {
      for (int x = 0; x < 5; x++) {
        Rect rect = Rect.fromLTWH(x * 20.0, y * 20.0, 20.0, 20.0);
        Color color = ((x + y) & 1) == 0 ? Colors.yellow : Colors.blue;
        print('$color at $rect');
        canvas.drawRect(rect, Paint()..color = color);
      }
    }
    ui.Picture picture = recorder.endRecording();
    return picture.toImageSync(100, 100);
  }

  @override
  void paint(Canvas canvas, Size size) {
    ui.ImageFilter blur = ui.ImageFilter.blur(sigmaX: 5, sigmaY: 5, tileMode: TileMode.decal);
    ui.Shader shader = ui.ImageShader(makeImage(), TileMode.repeated, TileMode.repeated, Matrix4.identity().storage);
    canvas.drawRect(const Rect.fromLTRB(0, 0, 300, 300), Paint()..color = Colors.green);
    canvas.drawRect(const Rect.fromLTRB(100, 100, 200, 200), Paint()..shader = shader);
    canvas.drawRect(const Rect.fromLTRB(300, 0, 600, 300), Paint()..color = Colors.red);
    canvas.drawRect(const Rect.fromLTRB(400, 100, 500, 200), Paint()..shader = shader..imageFilter = blur);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => true;
}