Custom clipping stuff

main.dart

import 'package:flutter/material.dart';

const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: ClipPath(
            clipper: ShapeClipper(),
            child: Container(
              height: 450,
              width: 400,
              color: Colors.blueAccent,
            ),
          ),
        ),
      ),
    );
  }
}

class ShapeClipper extends CustomClipper<Path> {
  @override
  Path getClip(Size size) {
    Path path = Path()
      ..moveTo(0,0)
      ..lineTo(0, size.height)
      ..lineTo((size.width / 4) * 1, size.height - 50)
      ..lineTo((size.width / 4) * 2, size.height)
      ..lineTo((size.width / 4) * 3, size.height - 50)
      ..lineTo(size.width, size.height)
      ..lineTo(size.width, 0)
      ..close();

    return path;
  }

  @override
  bool shouldReclip(covariant CustomClipper<Path> oldClipper) {
    return true;
  }
}