graphx_particle.dart

import 'dart:async';
import 'dart:ui' as ui;

import 'package:flutter/material.dart';
import 'package:graphx/graphx.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const Home(),
    );
  }
}

class Home extends StatelessWidget {
  const Home({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: SceneBuilderWidget(
          builder: () => SceneController(
            back: SimpleShapes(),
          ),
          child: const SizedBox.expand(),
        ),
      ),
    );
  }
}

Future<ui.Image> getImage(String path) async {
  final byteData = await rootBundle.load(path);
  return await decodeImageFromList(byteData.buffer.asUint8List());
}

class SimpleShapes extends GSprite {
  final particle = GSimpleParticle();

  @override
  void addedToStage() {
    super.addedToStage();

    getImage('assets/small.png').then((image) {
      final texture = GTexture.fromImage(image);
      final emitter = GSimpleParticleSystem()
        ..x = 400
        ..y = 200
        ..initialColor = 0xff00ff
        ..initialScale = 0.4
        ..endAlpha = 0.2
        ..initialScale = 1.0
        ..endScale = 0.1
        ..emissionDelay = 0.0
        ..initialAcceleration = 0.12
        ..dispersionXVariance = 240
        ..dispersionYVariance = 240
        ..dispersionAngle = 2.0
        ..dispersionAngleVariance = 80
        ..emit = true
        ..energy = 12.0
        ..texture = texture;

      emitter.setup(40);
      addChild(emitter..init());
    });
  }
}