hollow-spray-0532

readme.md

hollow-spray-0532

Created with <3 with dartpad.dev.

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: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Text(
      'Hello, World!',
      style: Theme.of(context).textTheme.headlineMedium,
    );
  }
}



class FanWidget extends StatefulWidget {
  /// Fan color
  final Color color;

  /// Background color
  final Color? backgroundColor;

  /// Size (Diameter)
  final double size;

  /// Rotation period
  final Duration period;

  /// Whether to animate the fan
  final bool powerOn;

  const FanWidget({
    super.key,
    required this.color,
    this.backgroundColor,
    this.size = 54,
    this.period = const Duration(seconds: 1),
    required this.powerOn,
  });

  @override
  State<FanWidget> createState() => _FanWidgetState();
}

class _FanWidgetState extends State<FanWidget>
    with SingleTickerProviderStateMixin {
  double speed = 0;
  static const m = 1; //kg

  double _lastTime = DateTime.now().millisecond.toDouble();

  double f = 0;
  double s = 0;
  double p = 0;

  late final ctrl = AnimationController.unbounded(vsync: this);

  static const _period = 0.150;

  late final timer =
      Timer.periodic(Duration(milliseconds: 150), (t) => physics(t));

  void physics(Timer timer) {
    // DT in seconds
    final dt = _period; //max(t - _lastTime, 1) * 1e-3;

    double motor = 0;

    if (widget.powerOn) {
      final motorPower = 1.0;
      //period.inMilliseconds * 1e-3;
      motor = 1 * motorPower;
    } else {
      // break
      f *= 0.5;
    }
    final airResistance = 0;
    //-s * dt;
    f += motor + airResistance;

    final a = f / m;
    s += .5 * a * dt;
    p += s * dt;

    ctrl.value = p / 10;

    // if (s <= 0)
    //   powerOn = false;
    // else
    //   period = Duration(milliseconds: (1000 / p).round());

    debugPrint(
        "physics: dt:${dt.toStringAsFixed(1)} |f: ${f.toStringAsFixed(1)} | a:${a.toStringAsFixed(1)}|s: ${s.toStringAsFixed(1)}|p: ${p.toStringAsFixed(1)}"); //|period:${period.inMilliseconds}|powerOn: $powerOn");
  }

  @override
  void initState() {
    _lastTime = DateTime.now().millisecond.toDouble();
    // ctrl.value = 200;
    // ctrl.animateWith(
    //   FrictionSimulation(
    //       0.55, // <- the bigger this value, the less friction is applied
    //       ctrl.value,
    //       100 /*period.inMilliseconds */ // <- Velocity of inertia
    //       ),
    // );
    //f = m * a;
    super.initState();
  }

  @override
  void dispose() {
    timer.cancel();
    ctrl.dispose();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    //final t = DateTime.now().millisecond.toDouble();

    final color = widget.color;
    final size = widget.size;
    var powerOn = widget.powerOn;
    var period = widget.period;

    final fan =Container(width:30, height:30), color: Colors.red);

    return//period.inMilliseconds > 1
          powerOn
              ? RotatingWidget(period: period, child: fan)
              //Transform.rotate(angle: ctrl.value, child: fan)
              : fan,
    );
  }
}