books

packages/idraw/lib/p18/p18.dart

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+export 'p18_page.dart';

packages/idraw/lib/p18/p18_page.dart

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+import 'package:flutter/material.dart';
+
+import 'package:components/components.dart';
+import 's01.dart' as s1;
+import 's02.dart' as s2;
+import 's03.dart' as s3;
+import 's04.dart' as s4;
+import 's05.dart' as s5;
+
+class P18Page extends StatelessWidget {
+  const P18Page({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return const DemoShower(
+      srcCodeDir: 'draw/p18',
+
+      demos:  [
+        s1.Paper(),
+        s2.Paper(),
+        s3.Paper(),
+        s4.Paper(),
+        // s5.Paper(),
+      ],
+    );
+  }
+}

packages/idraw/lib/p18/s01.dart

@@ -0,0 +1,201 @@
+import 'dart:math';
+
+// import 'dart:ui' as ui;
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020/11/5
+/// contact me by email 1981462002@qq.com
+/// 说明:
+
+class Paper extends StatelessWidget {
+  const Paper({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      alignment: Alignment.center,
+      child: const World(),
+    );
+  }
+}
+
+class World extends StatefulWidget {
+  const World({super.key});
+
+  @override
+  _WorldState createState() => _WorldState();
+}
+
+class _WorldState extends State<World> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  ParticleManage pm = ParticleManage();
+
+  @override
+  void initState() {
+    super.initState();
+    initParticleManage();
+
+    _controller = AnimationController(
+      duration: const Duration(seconds: 1),
+      vsync: this,
+    )
+      ..addListener(pm.tick)
+    // ..repeat()
+        ;
+  }
+
+  void initParticleManage() {
+    pm.size = Size(300, 200);
+    Particle particle = Particle(x: 0, y: 0, vx: 3, vy: 0,ay: 0.05,
+        color: Colors.blue, size: 8);
+    pm.particles = [particle];
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  theWorld(){
+    if (_controller.isAnimating) {
+      _controller.stop();
+    } else {
+      _controller.repeat();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: theWorld,
+      child: CustomPaint(
+        size: pm.size,
+        painter: WorldRender(manage: pm),
+      ),
+    );
+  }
+}
+
+class ParticleManage with ChangeNotifier {
+  List<Particle> particles = [];
+
+  Size size;
+
+  ParticleManage({this.size = Size.zero});
+
+  void setParticles(List<Particle> particles) {
+    this.particles = particles;
+  }
+
+  void addParticle(Particle particle) {
+    particles.add(particle);
+    notifyListeners();
+  }
+
+  void tick() {
+    particles.forEach(doUpdate);
+    notifyListeners();
+  }
+
+  void doUpdate(Particle p) {
+    p.vy += p.ay; // y加速度变化
+    p.vx += p.ax; // x加速度变化
+    p.x += p.vx;
+    p.y += p.vy;
+    if (p.x > size.width) {
+      p.x = size.width;
+      p.vx = -p.vx;
+    }
+    if (p.x < 0) {
+      p.x = 0;
+      p.vx = -p.vx;
+    }
+    if (p.y > size.height) {
+      p.y = size.height;
+      p.vy = -p.vy;
+    }
+    if (p.y < 0) {
+      p.y = 0;
+      p.vy = -p.vy;
+    }
+  }
+
+  void reset() {
+    particles.forEach((p) {
+      p.x = 0;
+    });
+    notifyListeners();
+  }
+}
+
+class WorldRender extends CustomPainter {
+
+  final ParticleManage manage;
+
+  Paint fillPaint = Paint();
+
+  Paint stokePaint = Paint()
+    ..strokeWidth = 0.5
+    ..style = PaintingStyle.stroke;
+
+  WorldRender({required this.manage}) : super(repaint: manage);
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    canvas.drawRect(Offset.zero & size, stokePaint);
+    manage.particles.forEach((particle) {
+      drawParticle(canvas, particle);
+    });
+  }
+
+  void drawParticle(Canvas canvas, Particle particle) {
+    fillPaint.color = particle.color;
+    canvas.drawCircle(Offset(particle.x, particle.y), particle.size, fillPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant WorldRender oldDelegate) =>
+      oldDelegate.manage != manage;
+}
+
+
+class Particle {
+  /// x 位移.
+  double x;
+
+  /// y 位移.
+  double y;
+
+  /// 粒子水平速度.
+  double vx;
+
+  // 粒子水平加速度
+  double ax;
+
+  // 粒子竖直加速度
+  double ay;
+
+  ///粒子竖直速度.
+  double vy;
+
+
+  /// 粒子大小.
+  double size;
+
+  /// 粒子颜色.
+  Color color;
+
+  Particle({
+    this.x = 0,
+    this.y = 0,
+    this.ax = 0,
+    this.ay = 0,
+    this.vx = 0,
+    this.vy = 0,
+    this.size = 0,
+    this.color = Colors.black,
+  });
+}

packages/idraw/lib/p18/s02.dart

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+import 'dart:math';
+
+// import 'dart:ui' as ui;
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020/11/5
+/// contact me by email 1981462002@qq.com
+/// 说明:
+
+class Paper extends StatelessWidget {
+  const Paper({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      alignment: Alignment.center,
+      child: const World(),
+    );
+  }
+}
+
+class World extends StatefulWidget {
+  const World({super.key});
+
+  @override
+  _WorldState createState() => _WorldState();
+}
+
+class _WorldState extends State<World> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  ParticleManage pm = ParticleManage();
+  Random random = Random();
+
+  @override
+  void initState() {
+    super.initState();
+    initParticleManage();
+
+    _controller = AnimationController(
+      duration: const Duration(seconds: 1),
+      vsync: this,
+    )..addListener(pm.tick)
+    // ..repeat()
+        ;
+  }
+
+  void initParticleManage() {
+    pm.size = Size(300, 200);
+    for (var i = 0; i < 30; i++) {
+      pm.particles.add(Particle(
+          color: randomRGB(),
+          size: 5 + 4 * random.nextDouble(),
+          vx: 3 * random.nextDouble() * pow(-1, random.nextInt(20)),
+          vy: 3 * random.nextDouble() * pow(-1, random.nextInt(20)),
+          ay: 0.1,
+          x: 150,
+          y: 100));
+    }
+  }
+
+  Color randomRGB({int limitR = 0, int limitG = 0, int limitB = 0,}) {
+    var r = limitR + random.nextInt(256 - limitR); //红值
+    var g = limitG + random.nextInt(256 - limitG); //绿值
+    var b = limitB + random.nextInt(256 - limitB); //蓝值
+    return Color.fromARGB(255, r, g, b); //生成argb模式的颜色
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  theWorld() {
+    if (_controller.isAnimating) {
+      _controller.stop();
+    } else {
+      _controller.repeat();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: theWorld,
+      child: CustomPaint(
+        size: pm.size,
+        painter: WorldRender(manage: pm),
+      ),
+    );
+  }
+}
+
+class ParticleManage with ChangeNotifier {
+  List<Particle> particles = [];
+
+  Size size;
+
+  ParticleManage({this.size = Size.zero});
+
+  void setParticles(List<Particle> particles) {
+    this.particles = particles;
+  }
+
+  void addParticle(Particle particle) {
+    particles.add(particle);
+    notifyListeners();
+  }
+
+  void tick() {
+    particles.forEach(doUpdate);
+    notifyListeners();
+  }
+
+  void doUpdate(Particle p) {
+    p.vy += p.ay; // y加速度变化
+    p.vx += p.ax; // x加速度变化
+    p.x += p.vx;
+    p.y += p.vy;
+    if (p.x > size.width) {
+      p.x = size.width;
+      p.vx = -p.vx;
+    }
+    if (p.x < 0) {
+      p.x = 0;
+      p.vx = -p.vx;
+    }
+    if (p.y > size.height) {
+      p.y = size.height;
+      p.vy = -p.vy;
+    }
+    if (p.y < 0) {
+      p.y = 0;
+      p.vy = -p.vy;
+    }
+  }
+
+  void reset() {
+    particles.forEach((p) {
+      p.x = 0;
+    });
+    notifyListeners();
+  }
+}
+
+class WorldRender extends CustomPainter {
+
+  final ParticleManage manage;
+
+  Paint fillPaint = Paint();
+
+  Paint stokePaint = Paint()
+    ..strokeWidth = 0.5
+    ..style = PaintingStyle.stroke;
+
+  WorldRender({required this.manage}) : super(repaint: manage);
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    canvas.drawRect(Offset.zero & size, stokePaint);
+    manage.particles.forEach((particle) {
+      drawParticle(canvas, particle);
+    });
+  }
+
+  void drawParticle(Canvas canvas, Particle particle) {
+    fillPaint.color = particle.color;
+    canvas.drawCircle(Offset(particle.x, particle.y), particle.size, fillPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant WorldRender oldDelegate) =>
+      oldDelegate.manage != manage;
+}
+
+
+class Particle {
+  /// x 位移.
+  double x;
+
+  /// y 位移.
+  double y;
+
+  /// 粒子水平速度.
+  double vx;
+
+  // 粒子水平加速度
+  double ax;
+
+  // 粒子竖直加速度
+  double ay;
+
+  ///粒子竖直速度.
+  double vy;
+
+
+  /// 粒子大小.
+  double size;
+
+  /// 粒子颜色.
+  Color color;
+
+  Particle({
+    this.x = 0,
+    this.y = 0,
+    this.ax = 0,
+    this.ay = 0,
+    this.vx = 0,
+    this.vy = 0,
+    this.size = 0,
+    this.color = Colors.black,
+  });
+}

packages/idraw/lib/p18/s03.dart

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+import 'dart:async';
+import 'dart:math';
+
+// import 'dart:ui' as ui;
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020/11/5
+/// contact me by email 1981462002@qq.com
+/// 说明:
+
+class Paper extends StatelessWidget {
+  const Paper({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      alignment: Alignment.center,
+      child: const World(),
+    );
+  }
+}
+
+class World extends StatefulWidget {
+  const World({super.key});
+
+  @override
+  _WorldState createState() => _WorldState();
+}
+
+class _WorldState extends State<World> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  ParticleManage pm = ParticleManage();
+  Random random = Random();
+  late Timer timer;
+
+  @override
+  void initState() {
+    super.initState();
+
+    pm.size = Size(300, 200);
+
+    timer =Timer.periodic(Duration(seconds: 1), (timer) {
+      if(pm.particles.length>20){
+        timer.cancel();
+      }
+      pm.addParticle(Particle(
+          color: randomRGB(),
+          size: 5 + 4 * random.nextDouble(),
+          vx: 3 * random.nextDouble() * pow(-1, random.nextInt(20)),
+          vy: 3 * random.nextDouble() * pow(-1, random.nextInt(20)),
+          ay: 0.1,
+          x: 150,
+          y: 100));
+    });
+
+    _controller = AnimationController(
+      duration: const Duration(seconds: 1),
+      vsync: this,
+    )..addListener(pm.tick)
+      ..repeat();
+  }
+
+  Color randomRGB({int limitR = 0, int limitG = 0, int limitB = 0,}) {
+    var r = limitR + random.nextInt(256 - limitR); //红值
+    var g = limitG + random.nextInt(256 - limitG); //绿值
+    var b = limitB + random.nextInt(256 - limitB); //蓝值
+    return Color.fromARGB(255, r, g, b); //生成argb模式的颜色
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    timer.cancel();
+    super.dispose();
+  }
+
+  theWorld() {
+    if (_controller.isAnimating) {
+      _controller.stop();
+    } else {
+      _controller.repeat();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: theWorld,
+      child: CustomPaint(
+        size: pm.size,
+        painter: WorldRender(manage: pm),
+      ),
+    );
+  }
+}
+
+class ParticleManage with ChangeNotifier {
+  List<Particle> particles = [];
+
+  Size size;
+
+  ParticleManage({this.size = Size.zero});
+
+  void setParticles(List<Particle> particles) {
+    this.particles = particles;
+  }
+
+  void addParticle(Particle particle) {
+    particles.add(particle);
+    notifyListeners();
+  }
+
+  void tick() {
+    particles.forEach(doUpdate);
+    notifyListeners();
+  }
+
+  void doUpdate(Particle p) {
+    p.vy += p.ay; // y加速度变化
+    p.vx += p.ax; // x加速度变化
+    p.x += p.vx;
+    p.y += p.vy;
+    if (p.x > size.width) {
+      p.x = size.width;
+      p.vx = -p.vx;
+    }
+    if (p.x < 0) {
+      p.x = 0;
+      p.vx = -p.vx;
+    }
+    if (p.y > size.height) {
+      p.y = size.height;
+      p.vy = -p.vy;
+    }
+    if (p.y < 0) {
+      p.y = 0;
+      p.vy = -p.vy;
+    }
+  }
+
+  void reset() {
+    particles.forEach((p) {
+      p.x = 0;
+    });
+    notifyListeners();
+  }
+}
+
+class WorldRender extends CustomPainter {
+
+  final ParticleManage manage;
+
+  Paint fillPaint = Paint();
+
+  Paint stokePaint = Paint()
+    ..strokeWidth = 0.5
+    ..style = PaintingStyle.stroke;
+
+  WorldRender({required this.manage}) : super(repaint: manage);
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    canvas.drawRect(Offset.zero & size, stokePaint);
+    manage.particles.forEach((particle) {
+      drawParticle(canvas, particle);
+    });
+  }
+
+  void drawParticle(Canvas canvas, Particle particle) {
+    fillPaint.color = particle.color;
+    canvas.drawCircle(Offset(particle.x, particle.y), particle.size, fillPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant WorldRender oldDelegate) =>
+      oldDelegate.manage != manage;
+}
+
+
+class Particle {
+  /// x 位移.
+  double x;
+
+  /// y 位移.
+  double y;
+
+  /// 粒子水平速度.
+  double vx;
+
+  // 粒子水平加速度
+  double ax;
+
+  // 粒子竖直加速度
+  double ay;
+
+  ///粒子竖直速度.
+  double vy;
+
+
+  /// 粒子大小.
+  double size;
+
+  /// 粒子颜色.
+  Color color;
+
+  Particle({
+    this.x = 0,
+    this.y = 0,
+    this.ax = 0,
+    this.ay = 0,
+    this.vx = 0,
+    this.vy = 0,
+    this.size = 0,
+    this.color = Colors.black,
+  });
+}

packages/idraw/lib/p18/s04.dart

@@ -0,0 +1,207 @@
+import 'dart:async';
+import 'dart:math';
+
+// import 'dart:ui' as ui;
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020/11/5
+/// contact me by email 1981462002@qq.com
+/// 说明:
+
+class Paper extends StatelessWidget {
+  const Paper({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      alignment: Alignment.center,
+      child: const World(),
+    );
+  }
+}
+
+class World extends StatefulWidget {
+  const World({super.key});
+
+  @override
+  _WorldState createState() => _WorldState();
+}
+
+class _WorldState extends State<World> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  ParticleManage pm = ParticleManage();
+  Random random = Random();
+
+  @override
+  void initState() {
+    super.initState();
+
+    pm.size = Size(300, 200);
+
+    pm.addParticle(Particle(
+        color: Colors.blue,
+        size: 50,
+        vx: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+        vy: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+        ay: 0.1,
+        ax: 0.1,
+        x: 150,
+        y: 100));
+
+    _controller = AnimationController(
+      duration: const Duration(seconds: 1),
+      vsync: this,
+    )
+      ..addListener(pm.tick)
+    // ..repeat()
+        ;
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  theWorld() {
+    if (_controller.isAnimating) {
+      _controller.stop();
+    } else {
+      _controller.repeat();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: theWorld,
+      child: CustomPaint(
+        size: pm.size,
+        painter: WorldRender(manage: pm),
+      ),
+    );
+  }
+}
+
+class ParticleManage with ChangeNotifier {
+  List<Particle> particles = [];
+
+  Size size;
+
+  ParticleManage({this.size = Size.zero});
+
+  void setParticles(List<Particle> particles) {
+    this.particles = particles;
+  }
+
+  void addParticle(Particle particle) {
+    particles.add(particle);
+    notifyListeners();
+  }
+
+  void tick() {
+    particles.forEach(doUpdate);
+    notifyListeners();
+  }
+
+  void doUpdate(Particle p) {
+    p.vy += p.ay; // y加速度变化
+    p.vx += p.ax; // x加速度变化
+    p.x += p.vx;
+    p.y += p.vy;
+    if (p.x > size.width) {
+      p.x = size.width;
+      p.vx = -p.vx;
+    }
+    if (p.x < 0) {
+      p.x = 0;
+      p.vx = -p.vx;
+    }
+    if (p.y > size.height) {
+      p.y = size.height;
+      p.vy = -p.vy;
+    }
+    if (p.y < 0) {
+      p.y = 0;
+      p.vy = -p.vy;
+    }
+  }
+
+  void reset() {
+    particles.forEach((p) {
+      p.x = 0;
+    });
+    notifyListeners();
+  }
+}
+
+class WorldRender extends CustomPainter {
+
+  final ParticleManage manage;
+
+  Paint fillPaint = Paint();
+
+  Paint stokePaint = Paint()
+    ..strokeWidth = 0.5
+    ..style = PaintingStyle.stroke;
+
+  WorldRender({required this.manage}) : super(repaint: manage);
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    canvas.drawRect(Offset.zero & size, stokePaint);
+    manage.particles.forEach((particle) {
+      drawParticle(canvas, particle);
+    });
+  }
+
+  void drawParticle(Canvas canvas, Particle particle) {
+    fillPaint.color = particle.color;
+    canvas.drawCircle(Offset(particle.x, particle.y), particle.size, fillPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant WorldRender oldDelegate) =>
+      oldDelegate.manage != manage;
+}
+
+
+class Particle {
+  /// x 位移.
+  double x;
+
+  /// y 位移.
+  double y;
+
+  /// 粒子水平速度.
+  double vx;
+
+  // 粒子水平加速度
+  double ax;
+
+  // 粒子竖直加速度
+  double ay;
+
+  ///粒子竖直速度.
+  double vy;
+
+
+  /// 粒子大小.
+  double size;
+
+  /// 粒子颜色.
+  Color color;
+
+  Particle({
+    this.x = 0,
+    this.y = 0,
+    this.ax = 0,
+    this.ay = 0,
+    this.vx = 0,
+    this.vy = 0,
+    this.size = 0,
+    this.color = Colors.black,
+  });
+}

packages/idraw/lib/p18/s05.dart

@@ -0,0 +1,244 @@
+import 'dart:async';
+import 'dart:math';
+
+// import 'dart:ui' as ui;
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:image/image.dart' as image;
+
+/// create by 张风捷特烈 on 2020/11/5
+/// contact me by email 1981462002@qq.com
+/// 说明:
+
+class Paper extends StatelessWidget {
+  const Paper({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      alignment: Alignment.center,
+      child: const World(),
+    );
+  }
+}
+class World extends StatefulWidget {
+  const World({super.key});
+
+  @override
+  _WorldState createState() => _WorldState();
+}
+
+class _WorldState extends State<World> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+  ParticleManage pm = ParticleManage();
+  Random random = Random();
+
+  @override
+  void initState() {
+    super.initState();
+
+    pm.size = Size(400, 260);
+
+    initParticles();
+
+    // pm.addParticle(Particle(
+    //     color: Colors.blue,
+    //     size: 50,
+    //     vx: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+    //     vy: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+    //     ay: 0.1,
+    //     ax: 0.1,
+    //     x: 150,
+    //     y: 100));
+
+    _controller = AnimationController(
+      duration: const Duration(seconds: 1),
+      vsync: this,
+    )..addListener(pm.tick)
+    // ..repeat()
+        ;
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  theWorld() {
+    if (_controller.isAnimating) {
+      _controller.stop();
+    } else {
+      _controller.repeat();
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      onTap: theWorld,
+      child: CustomPaint(
+        size: pm.size,
+        painter: WorldRender(manage: pm),
+      ),
+    );
+  }
+
+  void initParticles() async {
+    ByteData data = await rootBundle.load("assets/images/flutter.png");
+    List<int> bytes = data.buffer.asUint8List(data.offsetInBytes, data.lengthInBytes);
+    image.Image? imageSrc = image.decodeImage(Uint8List.fromList(bytes));
+    if(imageSrc==null) return;
+
+    double offsetX=  (pm.size.width-imageSrc.width)/2;
+    double offsetY=  (pm.size.height-imageSrc.height)/2;
+
+    for (int i = 0; i < imageSrc.width; i++) {
+      for (int j = 0; j < imageSrc.height; j++) {
+        image.PixelUint8 pixel = imageSrc.getPixel(i, j) as image.PixelUint8;
+
+        if (pixel.toString() != '(255, 255, 255, 0)') {
+          // print('-($i,$j)----${imageSrc.getPixel(i, j)}---------------');
+
+          Particle particle = Particle(
+              x: i * 1.0+ offsetX,
+              y: j * 1.0+ offsetY,
+              vx: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+              vy: 4 * random.nextDouble() * pow(-1, random.nextInt(20)),
+              ay: 0.1,
+              size: 0.5,
+              color: Colors.blue); //产生粒子---每个粒子拥有随机的一些属性信息
+
+          pm.particles.add(particle);
+        }
+      }
+    }
+    setState(() {
+
+    });
+  }
+}
+
+class ParticleManage with ChangeNotifier {
+  List<Particle> particles = [];
+
+  Size size;
+
+  ParticleManage({this.size = Size.zero});
+
+  void setParticles(List<Particle> particles) {
+    this.particles = particles;
+  }
+
+  void addParticle(Particle particle) {
+    particles.add(particle);
+    notifyListeners();
+  }
+
+  void tick() {
+    particles.forEach(doUpdate);
+    notifyListeners();
+  }
+
+  void doUpdate(Particle p) {
+    p.vy += p.ay; // y加速度变化
+    p.vx += p.ax; // x加速度变化
+    p.x += p.vx;
+    p.y += p.vy;
+    if (p.x > size.width) {
+      p.x = size.width;
+      p.vx = -p.vx;
+    }
+    if (p.x < 0) {
+      p.x = 0;
+      p.vx = -p.vx;
+    }
+    if (p.y > size.height) {
+      p.y = size.height;
+      p.vy = -p.vy;
+    }
+    if (p.y < 0) {
+      p.y = 0;
+      p.vy = -p.vy;
+    }
+  }
+
+  void reset() {
+    particles.forEach((p) {
+      p.x = 0;
+    });
+    notifyListeners();
+  }
+}
+
+class WorldRender extends CustomPainter {
+
+  final ParticleManage manage;
+
+  Paint fillPaint = Paint();
+
+  Paint stokePaint = Paint()
+    ..strokeWidth = 0.5
+    ..style = PaintingStyle.stroke;
+
+  WorldRender({required this.manage}) : super(repaint: manage);
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    // canvas.drawRect(Offset.zero&size, stokePaint);
+    manage.particles.forEach((particle) {
+      drawParticle(canvas, particle);
+    });
+  }
+
+  void drawParticle(Canvas canvas, Particle particle) {
+
+    fillPaint.color = particle.color;
+    canvas.drawCircle(Offset(particle.x, particle.y), particle.size, fillPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant WorldRender oldDelegate) =>
+      oldDelegate.manage != manage;
+}
+
+
+class Particle {
+  /// x 位移.
+  double x;
+
+  /// y 位移.
+  double y;
+
+  /// 粒子水平速度.
+  double vx;
+
+  // 粒子水平加速度
+  double ax;
+
+  // 粒子竖直加速度
+  double ay;
+
+  ///粒子竖直速度.
+  double vy;
+
+
+  /// 粒子大小.
+  double size;
+
+  /// 粒子颜色.
+  Color color;
+
+  Particle({
+    this.x = 0,
+    this.y = 0,
+    this.ax = 0,
+    this.ay = 0,
+    this.vx = 0,
+    this.vy = 0,
+    this.size = 0,
+    this.color = Colors.black,
+  });
+}