Simple wind rose impl

wind_rose.dart

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text("Роза ветров")),
        body: Center(child: WindRose()),
      ),
    );
  }
}

class WindRose extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CustomPaint(
      size: Size(300, 300),
      painter: WindRosePainter(),
    );
  }
}

class WindRosePainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    final center = Offset(size.width / 2, size.height / 2);
    final radius = min(size.width / 2, size.height / 2);
    final paint = Paint()
      ..color = Colors.red
      ..strokeWidth = 2
      ..style = PaintingStyle.stroke;

    final textStyle = TextStyle(color: Colors.black, fontSize: 14);

    // Число направлений (С, СВ, В и т.д.)
    final numDirections = 8;
    final angleStep = 2 * pi / numDirections;
    final directions = ["С", "СВ", "В", "ЮВ", "Ю", "ЮЗ", "З", "СЗ"];

    // Пример случайных данных (вы можете вставить сюда свои данные)
    final random = Random();
    final List<double> data =
        List.generate(numDirections, (_) => random.nextDouble() * radius);

    // Рисуем оси
    for (int i = 0; i < numDirections; i++) {
      final angle = i * angleStep;
      final x = center.dx + radius * cos(angle);
      final y = center.dy + radius * sin(angle);

      // Ось
      canvas.drawLine(center, Offset(x, y), paint..color = Colors.grey);

      // Подписи направлений
      final textOffset = Offset(x - 10, y - 10);
      drawText(canvas, directions[i], textOffset, textStyle);
    }

    // Рисуем многоугольник розы ветров
    final polygonPath = Path();
    for (int i = 0; i < numDirections; i++) {
      final angle = i * angleStep;
      final x = center.dx + data[i] * cos(angle);
      final y = center.dy + data[i] * sin(angle);
      if (i == 0) {
        polygonPath.moveTo(x, y);
      } else {
        polygonPath.lineTo(x, y);
      }
    }
    polygonPath.close();
    canvas.drawPath(polygonPath, paint..color = Colors.red);

    // Рисуем круговые метки
    drawCircles(canvas, center, radius, paint);
  }

  void drawText(Canvas canvas, String text, Offset position, TextStyle style) {
    final textSpan = TextSpan(text: text, style: style);
    final textPainter = TextPainter(
      text: textSpan,
      textDirection: TextDirection.ltr,
    );
    textPainter.layout(minWidth: 0, maxWidth: double.maxFinite);
    textPainter.paint(canvas, position);
  }

  // Отрисовка круговых линий для меток
  void drawCircles(Canvas canvas, Offset center, double radius, Paint paint) {
    final numCircles = 4;
    final step = radius / numCircles;

    paint.color = Colors.grey;
    paint.style = PaintingStyle.stroke;

    for (int i = 1; i <= numCircles; i++) {
      canvas.drawCircle(center, step * i, paint);
    }
  }

  @override
  bool shouldRepaint(CustomPainter oldDelegate) {
    return false;
  }
}