hex_toolkit

Description:

hex toolkit

Utilities for working with hexagons on a hexagonal grid.
Based on magnificent https://www.redblobgames.com/grids/hexagons/ article.
Zero dependencies. Framework agnostic. Use with Flutter, on Web, CLI, or anywhere Dart runs.
Example:
import 'package:hex_toolkit/hex_toolkit.dart';

void main() {
var hexA = Hex.zero();
var hexB = Hex(-5, -2, 7);

print(hexA.neighbors());
// Prints: [Hex(0, 1, -1), Hex(-1, 1, 0), Hex(-1, 0, 1), Hex(0, -1, 1), Hex(1, -1, 0), Hex(1, 0, -1)]

print(hexA.distanceTo(hexB));
// Prints: 7

print(hexA.cheapestPathTo(hexB));
// Prints: [Hex(0, 0, 0), Hex(-1, 0, 1), Hex(-2, 0, 2), Hex(-2, -1, 3), ...

print(hexA.ring(3));
// Prints: [Hex(3, -3, 0), Hex(3, -2, -1), Hex(3, -1, -2), Hex(3, 0, -3), ...

// hexA.randomHexInArea(radius)
// hexA.randomShape(50);
// hexA.randomNeighbor();
// hexA.randomNeighborWhere(filter);
}
copied to clipboard
Rendering in Flutter #
The library itself doesn't depend on Flutter, however the rendering is pretty straightforward:
class MyApp extends StatelessWidget {


const MyApp({super.key});

@override
Widget build(BuildContext context) {
return CustomPaint(
painter: HexPainter(myHexesToPain),
child: Container(),
);
}
}

class HexPainter extends CustomPainter {
static const hexSize = 20.0;
final List<Hex> toPaint;

HexPainter(this.toPaint);

@override
void paint(Canvas canvas, Size size) {
canvas.save();
// Zero in the center
canvas.translate(size.width / 2, size.height / 2);

for (var hex in toPaint) {
final paint = Paint()..color = Colors.red;

// Just get the vertices ...
var vertices = hex.vertices(hexSize).map((e) => Offset(e.x, e.y)).toList();

// ... and draw them
canvas.drawVertices(Vertices(VertexMode.triangleFan, vertices), BlendMode.plus, paint);
}
canvas.restore();
}

@override
bool shouldRepaint(covariant CustomPainter oldDelegate) => true;
}
copied to clipboard
vertices() method returns a list o 6 points, which can be easily passed to drawVertices method.
hexSize of the hex is it's "radius", see diagram at https://www.redblobgames.com/grids/hexagons/#basics
Glory to Hexagons! #

... this "world generator" is not part of the library, but it's something you can easily whip out with this toolkit.
Once again, thanks to https://www.redblobgames.com/grids/hexagons/ for the inspiration.