pixelToHex method
将像素坐标转换为六边形坐标
Implementation
HexCoordinate pixelToHex(Offset point) {
final m = orientation;
final pt = Offset(
(point.dx - origin.dx) / size,
(point.dy - origin.dy) / size,
);
final x = m.b0 * pt.dx + m.b1 * pt.dy;
final z = m.b2 * pt.dx + m.b3 * pt.dy;
final y = -x - z;
return _hexRound(x, y, z);
}