Векторы: направление, расстояние и отражение

using System;
using Reckfell;

public partial class VectorAim2D : Entity2D
{
    [Export] public bool UseMouse { get; set; } = true;
    public Vector2 OriginPoint => new(100, 270);
    public Vector2 Target { get; private set; } = new(490, 150);
    public Vector2 Offset => Target - OriginPoint;
    public Vector2 Direction => Offset.Normalized();
    private Label _status = null!;
    private bool _ru;
    private readonly Color _blue = new(0.25f, 0.46f, 1);

    public override void _Ready()
    {
        _ru = TranslationServer.GetLocale().StartsWith("ru");
        var title = new Label { Position = new Vector2(24, 20), Text = _ru
            ? "Векторы 2D: начало, цель и направление" : "2D vectors: origin, target and direction" };
        title.AddThemeFontSizeOverride("font_size", 22);
        AddChild(title);
        _status = new Label { Position = new Vector2(24, 58) };
        AddChild(_status);
        UpdateCaption();
    }

    public Error SetTarget(Vector2 target)
    {
        if (!target.IsFinite()) return Error.InvalidParameter;
        Target = target;
        if (_status is not null) UpdateCaption();
        QueueRedraw();
        return Error.Ok;
    }

    public override void _Process(double delta)
    {
        if (!UseMouse) return;
        Vector2 mouse = GetLocalMousePosition().Clamp(new Vector2(40, 115), new Vector2(600, 370));
        if (!mouse.IsEqualApprox(Target)) SetTarget(mouse);
    }

    private void UpdateCaption()
    {
        string angle = Offset.IsZeroApprox() ? "--" :
            FormattableString.Invariant($"{Mathf.RadToDeg(Vector2.Right.AngleTo(Direction)):F1}");
        _status.Text = _ru
            ? FormattableString.Invariant($"X вправо, Y вниз. Длина {Offset.Length():F1}; угол {angle}°")
            : FormattableString.Invariant($"X right, Y down. Length {Offset.Length():F1}; angle {angle}°");
    }

    private void Arrow(Vector2 from, Vector2 to, Color color)
    {
        Vector2 offset = to - from;
        if (offset.IsZeroApprox()) return;
        Vector2 direction = offset.Normalized();
        DrawLine(from, to, color, 3, true);
        DrawLine(to, to - direction.Rotated(0.45f) * 12, color, 3, true);
        DrawLine(to, to - direction.Rotated(-0.45f) * 12, color, 3, true);
    }

    public override void _Draw()
    {
        DrawRect(new Rect2(0, 0, 640, 420), new Color(0.035f, 0.04f, 0.05f));
        Arrow(OriginPoint, OriginPoint + Vector2.Right * 160, new Color(0.5f, 0.5f, 0.5f));
        Arrow(OriginPoint, OriginPoint + Vector2.Down * 90, new Color(0.3f, 0.3f, 0.3f));
        Vector2 projection = OriginPoint + Vector2.Right * Offset.Dot(Vector2.Right);
        DrawLine(Target, projection, new Color(0.3f, 0.35f, 0.45f), 1, true);
        Arrow(OriginPoint, Target, _blue);
        DrawCircle(OriginPoint, 5, Colors.White);
        DrawCircle(Target, 7, Colors.White);
    }
}