TheriapolisV3/Theriapolis.Godot/Rendering/PlayerMarker.cs

using Godot;
using Theriapolis.Core;

namespace Theriapolis.GodotHost.Rendering;

/// <summary>
/// Player marker — small dot with a thin facing tick. Drawn at
/// <see cref="C.PLAYER_MARKER_SCREEN_PX"/>/2 wp; the owner sets
/// <see cref="Node2D.Scale"/> = 1/zoom every frame so the on-screen size
/// stays constant across the seamless zoom range. Facing is driven by
/// the owner via <see cref="Node2D.Rotation"/>; the tick is drawn along
/// the local +X axis so rotating the node rotates the tick without
/// invalidating the cached <c>_Draw</c> commands.
/// </summary>
public partial class PlayerMarker : Node2D
{
    private const float RadiusWorldPx = C.PLAYER_MARKER_SCREEN_PX * 0.5f;
    private const float FacingTickPx  = RadiusWorldPx * 1.4f;

    private bool _showFacingTick = true;

    /// <summary>When true, draws a small tick along the local +X axis
    /// so the player can read facing without a full sprite. Hidden at
    /// low zoom to avoid clutter. Triggers <see cref="CanvasItem.QueueRedraw"/>
    /// on change.</summary>
    public bool ShowFacingTick
    {
        get => _showFacingTick;
        set
        {
            if (_showFacingTick == value) return;
            _showFacingTick = value;
            QueueRedraw();
        }
    }

    public override void _Draw()
    {
        DrawCircle(Vector2.Zero, RadiusWorldPx, new Color(0, 0, 0, 0.78f));
        DrawCircle(Vector2.Zero, RadiusWorldPx * 0.85f, new Color(0.86f, 0.31f, 0.24f));

        if (_showFacingTick)
        {
            DrawLine(
                new Vector2(RadiusWorldPx * 0.4f, 0),
                new Vector2(FacingTickPx, 0),
                new Color(1f, 0.96f, 0.86f),
                width: RadiusWorldPx * 0.18f,
                antialiased: false);
        }
    }
}