Gun spread overlay (#8588)

Content.Client/Weapons/Ranged/Commands/ShowSpreadCommand.cs

@@ -0,0 +1,18 @@
+using Content.Client.Weapons.Ranged.Systems;
+using Robust.Shared.Console;
+
+namespace Content.Client.Weapons.Ranged;
+
+public sealed class ShowSpreadCommand : IConsoleCommand
+{
+    public string Command => "showspread";
+    public string Description => $"Shows gun spread overlay for debugging";
+    public string Help => $"{Command}";
+    public void Execute(IConsoleShell shell, string argStr, string[] args)
+    {
+        var system = IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<GunSystem>();
+        system.SpreadOverlay ^= true;
+
+        shell.WriteLine($"Set spread overlay to {system.SpreadOverlay}");
+    }
+}

Content.Client/Weapons/Ranged/GunSpreadOverlay.cs

@@ -0,0 +1,76 @@
+using Content.Client.Weapons.Ranged.Systems;
+using Robust.Client.Graphics;
+using Robust.Client.Input;
+using Robust.Client.Player;
+using Robust.Shared.Enums;
+using Robust.Shared.Map;
+using Robust.Shared.Timing;
+
+namespace Content.Client.Weapons.Ranged;
+
+public sealed class GunSpreadOverlay : Overlay
+{
+    public override OverlaySpace Space => OverlaySpace.WorldSpace;
+
+    private IEntityManager _entManager;
+    private IEyeManager _eye;
+    private IGameTiming _timing;
+    private IInputManager _input;
+    private IPlayerManager _player;
+    private GunSystem _guns;
+
+    public GunSpreadOverlay(IEntityManager entManager, IEyeManager eyeManager, IGameTiming timing, IInputManager input, IPlayerManager player, GunSystem system)
+    {
+        _entManager = entManager;
+        _eye = eyeManager;
+        _input = input;
+        _timing = timing;
+        _player = player;
+        _guns = system;
+    }
+
+    protected override void Draw(in OverlayDrawArgs args)
+    {
+        var worldHandle = args.WorldHandle;
+
+        var player = _player.LocalPlayer?.ControlledEntity;
+
+        if (player == null ||
+            !_entManager.TryGetComponent<TransformComponent>(player, out var xform)) return;
+
+        var mapPos = xform.MapPosition;
+
+        if (mapPos.MapId == MapId.Nullspace) return;
+
+        var gun = _guns.GetGun(player.Value);
+
+        if (gun == null) return;
+
+        var mouseScreenPos = _input.MouseScreenPosition;
+        var mousePos = _eye.ScreenToMap(mouseScreenPos);
+
+        if (mapPos.MapId != mousePos.MapId) return;
+
+        // (☞ﾟヮﾟ)☞
+        var maxSpread = gun.MaxAngle;
+        var minSpread = gun.MinAngle;
+        var timeSinceLastFire = (_timing.CurTime - gun.NextFire).TotalSeconds;
+        var currentAngle = new Angle(MathHelper.Clamp(gun.CurrentAngle.Theta - gun.AngleDecay.Theta * timeSinceLastFire,
+            gun.MinAngle.Theta, gun.MaxAngle.Theta));
+        var direction = (mousePos.Position - mapPos.Position);
+
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + direction, Color.Orange);
+
+        // Show max spread either side
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + maxSpread.RotateVec(direction), Color.Red);
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + (-maxSpread).RotateVec(direction), Color.Red);
+
+        // Show min spread either side
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + minSpread.RotateVec(direction), Color.Green);
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + (-minSpread).RotateVec(direction), Color.Green);
+
+        // Show current angle
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + currentAngle.RotateVec(direction), Color.Yellow);
+        worldHandle.DrawLine(mapPos.Position, mousePos.Position + (-currentAngle).RotateVec(direction), Color.Yellow);
+    }
+}

Content.Client/Weapons/Ranged/Systems/GunSystem.cs

@@ -13,6 +13,7 @@ using Robust.Shared.Audio;
 using Robust.Shared.Input;
 using Robust.Shared.Map;
 using Robust.Shared.Player;
+using Robust.Shared.Timing;
 using Robust.Shared.Utility;
 using SharedGunSystem = Content.Shared.Weapons.Ranged.Systems.SharedGunSystem;
 
@@ -27,6 +28,34 @@ public sealed partial class GunSystem : SharedGunSystem
     [Dependency] private readonly EffectSystem _effects = default!;
     [Dependency] private readonly InputSystem _inputSystem = default!;
 
+    public bool SpreadOverlay
+    {
+        get => _spreadOverlay;
+        set
+        {
+            if (_spreadOverlay == value) return;
+            _spreadOverlay = value;
+            var overlayManager = IoCManager.Resolve<IOverlayManager>();
+
+            if (_spreadOverlay)
+            {
+                overlayManager.AddOverlay(new GunSpreadOverlay(
+                    EntityManager,
+                    IoCManager.Resolve<IEyeManager>(),
+                    IoCManager.Resolve<IGameTiming>(),
+                    IoCManager.Resolve<IInputManager>(),
+                    IoCManager.Resolve<IPlayerManager>(),
+                    this));
+            }
+            else
+            {
+                overlayManager.RemoveOverlay<GunSpreadOverlay>();
+            }
+        }
+    }
+
+    private bool _spreadOverlay;
+
     public override void Initialize()
     {
         base.Initialize();