Adds gamer flare to the game. (#4998)

Content.Client/Light/RgbLightControllerSystem.cs

@@ -0,0 +1,37 @@
+using System;
+using Content.Shared.Light;
+using Content.Shared.Light.Component;
+using Robust.Client.GameObjects;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Maths;
+using Robust.Shared.Timing;
+
+namespace Content.Client.Light
+{
+    public class RgbLightControllerSystem : EntitySystem
+    {
+        [Dependency] private IGameTiming _gameTiming = default!;
+
+        public override void Update(float frameTime)
+        {
+            base.Update(frameTime);
+            var curTime = _gameTiming.CurTime;
+            foreach (var (rgb, light, sprite) in EntityManager.EntityQuery<RgbLightControllerComponent, PointLightComponent, SpriteComponent>())
+            {
+                light.Color = GetCurrentRgbColor(curTime, TimeSpan.FromSeconds(rgb.CreationTick.Value * _gameTiming.TickPeriod.TotalSeconds), rgb);
+                sprite.Color = GetCurrentRgbColor(curTime, TimeSpan.FromSeconds(rgb.CreationTick.Value * _gameTiming.TickPeriod.TotalSeconds), rgb);
+            }
+        }
+
+        public static Color GetCurrentRgbColor(TimeSpan curTime, TimeSpan offset, RgbLightControllerComponent rgb)
+        {
+            return Color.FromHsv(new Vector4(
+                (float) (((curTime.TotalSeconds - offset.TotalSeconds) / rgb.CycleRate + Math.Abs(rgb.Owner.Uid.GetHashCode() * 0.1)) % 1),
+                1.0f,
+                1.0f,
+                1.0f
+            ));
+        }
+    }
+}