Add visual affects to Developer and Singularity items

Content/Items/Global/DeveloperRarityTooltip.cs

@@ -0,0 +1,36 @@
+using Microsoft.Xna.Framework;
+using System;
+using Terraria;
+using Terraria.ModLoader;
+using Terraria.ID;
+using System.Collections.Generic;
+
+namespace ForgottenWawiTech.Content.Items.Global
+{
+    // Appends a rainbow developer marker line to items with the Developer rarity
+    public class DeveloperRarityTooltip : GlobalItem
+    {
+        public override bool InstancePerEntity => false;
+
+        private static int DevRarityId => ModContent.RarityType<Content.Rarities.FWTDeveloperItem>();
+
+        public override void ModifyTooltips(Item item, List<TooltipLine> tooltips)
+        {
+            if (item.rare != DevRarityId)
+                return;
+
+            // Build a hue-cycling color for the tooltip text
+            float time = Main.GlobalTimeWrappedHourly;
+            // Cycle hue 0..1 over 5 seconds
+            float hue = (time / 5f) % 1f;
+            Color rainbow = Main.hslToRgb(hue, 1f, 0.5f);
+
+            var line = new TooltipLine(Mod, "DeveloperMarker", "-Developer Based Item-")
+            {
+                OverrideColor = rainbow
+            };
+
+            tooltips.Add(line);
+        }
+    }
+}