Performance improvements

Assets/Scripts/Utils/RandomUtils.cs

@@ -5,13 +5,33 @@ using Random = UnityEngine.Random;
 
 namespace Utils {
     public static class RandomUtils {
-        public static int RandomGemTypeAsInt() {
-            GemType[] spawnableGems = Enum.GetValues(typeof(GemType))
-                .Cast<GemType>()
-                .Where(gType => gType != GemType.Bomb)
-                .ToArray();
-            
-            return Random.Range(0, spawnableGems.Length);
+        private static readonly GemType[] spawnableGems = BuildSpawnableGems();
+
+        private static GemType[] BuildSpawnableGems() {
+            Array values = Enum.GetValues(typeof(GemType));
+            int count = 0;
+
+            for (int i = 0; i < values.Length; i++) {
+                if ((GemType)values.GetValue(i) != GemType.Bomb)
+                    count++;
+            }
+
+            GemType[] result = new GemType[count];
+            int write = 0;
+
+            for (int i = 0; i < values.Length; i++) {
+                GemType t = (GemType)values.GetValue(i);
+                if (t == GemType.Bomb)
+                    continue;
+
+                result[write++] = t;
+            }
+
+            return result;
+        }
+        
+        public static GemType RandomGemType() {
+            return spawnableGems[Random.Range(0, spawnableGems.Length)];
         }
     }
 }