More optimization

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/packets/WorldPackets.java

@@ -215,11 +215,18 @@ public class WorldPackets {
                             if (section == null)
                                 continue;
 
+                            boolean willStoreAnyBlock = false;
+
                             for (int p = 0; p < section.getPalette().size(); p++) {
                                 int old = section.getPalette().get(p);
-                                section.getPalette().set(p, toNewId(old));
+                                int newId = toNewId(old);
+                                if (storage.isWelcome(newId)) {
+                                    willStoreAnyBlock = true;
+                                }
+                                section.getPalette().set(p, newId);
                             }
 
+                            if (willStoreAnyBlock) {
                                 for (int x = 0; x < 16; x++) {
                                     for (int y = 0; y < 16; y++) {
                                         for (int z = 0; z < 16; z++) {
@@ -235,6 +242,7 @@ public class WorldPackets {
                                     }
                                 }
                             }
+                        }
 
                         // Rewrite biome id 255 to plains
                         if (chunk.isBiomeData()) {