Fix tripwire statemap not being complete when mappings change. Closes #3924

src/main/java/net/minecraftforge/registries/GameData.java

@@ -285,6 +285,12 @@ public class GameData
             @SuppressWarnings("unchecked")
             ClearableObjectIntIdentityMap<IBlockState> blockstateMap = owner.getSlaveMap(BLOCKSTATE_TO_ID, ClearableObjectIntIdentityMap.class);
 
+            if ("minecraft:tripwire".equals(block.getRegistryName().toString())) //Tripwire is crap so we have to special case whee!
+            {
+                for (int meta = 0; meta < 15; meta++)
+                    blockstateMap.put(block.getStateFromMeta(meta), id << 4 | meta);
+            }
+
             //So, due to blocks having more in-world states then metadata allows, we have to turn the map into a semi-milti-bimap.
             //We can do this however because the implementation of the map is last set wins. So we can add all states, then fix the meta bimap.
             //Multiple states -> meta. But meta to CORRECT state.
@@ -303,7 +309,6 @@ public class GameData
                     blockstateMap.put(block.getStateFromMeta(meta), id << 4 | meta); // Put the CORRECT thing!
             }
 
-
             if (oldBlock != null)
             {
                 @SuppressWarnings("unchecked")