Hey there, I'll keep this short and sweet. I'm trying to fix this and wondered if anyone can help. I'm running code using findNearestMapStructure to find the nearest Jungle Temple and send the coordinates to the executing player. However, said method is returning null every single time. Any ideas why?

if (entity instanceof Player player && !player.getLevel().isClientSide()) {]

ServerLevel level = (ServerLevel) player.getLevel();
				HolderSet<Structure> holderset = HolderSet.direct(Structures.JUNGLE_TEMPLE);
				BlockPos pos = new BlockPos(x, y, z);
				Pair<BlockPos, Holder<Structure>> pair = level.getChunkSource().getGenerator().findNearestMapStructure(level, holderset, pos, 100, false); // This always returns null
				BlockPos structurepos = pair.getFirst();
				
				int strx = structurepos.getX();
				int stry = structurepos.getY();
				int strz = structurepos.getZ();
				
				player.displayClientMessage(Component.literal("The compass twinkles, and you sense a jungle temple at " + Integer.toString(strx) + ", " + Integer.toString(stry) + ", " + Integer.toString(strz) + "!"), (false));
                  

}

 

Your holder is for the wrong registry.

You need to get one from the active server registry.

 

This works for me based on your code:

@Mod.EventBusSubscriber(modid = MODID)
public class Events {

    @SubscribeEvent
    public static void commands(RegisterCommandsEvent event) {
        event.getDispatcher().register(Commands.literal("blah").executes(Events::blah));
    }

    public static int blah(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
        var entity = context.getSource().getEntityOrException();
        if (entity instanceof Player player && !player.getLevel().isClientSide()) {

            ServerLevel level = (ServerLevel) player.getLevel();

            // Your code using the builtin regisry which is not used at runtime
            // HolderSet<Structure> holderset = HolderSet.direct(Structures.JUNGLE_TEMPLE);

            // Code using the server registry
            Registry<Structure> registry = level.registryAccess().registryOrThrow(Registry.STRUCTURE_REGISTRY);
            HolderSet<Structure> holderSet = registry.getHolder(BuiltinStructures.JUNGLE_TEMPLE).map(HolderSet::direct).orElseThrow();

            BlockPos pos = player.blockPosition();
            Pair<BlockPos, Holder<Structure>> pair = level.getChunkSource().getGenerator().findNearestMapStructure(level, holderSet, pos, 100, false); // This always returns null
            BlockPos structurepos = pair.getFirst();
            int strx = structurepos.getX();
            int stry = structurepos.getY();
            int strz = structurepos.getZ();
            
            player.displayClientMessage(Component.literal("Location " + Integer.toString(strx) + ", " + Integer.toString(stry) + ", " + Integer.toString(strz) + "!"), (false));
        }
        return 1;
    }
}

 

Thanks so much warjort! I was just investigating and figuring this out and your comment confirmed my suspicions. I needed to get the holder directly from the registry for this to work. For anyone who finds this thread in the future, my solution was to change this line:
 

HolderSet<Structure> holderset = HolderSet.direct(Structures.JUNGLE_TEMPLE);

With this:

Registry<Structure> reg = level.registryAccess().registryOrThrow(Registry.STRUCTURE_REGISTRY);
Holder<Structure> holder = reg.getHolder((Structures.JUNGLE_TEMPLE.unwrapKey().get())).get();
HolderSet<Structure> holderset = HolderSet.direct(holder);

And voila:

Thanks for the help!