Behind the Scenes

In this section, you will learn how to keep your RPG or mini dungeon game clean, fancy, and modularized.

Area persistent data

You can assign data to an area during the generation process.

We can use this feature to randomize the spawner in our dungeon.

// server script
ServerEvents.recipes(event => {
    LoquatPlacements.register("any_key_you_like", new LoquatTreeNodePlacer("pack:big_dungeon", ctx => {
        // add monster rooms
        let monsterRooms = []
        // ctx.root is the start room according to the structure json file
        let lastRoom = ctx.root
        for (let i = 0; i < 5; i++) {
            // lastRoom.addChild(target_name, template_pool_name)
            monsterRooms.push(lastNode = lastRoom.addChild("door", "pack:monster"))
        }
        // add boss room
        lastRoom.addChild("door", "pack:boss")
        // add treasure room
        monsterRooms[ctx.random.nextInt(monsterRooms.length)].addChild("door", "pack:treasure")
        let spawners = ["zombies", "skeletons", "creepers"]
        monsterRooms.forEach(room => {
            // we don't want the entrance and exit to be too close, so we set a minimum distance
            room.minEdgeDistance = 8
            // we don't want two rooms are the same, so we make a unique group id for them
            room.uniqueGroup = "monster"
            room.data = {
                spawner: "pack:" + spawners[ctx.random.nextInt(spawners.length)]
            }
        })
    }))
})

LoquatEvents.playerEnteredArea(event => {
    let data = event.area.persistentData
    let tags = event.area.tags
    if (data.contains("spawner") && !tags.contains("spawned")) {
        event.player.runCommandSilent(`loquat spawn ${event.area.uuid} ${data.spawner}`)
        tags.add("spawned")
        event.areaManager.setChanged([event.area])
    }
})

The aftercare

When the players finish the level, we want to be able to clean up all the stuff that we generated, for future generations. Here is the solution:

First we need to tag all the areas that will be generated along with our structure:

// server script
ServerEvents.recipes(event => {
    LoquatPlacements.register("any_key_you_like", new LoquatTreeNodePlacer("pack:big_dungeon", ctx => {
        ctx.globalTags.add("big_dungeon")
        // ...
    }))
})

Then write code to clean them up if necessary:

// server script
function clearDungeon() {
    Utils.server.runCommandSilent(`execute in minecraft:overworld run loquat empty @a[tag=big_dungeon]`)
    Utils.server.runCommandSilent(`execute in minecraft:overworld run loquat delete @a[tag=big_dungeon]`)
}

Dynamic processor assignment

A processor list is a list of processors used to affect blocks in structures, such as replacing blocks.

You can assign a processor list to a node (piece) during the generation process.

// server script
node.lowPriorityProcessors.add(ResourceLocation.tryParse('pack:replace_diamond'))
// or node.highPriorityProcessors, depending on whether you want to
// process blocks before or after the structure is rotated and mirrored

data/pack/worldgen/processor_list/replace_diamond.json:

{
  "processors": [
    {
      "processor_type": "minecraft:rule",
      "rules": [
        {
          "input_predicate": {
            "block": "minecraft:diamond_block",
            "predicate_type": "minecraft:block_match"
          },
          "location_predicate": {
            "predicate_type": "minecraft:always_true"
          },
          "output_state": {
            "Name": "minecraft:obsidian"
          }
        }
      ]
    }
  ]
}