用代码生成

object CrystalSpikes {
    private val CRYSTAL = Identifier.parse("mymod:crystal")

    fun register(content: ContentBuilder) {
        content.feature("crystal_spike") {
            biome("#minecraft:is_overworld")
            count = 2..5
            heights = -54..30
            on = FeatureOn.FLOOR
            underground = true
            step = FeatureStep.UNDERGROUND
            place { world ->
                val (x, y, z) = Triple(world.x, world.y, world.z)
                if (!world.isIn(x, y - 1, z, "#minecraft:base_stone_overworld")) return@place false
                val height = 2 + world.random.nextInt(4)
                for (dy in 0 until height) {
                    if (!world.isAir(x, y + dy, z)) break
                    world.set(x, y + dy, z, CRYSTAL)
                }
                true
            }
        }
    }
}

content.feature("glow_tufts") {
    biome("mymod:crystal_glade")
    everyFloor = true
    count = 4..8
    tries = 1..3
    place { world ->
        val tuft = Identifier.parse("mymod:glow_tuft")
        if (world.structures(world.x, world.z).isNotEmpty()) return@place false
        world.canStay(world.x, world.y, world.z, tuft) && world.set(world.x, world.y, world.z, tuft)
    }
}

structure "stone_ring" {
    biomes: ["#minecraft:is_overworld"]
    spacing: 32
    separation: 12
    plan: fun(p) {
        let x = p.chunk_x * 16 + 8
        let z = p.chunk_z * 16 + 8
        let y = p.height(x, z)
        return { x: x, y: y, z: z, radius: 10, min_y: y - 8, max_y: y + 12 }
    }
    build: fun(world, site) {
        for i in 0..15 {
            let a = i * pi() / 8
            let x = site.x + round(cos(a) * 10)
            let z = site.z + round(sin(a) * 10)
            if world.inside(x, z) {
                let ground = world.surface(x, z)
                for dy in 0..2 { world.set(x, ground + dy, z, "minecraft:mossy_cobblestone") }
            }
        }
    }
}

content.structure("stone_ring") {
    biome("#minecraft:is_overworld")
    spacing = 32
    separation = 12
    plan { p ->
        val x = p.chunkX * 16 + 8
        val z = p.chunkZ * 16 + 8
        val y = p.height(x, z)
        StructureSite(x, y, z, radius = 10, minY = y - 8, maxY = y + 12,
            data = mapOf("tall" to p.random.nextBoolean()))
    }
    build { world, site ->
        val stone = Identifier.parse("minecraft:mossy_cobblestone")
        val top = if (site.data["tall"] == true) 4 else 2
        for (i in 0 until 16) {
            val x = site.x + (cos(i * PI / 8) * 10).roundToInt()
            val z = site.z + (sin(i * PI / 8) * 10).roundToInt()
            if (!world.inside(x, z)) continue
            val ground = world.surface(x, z)
            for (dy in 0..top) world.set(x, ground + dy, z, stone)
        }
    }
}

val TOWER = Identifier.parse("mymod:watchtower")

content.structure("watchtower") {
    biome("minecraft:plains")
    spacing = 40
    separation = 10
    plan { p ->
        val size = p.fileSize(TOWER) ?: return@plan null
        val x = p.chunkX * 16 + 8
        val z = p.chunkZ * 16 + 8
        val y = p.height(x, z)
        StructureSite(x, y, z, radius = maxOf(size.x, size.z), minY = y, maxY = y + size.y,
            data = mapOf("turns" to p.random.nextInt(4), "half_x" to size.x / 2, "half_z" to size.z / 2))
    }
    build { world, site ->
        val hx = (site.data["half_x"] as Number).toInt()
        val hz = (site.data["half_z"] as Number).toInt()
        // Its middle on the site, turned about its middle.
        world.placeFile(TOWER, site.x - hx, site.y, site.z - hz,
            rotation = (site.data["turns"] as Number).toInt(), pivotX = hx, pivotZ = hz)
    }
}

// Rolling hills over the whole overworld.
terrain "minecraft:overworld" {
    column: fun(x, z, ys, world) {
        let ground = 72 + 14 * sin(x / 60) * cos(z / 60)
        return ys.map(fun(y) { return (ground - y) / 8 })
    }
    has_land: fun(x, z, world) { return true }
}

// Round, flattened islands in the End, one every 96 blocks.
content.terrain("minecraft:the_end") { world ->
    val shift = kotlin.random.Random(world.seed).nextInt(96)
    object : TerrainShape {
        fun across(x: Int, z: Int): Double {
            val dx = (x + shift).mod(96) - 48
            val dz = (z + shift).mod(96) - 48
            return sqrt((dx * dx + dz * dz).toDouble())
        }
        override fun column(x: Int, z: Int, ys: IntArray, out: DoubleArray) {
            val flat = across(x, z)
            for (i in ys.indices) {
                val up = (ys[i] - 64) * 2.5
                out[i] = (24 - sqrt(flat * flat + up * up)) / 24
            }
        }
        override fun hasLand(x: Int, z: Int) = across(x, z) < 24
    }
}

biome_map "minecraft:the_end" {
    biome: fun(x, y, z, land, world) {
        if x * x + z * z < 65536 { return "minecraft:the_end" }      // the central island
        if land == "minecraft:end_highlands" and (floor(x / 64) + floor(z / 64)) % 2 == 0 {
            return "mymod:crystal_glade"
        }
        return land
    }
}

content.tag(TagKind.BIOME, "glades", "crystal_glade", "ember_glade")

content.biomes("minecraft:the_end") { world ->
    val glades = world.tagged("mymod:glades")
    val theEnd = Identifier.parse("minecraft:the_end")
    BiomeMap { x, y, z, land ->
        when {
            x.toLong() * x + z.toLong() * z < 256L * 256 -> theEnd            // within 1024 blocks
            land.path != "end_highlands" || glades.isEmpty() -> land
            else -> glades[Math.floorMod((x shr 6) * 31 + (z shr 6), glades.size)]
        }
    }
}

// A round room, 6 blocks across, in some chunks.
carver "round_caves" {
    chance: 0.05
    carve: fun(ctx) {
        let cx = ctx.start_x * 16 + 8
        let cz = ctx.start_z * 16 + 8
        let cy = 20
        for x in cx - 6..cx + 6 {
            for y in cy - 6..cy + 6 {
                for z in cz - 6..cz + 6 {
                    if (x - cx) * (x - cx) + (y - cy) * (y - cy) + (z - cz) * (z - cz) <= 36 { ctx.carve(x, y, z) }
                }
            }
        }
    }
}

biome "hollow_hills" {
    replaces: "minecraft:meadow"
    carvers: ["round_caves"]
}

content.carver("round_caves", chance = 0.05) { ctx ->
    val r = ctx.random
    val cx = ctx.startX * 16 + r.nextInt(16)
    val cz = ctx.startZ * 16 + r.nextInt(16)
    val cy = r.nextInt(ctx.minY + 10, 40)
    val radius = r.nextInt(4, 9)
    for (x in cx - radius..cx + radius) for (y in cy - radius..cy + radius) for (z in cz - radius..cz + radius) {
        val (dx, dy, dz) = Triple(x - cx, y - cy, z - cz)
        if (dx * dx + dy * dy * 2 + dz * dz <= radius * radius) ctx.carve(x, y, z)
    }
}

content.biome("hollow_hills") {
    replaces = "minecraft:meadow"
    carver("round_caves")
}

biome "crystal_glade" {
    replaces: "minecraft:end_highlands"
    share: 0.3
    surface: fun(at) {
        if at.depth_above == 1 { return "mymod:crystal_moss" }
        if at.depth_above <= 3 { return "mymod:crystal_soil" }
        return null
    }
}

content.biome("crystal_glade") {
    replaces = "minecraft:end_highlands"
    share = 0.3
    surface { at ->
        val patch = at.noise("minecraft:surface", at.x.toDouble(), 0.0, at.z.toDouble()) > 0.2
        when {
            at.depthAbove == 1 && patch -> Identifier.parse("mymod:glow_moss")
            at.depthAbove == 1 -> Identifier.parse("mymod:crystal_moss")
            at.depthAbove <= 3 -> Identifier.parse("mymod:crystal_soil")
            else -> null
        }
    }
}

// Blocks a crystal can grow on, yours and the game's.
content.tag(TagKind.BLOCK, "crystal_ground", "crystal_moss", "crystal_soil", "minecraft:end_stone")
// Biomes a feature or structure can name as "#mymod:glades".
content.tag(TagKind.BIOME, "glades", "crystal_glade", "ember_glade")
// Adding to the game's: a pickaxe mines it faster.
content.tag(TagKind.BLOCK, "minecraft:mineable/pickaxe", "crystal_soil")