Drop chat locally, chat-bridge on velocity distributes it

- new jump blocks spawn as a small block display inside the previous block and
  interpolate position and scale to their target over 8 ticks
- the real block (plus light and particles) is placed when the display arrives,
  the display is removed afterwards

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitignore

@@ -4,3 +4,6 @@ target/
 *.iml
 .idea/workspace.xml
 forwarding.secret
+progress.properties
+progress.properties.tmp
+admins.txt

build.gradle

@@ -29,12 +29,20 @@ shadowJar {
     mergeServiceFiles()
 }
 
-// Hochladen auf den Limbo: ./gradlew uploadLimbo, danach `sudo systemctl restart limbo`
+// Hochladen auf den Limbo: ./gradlew uploadLimbo, danach `sudo systemctl restart limbo`.
+// Erst in eine Temp-Datei, Prüfsumme vergleichen, dann atomar umbenennen: ein abgebrochener Upload
+// lässt das laufende JAR unberührt, und der laufende Prozess behält bis zum Neustart sein altes JAR.
 tasks.register('uploadLimbo') {
     dependsOn shadowJar
     doLast {
+        def jar = shadowJar.archiveFile.get().asFile
+        def checksum = jar.bytes.digest('SHA-256')
         providers.exec {
-            commandLine 'scp', shadowJar.archiveFile.get().asFile.absolutePath, 'minecraft@10.20.9.3:/home/minecraft/limbo/limbo.jar'
+            commandLine 'scp', jar.absolutePath, 'minecraft@10.20.9.3:/home/minecraft/limbo/limbo.jar.new'
+        }.result.get()
+        providers.exec {
+            commandLine 'ssh', 'minecraft@10.20.9.3',
+                "cd ~/limbo && echo '${checksum}  limbo.jar.new' | sha256sum -c --quiet && mv -f limbo.jar.new limbo.jar"
         }.result.get()
     }
 }

src/main/java/eu/mhsl/minecraft/endlessjumper/Admins.java

@@ -0,0 +1,32 @@
+package eu.mhsl.minecraft.endlessjumper;
+
+import net.minestom.server.entity.Player;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Set;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+/**
+ * Admins aus admins.txt im Arbeitsverzeichnis: eine UUID pro Zeile, „#“ leitet einen Kommentar ein.
+ * Der Limbo kennt kein LuckPerms, die Datei wird aus dessen Admin-Gruppen erzeugt.
+ */
+public class Admins {
+    private static final Path FILE = Path.of("admins.txt");
+    private static Set<UUID> admins = Set.of();
+
+    public static void load() throws IOException {
+        if(!Files.exists(FILE)) return;
+        admins = Files.readAllLines(FILE).stream()
+            .map(line -> line.replaceFirst("#.*", "").trim())
+            .filter(line -> !line.isEmpty())
+            .map(UUID::fromString)
+            .collect(Collectors.toUnmodifiableSet());
+    }
+
+    public static boolean is(Player player) {
+        return admins.contains(player.getUuid());
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/BlockMath.java

@@ -1,9 +0,0 @@
-package eu.mhsl.minecraft.endlessjumper;
-
-import net.minestom.server.coordinate.Pos;
-
-public class BlockMath {
-    public static Pos roundToBlock(Pos p) {
-        return new Pos(p.blockX(), p.blockY(), p.blockZ());
-    }
-}

src/main/java/eu/mhsl/minecraft/endlessjumper/EndlessJumper.java

@@ -3,89 +3,141 @@ package eu.mhsl.minecraft.endlessjumper;
 import eu.mhsl.minecraft.endlessjumper.generator.JumpGenerator;
 import net.minestom.server.Auth;
 import net.minestom.server.MinecraftServer;
+import net.minestom.server.command.builder.Command;
+import net.minestom.server.command.builder.arguments.ArgumentType;
+import net.minestom.server.command.builder.arguments.ArgumentWord;
+import net.minestom.server.coordinate.Vec;
 import net.minestom.server.coordinate.Pos;
 import net.minestom.server.entity.Player;
 import net.minestom.server.entity.PlayerSkin;
 import net.minestom.server.event.GlobalEventHandler;
+import net.minestom.server.event.item.ItemDropEvent;
+import net.minestom.server.event.item.PickupItemEvent;
 import net.minestom.server.event.player.AsyncPlayerConfigurationEvent;
 import net.minestom.server.event.player.PlayerBlockBreakEvent;
+import net.minestom.server.event.player.PlayerBlockPlaceEvent;
+import net.minestom.server.event.player.PlayerChatEvent;
 import net.minestom.server.event.player.PlayerDisconnectEvent;
 import net.minestom.server.event.player.PlayerMoveEvent;
+import net.minestom.server.event.player.PlayerSpawnEvent;
+import net.minestom.server.event.player.PlayerSwapItemEvent;
+import net.minestom.server.event.player.PlayerUseItemEvent;
+import net.minestom.server.instance.Instance;
 import net.minestom.server.instance.InstanceContainer;
-import net.minestom.server.instance.InstanceManager;
 import net.minestom.server.instance.block.Block;
-import net.minestom.server.timer.TaskSchedule;
 
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class EndlessJumper {
+    private static final Pos START = new Pos(0, 100, 0);
+    private static final Pos SPAWN = START.add(0.5, 1, 0.5);
+    private static final Map<Player, JumpGenerator> games = new ConcurrentHashMap<>();
+
     public static void main(String[] args) throws IOException {
         MinecraftServer server = MinecraftServer.init(new Auth.Velocity(readForwardingSecret()));
-        InstanceManager instanceManager = MinecraftServer.getInstanceManager();
+        Progress.load();
+        Admins.load();
         GlobalEventHandler eventHandler = MinecraftServer.getGlobalEventHandler();
         PlayerSkin skin = PlayerSkin.fromUsername("Notch");
 
-        HashMap<Player, JumpGenerator> games = new HashMap<>();
-
         eventHandler.addListener(AsyncPlayerConfigurationEvent.class, event -> {
             final Player p = event.getPlayer();
-            p.setRespawnPoint(new Pos(0.5,101.5,0.5));
+            p.setRespawnPoint(SPAWN);
-
-            final InstanceContainer world = instanceManager.createInstanceContainer();
-            world.setGenerator(new TerrainGenerator());
-
-            Pos startingAt = new Pos(0,100,0);
-            world.setBlock(startingAt, Block.DIAMOND_BLOCK);
-
-            world.defaultClock().pause();
-            world.setTime(18000);
-
             p.setSkin(skin);
+            event.setSpawningInstance(createWorld());
+        });
 
-            event.setSpawningInstance(world);
+        eventHandler.addListener(PlayerSpawnEvent.class, event -> {
-
+            if(!event.isFirstSpawn()) return;
-            MinecraftServer.getSchedulerManager().scheduleTask(
+            Player p = event.getPlayer();
-                () -> games.put(p, new JumpGenerator(startingAt, p, world)),
+            p.setCanPickupItem(true);
-                TaskSchedule.seconds(3),
+            ScoreTab.join(p);
-                TaskSchedule.stop()
+            Jokers.clear(p);
-            );
+            // sobald der Spieler in der Welt steht, geht es los
+            games.put(p, new JumpGenerator(START, Progress.checkpoint(p.getUuid()), p, p.getInstance()));
         });
 
         eventHandler.addListener(PlayerMoveEvent.class, event -> {
-            Player p = event.getPlayer();
+            JumpGenerator generator = games.get(event.getPlayer());
-
+            if(generator == null) event.setCancelled(true);
-            if(!games.containsKey(p)) {
+            else generator.onMove(event.getNewPosition());
-                event.setCancelled(true);
-                return;
-            }
-
-            JumpGenerator generator = games.get(p);
-
-            //reset when falling down
-            if(p.getPosition().y() < generator.getNextLanding().y()-5 && p.getPosition().y() < generator.getCheckpoint().y()) generator.reset();
-
-            Pos p1 = BlockMath.roundToBlock(event.getNewPosition().sub(0.0,1.0,0.0));
-            Pos p2 = BlockMath.roundToBlock(event.getNewPosition().sub(0.0, 2.0, 0.0));
-
-
-            for(int i = 0; i <= generator.getPreview(); i++) {
-                Pos target = generator.getBlocks().get(generator.getBlocks().size()-i-1);
-                if(p1.sameBlock(target) || p2.sameBlock(target)) generator.generateNext();
-            }
-
-
-            //if(p.getPosition().z() > target.z()+2) generator.highlight();
         });
 
         eventHandler.addListener(PlayerBlockBreakEvent.class, event -> event.setCancelled(true));
+        eventHandler.addListener(PlayerBlockPlaceEvent.class, event -> event.setCancelled(true));
+        eventHandler.addListener(ItemDropEvent.class, event -> event.setCancelled(true));
+        eventHandler.addListener(PlayerSwapItemEvent.class, event -> event.setCancelled(true));
+        // den Chat verteilt Velocity (chat-bridge) an das ganze Netzwerk, hier würde er doppelt stehen
+        eventHandler.addListener(PlayerChatEvent.class, event -> event.setCancelled(true));
 
-        eventHandler.addListener(PlayerDisconnectEvent.class, event -> games.remove(event.getPlayer()));
+        // der Client meldet Rechtsklicks auch auf Blöcke als Item-Nutzung, solange der Block sie nicht
+        // selbst verarbeitet (auf der Strecke nie) – ein Event genügt, Joker werden nicht doppelt verbraucht
+        eventHandler.addListener(PlayerUseItemEvent.class, event -> {
+            JumpGenerator generator = games.get(event.getPlayer());
+            Jokers joker = Jokers.of(event.getItemStack());
+            if(generator != null && joker != null && generator.useJoker(joker)) joker.take(event.getPlayer());
+        });
+
+        eventHandler.addListener(PickupItemEvent.class, event -> {
+            Jokers joker = Jokers.of(event.getItemStack());
+            if(event.getLivingEntity() instanceof Player player && joker != null) joker.add(player);
+            else event.setCancelled(true);
+        });
+
+        eventHandler.addListener(PlayerDisconnectEvent.class, event -> {
+            Player p = event.getPlayer();
+            games.remove(p);
+            ScoreTab.leave(p);
+            // jede Partie hat eine eigene Welt: nach dem Verlassen freigeben
+            releaseLater(p.getInstance());
+        });
+
+        Command reset = new Command("reset");
+        reset.setDefaultExecutor((sender, context) -> {
+            if(sender instanceof Player player) resetGame(player);
+        });
+        MinecraftServer.getCommandManager().register(reset);
+
+        // nur für Admins (admins.txt): Joker zum Testen direkt geben
+        Command joker = new Command("joker");
+        joker.setCondition((sender, commandString) -> sender instanceof Player player && Admins.is(player));
+        ArgumentWord type = ArgumentType.Word("typ").from(Jokers.keys());
+        joker.addSyntax((sender, context) -> Jokers.byKey(context.get(type)).add((Player) sender), type);
+        MinecraftServer.getCommandManager().register(joker);
 
         server.start("0.0.0.0", 25501);
+    }
 
+    private static InstanceContainer createWorld() {
+        InstanceContainer world = MinecraftServer.getInstanceManager().createInstanceContainer();
+        world.setBlock(START, Block.DIAMOND_BLOCK);
+        // Tageszeit steuert der jeweilige Abschnitt
+        world.defaultClock().pause();
+        return world;
+    }
+
+    private static void releaseLater(Instance world) {
+        if(world != null) MinecraftServer.getSchedulerManager().scheduleNextTick(() -> MinecraftServer.getInstanceManager().unregisterInstance(world));
+    }
+
+    /** /reset: Fortschritt, Strecke, Score und Joker zurücksetzen und in einer frischen Welt bei 0 beginnen. */
+    private static void resetGame(Player player) {
+        JumpGenerator old = games.remove(player);
+        if(old != null) old.close();
+        Progress.reset(player.getUuid());
+
+        Instance oldWorld = player.getInstance();
+        InstanceContainer world = createWorld();
+        player.setVelocity(Vec.ZERO);
+        player.setInstance(world, SPAWN).thenRun(() -> {
+            Jokers.clear(player);
+            games.put(player, new JumpGenerator(START, 0, player, world));
+            releaseLater(oldWorld);
+        });
     }
 
     // Wie bei Velocity: Secret aus forwarding.secret im Arbeitsverzeichnis, alternativ per Umgebungsvariable

src/main/java/eu/mhsl/minecraft/endlessjumper/Jokers.java

@@ -0,0 +1,87 @@
+package eu.mhsl.minecraft.endlessjumper;
+
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.format.TextColor;
+import net.kyori.adventure.text.format.TextDecoration;
+import net.minestom.server.entity.Player;
+import net.minestom.server.item.ItemStack;
+import net.minestom.server.item.Material;
+
+import java.util.Random;
+
+/**
+ * Joker-Items in der Hotbar, die Anzahl ist die Stapelgröße. Es gibt sie zum Einsammeln auf der
+ * Strecke; wer bei 0 beginnt, bekommt ein Totem. Das Totem wirkt automatisch, die anderen per Rechtsklick (siehe JumpGenerator#useJoker).
+ */
+public enum Jokers {
+    BRIDGE("bruecke", 0, Material.BRICK, "Brücke", NamedTextColor.AQUA, "Rechtsklick: Weg über die nächsten 10 Blöcke"),
+    FEATHER_FALL("federfall", 1, Material.FEATHER, "Federfall", NamedTextColor.WHITE, "Rechtsklick: 15 Sekunden langsames Fallen"),
+    SPRING("sprungfeder", 2, Material.RABBIT_FOOT, "Sprungfeder", NamedTextColor.GREEN, "Rechtsklick: die nächsten 10 Sprünge mit Sprungkraft"),
+    TOTEM("totem", 8, Material.TOTEM_OF_UNDYING, "Rettungstotem", NamedTextColor.GOLD, "Rettet dich automatisch beim Runterfallen");
+
+    // Name im Befehl /joker (Brigadier erlaubt keine Umlaute)
+    private final String key;
+    private final int slot;
+    private final String name;
+    private final ItemStack item;
+
+    Jokers(String key, int slot, Material material, String name, TextColor color, String lore) {
+        this.key = key;
+        this.slot = slot;
+        this.name = name;
+        this.item = ItemStack.builder(material)
+            .customName(Component.text(name, color).decoration(TextDecoration.ITALIC, false))
+            .lore(Component.text(lore, NamedTextColor.GRAY).decoration(TextDecoration.ITALIC, false))
+            .build();
+    }
+
+    public ItemStack item() {
+        return this.item;
+    }
+
+    public boolean matches(ItemStack stack) {
+        return stack.material() == this.item.material();
+    }
+
+    public void add(Player player) {
+        player.getInventory().replaceItemStack(this.slot, current -> this.matches(current) ? current.withAmount(a -> a + 1) : this.item);
+        player.sendMessage(Component.text("+1 " + this.name, NamedTextColor.GOLD));
+    }
+
+    /** Nimmt einen Joker weg; false, wenn keiner mehr da ist. */
+    public boolean take(Player player) {
+        if(!this.matches(player.getInventory().getItemStack(this.slot))) return false;
+        player.getInventory().replaceItemStack(this.slot, current -> current.consume(1));
+        return true;
+    }
+
+    /** Zum Start (und nach /reset) gibt es keine Joker. */
+    public static void clear(Player player) {
+        for(Jokers joker : values()) player.getInventory().setItemStack(joker.slot, ItemStack.AIR);
+    }
+
+    public static Jokers random(Random random) {
+        return values()[random.nextInt(values().length)];
+    }
+
+    public static String[] keys() {
+        String[] keys = new String[values().length];
+        for(Jokers joker : values()) keys[joker.ordinal()] = joker.key;
+        return keys;
+    }
+
+    public static Jokers byKey(String key) {
+        for(Jokers joker : values()) {
+            if(joker.key.equals(key)) return joker;
+        }
+        return null;
+    }
+
+    public static Jokers of(ItemStack stack) {
+        for(Jokers joker : values()) {
+            if(joker.matches(stack)) return joker;
+        }
+        return null;
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/Progress.java

@@ -0,0 +1,59 @@
+package eu.mhsl.minecraft.endlessjumper;
+
+import net.minestom.server.MinecraftServer;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
+import java.util.Properties;
+import java.util.UUID;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+/**
+ * Letzter erreichter Checkpoint pro Spieler, damit man beim nächsten Besuch dort weiterspielt.
+ * Liegt als progress.properties im Arbeitsverzeichnis; für ein neues Projekt einfach löschen.
+ */
+public class Progress {
+    private static final Path FILE = Path.of("progress.properties");
+    private static final Path TEMP = Path.of("progress.properties.tmp");
+    // Properties ist synchronisiert; geschrieben wird nacheinander außerhalb des Server-Ticks
+    private static final Properties checkpoints = new Properties();
+    private static final ExecutorService writer = Executors.newSingleThreadExecutor(Thread.ofVirtual().factory());
+
+    public static void load() throws IOException {
+        if(!Files.exists(FILE)) return;
+        try(Reader reader = Files.newBufferedReader(FILE)) {
+            checkpoints.load(reader);
+        }
+    }
+
+    public static int checkpoint(UUID player) {
+        return Integer.parseInt(checkpoints.getProperty(player.toString(), "0"));
+    }
+
+    public static void save(UUID player, int checkpoint) {
+        checkpoints.setProperty(player.toString(), String.valueOf(checkpoint));
+        writer.execute(Progress::write);
+    }
+
+    public static void reset(UUID player) {
+        checkpoints.remove(player.toString());
+        writer.execute(Progress::write);
+    }
+
+    /** Erst in eine Temp-Datei, dann atomar umbenennen: ein Absturz hinterlässt nie eine halbe Datei. */
+    private static void write() {
+        try {
+            try(Writer out = Files.newBufferedWriter(TEMP)) {
+                checkpoints.store(out, "EndlessJumper: letzter Checkpoint pro Spieler");
+            }
+            Files.move(TEMP, FILE, StandardCopyOption.REPLACE_EXISTING, StandardCopyOption.ATOMIC_MOVE);
+        } catch(IOException e) {
+            MinecraftServer.getExceptionManager().handleException(e);
+        }
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/ScoreTab.java

@@ -0,0 +1,27 @@
+package eu.mhsl.minecraft.endlessjumper;
+
+import net.minestom.server.entity.Player;
+import net.minestom.server.network.packet.server.play.ScoreboardObjectivePacket;
+import net.minestom.server.scoreboard.TabList;
+
+/**
+ * Zeigt den aktuellen Fortschritt jedes Spielers als Zahl in der Tab-Liste.
+ * Der Fortschritt ist zugleich das Level des Spielers, daher braucht es keinen eigenen Speicher.
+ */
+public class ScoreTab {
+    private static final TabList TAB_LIST = new TabList("jumps", ScoreboardObjectivePacket.Type.INTEGER);
+
+    public static void join(Player player) {
+        TAB_LIST.addViewer(player);
+        // dem neuen Spieler auch die Scores aller anderen zeigen
+        TAB_LIST.getViewers().forEach(viewer -> TAB_LIST.updateScore(viewer, viewer.getLevel()));
+    }
+
+    public static void update(Player player, int score) {
+        if(TAB_LIST.getViewers().contains(player)) TAB_LIST.updateScore(player, score);
+    }
+
+    public static void leave(Player player) {
+        TAB_LIST.removeViewer(player);
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/TerrainGenerator.java

@@ -1,12 +0,0 @@
-package eu.mhsl.minecraft.endlessjumper;
-
-import net.minestom.server.instance.generator.GenerationUnit;
-import net.minestom.server.instance.generator.Generator;
-import org.jetbrains.annotations.NotNull;
-
-public class TerrainGenerator implements Generator {
-    @Override
-    public void generate(@NotNull GenerationUnit unit) {
-
-    }
-}

src/main/java/eu/mhsl/minecraft/endlessjumper/generator/BlockPalette.java

@@ -1,77 +1,111 @@
 package eu.mhsl.minecraft.endlessjumper.generator;
 
 import net.minestom.server.instance.block.Block;
+import net.minestom.server.particle.Particle;
+import net.minestom.server.sound.SoundEvent;
 
 import java.util.List;
+import java.util.Map;
 import java.util.Random;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
- * Block-Themen entlang des Fortschritts: einmal durch das komplette Spiel,
+ * Abschnitte entlang des Fortschritts: einmal durch das komplette Spiel, von der Wiese über
- * von der Wiese über Untergrund, Nether und Stronghold bis ins End (ab Sprung 1000).
+ * Untergrund, Nether und Stronghold bis ins End; ab Sprung 1000 geht es endlos weiter, alle 50 Sprünge
+ * mit einem zufälligen Thema aus diesen Abschnitten. Jeder Abschnitt hat eigene
+ * Blöcke und eine eigene Stimmung (Tageszeit, Partikel, Musik).
  */
 public class BlockPalette {
-    public record Stage(int from, String name, List<Block> blocks) {
+    /** @param ambient Partikel um den Spieler, {@code null} für keine */
+    public record Stage(int from, String name, long time, Particle ambient, SoundEvent music, List<Block> blocks) {
     }
 
-    public static final List<Stage> STAGES = List.of(
+    private static final long MORNING = 1000, NOON = 6000, NIGHT = 18000;
-        new Stage(0, "Wiese", List.of(
+
+    private static final List<Stage> STAGES = List.of(
+        new Stage(0, "Wiese", MORNING, null, SoundEvent.MUSIC_OVERWORLD_MEADOW, List.of(
             Block.GRASS_BLOCK, Block.GRASS_BLOCK, Block.MOSS_BLOCK, Block.PODZOL, Block.ROOTED_DIRT
         )),
-        new Stage(75, "Wald", List.of(
+        new Stage(70, "Wald", NOON, Particle.CHERRY_LEAVES, SoundEvent.MUSIC_OVERWORLD_FOREST, List.of(
             Block.OAK_LOG, Block.BIRCH_LOG, Block.SPRUCE_LOG, Block.CHERRY_LOG,
             Block.OAK_LEAVES, Block.BIRCH_LEAVES, Block.SPRUCE_LEAVES, Block.CHERRY_LEAVES
         )),
-        new Stage(150, "Untergrund", List.of(
+        new Stage(140, "Untergrund", NIGHT, null, SoundEvent.MUSIC_OVERWORLD_DRIPSTONE_CAVES, List.of(
             Block.DIRT, Block.COARSE_DIRT, Block.STONE, Block.STONE, Block.ANDESITE,
             Block.GRANITE, Block.DIORITE, Block.COBBLESTONE
         )),
-        new Stage(250, "Höhlen", List.of(
+        new Stage(220, "Höhlen", NIGHT, Particle.DRIPPING_WATER, SoundEvent.MUSIC_OVERWORLD_LUSH_CAVES, List.of(
             Block.STONE, Block.COAL_ORE, Block.IRON_ORE, Block.COPPER_ORE,
             Block.GOLD_ORE, Block.REDSTONE_ORE, Block.LAPIS_ORE
         )),
-        new Stage(350, "Tiefenschiefer", List.of(
+        new Stage(300, "Tiefenschiefer", NIGHT, Particle.SCULK_SOUL, SoundEvent.MUSIC_OVERWORLD_DEEP_DARK, List.of(
             Block.DEEPSLATE, Block.DEEPSLATE, Block.TUFF, Block.DEEPSLATE_DIAMOND_ORE,
             Block.DEEPSLATE_IRON_ORE, Block.AMETHYST_BLOCK
         )),
-        new Stage(450, "Netherportal", List.of(
+        new Stage(390, "Netherportal", NIGHT, Particle.PORTAL, SoundEvent.MUSIC_NETHER_NETHER_WASTES, List.of(
             Block.OBSIDIAN, Block.OBSIDIAN, Block.CRYING_OBSIDIAN
         )),
-        new Stage(475, "Nether", List.of(
+        new Stage(410, "Nether", NIGHT, Particle.CRIMSON_SPORE, SoundEvent.MUSIC_NETHER_CRIMSON_FOREST, List.of(
             Block.NETHERRACK, Block.NETHERRACK, Block.CRIMSON_NYLIUM, Block.WARPED_NYLIUM,
             Block.SOUL_SOIL, Block.GLOWSTONE, Block.NETHER_QUARTZ_ORE, Block.NETHER_GOLD_ORE
         )),
-        new Stage(625, "Festung & Bastion", List.of(
+        new Stage(540, "Festung & Bastion", NIGHT, Particle.WHITE_ASH, SoundEvent.MUSIC_NETHER_BASALT_DELTAS, List.of(
             Block.NETHER_BRICKS, Block.RED_NETHER_BRICKS, Block.BLACKSTONE,
             Block.POLISHED_BLACKSTONE_BRICKS, Block.GILDED_BLACKSTONE, Block.BASALT
         )),
-        new Stage(750, "Stronghold", List.of(
+        new Stage(660, "Stronghold", NIGHT, Particle.ENCHANT, SoundEvent.MUSIC_DISC_MELLOHI, List.of(
             Block.STONE_BRICKS, Block.MOSSY_STONE_BRICKS, Block.CRACKED_STONE_BRICKS,
             Block.CHISELED_STONE_BRICKS, Block.BOOKSHELF
         )),
-        new Stage(925, "Portalraum", List.of(
+        new Stage(800, "Portalraum", NIGHT, Particle.REVERSE_PORTAL, SoundEvent.MUSIC_DRAGON, List.of(
             Block.END_PORTAL_FRAME, Block.END_PORTAL_FRAME.withProperty("eye", "true"),
             Block.STONE_BRICKS, Block.MOSSY_STONE_BRICKS
         )),
-        new Stage(1000, "End", List.of(
+        new Stage(850, "End", NIGHT, Particle.END_ROD, SoundEvent.MUSIC_END, List.of(
             Block.END_STONE, Block.END_STONE, Block.END_STONE_BRICKS,
             Block.PURPUR_BLOCK, Block.PURPUR_PILLAR, Block.OBSIDIAN
         ))
     );
 
+    // ab hier endlos: alle ENDLESS_SEGMENT Sprünge ein zufälliges Thema aus den Abschnitten oben
+    private static final int ENDLESS_FROM = 1000;
+    private static final int ENDLESS_SEGMENT = 50;
+    private static final Map<Integer, Stage> endlessStages = new ConcurrentHashMap<>();
+
     public static Stage stageAt(int index) {
-        Stage current = STAGES.getFirst();
+        if(index >= ENDLESS_FROM) return endlessStage((index - ENDLESS_FROM) / ENDLESS_SEGMENT);
-        for(Stage stage : STAGES) {
+        for(Stage stage : STAGES.reversed()) {
-            if(index >= stage.from()) current = stage;
+            if(index >= stage.from()) return stage;
         }
-        return current;
+        return STAGES.getFirst();
     }
 
-    /** Liefert die Stufe, die genau bei diesem Index beginnt, sonst null. */
+    public static boolean isEndless(Stage stage) {
-    public static Stage stageStartingAt(int index) {
+        return stage.from() >= ENDLESS_FROM;
-        for(Stage stage : STAGES) {
-            if(stage.from() == index) return stage;
     }
-        return null;
+
+    /**
+     * Thema eines endlosen Abschnitts. Fest an die Abschnittsnummer gebunden (gleiches Thema beim
+     * Weiterspielen) und nie zweimal dasselbe hintereinander. Zwischengespeichert, damit jeder
+     * Abschnitt genau ein Stage-Objekt hat (Abschnittswechsel werden per Identität erkannt).
+     */
+    private static Stage endlessStage(int segment) {
+        return endlessStages.computeIfAbsent(segment, n -> {
+            Stage theme = themeOf(n);
+            return new Stage(ENDLESS_FROM + n * ENDLESS_SEGMENT, "Unendlich · " + theme.name(), theme.time(), theme.ambient(), theme.music(), theme.blocks());
+        });
+    }
+
+    /** Würfelt die Themen ab Abschnitt 0 der Reihe nach, damit „nie zweimal hintereinander“ sicher gilt. */
+    private static Stage themeOf(int segment) {
+        int previous = -1;
+        int pick = 0;
+        for(int n = 0; n <= segment; n++) {
+            pick = new Random(n * 31L + 7).nextInt(STAGES.size());
+            if(pick == previous) pick = (pick + 1) % STAGES.size();
+            previous = pick;
+        }
+        return STAGES.get(pick);
     }
 
     public static Block getRandom(int index, Random random) {

src/main/java/eu/mhsl/minecraft/endlessjumper/generator/BlockTransition.java

@@ -0,0 +1,61 @@
+package eu.mhsl.minecraft.endlessjumper.generator;
+
+import net.minestom.server.coordinate.Pos;
+import net.minestom.server.coordinate.Vec;
+import net.minestom.server.entity.Entity;
+import net.minestom.server.entity.EntityType;
+import net.minestom.server.entity.metadata.display.BlockDisplayMeta;
+import net.minestom.server.instance.Instance;
+import net.minestom.server.instance.block.Block;
+import net.minestom.server.timer.TaskSchedule;
+
+/**
+ * Lässt einen neuen Block als Block-Display klein oben aus dem vorherigen Block herauswachsen
+ * und zu seiner Zielposition gleiten. Erst bei Ankunft wird der echte Block gesetzt.
+ */
+public class BlockTransition {
+    public static final int DURATION_TICKS = 8;
+    /** Zeit vom Start bis der echte Block steht (Spawn-Vorlauf + Animation + Puffer). */
+    public static final int TOTAL_TICKS = DURATION_TICKS + 3;
+    private static final double START_SCALE = 0.3;
+    // minimal kleiner als der Block: sobald der echte Block steht, verdeckt er das Display ohne Z-Fighting
+    private static final double END_SCALE = 0.998;
+    // der Client braucht nach dem Setzen ein, zwei Frames bis der Block sichtbar ist: so lange bleibt das Display
+    private static final int OVERLAP_TICKS = 4;
+
+    public static void animate(Instance world, Pos from, Pos to, Block block, int delayTicks, Runnable onArrival) {
+        world.scheduler().buildTask(() -> spawn(world, from, to, block, onArrival))
+            .delay(TaskSchedule.tick(Math.max(1, delayTicks)))
+            .schedule();
+    }
+
+    private static void spawn(Instance world, Pos from, Pos to, Block block, Runnable onArrival) {
+        Entity display = new Entity(EntityType.BLOCK_DISPLAY);
+        display.setNoGravity(true);
+        display.editEntityMeta(BlockDisplayMeta.class, meta -> {
+            meta.setBlockState(block);
+            // feste Helligkeit: das Display startet im vorherigen Block, dort ist Lichtstufe 0 (sonst schwarz)
+            meta.setBrightness(15, 15);
+            meta.setPosRotInterpolationDuration(DURATION_TICKS);
+            meta.setTransformationInterpolationDuration(DURATION_TICKS);
+            // klein und mittig auf der Oberseite des vorherigen Blocks starten
+            meta.setScale(new Vec(START_SCALE));
+            meta.setTranslation(new Vec((1 - START_SCALE) / 2, 1, (1 - START_SCALE) / 2));
+        });
+
+        display.setInstance(world, from).thenRun(() -> {
+            // kurz warten, damit der Client das Display kennt, bevor die Interpolation startet
+            display.scheduler().buildTask(() -> {
+                display.editEntityMeta(BlockDisplayMeta.class, meta -> {
+                    meta.setTransformationInterpolationStartDelta(0);
+                    meta.setScale(new Vec(END_SCALE));
+                    meta.setTranslation(new Vec((1 - END_SCALE) / 2));
+                });
+                display.teleport(to);
+            }).delay(TaskSchedule.tick(2)).schedule();
+
+            display.scheduler().buildTask(onArrival).delay(TaskSchedule.tick(TOTAL_TICKS)).schedule();
+            display.scheduler().buildTask(display::remove).delay(TaskSchedule.tick(TOTAL_TICKS + OVERLAP_TICKS)).schedule();
+        });
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/generator/Fireworks.java

@@ -0,0 +1,50 @@
+package eu.mhsl.minecraft.endlessjumper.generator;
+
+import net.kyori.adventure.util.RGBLike;
+import net.minestom.server.color.Color;
+import net.minestom.server.component.DataComponents;
+import net.minestom.server.coordinate.Pos;
+import net.minestom.server.coordinate.Vec;
+import net.minestom.server.entity.Entity;
+import net.minestom.server.entity.EntityType;
+import net.minestom.server.entity.metadata.projectile.FireworkRocketMeta;
+import net.minestom.server.instance.Instance;
+import net.minestom.server.item.ItemStack;
+import net.minestom.server.item.Material;
+import net.minestom.server.item.component.FireworkExplosion;
+import net.minestom.server.item.component.FireworkList;
+import net.minestom.server.timer.TaskSchedule;
+
+import java.util.List;
+import java.util.Random;
+
+/** Steigt eine Feuerwerksrakete auf und explodiert in zufälliger Form und Farbe. */
+class Fireworks {
+    private static final List<RGBLike> COLORS = List.of(
+        new Color(255, 85, 85), new Color(255, 170, 0), new Color(255, 255, 85),
+        new Color(85, 255, 85), new Color(85, 255, 255), new Color(85, 85, 255), new Color(255, 85, 255)
+    );
+    private static final int FLIGHT_TICKS = 20;
+
+    static void launch(Instance world, Pos at, Random random) {
+        FireworkExplosion.Shape[] shapes = FireworkExplosion.Shape.values();
+        FireworkExplosion explosion = new FireworkExplosion(
+            shapes[random.nextInt(shapes.length)],
+            List.of(COLORS.get(random.nextInt(COLORS.size())), COLORS.get(random.nextInt(COLORS.size()))),
+            List.of(COLORS.get(random.nextInt(COLORS.size()))),
+            random.nextBoolean(),
+            random.nextBoolean()
+        );
+        ItemStack rocketItem = ItemStack.of(Material.FIREWORK_ROCKET).with(DataComponents.FIREWORKS, new FireworkList(1, List.of(explosion)));
+
+        Entity rocket = new Entity(EntityType.FIREWORK_ROCKET);
+        rocket.setNoGravity(true);
+        rocket.editEntityMeta(FireworkRocketMeta.class, meta -> meta.setFireworkInfo(rocketItem));
+        rocket.setVelocity(new Vec(0, 15, 0));
+        rocket.setInstance(world, at).thenRun(() -> rocket.scheduler().buildTask(() -> {
+            // Status 17: der Client zeigt die Explosion
+            rocket.triggerStatus((byte) 17);
+            rocket.remove();
+        }).delay(TaskSchedule.tick(FLIGHT_TICKS)).schedule());
+    }
+}

src/main/java/eu/mhsl/minecraft/endlessjumper/generator/JumpGenerator.java

@@ -1,140 +1,408 @@
 package eu.mhsl.minecraft.endlessjumper.generator;
 
+import eu.mhsl.minecraft.endlessjumper.Jokers;
+import eu.mhsl.minecraft.endlessjumper.Progress;
+import eu.mhsl.minecraft.endlessjumper.ScoreTab;
 import net.kyori.adventure.sound.Sound;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
 import net.kyori.adventure.text.format.TextColor;
 import net.kyori.adventure.title.Title;
+import net.minestom.server.coordinate.Point;
 import net.minestom.server.coordinate.Pos;
+import net.minestom.server.coordinate.Vec;
+import net.minestom.server.entity.ItemEntity;
 import net.minestom.server.entity.Player;
-import net.minestom.server.instance.InstanceContainer;
+import net.minestom.server.instance.Chunk;
+import net.minestom.server.instance.Instance;
 import net.minestom.server.instance.block.Block;
 import net.minestom.server.network.packet.server.play.ParticlePacket;
 import net.minestom.server.particle.Particle;
+import net.minestom.server.potion.Potion;
+import net.minestom.server.potion.PotionEffect;
 import net.minestom.server.sound.SoundEvent;
+import net.minestom.server.timer.TaskSchedule;
 
+import java.time.Duration;
 import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.Random;
 
+/**
+ * Eine Partie Jump'n'Run. Die Strecke ist eine Liste von Schritten; {@link #standing} ist der Index
+ * des zuletzt erreichten Blocks und zugleich der Score. Vorgeneriert werden {@link #PREVIEW} Blöcke
+ * über den nächsten Landeblock hinaus.
+ */
 public class JumpGenerator {
-    private final Player player;
+    private record Step(Pos pos, Block block) {
-    private final InstanceContainer world;
+    }
-    private final ArrayList<Pos> blocks = new ArrayList<>();
-    private Pos checkpoint;
-    private Pos starting;
 
-    private int combo = 0;
+    private record BlockKey(int x, int y, int z) {
-
+        static BlockKey of(Point point) {
-    private final int preview = 2;
+            return new BlockKey(point.blockX(), point.blockY(), point.blockZ());
+        }
+    }
 
+    private static final int PREVIEW = 3;
     private static final int FULL_DIFFICULTY_AT = 1000;
+    private static final int FINALE_AT = 1000;
+    private static final int FIREWORKS_NEAR = 6, FIREWORKS_FAR = 14, FIREWORKS_SPAN_TICKS = 100;
 
+    private static final Block BRIDGE_BLOCK = Block.WHITE_STAINED_GLASS;
+    private static final int BRIDGE_STEP_TICKS = 4;
+    private static final int BRIDGE_LENGTH = 10;
+    private static final Block RESCUE_BLOCK = Block.OAK_PLANKS;
+    private static final int RESCUE_DEPTH = 6;
+    private static final int FEATHER_FALL_TICKS = 15 * 20;
+    private static final int SPRING_JUMPS = 10;
+    private static final double CHECKPOINT_JOKER_CHANCE = 0.1;
 
-    public JumpGenerator(Pos starting, Player player, InstanceContainer world) {
+    private static final TextColor COMBO_COLOR = TextColor.color(255, 69, 0);
+    private static final Title CHECKPOINT_TITLE = Title.title(Component.empty(), Component.text("Checkpoint", NamedTextColor.GREEN));
+    private static final Title FINALE_TITLE = Title.title(Component.text("Geschafft!", NamedTextColor.GOLD), Component.text("Durchgespielt – ab jetzt geht es endlos weiter", NamedTextColor.YELLOW));
+    private static final Sound CHECKPOINT_SOUND = Sound.sound(SoundEvent.ENTITY_PLAYER_LEVELUP, Sound.Source.BLOCK, 0.3f, 1f);
+    private static final Sound STAGE_SOUND = Sound.sound(SoundEvent.UI_TOAST_CHALLENGE_COMPLETE, Sound.Source.MASTER, 0.4f, 1f);
+    private static final Sound BRIDGE_SOUND = Sound.sound(SoundEvent.BLOCK_AMETHYST_BLOCK_CHIME, Sound.Source.MASTER, 1f, 1f);
+    private static final Sound RESCUE_SOUND = Sound.sound(SoundEvent.ITEM_TOTEM_USE, Sound.Source.MASTER, 0.6f, 1f);
+    private static final Sound JOKER_SOUND = Sound.sound(SoundEvent.ENTITY_EXPERIENCE_ORB_PICKUP, Sound.Source.MASTER, 0.8f, 1.2f);
+    private static final Sound RESET_SOUND = Sound.sound(SoundEvent.BLOCK_GLASS_BREAK, Sound.Source.BLOCK, 0.3f, 1f);
+
+    private final Player player;
+    private final Instance world;
+    private final Random random = new Random();
+    private final StageAtmosphere atmosphere;
+
+    // Index des ersten Schritts in course (beim Weiterspielen der gespeicherte Checkpoint)
+    private final int base;
+    private final List<Step> course = new ArrayList<>();
+    private final Map<BlockKey, Integer> courseIndex = new HashMap<>();
+    private int standing;
+    private int combo = 0;
+    private Pos checkpoint;
+    // zuletzt per Brücke überbrückter Bereich: diese Blöcke zählen nicht zur Combo
+    private int bridgeStart = -1;
+    private int bridgeEnd = -1;
+
+    // Sprungfeder: so viele Sprünge noch mit Sprungkraft
+    private int springJumpsLeft = 0;
+
+    // laufende Rettung durch das Totem: der Block, auf den man über die Leiter zurückklettert
+    private Pos rescueSafe;
+
+    /** @param startIndex Fortschritt, ab dem gespielt wird (0 oder ein gespeicherter Checkpoint) */
+    public JumpGenerator(Pos start, int startIndex, Player player, Instance world) {
         this.player = player;
         this.world = world;
-        this.starting = starting;
+        this.base = startIndex;
-        generateStart(starting);
+        this.standing = startIndex;
+        this.checkpoint = start;
+        this.atmosphere = new StageAtmosphere(player, world, BlockPalette.stageAt(startIndex));
+
+        Block startBlock = startIndex == 0 || isMilestone(startIndex) ? Block.DIAMOND_BLOCK : Block.GOLD_BLOCK;
+        this.world.setBlock(start, startBlock);
+        this.addStep(new Step(start, startBlock));
+        this.player.setLevel(startIndex);
+        ScoreTab.update(this.player, startIndex);
+        // wer ganz von vorn beginnt, bekommt ein Totem; beim Weiterspielen gibt es keine Joker
+        if(startIndex > 0) this.player.sendMessage(Component.text("Weiter ab Sprung " + startIndex, NamedTextColor.GOLD));
+        else Jokers.TOTEM.add(this.player);
+
+        // nacheinander animieren, damit jeder Block aus seinem bereits stehenden Vorgänger wächst
+        this.ensureGenerated(startIndex + PREVIEW + 1, BlockTransition.TOTAL_TICKS);
     }
 
-    public void generateNext() {
+    private Step step(int index) {
-        boolean isTenth = this.blocks.size() % 10 == 0;
+        return this.course.get(index - this.base);
-        boolean standingTenth = (this.blocks.size()-this.preview-1) % 10 == 0;
-        boolean isHundredth = this.blocks.size() % 100 == 0;
-
-        float pitch = 1 + (combo * 0.025f);
-        this.player.playSound(Sound.sound(SoundEvent.BLOCK_NOTE_BLOCK_PLING, Sound.Source.MASTER, 0.1f, pitch));
-        this.player.showTitle(Title.title(Component.text(""), Component.text((combo)+"", TextColor.color(255, 69, 0))));
-        this.player.setLevel((this.blocks.size()-this.preview-1));
-
-        Random r = new Random();
-        int index = this.blocks.size();
-        Pos target = blocks.get(blocks.size()-1).add(this.nextOffset(index, r));
-        this.world.setBlock(target, isHundredth ? Block.DIAMOND_BLOCK : isTenth ? Block.GOLD_BLOCK : BlockPalette.getRandom(index, r));
-
-        if(standingTenth) {
-            Pos current = this.blocks.get(this.blocks.size()-this.preview-1);
-            this.checkpoint = current;
-            this.player.playSound(Sound.sound(SoundEvent.ENTITY_PLAYER_LEVELUP, Sound.Source.BLOCK, 0.3f, 1f));
-            this.player.showTitle(Title.title(Component.text(""), Component.text("Checkpoint", TextColor.color(0, 255, 0))));
-            this.player.sendPacket(new ParticlePacket(Particle.CRIT, current, current.add(0.5), 1.5f, 50));
     }
 
-        BlockPalette.Stage reachedStage = BlockPalette.stageStartingAt(this.blocks.size()-this.preview-1);
+    /** Index des nächsten zu erzeugenden Schritts. */
-        if(reachedStage != null && reachedStage.from() > 0) {
+    private int generated() {
-            this.player.playSound(Sound.sound(SoundEvent.UI_TOAST_CHALLENGE_COMPLETE, Sound.Source.MASTER, 0.4f, 1f));
+        return this.base + this.course.size();
-            this.player.showTitle(Title.title(Component.text(reachedStage.name(), TextColor.color(255, 170, 0)), Component.text("")));
     }
-        this.world.setBlock(target.add(0, 1 ,0), Block.LIGHT);
+
-        this.blocks.add(target);
+    private static boolean isCheckpoint(int index) {
-        this.player.sendPacket(new ParticlePacket(Particle.CRIT, target, target.add(0.5), 1, 10));
+        return index % 10 == 0;
-        this.player.sendPacket(new ParticlePacket(Particle.FALLING_NECTAR, target, target.add(0.5),0.3f, 10));
+    }
+
+    private static boolean isMilestone(int index) {
+        return index % 100 == 0;
+    }
+
+    private static double height(Block block) {
+        return block.collisionShape().relativeEnd().y();
+    }
+
+    private Pos landing() {
+        return this.step(this.standing + 1).pos();
+    }
+
+    /** Wird bei jeder Bewegung aufgerufen: erkennt Landungen und behandelt das Runterfallen. */
+    public void onMove(Pos newPosition) {
+        // Block unter den Füßen; -0.5 trifft auch niedrige Blöcke wie den Endportalrahmen
+        Integer index = this.courseIndex.get(BlockKey.of(newPosition.sub(0, 0.5, 0)));
+        if(index != null && index > this.standing) this.advanceTo(index);
+        this.checkFall();
+    }
+
+    private void advanceTo(int index) {
+        int previous = this.standing;
+        this.standing = index;
+        this.player.setLevel(index);
+        ScoreTab.update(this.player, index);
+
+        if(this.springJumpsLeft > 0 && --this.springJumpsLeft == 0) this.player.removeEffect(PotionEffect.JUMP_BOOST);
+
+        if(index < this.bridgeStart || index > this.bridgeEnd) {
             this.combo++;
+            this.player.playSound(Sound.sound(SoundEvent.BLOCK_NOTE_BLOCK_PLING, Sound.Source.MASTER, 0.1f, 1 + this.combo * 0.025f));
+            this.player.showTitle(Title.title(Component.empty(), Component.text(this.combo, COMBO_COLOR)));
+        }
+
+        // auch ein übersprungener Checkpoint zählt: der letzte zwischen altem und neuem Stand
+        int reachedCheckpoint = index / 10 * 10;
+        if(reachedCheckpoint > previous) {
+            this.checkpoint = this.step(reachedCheckpoint).pos();
+            Progress.save(this.player.getUuid(), reachedCheckpoint);
+            this.unloadChunksBehind();
+            this.player.playSound(CHECKPOINT_SOUND);
+            this.player.showTitle(CHECKPOINT_TITLE);
+            this.player.sendPacket(new ParticlePacket(Particle.CRIT, this.checkpoint, this.checkpoint.add(0.5), 1.5f, 50));
+        }
+
+        // neuer Abschnitt: Stimmung wechseln (die Actionbar zeigt der Abschnitt selbst dauerhaft)
+        BlockPalette.Stage stage = BlockPalette.stageAt(index);
+        if(stage != BlockPalette.stageAt(previous)) {
+            this.atmosphere.enter(stage);
+            this.player.playSound(STAGE_SOUND);
+        }
+
+        if(previous < FINALE_AT && index >= FINALE_AT) this.celebrate();
+
+        this.ensureGenerated(index + PREVIEW + 1, 0);
+    }
+
+    /** Durchgespielt (Beginn von „Unendlich“): Feuerwerk rund um den Spieler. */
+    private void celebrate() {
+        this.player.showTitle(FINALE_TITLE);
+
+        // in Blickrichtung: ein paar Raketen nah vor dem Spieler, die meisten in der Ferne links, mittig und rechts
+        Pos origin = this.player.getPosition();
+        Vec forward = origin.direction().withY(0).normalize();
+        Vec right = new Vec(-forward.z(), 0, forward.x());
+        for(int i = 0; i < FIREWORKS_NEAR + FIREWORKS_FAR; i++) {
+            boolean near = i < FIREWORKS_NEAR;
+            double distance = near ? this.random.nextDouble(3, 10) : this.random.nextDouble(20, 45);
+            double side = near ? this.random.nextDouble(-6, 6) : this.random.nextDouble(-25, 25);
+            Pos at = origin.add(forward.mul(distance)).add(right.mul(side)).add(0, near ? 0 : 4, 0);
+            this.world.scheduler().buildTask(() -> Fireworks.launch(this.world, at, this.random))
+                .delay(TaskSchedule.tick(1 + this.random.nextInt(FIREWORKS_SPAN_TICKS)))
+                .schedule();
+        }
     }
 
     /**
-     * Abstand zum nächsten Block. Die Schwierigkeit steigt über die ersten {@link #FULL_DIFFICULTY_AT}
+     * Die Strecke wandert immer in +z. Chunks hinter dem Checkpoint und außerhalb der Sichtweite
-     * Sprünge von leicht (2–3 weit, kaum seitlich/aufwärts) bis zum bisherigen Niveau (3–4 weit,
+     * werden nie wieder gebraucht (Reset und Rettung liegen davor): freigeben, sonst sammeln sich
-     * oft seitlich und aufwärts) und bleibt danach dort.
+     * bei langen Läufen tausende an.
      */
-    private Pos nextOffset(int index, Random r) {
+    private void unloadChunksBehind() {
+        int playerChunk = this.player.getPosition().blockZ() >> 4;
+        int checkpointChunk = this.checkpoint.blockZ() >> 4;
+        int keepFrom = Math.min(checkpointChunk, playerChunk - this.player.effectiveViewDistance()) - 1;
+        for(Chunk chunk : List.copyOf(this.world.getChunks())) {
+            if(chunk.getChunkZ() < keepFrom) this.world.unloadChunk(chunk);
+        }
+    }
+
+    private void ensureGenerated(int upTo, int stepTicks) {
+        int delay = 0;
+        while(this.generated() <= upTo) {
+            this.generateStep(delay, null);
+            delay += stepTicks;
+        }
+    }
+
+    private void addStep(Step step) {
+        this.courseIndex.put(BlockKey.of(step.pos()), this.generated());
+        this.course.add(step);
+    }
+
+    /** Erzeugt den nächsten Streckenblock; {@code afterArrival} läuft, sobald er tatsächlich steht. */
+    private void generateStep(int animationDelayTicks, Runnable afterArrival) {
+        int index = this.generated();
+        Step previous = this.course.getLast();
+        Block block = isMilestone(index) ? Block.DIAMOND_BLOCK : isCheckpoint(index) ? Block.GOLD_BLOCK : BlockPalette.getRandom(index, this.random);
+        Pos target = previous.pos().add(this.nextOffset(index, previous.block(), block));
+        this.addStep(new Step(target, block));
+
+        BlockTransition.animate(this.world, previous.pos(), target, block, animationDelayTicks, () -> {
+            this.world.setBlock(target, block);
+            this.world.setBlock(target.add(0, 1, 0), Block.LIGHT);
+            this.player.sendPacket(new ParticlePacket(Particle.CRIT, target, target.add(0.5), 1, 10));
+            this.player.sendPacket(new ParticlePacket(Particle.FALLING_NECTAR, target, target.add(0.5), 0.3f, 10));
+            if(isMilestone(index) || (isCheckpoint(index) && this.random.nextDouble() < CHECKPOINT_JOKER_CHANCE)) this.dropJoker(target);
+            if(afterArrival != null) afterArrival.run();
+        });
+    }
+
+    /** Auf jedem Diamantblock (und manchem Checkpoint) liegt ein zufälliger Joker zum Einsammeln. */
+    private void dropJoker(Pos target) {
+        ItemEntity item = new ItemEntity(Jokers.random(this.random).item());
+        item.setPickupDelay(Duration.ZERO);
+        item.setInstance(this.world, target.add(0.5, 1, 0.5));
+    }
+
+    /**
+     * Abstand zum nächsten Block. Sprünge sind immer mindestens 3 weit (natürliche Sprint-Weite,
+     * kürzere werden überjumpt). Über die ersten {@link #FULL_DIFFICULTY_AT} Sprünge steigen der
+     * Anteil an 4er-Sprüngen, seitlichen Versätzen und Sprüngen nach oben bis zum bisherigen
+     * Niveau und bleiben danach dort.
+     */
+    private Vec nextOffset(int index, Block from, Block to) {
         double difficulty = Math.min(1.0, (double) index / FULL_DIFFICULTY_AT);
 
-        int dz = 2;
+        int dz = this.random.nextDouble() < 0.1 + 0.4 * difficulty ? 4 : 3;
-        if(r.nextDouble() < 0.5 + 0.5 * difficulty) dz++;
+        int dx = this.random.nextDouble() < 0.1 + 0.57 * difficulty ? (this.random.nextBoolean() ? 1 : -1) : 0;
-        if(r.nextDouble() < 0.5 * difficulty) dz++;
-
-        int dx = r.nextDouble() < 0.1 + 0.57 * difficulty ? (r.nextBoolean() ? 1 : -1) : 0;
 
         double y = this.player.getPosition().y();
-        double roll = r.nextDouble();
+        double roll = this.random.nextDouble();
         int dy = 0;
         if(roll < 0.05 + 0.28 * difficulty && y <= 120) dy = 1;
         else if(roll > 1 - (0.2 + 0.13 * difficulty) && y >= 80) dy = -1;
 
-        // weite Diagonalsprünge nach oben erst gegen Ende
+        // von niedrigen Blöcken (z. B. Endportalrahmen) nie nach oben, und die Oberkante darf
+        // höchstens einen Block höher liegen
+        if(dy == 1 && (height(from) < 1 || height(to) > height(from))) dy = 0;
+
+        // weite Sprünge nach oben erst ab mittlerer, diagonal erst ab hoher Schwierigkeit
+        if(dy == 1 && dz == 4 && difficulty < 0.4) dz = 3;
         if(dy == 1 && dz == 4 && dx != 0 && difficulty < 0.7) dx = 0;
 
-        return new Pos(dx, dy, dz);
+        return new Vec(dx, dy, dz);
     }
 
-    public Pos getNextLanding() {
+    /** Rechtsklick mit einem Joker; true, wenn er verbraucht wurde. Das Totem wirkt nur automatisch. */
-        return this.blocks.get(this.blocks.size()-(preview+1));
+    public boolean useJoker(Jokers joker) {
+        boolean used = switch(joker) {
+            case BRIDGE -> this.useBridge();
+            case FEATHER_FALL -> {
+                this.player.addEffect(new Potion(PotionEffect.SLOW_FALLING, 0, FEATHER_FALL_TICKS));
+                yield true;
+            }
+            case SPRING -> {
+                this.springJumpsLeft = SPRING_JUMPS;
+                this.player.addEffect(new Potion(PotionEffect.JUMP_BOOST, 0, Potion.INFINITE_DURATION));
+                yield true;
+            }
+            case TOTEM -> false;
+        };
+        if(used) this.player.playSound(JOKER_SOUND);
+        return used;
     }
 
-
+    /**
-    public void generateStart(Pos start) {
+     * Joker „Brücke“: verbindet die nächsten {@link #BRIDGE_LENGTH} Blöcke ab der aktuellen Position
-        this.starting = start;
+     * mit einem begehbaren Weg, auch über früher schon geschaffte Stücke (z. B. nach einem Reset).
-        this.checkpoint = start;
+     * Diese Blöcke zählen nicht zur Combo. Ist der Bereich schon überbrückt, passiert nichts.
-        this.blocks.add(this.starting);
-        this.world.setBlock(this.starting, Block.DIAMOND_BLOCK);
-        for(int i = 0; i <= preview; i++) generateNext();
-    }
-
-    public void reset() {
-        /*
-        for(Pos p : this.blocks) {
-            this.world.setBlock(p, Block.AIR);
-        }
-        this.blocks.clear();
      */
+    private boolean useBridge() {
+        int target = this.standing + BRIDGE_LENGTH;
+        if(this.rescueSafe != null || (this.standing >= this.bridgeStart && target <= this.bridgeEnd)) return false;
+        this.bridgeStart = this.standing;
+        this.bridgeEnd = target;
+
+        // bereits stehende Abschnitte sofort, neue Blöcke bekommen ihren Weg bei Ankunft
+        for(int i = this.standing + 1; i < this.generated() && i <= target; i++) {
+            this.buildPath(this.step(i - 1).pos(), this.step(i).pos());
+        }
+        int delay = 0;
+        while(this.generated() <= target) {
+            Pos from = this.course.getLast().pos();
+            int index = this.generated();
+            this.generateStep(delay, () -> this.buildPath(from, this.step(index).pos()));
+            delay += BRIDGE_STEP_TICKS;
+        }
+
+        this.player.playSound(BRIDGE_SOUND);
+        return true;
+    }
+
+    /** Weg auf Höhe des Startblocks; bei seitlichem Versatz zwei Blöcke breit, damit er durchgehend ist. */
+    private void buildPath(Pos from, Pos to) {
+        int minX = Math.min(from.blockX(), to.blockX());
+        int maxX = Math.max(from.blockX(), to.blockX());
+        for(int z = from.blockZ() + 1; z < to.blockZ(); z++) {
+            for(int x = minX; x <= maxX; x++) {
+                Pos pos = new Pos(x, from.blockY(), z);
+                if(this.world.getBlock(pos).compare(Block.AIR)) this.world.setBlock(pos, BRIDGE_BLOCK);
+            }
+        }
+    }
+
+    private void checkFall() {
+        double y = this.player.getPosition().y();
+
+        if(this.rescueSafe != null) {
+            if(y >= this.rescueSafe.y() + 0.9) this.rescueSafe = null;
+            else if(y < this.rescueSafe.blockY() - RESCUE_DEPTH - 3) {
+                this.rescueSafe = null;
+                this.reset();
+            }
+            return;
+        }
+
+        if(y < this.landing().y() - 5 && y < this.checkpoint.y()) {
+            if(Jokers.TOTEM.take(this.player)) this.rescue();
+            else this.reset();
+        }
+    }
+
+    /**
+     * Joker „Rettungstotem“: Plattform unter dem zuletzt erreichten Block, davor eine Stützsäule
+     * mit Leiter, über die man direkt wieder auf den Block klettert. Die Strecke geht immer
+     * mindestens 3 Blöcke nach vorne, die Rettung baut nur dahinter und darunter.
+     */
+    private void rescue() {
+        Pos safe = this.step(this.standing).pos();
+        int x = safe.blockX();
+        int z = safe.blockZ();
+        int floorY = safe.blockY() - RESCUE_DEPTH;
+        this.rescueSafe = safe;
+
+        for(int dx = -1; dx <= 1; dx++) {
+            for(int dz = -3; dz <= -1; dz++) this.placeRescue(new Pos(x + dx, floorY, z + dz), RESCUE_BLOCK);
+        }
+        // Säule direkt hinter dem Block bis auf seine Höhe, Leiter davor (hängt an der Säule)
+        for(int y = floorY + 1; y <= safe.blockY(); y++) {
+            this.placeRescue(new Pos(x, y, z - 1), RESCUE_BLOCK);
+            this.placeRescue(new Pos(x, y, z - 2), Block.LADDER.withProperty("facing", "north"));
+        }
+
+        this.player.setVelocity(Vec.ZERO);
+        this.player.teleport(new Pos(x + 0.5, floorY + 1, z - 1.5, 0, 0));
+        this.player.triggerStatus((byte) 35);
+        this.player.playSound(RESCUE_SOUND);
+    }
+
+    /** Brückenglas darf überschrieben werden, sonst könnte ein früherer Brückenweg die Leiter versperren. */
+    private void placeRescue(Pos pos, Block block) {
+        Block existing = this.world.getBlock(pos);
+        if(existing.compare(Block.AIR) || existing.compare(BRIDGE_BLOCK)) this.world.setBlock(pos, block);
+    }
+
+    /** Beendet alles, was an den Spieler gebunden weiterläuft (Partikel, Musik, Joker-Effekte). */
+    public void close() {
+        this.atmosphere.stop();
+        this.player.removeEffect(PotionEffect.SLOW_FALLING);
+        this.player.removeEffect(PotionEffect.JUMP_BOOST);
+    }
+
+    private void reset() {
         this.player.teleport(this.checkpoint.add(0.5, 1, 0.5));
         this.combo = 0;
-        this.player.showTitle(Title.title(Component.text(""), Component.text("")));
+        this.player.clearTitle();
-
+        this.player.playSound(RESET_SOUND);
-        //generateStart(last);
-        this.player.playSound(Sound.sound(SoundEvent.BLOCK_GLASS_BREAK, Sound.Source.BLOCK, 0.3f, 1f));
-
-    }
-
-    public Pos getCheckpoint() {
-        return checkpoint;
-    }
-
-    public ArrayList<Pos> getBlocks() {
-        return blocks;
-    }
-
-    public int getPreview() {
-        return preview;
     }
 }

src/main/java/eu/mhsl/minecraft/endlessjumper/generator/StageAtmosphere.java

@@ -0,0 +1,103 @@
+package eu.mhsl.minecraft.endlessjumper.generator;
+
+import net.kyori.adventure.sound.Sound;
+import net.kyori.adventure.sound.SoundStop;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import net.minestom.server.coordinate.Vec;
+import net.minestom.server.entity.Player;
+import net.minestom.server.instance.Instance;
+import net.minestom.server.network.packet.server.play.ParticlePacket;
+import net.minestom.server.timer.Task;
+import net.minestom.server.timer.TaskSchedule;
+
+import java.util.function.Supplier;
+
+/**
+ * Stimmung des aktuellen Abschnitts: Tageszeit (fließender Übergang), Musik, Partikel auf der
+ * Strecke voraus und der Abschnittsname dauerhaft in der Actionbar.
+ */
+class StageAtmosphere {
+    private static final int TIME_TRANSITION_TICKS = 100;
+    // die Strecke läuft immer in +z: Partikel vom Spieler bis etwa 10 Sprünge voraus
+    private static final Vec AMBIENT_AHEAD = new Vec(0, 1.5, 14);
+    private static final Vec AMBIENT_SPREAD = new Vec(7, 4, 16);
+    private static final int AMBIENT_EVERY_TICKS = 4;
+    // die Actionbar blendet nach ~3 s aus: jede Sekunde erneuern, nach einem Wechsel 5 s golden
+    private static final int ACTION_BAR_TICKS = 20;
+    private static final int HIGHLIGHT_TICKS = 100;
+    private static final Component ENDLESS_HINT = Component.text("  ·  /reset für einen Neustart", NamedTextColor.DARK_GRAY);
+
+    private final Player player;
+    private final Instance world;
+    private BlockPalette.Stage stage;
+    private Task timeTransition;
+    private final Task ambient;
+    private int ticks = 0;
+    private int highlightUntil = 0;
+
+    StageAtmosphere(Player player, Instance world, BlockPalette.Stage initial) {
+        this.player = player;
+        this.world = world;
+        this.stage = initial;
+        this.world.setTime(initial.time());
+        this.world.refreshTime();
+        this.playMusic();
+        // an den Spieler gebunden, endet also mit ihm
+        this.ambient = player.scheduler().buildTask(this::tick).repeat(TaskSchedule.tick(AMBIENT_EVERY_TICKS)).schedule();
+    }
+
+    void stop() {
+        this.ambient.cancel();
+        if(this.timeTransition != null) this.timeTransition.cancel();
+        this.player.stopSound(SoundStop.source(Sound.Source.MUSIC));
+    }
+
+    void enter(BlockPalette.Stage next) {
+        if(next == this.stage) return;
+        this.stage = next;
+        this.highlightUntil = this.ticks + HIGHLIGHT_TICKS;
+        this.playMusic();
+        this.fadeTimeTo(next.time());
+        this.showStage();
+    }
+
+    private void playMusic() {
+        this.player.stopSound(SoundStop.source(Sound.Source.MUSIC));
+        this.player.playSound(Sound.sound(this.stage.music(), Sound.Source.MUSIC, 1f, 1f));
+    }
+
+    /** Läuft immer vorwärts zur Zielzeit, Tick für Tick, damit Himmel und Licht weich wechseln. */
+    private void fadeTimeTo(long target) {
+        if(this.timeTransition != null) this.timeTransition.cancel();
+        long start = this.world.getTime();
+        long delta = Math.floorMod(target - start, 24000L);
+        if(delta == 0) return;
+
+        this.timeTransition = this.world.scheduler().submitTask(new Supplier<>() {
+            private int tick = 0;
+
+            @Override
+            public TaskSchedule get() {
+                this.tick++;
+                StageAtmosphere.this.world.setTime(start + delta * this.tick / TIME_TRANSITION_TICKS);
+                StageAtmosphere.this.world.refreshTime();
+                return this.tick < TIME_TRANSITION_TICKS ? TaskSchedule.tick(1) : TaskSchedule.stop();
+            }
+        });
+    }
+
+    private void tick() {
+        this.ticks += AMBIENT_EVERY_TICKS;
+        if(this.ticks % ACTION_BAR_TICKS == 0) this.showStage();
+        if(this.stage.ambient() != null) {
+            this.player.sendPacket(new ParticlePacket(this.stage.ambient(), this.player.getPosition().add(AMBIENT_AHEAD), AMBIENT_SPREAD, 0.02f, 8));
+        }
+    }
+
+    private void showStage() {
+        Component text = Component.text(this.stage.name(), this.ticks < this.highlightUntil ? NamedTextColor.GOLD : NamedTextColor.GRAY);
+        if(BlockPalette.isEndless(this.stage)) text = text.append(ENDLESS_HINT);
+        this.player.sendActionBar(text);
+    }
+}