Bug fixes, config file, more commands

- fixed chunk skips skipping not-generated chunks
- changed command structure to /chunkmaster <operation>
- added config options
- updated readme

README.md

@@ -1,17 +1,50 @@
 # chunkmaster
 
-This plugin can be used to pre-generate the region of a world around the spawn chunk. The plugin provides the commands
+This plugin can be used to pre-generate the region of a world around the spawn chunk.
-
-- `/generate [world] [stopAt]` - Pre-generates chunks in the current world until the world border or the stopAt chunk count is reached.
-- `/listgentasks` - Lists all running generation tasks (and their ids)
-- `/removegentask [taskId]` - Removes a generation task (stops it permanently)
-
 The generation automatically pauses when a player joins the server (assuming the server was empty before)
 and resumes when the server is empty again. The generation also auto-resumes after a server
 restart. The plugin tracks the ticks per second and pauses the generation when the tps
 is lower than 2.
 
-## Future Features
+## Commands
+
+All features can be accessed with the command `/chunkmaster` or the aliases `/chm`, `chunkm`, `cmaster`.
+
+- `/chunkmaster generate [world] [chunk count]` Starts the generation until the specified chunk count or the world border is reached.
+- `/chunkmaster list` Lists all running generation tasks
+- `/chunkmaster cancel <Task id>` Cancels the generation task with the specified id (if it is running).
+- `/chunkmaster pause` Pauses all generation tasks until the resume command is executed.
+- `/chunkmaster resume` Resumes all paused generation tasks.
+- `/chunkmaster reload` Reloads the configuration file.
+
+## Config
+
+```yaml
+generation:
+
+  # The period (in ticks) in which a generation step is run.
+  # Higher values mean less performance impact but slower generation.
+  # The value should be a positive integer.
+  period: 2
+
+  # The number of already generated chunks that will be skipped for each step.
+  # Notice that these still have a performance impact because the server needs to check
+  # if the chunk is generated.
+  # Higher values mean faster generation but greater performance impact.
+  # The value should be a positive integer.
+  chunks-skips-per-step: 5
+
+  # The maximum milliseconds per tick the server is allowed to have
+  # during the cunk generation process.
+  # If the mspt is greather than this, the chunk generation task pauses.
+  # The value should be a positive integer greater than 50.  
+  mspt-pause-threshold: 500
 
-- pause generation tasks until restarted by command
+  # If the chunk generation process should pause on player join.
-- configure the tps pause limit
+  # Notice that playing on a server that constantly generates chunks can be
+  # very laggy and can cause it to crash.
+  # You could configure the values above so that the performance impact of the generation
+  # process is minimal.
+  # The value should be a boolean <true/false>
+  pause-on-join: true
+```

src/main/kotlin/net/trivernis/chunkmaster/Chunkmaster.kt

@@ -1,17 +1,13 @@
 package net.trivernis.chunkmaster
 
-import net.trivernis.chunkmaster.commands.CommandGenerate
+import net.trivernis.chunkmaster.commands.*
-import net.trivernis.chunkmaster.commands.CommandListGenTasks
-import net.trivernis.chunkmaster.commands.CommandRemoveGenTask
 import net.trivernis.chunkmaster.lib.GenerationManager
-import net.trivernis.chunkmaster.lib.Spiral
 import net.trivernis.chunkmaster.lib.SqlUpdateManager
 import org.bukkit.plugin.java.JavaPlugin
 import org.bukkit.scheduler.BukkitTask
 import java.lang.Exception
 import java.sql.Connection
 import java.sql.DriverManager
-import kotlin.math.log
 
 class Chunkmaster: JavaPlugin() {
     lateinit var sqliteConnection: Connection
@@ -19,7 +15,7 @@ class Chunkmaster: JavaPlugin() {
     lateinit var generationManager: GenerationManager
     private lateinit var tpsTask: BukkitTask
     var mspt = 50L      // keep track of the milliseconds per tick
-        get() = field
+        private set
 
     /**
      * On enable of the plugin
@@ -29,10 +25,12 @@ class Chunkmaster: JavaPlugin() {
         initDatabase()
         generationManager = GenerationManager(this, server)
         generationManager.init()
-        getCommand("generate")?.setExecutor(CommandGenerate(this))
+
-        getCommand("listgentasks")?.setExecutor(CommandListGenTasks(this))
+        getCommand("chunkmaster")?.setExecutor(CommandChunkmaster(this, server))
-        getCommand("removegentask")?.setExecutor(CommandRemoveGenTask(this))
+        getCommand("chunkmaster")?.aliases = mutableListOf("chm", "chunkm", "cmaster")
+
         server.pluginManager.registerEvents(ChunkmasterEvents(this, server), this)
+
         tpsTask = server.scheduler.runTaskTimer(this, Runnable {
             val start = System.currentTimeMillis()
             server.scheduler.runTaskLater(this, Runnable {
@@ -55,7 +53,12 @@ class Chunkmaster: JavaPlugin() {
      */
     private fun configure() {
         dataFolder.mkdir()
+        config.addDefault("generation.period", 2L)
+        config.addDefault("generation.chunks-skips-per-step", 4)
+        config.addDefault("generation.mspt-pause-threshold", 500L)
+        config.addDefault("generation.pause-on-join", true)
         config.options().copyDefaults(true)
+        saveConfig()
     }
 
     /**

src/main/kotlin/net/trivernis/chunkmaster/ChunkmasterEvents.kt

@@ -8,24 +8,32 @@ import org.bukkit.event.player.PlayerQuitEvent
 
 class ChunkmasterEvents(private val chunkmaster: Chunkmaster, private val server: Server): Listener {
 
+    private val pauseOnJoin = chunkmaster.config.getBoolean("generation.pause-on-join")
+
     /**
      * Autostart generation tasks
      */
     @EventHandler fun onPlayerQuit(event: PlayerQuitEvent) {
+        if (pauseOnJoin) {
             if (server.onlinePlayers.size == 1 && server.onlinePlayers.contains(event.player) ||
                 server.onlinePlayers.isEmpty()) {
+                if (!chunkmaster.generationManager.paused) {
                     chunkmaster.generationManager.startAll()
                     chunkmaster.logger.info("Server is empty. Starting chunk generation tasks.")
                 }
             }
+        }
+    }
 
     /**
      * Autostop generation tasks
      */
     @EventHandler fun onPlayerJoin(event: PlayerJoinEvent) {
+        if (pauseOnJoin) {
             if (server.onlinePlayers.size == 1 || server.onlinePlayers.isEmpty()) {
                 chunkmaster.generationManager.stopAll()
                 chunkmaster.logger.info("Stopping generation tasks because of player join.")
             }
         }
     }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CmdCancel.kt

@@ -0,0 +1,28 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.command.CommandSender
+
+class CmdCancel(private val chunkmaster: Chunkmaster): Subcommand {
+    override val name = "cancel"
+
+    override fun execute(sender: CommandSender, args: List<String>): Boolean {
+        return if (args.isNotEmpty() && args[0].toIntOrNull() != null) {
+            if (chunkmaster.generationManager.removeTask(args[0].toInt())) {
+                sender.sendMessage("Task ${args[0]} canceled.")
+                true
+            } else {
+                sender.spigot().sendMessage(*ComponentBuilder("Task ${args[0]} not found!")
+                    .color(ChatColor.RED).create())
+                false
+            }
+        } else {
+            sender.spigot().sendMessage(*ComponentBuilder("You need to provide a task id to cancel.")
+                .color(ChatColor.RED).create())
+            false
+        }
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CmdGenerate.kt

@@ -0,0 +1,55 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.command.CommandSender
+import org.bukkit.entity.Player
+
+class CmdGenerate(private val chunkmaster: Chunkmaster): Subcommand {
+    override val name = "generate"
+
+    override fun execute(sender: CommandSender, args: List<String>): Boolean {
+        var worldName = ""
+        var stopAfter = -1
+        if (sender is Player) {
+            if (args.isNotEmpty()) {
+                if (args[0].toIntOrNull() != null) {
+                    stopAfter = args[0].toInt()
+                } else {
+                    worldName = args[0]
+                }
+                if (args.size > 1 && args[1].toIntOrNull() != null) {
+                    stopAfter = args[1].toInt()
+                }
+            } else {
+                worldName = sender.world.name
+            }
+        } else {
+            if (args.isNotEmpty()) {
+                worldName = args[0]
+                if (args.size > 1 && args[1].toIntOrNull() != null) {
+                    stopAfter = args[1].toInt()
+                }
+            } else {
+                sender.spigot().sendMessage(
+                    *ComponentBuilder("You need to provide a world name").color(ChatColor.RED).create())
+                return false
+            }
+        }
+        val world = chunkmaster.server.getWorld(worldName)
+        return if (world != null) {
+            chunkmaster.generationManager.addTask(world, stopAfter)
+            sender.spigot().sendMessage(*ComponentBuilder("Generation task for world ").color(ChatColor.BLUE)
+                .append(worldName).color(ChatColor.GREEN).append(" until ").color(ChatColor.BLUE)
+                .append(if (stopAfter > 0) "$stopAfter chunks" else "WorldBorder").color(ChatColor.GREEN)
+                .append(" successfully created").color(ChatColor.BLUE).create())
+            true
+        } else {
+            sender.spigot().sendMessage(*ComponentBuilder("World ").color(ChatColor.RED)
+                .append(worldName).color(ChatColor.GREEN).append(" not found!").color(ChatColor.RED).create())
+            false
+        }
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CmdList.kt

@@ -0,0 +1,27 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.command.CommandSender
+
+class CmdList(private val chunkmaster: Chunkmaster): Subcommand {
+    override val name = "list"
+
+    override fun execute(sender: CommandSender, args: List<String>): Boolean {
+        val runningTasks = chunkmaster.generationManager.tasks
+        if (runningTasks.isEmpty()) {
+            sender.spigot().sendMessage(*ComponentBuilder("There are no running generation tasks.")
+                .color(ChatColor.BLUE).create())
+        } else {
+            val response = ComponentBuilder("Currently running generation tasks:").color(ChatColor.WHITE)
+            for (task in runningTasks) {
+                response.append("\n - #${task.id}: ${task.generationTask.world.name}, Progress ${task.generationTask.count}")
+                    .color(ChatColor.BLUE)
+            }
+            sender.spigot().sendMessage(*response.create())
+        }
+        return true
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CmdPause.kt

@@ -0,0 +1,27 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.command.CommandSender
+
+class CmdPause(private val chunkmaster: Chunkmaster) : Subcommand {
+    override val name: String = "pause"
+
+    override fun execute(sender: CommandSender, args: List<String>): Boolean {
+        return if (!chunkmaster.generationManager.paused) {
+            chunkmaster.generationManager.pauseAll()
+            sender.spigot().sendMessage(
+                *ComponentBuilder("Paused all generation tasks.")
+                    .color(ChatColor.BLUE).create()
+            )
+            true
+        } else {
+            sender.spigot().sendMessage(
+                *ComponentBuilder("The generation process is already paused.").color(ChatColor.RED).create()
+            )
+            false
+        }
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CmdResume.kt

@@ -0,0 +1,24 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.command.CommandSender
+
+class CmdResume(private val chunkmaster: Chunkmaster): Subcommand {
+    override val name = "resume"
+
+    override fun execute(sender: CommandSender, args: List<String>): Boolean {
+        return if (chunkmaster.generationManager.paused) {
+            chunkmaster.generationManager.resumeAll()
+            sender.spigot().sendMessage(
+                *ComponentBuilder("Resumed all generation tasks.").color(ChatColor.BLUE).create())
+            true
+        } else {
+            sender.spigot().sendMessage(
+                *ComponentBuilder("There are no paused generation tasks.").color(ChatColor.RED).create())
+            false
+        }
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CommandChunkmaster.kt

@@ -0,0 +1,76 @@
+package net.trivernis.chunkmaster.commands
+
+import net.md_5.bungee.api.ChatColor
+import net.md_5.bungee.api.chat.ComponentBuilder
+import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.Subcommand
+import org.bukkit.Server
+import org.bukkit.command.Command
+import org.bukkit.command.CommandExecutor
+import org.bukkit.command.CommandSender
+import org.bukkit.command.TabCompleter
+
+class CommandChunkmaster(private val chunkmaster: Chunkmaster, private val server: Server): CommandExecutor,
+    TabCompleter {
+    private val commands = HashMap<String, Subcommand>()
+
+    init {
+        registerCommands()
+    }
+
+    /**
+     * Tab complete for commands
+     */
+    override fun onTabComplete(sender: CommandSender, command: Command, alias: String, args: Array<out String>):
+            MutableList<String> {
+        return commands.keys.filter { it.indexOf(args[0]) == 0 }.toMutableList()
+    }
+
+    /**
+     * /chunkmaster command to handle all commands
+     */
+    override fun onCommand(sender: CommandSender, command: Command, label: String, args: Array<out String>): Boolean {
+        if (args.isNotEmpty()) {
+            when (args[0]) {
+                "reload" -> {
+                    chunkmaster.reloadConfig()
+                    sender.sendMessage("Configuration file reloaded.")
+                }
+                else -> {
+                    if (sender.hasPermission("chunkmaster.${args[0]}")) {
+                        return if (commands.containsKey(args[0])) {
+                            commands[args[0]]!!.execute(sender, args.slice(1 until args.size))
+                        } else {
+                            sender.spigot().sendMessage(*ComponentBuilder("Subcommand ").color(ChatColor.RED)
+                                .append(args[0]).color(ChatColor.GREEN).append(" not found").color(ChatColor.RED).create())
+                            false
+                        }
+                    } else {
+                        sender.spigot().sendMessage(*ComponentBuilder("You do not have permission!")
+                            .color(ChatColor.RED).create())
+                    }
+                }
+            }
+            return true
+        } else {
+            return false
+        }
+    }
+
+    fun registerCommands() {
+        val cmdGenerate = CmdGenerate(chunkmaster)
+        commands[cmdGenerate.name] = cmdGenerate
+
+        val cmdPause = CmdPause(chunkmaster)
+        commands[cmdPause.name] = cmdPause
+
+        val cmdResume = CmdResume(chunkmaster)
+        commands[cmdResume.name] = cmdResume
+
+        val cmdCancel = CmdCancel(chunkmaster)
+        commands[cmdCancel.name] = cmdCancel
+
+        val cmdList = CmdList(chunkmaster)
+        commands[cmdList.name] = cmdList
+    }
+}

src/main/kotlin/net/trivernis/chunkmaster/commands/CommandGenerate.kt

@@ -1,54 +0,0 @@
-package net.trivernis.chunkmaster.commands
-
-import net.trivernis.chunkmaster.Chunkmaster
-import org.bukkit.command.Command
-import org.bukkit.command.CommandExecutor
-import org.bukkit.command.CommandSender
-import org.bukkit.entity.Player
-
-class CommandGenerate(private val chunkmaster: Chunkmaster): CommandExecutor {
-    /**
-     * Start world generation task on commmand
-     */
-    override fun onCommand(sender: CommandSender, command: Command, label: String, args: Array<out String>): Boolean {
-        if (sender is Player) {
-            return if (command.testPermission(sender)) {
-                var stopAfter = -1
-
-                if (args.isNotEmpty() && args[0].toIntOrNull() != null) {
-                    stopAfter = args[0].toInt()
-                }
-                chunkmaster.generationManager.addTask(sender.world, stopAfter)
-                sender.sendMessage("Added generation task for world \"${sender.world.name}\"" +
-                        "Stopping after $stopAfter chunks (-1 for world border).")
-                true
-            } else {
-                sender.sendMessage("You do not have permission.")
-                true
-            }
-        } else {
-            return if (args.size >= 1) {
-                val world = sender.server.getWorld(args[0])
-                if (world != null) {
-                    var stopAfter = -1
-
-                    if (args.size >=2 && args[1].toIntOrNull() != null) {
-                        stopAfter = args[1].toInt()
-                    }
-                    chunkmaster.generationManager.addTask(world, stopAfter)
-
-                    sender.sendMessage("Added generation task for world \"${world.name}\"" +
-                            "Stopping after $stopAfter chunks (-1 for world border).")
-                    true
-                } else {
-                    sender.sendMessage("World \"${args[0]}\" not found")
-                    false
-                }
-            } else {
-                sender.sendMessage("You need to specify a world")
-                false
-            }
-        }
-    }
-
-}

src/main/kotlin/net/trivernis/chunkmaster/commands/CommandListGenTasks.kt

@@ -1,24 +0,0 @@
-package net.trivernis.chunkmaster.commands
-
-import net.md_5.bungee.api.ChatColor
-import net.md_5.bungee.api.chat.ComponentBuilder
-import net.trivernis.chunkmaster.Chunkmaster
-import org.bukkit.command.Command
-import org.bukkit.command.CommandExecutor
-import org.bukkit.command.CommandSender
-
-class CommandListGenTasks(private val chunkmaster: Chunkmaster): CommandExecutor {
-    /**
-     * Responds with a list of running generation tasks.
-     */
-    override fun onCommand(sender: CommandSender, command: Command, label: String, args: Array<out String>): Boolean {
-        val runningTasks = chunkmaster.generationManager.tasks
-        val response = ComponentBuilder("Currently running generation tasks").color(ChatColor.BLUE)
-        for (task in runningTasks) {
-            response.append("\n - #${task.id}: ${task.generationTask.world.name}, Progress ${task.generationTask.count}")
-        }
-        response.color(ChatColor.GREEN)
-        sender.spigot().sendMessage(*response.create())
-        return true
-    }
-}

src/main/kotlin/net/trivernis/chunkmaster/commands/CommandRemoveGenTask.kt

@@ -1,22 +0,0 @@
-package net.trivernis.chunkmaster.commands
-
-import net.trivernis.chunkmaster.Chunkmaster
-import org.bukkit.command.Command
-import org.bukkit.command.CommandExecutor
-import org.bukkit.command.CommandSender
-
-class CommandRemoveGenTask(private val chunkmaster: Chunkmaster): CommandExecutor {
-    /**
-     * Stops the specified generation task and removes it from the autostart.
-     */
-    override fun onCommand(sender: CommandSender, command: Command, label: String, args: Array<out String>): Boolean {
-        return if (command.testPermission(sender) && args.size == 1) {
-            chunkmaster.generationManager.removeTask(args[0].toInt())
-            sender.sendMessage("Task ${args[1].toInt()} canceled.")
-            true
-        } else {
-            sender.sendMessage("Invalid argument.")
-            false
-        }
-    }
-}

src/main/kotlin/net/trivernis/chunkmaster/lib/GenerationManager.kt

@@ -12,14 +12,15 @@ import java.lang.NullPointerException
 class GenerationManager(private val chunkmaster: Chunkmaster, private val server: Server) {
 
     val tasks: HashSet<TaskEntry> = HashSet()
+    var paused = false
+        private set
 
     /**
      * Adds a generation task
      */
     fun addTask(world: World, stopAfter: Int = -1): Int {
         val centerChunk = world.getChunkAt(world.spawnLocation)
-        val generationTask = GenerationTask(chunkmaster, world, centerChunk, centerChunk)
+        val generationTask = GenerationTask(chunkmaster, world, centerChunk, centerChunk, stopAfter)
-        val task = server.scheduler.runTaskTimer(chunkmaster, generationTask, 10, 2)
         val insertStatement = chunkmaster.sqliteConnection.prepareStatement("""
             INSERT INTO generation_tasks (center_x, center_z, last_x, last_z, world, stop_after)
             values (?, ?, ?, ?, ?, ?)
@@ -31,6 +32,7 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
         insertStatement.setString(5, world.name)
         insertStatement.setInt(6, stopAfter)
         insertStatement.execute()
+
         val getIdStatement = chunkmaster.sqliteConnection.prepareStatement("""
             SELECT id FROM generation_tasks ORDER BY id DESC LIMIT 1
         """.trimIndent())
@@ -38,9 +40,16 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
         val result = getIdStatement.resultSet
         result.next()
         val id: Int = result.getInt("id")
-        tasks.add(TaskEntry(id, task, generationTask))
+
         insertStatement.close()
         getIdStatement.close()
+
+        if (!paused) {
+            val task = server.scheduler.runTaskTimer(chunkmaster, generationTask, 10,
+                chunkmaster.config.getLong("generation.period"))
+            tasks.add(TaskEntry(id, task, generationTask))
+        }
+
         return id
     }
 
@@ -48,30 +57,35 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
      * Resumes a generation task
      */
     private fun resumeTask(world: World, center: Chunk, last: Chunk, id: Int, stopAfter: Int = -1) {
+        if (!paused) {
             chunkmaster.logger.info("Resuming chunk generation task for world \"${world.name}\"")
             val generationTask = GenerationTask(chunkmaster, world, center, last, stopAfter)
-        val task = server.scheduler.runTaskTimer(chunkmaster, generationTask, 10, 2)
+            val task = server.scheduler.runTaskTimer(chunkmaster, generationTask, 10,
+                chunkmaster.config.getLong("generation.period"))
             tasks.add(TaskEntry(id, task, generationTask))
         }
+    }
 
     /**
      * Stops a running generation task.
      */
-    fun removeTask(id: Int) {
+    fun removeTask(id: Int): Boolean {
         val taskEntry = this.tasks.find {it.id == id}
         if (taskEntry != null) {
             taskEntry.generationTask.cancel()
             taskEntry.task.cancel()
+            val deleteTask = chunkmaster.sqliteConnection.prepareStatement("""
+                DELETE FROM generation_tasks WHERE id = ?;
+            """.trimIndent())
+            deleteTask.setInt(1, taskEntry.id)
+            deleteTask.execute()
+            deleteTask.close()
             if (taskEntry.task.isCancelled) {
                 tasks.remove(taskEntry)
             }
-            val setAutostart = chunkmaster.sqliteConnection.prepareStatement("""
+            return true
-                DELETE FROM generation_tasks WHERE id = ?
-            """.trimIndent())
-            setAutostart.setInt(1, id)
-            setAutostart.execute()
-            setAutostart.close()
         }
+        return false
     }
 
     /**
@@ -80,6 +94,9 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
      */
     fun init() {
         chunkmaster.logger.info("Creating task to load chunk generation Tasks later...")
+        server.scheduler.runTaskTimer(chunkmaster, Runnable {
+            saveProgress()      // save progress every 30 seconds
+        }, 600, 600)
         server.scheduler.runTaskLater(chunkmaster, Runnable {
             if (server.onlinePlayers.isEmpty()) {
                 startAll()     // run startAll after 10 seconds if empty
@@ -92,14 +109,16 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
      */
     fun stopAll() {
         saveProgress()
+        val removalSet = HashSet<TaskEntry>()
         for (task in tasks) {
             task.generationTask.cancel()
             task.task.cancel()
             if (task.task.isCancelled) {
-                tasks.remove(task)
+                removalSet.add(task)
             }
             chunkmaster.logger.info("Canceled task #${task.id}")
         }
+        tasks.removeAll(removalSet)
     }
 
     /**
@@ -127,12 +146,25 @@ class GenerationManager(private val chunkmaster: Chunkmaster, private val server
             }
         }
         savedTasksStatement.close()
-        server.scheduler.runTaskTimer(chunkmaster, Runnable {
-            saveProgress()      // save progress every 30 seconds
-        }, 600, 600)
         chunkmaster.logger.info("${tasks.size} saved tasks loaded.")
     }
 
+    /**
+     * Pauses all tasks
+     */
+    fun pauseAll() {
+        paused = true
+        stopAll()
+    }
+
+    /**
+     * Resumes all tasks
+     */
+    fun resumeAll() {
+        paused = false
+        startAll()
+    }
+
     /**
      * Saves the task progress
      */

src/main/kotlin/net/trivernis/chunkmaster/lib/GenerationTask.kt

@@ -8,9 +8,11 @@ import org.bukkit.scheduler.BukkitTask
 
 class GenerationTask(private val plugin: Chunkmaster, val world: World,
                      private val centerChunk: Chunk, private val startChunk: Chunk,
-                     val stopAfter: Int = -1): Runnable {
+                     private val stopAfter: Int = -1): Runnable {
     private val spiral: Spiral = Spiral(Pair(centerChunk.x, centerChunk.z), Pair(startChunk.x, startChunk.z))
     private val loadedChunks: HashSet<Chunk> = HashSet()
+    private val chunkSkips = plugin.config.getInt("generation.chunks-skips-per-step")
+    private val msptThreshold = plugin.config.getLong("generation.mspt-pause-threshold")
 
     var count = 0
         private set
@@ -25,7 +27,7 @@ class GenerationTask(private val plugin: Chunkmaster, val world: World,
      * After 10 chunks have been generated, they will all be unloaded and saved.
      */
     override fun run() {
-        if (plugin.mspt < 500L) {    // pause when tps < 2
+        if (plugin.mspt < msptThreshold) {    // pause when tps < 2
             if (loadedChunks.size > 10) {
                 for (chunk in loadedChunks) {
                     if (chunk.isLoaded) {
@@ -33,13 +35,21 @@ class GenerationTask(private val plugin: Chunkmaster, val world: World,
                     }
                 }
             } else {
-                val nextChunkCoords = spiral.next()
+                if (!world.worldBorder.isInside(lastChunk.getBlock(8, 0, 8).location) || (stopAfter in 1..count)) {
-                val chunk = world.getChunkAt(nextChunkCoords.first, nextChunkCoords.second)
-
-                if (!world.worldBorder.isInside(chunk.getBlock(8, 0, 8).location) || (stopAfter in 1..count)) {
                     endReached = true
                     return
                 }
+                var nextChunkCoords = spiral.next()
+                var chunk = world.getChunkAt(nextChunkCoords.first, nextChunkCoords.second)
+
+                for (i in 1 until chunkSkips) {
+                    if (world.isChunkGenerated(chunk.x, chunk.z)) {
+                        nextChunkCoords = spiral.next()     // if the chunk is generated skip 10 chunks per step
+                        chunk = world.getChunkAt(nextChunkCoords.first, nextChunkCoords.second)
+                    } else {
+                        break
+                    }
+                }
 
                 if (!world.isChunkGenerated(chunk.x, chunk.z)) {
                     chunk.load(true)

src/main/kotlin/net/trivernis/chunkmaster/lib/Spiral.kt

@@ -3,8 +3,8 @@ package net.trivernis.chunkmaster.lib
 import kotlin.math.abs
 
 class Spiral(private val center: Pair<Int, Int>, start: Pair<Int, Int>) {
-    var currentPos = start
+    private var currentPos = start
-    var direction = 0
+    private var direction = 0
     var count = 0
 
     /**

src/main/kotlin/net/trivernis/chunkmaster/lib/Subcommand.kt

@@ -0,0 +1,8 @@
+package net.trivernis.chunkmaster.lib
+
+import org.bukkit.command.CommandSender
+
+interface Subcommand {
+    val name: String
+    fun execute(sender: CommandSender, args: List<String>): Boolean
+}

src/main/resources/plugin.yml

@@ -6,31 +6,35 @@ author: Trivernis
 website: trivernis.net
 api-version: '1.14'
 commands:
-  generate:
+  chunkmaster:
-    description: >
+    description: Main command
-      Generates chunks starting from the world spawnpoint.
+    permission: chunkmaster.chunkmaster
-      StopAfter indicates the number of chunks to generate
+    usage: /chunkmaster <generate|list|pause|resume|cancel|reload>
-      (-1 meaning to stop at the world border). If a player
+    aliases:
-      executes the command, the world argument will be ignored.
+      - chm
-    permission: chumkmaster.generate
+      - chunkm
-    usage: /generate [world] [stopAfter]
+      - cmaster
-  listgentasks:
-    description: Lists all generation tasks
-    permission: chunkmaster.listgentasks
-    usage: /listgentasks
-  removegentask:
-    description: Removes the generation task with the specified id
-    permission: chunkmaster.removegentask
-    usage: /removegentask {task-id}
 permissions:
   cunkmaster.generate:
-    description: Allows generate command.
+    description: Allows the generate subcommand.
     default: op
-  chunkmaster.listgentasks:
+  chunkmaster.list:
-    description: Allows the listgentask command.
+    description: Allows the list subcommand.
     default: op
-  chunkmaster.removegentask:
+  chunkmaster.cancel:
-    description: Allows the removegentask command.
+    description: Allows the remove subcommand.
+    default: op
+  chunkmaster.pause:
+    description: Allows the pause subcommand.
+    default: op
+  chunkmaster.resume:
+    description: Allows the resume subcommand.
+    default: op
+  chunkmaster.reload:
+    description: Allows the reload subcommand.
+    default: op
+  chunkmaster.chunkmaster:
+    description: Allows Chunkmaster commands.
     default: op
   chunkmaster.*:
     description: Wildcard permission
@@ -39,3 +43,6 @@ permissions:
       - chunkmaster.generate
       - chunkmaster.listgentasks
       - chunkmaster.removegentask
+      - chunkmaster.pausegentasks
+      - chunkmaster.resumegentasks
+      - chunkmaster.chunkmaster