Add destroy method to World and change chunk loading functions

blokk-api/src/main/kotlin/space/blokk/net/event/PlayerInitializationEvent.kt

@@ -12,5 +12,5 @@ import space.blokk.world.VoxelLocation
  */
 class PlayerInitializationEvent(override val target: Session, val settings: Player.Settings) : SessionEvent(), Cancellable {
     override var cancelled = false
-    var compassTarget: VoxelLocation = VoxelLocation(0, 0, 0)
+    var compassTarget: VoxelLocation = VoxelLocation.of(0, 0, 0)
 }

blokk-api/src/main/kotlin/space/blokk/world/Chunk.kt

@@ -79,28 +79,20 @@ abstract class Chunk(
      * Returns whether this chunk contains [voxel].
      */
     // It does not just compare voxel.chunk with this because voxel.chunk may be expensive to create
-    operator fun contains(voxel: Voxel) = contains(voxel.location)
+    operator fun contains(voxel: Voxel) = voxel.world == world && contains(voxel.location)
 
     abstract fun getData(player: Player?): ChunkData
-
     abstract fun getLightData(player: Player?): ChunkLightData
 
     /**
-     * Loads this chunk into memory.
+     * Starts loading this chunk into memory.
      *
-     * If the chunk is already loaded, this function does nothing.
+     * Does nothing if the chunk is already loaded or loading.
      */
-    open suspend fun load() {}
+    open fun startLoading() {}
+    open suspend fun waitUntilLoaded() {}
 
-    val loaded get() = loadState == LoadState.LOADED
+    open val loaded = true
-
-    open val loadState: LoadState = LoadState.LOADED
-
-    enum class LoadState {
-        NOT_LOADED,
-        LOADING,
-        LOADED
-    }
 
     companion object {
         const val LENGTH: Int = 16
@@ -108,4 +100,8 @@ abstract class Chunk(
         const val SECTION_HEIGHT: Int = 16
         const val BLOCKS_IN_A_SECTION = AREA * SECTION_HEIGHT
     }
+
+    interface Unloadable {
+        suspend fun unload()
+    }
 }

blokk-api/src/main/kotlin/space/blokk/world/Voxel.kt

@@ -20,7 +20,10 @@ abstract class Voxel {
     val loaded: Boolean get() = chunk.loaded
 
     /**
-     * Shorthand for [`chunk.load()`][Chunk.load].
+     * Loads [chunk] if it is not yet loaded.
      */
-    suspend fun load() = chunk.load()
+    suspend fun loadAndWait() {
+        chunk.startLoading()
+        chunk.waitUntilLoaded()
+    }
 }

blokk-api/src/main/kotlin/space/blokk/world/VoxelLocation.kt

@@ -46,6 +46,13 @@ data class VoxelLocation(val x: Int, val y: UByte, val z: Int) {
         CoordinatePart.Y -> y.toInt()
         CoordinatePart.Z -> z
     }
+
+    companion object {
+        fun of(x: Int, y: Int, z: Int): VoxelLocation {
+            if (y !in 0..255) throw IllegalArgumentException("y must be in 0..255")
+            return VoxelLocation(x, y.toUByte(), z)
+        }
+    }
 }
 
 

blokk-api/src/main/kotlin/space/blokk/world/World.kt

@@ -84,18 +84,23 @@ abstract class World(val uuid: UUID) {
         radius: Int,
         hollow: Boolean
     ): List<Voxel> {
-        // Implementation example https://git.io/JLysq
+        // Implementation example: https://git.io/JLysq
         TODO()
     }
 
     /**
-     * Spawns an [entity][Entity] in this world.
+     * Spawns [entity][Entity] in this world.
      */
     abstract fun spawnEntity(entity: Entity)
 
-    fun unload() {
+    suspend fun destroy() = withContext(coroutineContext) {
+        // TODO: Move or kick players
         coroutineContext.cancel()
-        // TODO: Unload chunks
+
+        coroutineScope {
+            loadedChunks.values.forEach { launch { (it as? Chunk.Unloadable)?.unload() } }
+        }
+
         threadExecutor.close()
     }
 }

test-plugin/src/main/kotlin/space/blokk/testplugin/TestPlugin.kt

@@ -24,16 +24,16 @@ class TestPlugin: Plugin("Test", "1.0.0") {
         Blokk.dimensionRegistry.register(dimension)
 
         val world = AnvilWorld(dimension, true)
-        world.getVoxelsInCube(VoxelLocation(16, 0, 16), VoxelLocation(-16, 0, -16)).forEach {
+        world.getVoxelsInCube(VoxelLocation.of(16, 0, 16), VoxelLocation.of(-16, 0, -16)).forEach {
             it.block = if (it.location.x % 16 == 0 || it.location.z % 16 == 0) GreenWool() else RedWool()
         }
 
-        world.getVoxel(VoxelLocation(-1, 2, -1)).block = CraftingTable()
+        world.getVoxel(VoxelLocation.of(-1, 2, -1)).block = CraftingTable()
 
         Blokk.eventBus.on<SessionAfterLoginEvent> { event ->
             event.initialWorldAndLocation = WorldAndLocationWithRotation(
                 world,
-                VoxelLocation(0, 2, 0).atTopCenter().withRotation(0f, 0f)
+                VoxelLocation.of(0, 2, 0).atTopCenter().withRotation(0f, 0f)
             )
         }
     }