Added multiple kinds of instance update (per instance, per chunk, single-threaded)

src/main/java/net/minestom/server/instance/InstanceManager.java

@@ -16,6 +16,7 @@ public class InstanceManager {
     private ExecutorService blocksPool = new MinestomThread(MinecraftServer.THREAD_COUNT_BLOCK_UPDATE, MinecraftServer.THREAD_NAME_BLOCK_UPDATE);
 
     private Set<Instance> instances = Collections.synchronizedSet(new HashSet<>());
+    private UpdateType updateType = UpdateType.PER_INSTANCE;
 
     public InstanceContainer createInstanceContainer(Dimension dimension, StorageFolder storageFolder) {
         InstanceContainer instance = new InstanceContainer(UUID.randomUUID(), dimension, storageFolder);
@@ -50,6 +51,38 @@ public class InstanceManager {
             return;
 
         long time = System.currentTimeMillis();
+
+        switch (updateType) {
+            case PER_INSTANCE:
+                perInstanceUpdate(time);
+                break;
+            case PER_CHUNK:
+                perChunkUpdate(time);
+                break;
+            case SINGLE_THREADED:
+                singleThreadedUpdate(time);
+                break;
+        }
+    }
+
+    public Set<Instance> getInstances() {
+        return Collections.unmodifiableSet(instances);
+    }
+
+    public UpdateType getUpdateType() {
+        return updateType;
+    }
+
+    public void setUpdateType(UpdateType updateType) {
+        this.updateType = updateType;
+    }
+
+    /**
+     * A thread per instance
+     *
+     * @param time the update time
+     */
+    private void perInstanceUpdate(long time) {
         for (Instance instance : instances) {
             if (instance instanceof InstanceContainer) { // SharedInstance should be updated at the same time (verify?)
 
@@ -64,8 +97,48 @@ public class InstanceManager {
         }
     }
 
-    public Set<Instance> getInstances() {
-        return Collections.unmodifiableSet(instances);
+    /**
+     * A thread per chunk + a different one for the instance tick
+     *
+     * @param time the update time
+     */
+    private void perChunkUpdate(long time) {
+        for (Instance instance : instances) {
+            if (instance instanceof InstanceContainer) { // SharedInstance should be updated at the same time (verify?)
+
+                blocksPool.execute(() -> instance.tick(time));
+
+                for (Chunk chunk : instance.getChunks()) {
+                    blocksPool.execute(() -> chunk.updateBlocks(time, instance));
+                }
+
+            }
+        }
+    }
+
+    /**
+     * Update everything on the current thread
+     *
+     * @param time the update time
+     */
+    private void singleThreadedUpdate(long time) {
+        for (Instance instance : instances) {
+            if (instance instanceof InstanceContainer) { // SharedInstance should be updated at the same time (verify?)
+
+                instance.tick(time);
+
+                for (Chunk chunk : instance.getChunks()) {
+                    chunk.updateBlocks(time, instance);
+                }
+
+            }
+        }
+    }
+
+    public enum UpdateType {
+        PER_INSTANCE,
+        PER_CHUNK,
+        SINGLE_THREADED
     }
 
 }