Merge pull request #22 from 34638a/dev

Patch to stop the java.util.ConcurrentModificationException.

src/main/java/com/jozufozu/flywheel/backend/instancing/InstanceManager.java

@@ -1,9 +1,16 @@
 package com.jozufozu.flywheel.backend.instancing;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+import java.util.function.Consumer;
 
 import javax.annotation.Nullable;
 
@@ -11,6 +18,7 @@ import com.jozufozu.flywheel.backend.Backend;
 import com.jozufozu.flywheel.backend.material.MaterialManager;
 
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.objects.ObjectArraySet;
 import net.minecraft.client.renderer.ActiveRenderInfo;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.vector.Vector3f;
@@ -19,8 +27,8 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 
 	public final MaterialManager<?> materialManager;
 
-	protected final ArrayList<T> queuedAdditions;
+	private final Set<T> queuedAdditions;
-	protected final ConcurrentHashMap.KeySetView<T, Boolean> queuedUpdates;
+	private final Set<T> queuedUpdates;
 
 	protected final Map<T, IInstance> instances;
 	protected final Object2ObjectOpenHashMap<T, ITickableInstance> tickableInstances;
@@ -31,8 +39,8 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 
 	public InstanceManager(MaterialManager<?> materialManager) {
 		this.materialManager = materialManager;
-		this.queuedUpdates = ConcurrentHashMap.newKeySet(64);
+		this.queuedUpdates = new HashSet<>(64);
-		this.queuedAdditions = new ArrayList<>(64);
+		this.queuedAdditions = new HashSet<>(64);
 		this.instances = new HashMap<>();
 
 		this.dynamicInstances = new Object2ObjectOpenHashMap<>();
@@ -49,6 +57,7 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 
 	public void tick(double cameraX, double cameraY, double cameraZ) {
 		tick++;
+		processQueuedUpdates();
 
 		// integer camera pos
 		int cX = (int) cameraX;
@@ -72,12 +81,6 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 				if ((tick % getUpdateDivisor(dX, dY, dZ)) == 0) instance.tick();
 			});
 		}
-
-		queuedUpdates.forEach(te -> {
-			queuedUpdates.remove(te);
-
-			update(te);
-		});
 	}
 
 	public void beginFrame(ActiveRenderInfo info) {
@@ -118,8 +121,10 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 		if (!Backend.getInstance()
 				.canUseInstancing()) return;
 
+		synchronized (queuedAdditions) {
 			queuedAdditions.add(obj);
 		}
+	}
 
 	public void update(T obj) {
 		if (!Backend.getInstance()
@@ -144,9 +149,10 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 	public synchronized void queueUpdate(T obj) {
 		if (!Backend.getInstance()
 				.canUseInstancing()) return;
-
+		synchronized (queuedUpdates) {
 			queuedUpdates.add(obj);
 		}
+	}
 
 	public void onLightUpdate(T obj) {
 		if (!Backend.getInstance()
@@ -176,7 +182,6 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 		tickableInstances.clear();
 	}
 
-	@SuppressWarnings("unchecked")
 	@Nullable
 	protected <I extends T> IInstance getInstance(I obj, boolean create) {
 		if (!Backend.getInstance()
@@ -193,11 +198,30 @@ public abstract class InstanceManager<T> implements MaterialManager.OriginShiftL
 		}
 	}
 
-	protected synchronized void processQueuedAdditions() {
+	protected void processQueuedAdditions() {
-		if (queuedAdditions.size() > 0) {
+		ArrayList<T> queued;
-			queuedAdditions.forEach(this::addInternal);
+
+		synchronized (queuedAdditions) {
+			queued = new ArrayList<>(queuedAdditions);
 			queuedAdditions.clear();
 		}
+
+		if (queued.size() > 0) {
+			queued.forEach(this::addInternal);
+		}
+	}
+
+	protected void processQueuedUpdates() {
+		ArrayList<T> queued;
+
+		synchronized (queuedUpdates) {
+			queued = new ArrayList<>(queuedUpdates);
+			queuedUpdates.clear();
+		}
+
+		if (queued.size() > 0) {
+			queued.forEach(this::update);
+		}
 	}
 
 	protected boolean shouldFrameUpdate(BlockPos worldPos, float lookX, float lookY, float lookZ, int cX, int cY, int cZ) {