perf(resource-packs): cache converted packs by content

build.gradle

@@ -88,6 +88,8 @@ dependencies {
         exclude group: "com.viaversion.mcstructs", module: "snbt"
         exclude group: "com.viaversion.mcstructs", module: "converter"
     }
+    api "org.apache.commons:commons-compress:1.28.0"
+    implementation "commons-io:commons-io:2.20.0"
     api "com.vdurmont:semver4j:3.1.0"
     api "com.mojang:brigadier:1.3.10"
     api "at.yawk.lz4:lz4-java:1.12.0"
@@ -101,6 +103,16 @@ dependencies {
     toolImplementation "org.jsoup:jsoup:1.23.2"
     toolImplementation "org.ow2.asm:asm-tree:9.11"
     toolImplementation "net.lenni0451.commons:asm:1.9.2"
+
+    testImplementation "com.viaversion:viaversion-common:5.12.0"
+    testImplementation "com.google.guava:guava:33.7.1-jre"
+    testImplementation "io.netty:netty-handler:4.2.18.Final"
+    testImplementation "org.junit.jupiter:junit-jupiter:6.1.3"
+    testRuntimeOnly "org.junit.platform:junit-platform-launcher:6.1.3"
+}
+
+test {
+    useJUnitPlatform()
 }
 
 def registerToolTask(String name, String toolMainClass, String toolDescription) {

src/main/java/net/raphimc/viabedrock/api/model/entity/CustomEntity.java

@@ -179,7 +179,7 @@ private void spawn() {
             final StructuredItem item = new StructuredItem(BedrockProtocol.MAPPINGS.getJavaItems().get("minecraft:paper"), 1, data);
             javaEntityData.add(new EntityData(partEntity.getJavaEntityDataIndex(EntityDataFields.ITEM_STACK), VersionedTypes.V26_3.entityDataTypes.itemType, item));
 
-            final float scale = (float) resourcePackStorage.getConverterData().get("ce_" + converterKey + "_scale");
+            final float scale = ((Number) resourcePackStorage.getConverterData().get("ce_" + converterKey + "_scale")).floatValue();
             javaEntityData.add(new EntityData(partEntity.getJavaEntityDataIndex(EntityDataFields.SCALE), VersionedTypes.V26_3.entityDataTypes.vector3FType, new Vector3f(scale, scale, scale)));
             javaEntityData.add(new EntityData(partEntity.getJavaEntityDataIndex(EntityDataFields.TRANSLATION), VersionedTypes.V26_3.entityDataTypes.vector3FType, new Vector3f(0F, scale * 0.5F, 0F)));
 

src/main/java/net/raphimc/viabedrock/api/resourcepack/ResourcePackExecutor.java

@@ -0,0 +1,69 @@
+/*
+ * This file is part of ViaBedrock - https://github.com/RaphiMC/ViaBedrock
+ * Copyright (C) 2026 RK_01/RaphiMC and contributors
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+package net.raphimc.viabedrock.api.resourcepack;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Supplier;
+
+/** Bounded background work that never falls back to the connection's event loop. */
+public final class ResourcePackExecutor {
+
+    private final ThreadPoolExecutor executor;
+    private final Set<CompletableFuture<?>> tasks = new HashSet<>();
+
+    public ResourcePackExecutor(final int workers, final int queuedTasks, final String threadName) {
+        final int threads = Math.max(1, Math.min(workers, Runtime.getRuntime().availableProcessors()));
+        this.executor = new ThreadPoolExecutor(threads, threads, 0, TimeUnit.MILLISECONDS, new ArrayBlockingQueue<>(queuedTasks), task -> {
+            final Thread thread = new Thread(task, threadName);
+            thread.setDaemon(true);
+            return thread;
+        }, new ThreadPoolExecutor.AbortPolicy());
+    }
+
+    public synchronized <T> CompletableFuture<T> submit(final Supplier<T> work) {
+        final CompletableFuture<T> result = new CompletableFuture<>();
+        this.tasks.add(result);
+        result.whenComplete((value, error) -> {
+            synchronized (this) {
+                this.tasks.remove(result);
+            }
+        });
+        try {
+            this.executor.execute(() -> {
+                if (result.isDone()) {
+                    return;
+                }
+                try {
+                    result.complete(work.get());
+                } catch (final Throwable error) {
+                    result.completeExceptionally(error);
+                }
+            });
+        } catch (final RejectedExecutionException error) {
+            result.completeExceptionally(error);
+        }
+        return result;
+    }
+
+    public void stop() {
+        final Set<CompletableFuture<?>> waiting;
+        synchronized (this) {
+            this.executor.shutdownNow();
+            waiting = Set.copyOf(this.tasks);
+        }
+        for (final CompletableFuture<?> task : waiting) {
+            task.completeExceptionally(new CancellationException("Resource pack executor stopped"));
+        }
+    }
+
+}

src/main/java/net/raphimc/viabedrock/api/resourcepack/content/Content.java

@@ -21,22 +21,25 @@
 import com.viaversion.viaversion.util.GsonUtil;
 import net.raphimc.viabedrock.api.util.JsonUtil;
 
+import org.apache.commons.io.output.UnsynchronizedByteArrayOutputStream;
+
 import javax.imageio.ImageIO;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Collectors;
-import java.util.zip.Deflater;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipOutputStream;
 
 public abstract class Content {
 
-    private final Map<String, Map<String, String>> langCache = new HashMap<>();
+    private final Set<String> storedZipEntries = new HashSet<>();
+
+    private final Map<String, Map<String, String>> langCache = new ConcurrentHashMap<>();
 
     public abstract List<String> getFilesShallow(final String path, final String extension);
 
@@ -59,7 +62,24 @@ public String getFullPath(final String shortNamePath, final String... extensions
 
     public abstract byte[] get(final String path);
 
-    public abstract boolean put(final String path, final byte[] data);
+    public final boolean put(final String path, final byte[] data) {
+        final boolean replaced = this.putBytes(path, data);
+        this.storedZipEntries.remove(path);
+        return replaced;
+    }
+
+    /** Stores an already compressed payload without another deflation pass when exporting the ZIP. */
+    public final boolean putStored(final String path, final byte[] data) {
+        final boolean replaced = this.putBytes(path, data);
+        this.storedZipEntries.add(path);
+        return replaced;
+    }
+
+    public final boolean isStored(final String path) {
+        return this.storedZipEntries.contains(path);
+    }
+
+    protected abstract boolean putBytes(final String path, final byte[] data);
 
     public String getString(final String path) {
         final byte[] bytes = this.get(path);
@@ -157,22 +177,22 @@ public void putAll(final Content content) {
     }
 
     public void copyFrom(final Content content, final String sourcePath, final String targetPath) {
-        this.put(targetPath, content.get(sourcePath));
+        if (content.isStored(sourcePath)) {
+            this.putStored(targetPath, content.get(sourcePath));
+        } else {
+            this.put(targetPath, content.get(sourcePath));
+        }
     }
 
     public byte[] toZip() throws IOException {
-        final ByteArrayOutputStream baos = new ByteArrayOutputStream(4 * 1024 * 1024);
-        final ZipOutputStream zipOutputStream = new ZipOutputStream(baos);
-        zipOutputStream.setLevel(Deflater.BEST_SPEED);
-        for (String path : this.getFilesDeep("", "")) {
-            final ZipEntry entry = new ZipEntry(path);
-            entry.setTime(0L);
-            zipOutputStream.putNextEntry(entry);
-            zipOutputStream.write(this.get(path));
-            zipOutputStream.closeEntry();
-        }
-        zipOutputStream.close();
-        return baos.toByteArray();
+        final var output = UnsynchronizedByteArrayOutputStream.builder().setBufferSize(4 * 1024 * 1024).get();
+        this.writeZip(output);
+        return output.toByteArray();
+    }
+
+    /** Writes the deterministic archive and closes the supplied output. */
+    public void writeZip(final OutputStream output) throws IOException {
+        ResourcePackZipWriter.write(this, output);
     }
 
     public static class LazyImage {

src/main/java/net/raphimc/viabedrock/api/resourcepack/content/DirectoryContent.java

@@ -89,7 +89,7 @@ public byte[] get(final String path) {
     }
 
     @Override
-    public boolean put(final String path, final byte[] data) {
+    protected boolean putBytes(final String path, final byte[] data) {
         final boolean exists = this.contains(path);
         try {
             Files.write(this.resolvePath(this.dir, Path.of(path)), data);

src/main/java/net/raphimc/viabedrock/api/resourcepack/content/InMemoryContent.java

@@ -47,7 +47,7 @@ public byte[] get(final String path) {
     }
 
     @Override
-    public boolean put(final String path, final byte[] data) {
+    protected boolean putBytes(final String path, final byte[] data) {
         return this.content.put(path, data) != null;
     }