Add support for basic display entities

core/src/main/java/org/geysermc/geyser/entity/EntityDefinitions.java

@@ -148,6 +148,7 @@ public final class EntityDefinitions {
     public static final EntityDefinition<AbstractSkeletonEntity> STRAY;
     public static final EntityDefinition<StriderEntity> STRIDER;
     public static final EntityDefinition<TadpoleEntity> TADPOLE;
+    public static final EntityDefinition<TextDisplayEntity> TEXT_DISPLAY;
     public static final EntityDefinition<TNTEntity> TNT;
     public static final EntityDefinition<MinecartEntity> TNT_MINECART;
     public static final EntityDefinition<TraderLlamaEntity> TRADER_LLAMA;
@@ -295,6 +296,28 @@ public final class EntityDefinitions {
                     .addTranslator(MetadataType.INT, TNTEntity::setFuseLength)
                     .build();
 
+            EntityDefinition<Entity> displayBase = EntityDefinition.inherited(entityBase.factory(), entityBase)
+                    .addTranslator(null) // Interpolation start ticks
+                    .addTranslator(null) // Interpolation duration ID
+                    .addTranslator(null) // Translation
+                    .addTranslator(null) // Scale
+                    .addTranslator(null) // Left rotation
+                    .addTranslator(null) // Right rotation
+                    .addTranslator(null) // Billboard render constraints
+                    .addTranslator(null) // Brightness override
+                    .addTranslator(null) // View range
+                    .addTranslator(null) // Shadow radius
+                    .addTranslator(null) // Shadow strength
+                    .addTranslator(null) // Width
+                    .addTranslator(null) // Height
+                    .addTranslator(null) // Glow color override
+                    .build();
+            TEXT_DISPLAY = EntityDefinition.inherited(TextDisplayEntity::new, displayBase)
+                    .type(EntityType.TEXT_DISPLAY)
+                    .identifier("minecraft:armor_stand")
+                    .addTranslator(MetadataType.CHAT, TextDisplayEntity::setText)
+                    .build();
+
             EntityDefinition<FireballEntity> fireballBase = EntityDefinition.inherited(FireballEntity::new, entityBase)
                     .addTranslator(null) // Item
                     .build();

core/src/main/java/org/geysermc/geyser/entity/type/TextDisplayEntity.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2019-2023 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.entity.type;
+
+import com.github.steveice10.mc.protocol.data.game.entity.metadata.EntityMetadata;
+import com.nukkitx.math.vector.Vector3f;
+import com.nukkitx.protocol.bedrock.data.entity.EntityData;
+import net.kyori.adventure.text.Component;
+import org.geysermc.geyser.entity.EntityDefinition;
+import org.geysermc.geyser.session.GeyserSession;
+import org.geysermc.geyser.translator.text.MessageTranslator;
+
+import java.util.UUID;
+
+// Note: 1.19.4 requires that the billboard is set to something in order to show, on Java Edition
+public class TextDisplayEntity extends Entity {
+    public TextDisplayEntity(GeyserSession session, int entityId, long geyserId, UUID uuid, EntityDefinition<?> definition, Vector3f position, Vector3f motion, float yaw, float pitch, float headYaw) {
+        super(session, entityId, geyserId, uuid, definition, position, motion, yaw, pitch, headYaw);
+    }
+
+    @Override
+    protected void initializeMetadata() {
+        super.initializeMetadata();
+        // Remove armor stand body
+        this.dirtyMetadata.put(EntityData.SCALE, 0f);
+        this.dirtyMetadata.put(EntityData.NAMETAG_ALWAYS_SHOW, (byte) 1);
+    }
+
+    public void setText(EntityMetadata<Component, ?> entityMetadata) {
+        this.dirtyMetadata.put(EntityData.NAMETAG, MessageTranslator.convertMessage(entityMetadata.getValue()));
+    }
+}