Prevent projectiles from blocking the player's vision (#2472)

Prevent Snowballs, Eggs, and other throwable projectiles from blocking the player's screen

bootstrap/standalone/pom.xml

@@ -43,17 +43,17 @@
         <dependency>
             <groupId>org.jline</groupId>
             <artifactId>jline-terminal</artifactId>
-            <version>3.9.0</version>
+            <version>3.20.0</version>
         </dependency>
         <dependency>
             <groupId>org.jline</groupId>
             <artifactId>jline-terminal-jna</artifactId>
-            <version>3.9.0</version>
+            <version>3.20.0</version>
         </dependency>
         <dependency>
             <groupId>org.jline</groupId>
             <artifactId>jline-reader</artifactId>
-            <version>3.9.0</version>
+            <version>3.20.0</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>

connector/src/main/java/org/geysermc/connector/entity/Entity.java

@@ -249,10 +249,7 @@ public class Entity {
                     // Swimming is ignored here and instead we rely on the pose
                     metadata.getFlags().setFlag(EntityFlag.GLIDING, (xd & 0x80) == 0x80);
 
-                    // Armour stands are handled in their own class
+                    setInvisible(session, (xd & 0x20) == 0x20);
-                    if (!this.is(ArmorStandEntity.class)) {
-                        metadata.getFlags().setFlag(EntityFlag.INVISIBLE, (xd & 0x20) == 0x20);
-                    }
                 }
                 break;
             case 1: // Air/bubbles
@@ -343,6 +340,16 @@ public class Entity {
         return 300;
     }
 
+    /**
+     * Set a boolean - whether the entity is invisible or visible
+     *
+     * @param session the Geyser session
+     * @param value true if the entity is invisible
+     */
+    protected void setInvisible(GeyserSession session, boolean value) {
+        metadata.getFlags().setFlag(EntityFlag.INVISIBLE, value);
+    }
+
     /**
      * x = Pitch, y = HeadYaw, z = Yaw
      *

connector/src/main/java/org/geysermc/connector/entity/ThrowableItemEntity.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2019-2021 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.connector.entity;
+
+import com.nukkitx.math.vector.Vector3f;
+import com.nukkitx.protocol.bedrock.data.entity.EntityFlag;
+import org.geysermc.connector.entity.type.EntityType;
+import org.geysermc.connector.network.session.GeyserSession;
+
+/**
+ * Used as a class for any projectile entity that looks like an item
+ */
+public class ThrowableItemEntity extends ThrowableEntity {
+    /**
+     * Number of ticks since the entity was spawned by the Java server
+     */
+    private int age;
+    private boolean invisible;
+
+    public ThrowableItemEntity(long entityId, long geyserId, EntityType entityType, Vector3f position, Vector3f motion, Vector3f rotation) {
+        super(entityId, geyserId, entityType, position, motion, rotation);
+        metadata.getFlags().setFlag(EntityFlag.INVISIBLE, true);
+        invisible = false;
+    }
+
+    private void checkVisibility(GeyserSession session) {
+        if (invisible != metadata.getFlags().getFlag(EntityFlag.INVISIBLE)) {
+            if (!invisible) {
+                Vector3f playerPos = session.getPlayerEntity().getPosition();
+                // Prevent projectiles from blocking the player's screen
+                if (age >= 4 || position.distanceSquared(playerPos) > 16) {
+                    metadata.getFlags().setFlag(EntityFlag.INVISIBLE, false);
+                    updateBedrockMetadata(session);
+                }
+            } else {
+                metadata.getFlags().setFlag(EntityFlag.INVISIBLE, true);
+                updateBedrockMetadata(session);
+            }
+        }
+        age++;
+    }
+
+    @Override
+    public void tick(GeyserSession session) {
+        checkVisibility(session);
+        super.tick(session);
+    }
+
+    @Override
+    protected void setInvisible(GeyserSession session, boolean value) {
+        invisible = value;
+    }
+}

connector/src/main/java/org/geysermc/connector/entity/ThrownPotionEntity.java

@@ -41,7 +41,7 @@ import org.geysermc.connector.registry.type.ItemMapping;
 
 import java.util.EnumSet;
 
-public class ThrownPotionEntity extends ThrowableEntity {
+public class ThrownPotionEntity extends ThrowableItemEntity {
     private static final EnumSet<Potion> NON_ENCHANTED_POTIONS = EnumSet.of(Potion.WATER, Potion.MUNDANE, Potion.THICK, Potion.AWKWARD);
 
     public ThrownPotionEntity(long entityId, long geyserId, EntityType entityType, Vector3f position, Vector3f motion, Vector3f rotation) {

connector/src/main/java/org/geysermc/connector/entity/living/ArmorStandEntity.java

@@ -116,15 +116,7 @@ public class ArmorStandEntity extends LivingEntity {
     @Override
     public void updateBedrockMetadata(EntityMetadata entityMetadata, GeyserSession session) {
         super.updateBedrockMetadata(entityMetadata, session);
-        if (entityMetadata.getId() == 0 && entityMetadata.getType() == MetadataType.BYTE) {
+        if (entityMetadata.getId() == 2) {
-            byte xd = (byte) entityMetadata.getValue();
-
-            // Check if the armour stand is invisible and store accordingly
-            if (primaryEntity) {
-                isInvisible = (xd & 0x20) == 0x20;
-                updateSecondEntityStatus(false);
-            }
-        } else if (entityMetadata.getId() == 2) {
             updateSecondEntityStatus(false);
         } else if (entityMetadata.getId() == 15 && entityMetadata.getType() == MetadataType.BYTE) {
             byte xd = (byte) entityMetadata.getValue();
@@ -242,6 +234,15 @@ public class ArmorStandEntity extends LivingEntity {
         }
     }
 
+    @Override
+    protected void setInvisible(GeyserSession session, boolean value) {
+        // Check if the armour stand is invisible and store accordingly
+        if (primaryEntity) {
+            isInvisible = value;
+            updateSecondEntityStatus(false);
+        }
+    }
+
     @Override
     public void setHelmet(ItemData helmet) {
         super.setHelmet(helmet);

connector/src/main/java/org/geysermc/connector/entity/type/EntityType.java

@@ -107,7 +107,7 @@ public enum EntityType {
     PRIMED_TNT(TNTEntity.class, 65, 0.98f, 0.98f, 0.98f, 0f, "minecraft:tnt"),
     FALLING_BLOCK(FallingBlockEntity.class, 66, 0.98f, 0.98f),
     MOVING_BLOCK(Entity.class, 67, 0f),
-    THROWN_EXP_BOTTLE(ThrowableEntity.class, 68, 0.25f, 0.25f, 0f, 0f, "minecraft:xp_bottle"),
+    THROWN_EXP_BOTTLE(ThrowableItemEntity.class, 68, 0.25f, 0.25f, 0f, 0f, "minecraft:xp_bottle"),
     EXPERIENCE_ORB(ExpOrbEntity.class, 69, 0f, 0f, 0f, 0f, "minecraft:xp_orb"),
     EYE_OF_ENDER(Entity.class, 70, 0.25f, 0.25f, 0f, 0f, "minecraft:eye_of_ender_signal"),
     END_CRYSTAL(EnderCrystalEntity.class, 71, 2.0f, 2.0f, 2.0f, 0f, "minecraft:ender_crystal"),
@@ -121,13 +121,13 @@ public enum EntityType {
     DRAGON_FIREBALL(ItemedFireballEntity.class, 79, 1.0f),
     ARROW(TippedArrowEntity.class, 80, 0.25f, 0.25f),
     SPECTRAL_ARROW(AbstractArrowEntity.class, 80, 0.25f, 0.25f, 0.25f, 0f, "minecraft:arrow"),
-    SNOWBALL(ThrowableEntity.class, 81, 0.25f),
+    SNOWBALL(ThrowableItemEntity.class, 81, 0.25f),
-    THROWN_EGG(ThrowableEntity.class, 82, 0.25f, 0.25f, 0.25f, 0f, "minecraft:egg"),
+    THROWN_EGG(ThrowableItemEntity.class, 82, 0.25f, 0.25f, 0.25f, 0f, "minecraft:egg"),
     PAINTING(PaintingEntity.class, 83, 0f),
     MINECART(MinecartEntity.class, 84, 0.7f, 0.98f, 0.98f, 0.35f),
     FIREBALL(ItemedFireballEntity.class, 85, 1.0f),
     THROWN_POTION(ThrownPotionEntity.class, 86, 0.25f, 0.25f, 0.25f, 0f, "minecraft:splash_potion"),
-    THROWN_ENDERPEARL(ThrowableEntity.class, 87, 0.25f, 0.25f, 0.25f, 0f, "minecraft:ender_pearl"),
+    THROWN_ENDERPEARL(ThrowableItemEntity.class, 87, 0.25f, 0.25f, 0.25f, 0f, "minecraft:ender_pearl"),
     LEASH_KNOT(LeashKnotEntity.class, 88, 0.5f, 0.375f),
     WITHER_SKULL(WitherSkullEntity.class, 89, 0.3125f),
     BOAT(BoatEntity.class, 90, 0.6f, 1.6f, 1.6f, 0.35f),

connector/src/main/java/org/geysermc/connector/network/session/GeyserSession.java

@@ -75,6 +75,7 @@ import org.geysermc.connector.common.AuthType;
 import org.geysermc.connector.configuration.EmoteOffhandWorkaroundOption;
 import org.geysermc.connector.entity.Entity;
 import org.geysermc.connector.entity.ItemFrameEntity;
+import org.geysermc.connector.entity.ThrowableEntity;
 import org.geysermc.connector.entity.Tickable;
 import org.geysermc.connector.entity.attribute.GeyserAttributeType;
 import org.geysermc.connector.entity.player.SessionPlayerEntity;
@@ -904,21 +905,25 @@ public class GeyserSession implements CommandSender {
      * Called every 50 milliseconds - one Minecraft tick.
      */
     protected void tick() {
-        // Check to see if the player's position needs updating - a position update should be sent once every 3 seconds
+        try {
-        if (spawned && (System.currentTimeMillis() - lastMovementTimestamp) > 3000) {
+            // Check to see if the player's position needs updating - a position update should be sent once every 3 seconds
-            // Recalculate in case something else changed position
+            if (spawned && (System.currentTimeMillis() - lastMovementTimestamp) > 3000) {
-            Vector3d position = collisionManager.adjustBedrockPosition(playerEntity.getPosition(), playerEntity.isOnGround());
+                // Recalculate in case something else changed position
-            // A null return value cancels the packet
+                Vector3d position = collisionManager.adjustBedrockPosition(playerEntity.getPosition(), playerEntity.isOnGround());
-            if (position != null) {
+                // A null return value cancels the packet
-                ClientPlayerPositionPacket packet = new ClientPlayerPositionPacket(playerEntity.isOnGround(),
+                if (position != null) {
-                        position.getX(), position.getY(), position.getZ());
+                    ClientPlayerPositionPacket packet = new ClientPlayerPositionPacket(playerEntity.isOnGround(),
-                sendDownstreamPacket(packet);
+                            position.getX(), position.getY(), position.getZ());
+                    sendDownstreamPacket(packet);
+                }
+                lastMovementTimestamp = System.currentTimeMillis();
             }
-            lastMovementTimestamp = System.currentTimeMillis();
-        }
 
-        for (Tickable entity : entityCache.getTickableEntities()) {
+            for (Tickable entity : entityCache.getTickableEntities()) {
-            entity.tick(this);
+                entity.tick(this);
+            }
+        } catch (Throwable throwable) {
+            throwable.printStackTrace();
         }
     }