Add tickets to keep entity chunks loaded

Author: Samsuik

patches/server/0009-Load-Chunks-on-Movement.patch

@@ -4,8 +4,53 @@ Date: Sat, 11 Sep 2021 19:19:41 +0100
 Subject: [PATCH] Load Chunks on Movement
 
 
+diff --git a/src/main/java/io/papermc/paper/util/CollisionUtil.java b/src/main/java/io/papermc/paper/util/CollisionUtil.java
+index bfb1de19f53d5d7c7b65e25a606fabfa416706b3..ae2eede559bd9fe7e500ce180f2ac102a95d3856 100644
+--- a/src/main/java/io/papermc/paper/util/CollisionUtil.java
++++ b/src/main/java/io/papermc/paper/util/CollisionUtil.java
+@@ -1595,6 +1595,7 @@ public final class CollisionUtil {
+     public static final int COLLISION_FLAG_COLLIDE_WITH_UNLOADED_CHUNKS = 1 << 1;
+     public static final int COLLISION_FLAG_CHECK_BORDER = 1 << 2;
+     public static final int COLLISION_FLAG_CHECK_ONLY = 1 << 3;
++    public static final int COLLISION_FLAG_ADD_TICKET = 1 << 4; // Sakura
+ 
+     public static boolean getCollisionsForBlocksOrWorldBorder(final Level world, final Entity entity, final AABB aabb,
+                                                               final List<VoxelShape> intoVoxel, final List<AABB> intoAABB,
+@@ -1644,11 +1645,20 @@ public final class CollisionUtil {
+         final int maxChunkZ = maxBlockZ >> 4;
+ 
+         final boolean loadChunks = (collisionFlags & COLLISION_FLAG_LOAD_CHUNKS) != 0;
++        final boolean addTicket  = (collisionFlags & COLLISION_FLAG_ADD_TICKET) != 0; // Sakura
+         final ServerChunkCache chunkSource = (ServerChunkCache)world.getChunkSource();
+ 
+         for (int currChunkZ = minChunkZ; currChunkZ <= maxChunkZ; ++currChunkZ) {
+             for (int currChunkX = minChunkX; currChunkX <= maxChunkX; ++currChunkX) {
+                 final ChunkAccess chunk = loadChunks ? chunkSource.getChunk(currChunkX, currChunkZ, ChunkStatus.FULL, true) : chunkSource.getChunkAtIfLoadedImmediately(currChunkX, currChunkZ);
++                // Sakura start - keep chunks loaded on movement
++                if (addTicket) {
++                    chunkSource.chunkMap.getDistanceManager().getChunkHolderManager().addTicketAtLevel(net.minecraft.server.level.TicketType.ENTITY_MOVEMENT, currChunkX, currChunkZ, 33, CoordinateUtils.getChunkKey(currChunkX, currChunkZ));
++                    // This is known to work, uncomment if any issues
++                    // var pos = new net.minecraft.world.level.ChunkPos(currChunkX, currChunkZ);
++                    // chunkSource.addTicketAtLevel(net.minecraft.server.level.TicketType.ENTITY_MOVEMENT, pos, 33, pos.toLong());
++                }
++                // Sakura end
+ 
+                 if (chunk == null) {
+                     if ((collisionFlags & COLLISION_FLAG_COLLIDE_WITH_UNLOADED_CHUNKS) != 0) {
+diff --git a/src/main/java/net/minecraft/server/level/TicketType.java b/src/main/java/net/minecraft/server/level/TicketType.java
+index 658e63ebde81dc14c8ab5850fb246dc0aab25dea..f1ff1a67fee37ee7b241ceaa164fa4ee64d3767b 100644
+--- a/src/main/java/net/minecraft/server/level/TicketType.java
++++ b/src/main/java/net/minecraft/server/level/TicketType.java
+@@ -37,6 +37,7 @@ public class TicketType<T> {
+     public static final TicketType<Long> NON_FULL_SYNC_LOAD = create("non_full_sync_load", Long::compareTo);
+     public static final TicketType<ChunkPos> DELAY_UNLOAD = create("delay_unload", Comparator.comparingLong(ChunkPos::toLong), 1);
+     // Paper end - rewrite chunk system
++    public static final TicketType<Long> ENTITY_MOVEMENT = create("entity_movement", Long::compareTo, 10 * 20); // Sakura
+ 
+     public static <T> TicketType<T> create(String name, Comparator<T> argumentComparator) {
+         return new TicketType<>(name, argumentComparator, 0L);
 diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
-index 514c34e25b6e42fa591ccbcd134149e64235b899..c35ca0785ecc268fb7e20dee56d42bdadca41ee6 100644
+index 514c34e25b6e42fa591ccbcd134149e64235b899..fcbccbd9aeed4ad813ebe72cbe25fa1625800bb2 100644
 --- a/src/main/java/net/minecraft/world/entity/Entity.java
 +++ b/src/main/java/net/minecraft/world/entity/Entity.java
 @@ -397,6 +397,7 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
@@ -21,7 +66,7 @@ index 514c34e25b6e42fa591ccbcd134149e64235b899..c35ca0785ecc268fb7e20dee56d42bda
          io.papermc.paper.util.CollisionUtil.getCollisions(
                  world, this, collisionBox, potentialCollisionsVoxel, potentialCollisionsBB,
 -                (0),
-+                (0) | (loadChunks ? io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_LOAD_CHUNKS : 0), // Sakura
++                (loadChunks ? io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_LOAD_CHUNKS | io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_ADD_TICKET : 0), // Sakura
                  null, null
          );
 

patches/server/0020-Optimise-Fast-Movement.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Optimise Fast Movement
 
 
 diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
-index 311891f079d2136a18f62478bd289c91ff515772..01c5279084a8f84dcaf8d0d51a3305dc04476944 100644
+index 31e9e180ecddefc99d0984e793682f40258af3fb..f036b547908e5f8d1a89c32d21a35fcc778198ae 100644
 --- a/src/main/java/net/minecraft/world/entity/Entity.java
 +++ b/src/main/java/net/minecraft/world/entity/Entity.java
 @@ -1165,6 +1165,95 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
@@ -170,7 +170,7 @@ index 311891f079d2136a18f62478bd289c91ff515772..01c5279084a8f84dcaf8d0d51a3305dc
 +        // Copied from the collide method below
 +        io.papermc.paper.util.CollisionUtil.getCollisions(
 +            level, this, collisionBox, voxelList, bbList,
-+            (0) | (loadChunks ? io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_LOAD_CHUNKS : 0), // Sakura
++            (loadChunks ? io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_LOAD_CHUNKS | io.papermc.paper.util.CollisionUtil.COLLISION_FLAG_ADD_TICKET : 0), // Sakura
 +            null, null
 +        );
 +