diff options
Diffstat (limited to 'paper-server/patches/features/0018-Fix-entity-tracker-desync-when-new-players-are-added.patch')
| -rw-r--r-- | paper-server/patches/features/0018-Fix-entity-tracker-desync-when-new-players-are-added.patch | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/paper-server/patches/features/0018-Fix-entity-tracker-desync-when-new-players-are-added.patch b/paper-server/patches/features/0018-Fix-entity-tracker-desync-when-new-players-are-added.patch new file mode 100644 index 0000000000..1059713e9f --- /dev/null +++ b/paper-server/patches/features/0018-Fix-entity-tracker-desync-when-new-players-are-added.patch @@ -0,0 +1,105 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Spottedleaf <[email protected]> +Date: Tue, 20 Feb 2024 18:24:16 -0800 +Subject: [PATCH] Fix entity tracker desync when new players are added to the + tracker + +The delta position packet instructs the client to update +the entity position by a position difference. However, this position +difference is relative to the last position in the entity tracker +state, not the last position which has been sent to the player. As +a result, if the last position the player has recorded is different +than the one stored in the entity tracker (which occurs when a new +player is added to an existing entity tracker state) then the sent +position difference will cause a position desync for the client. + +We can resolve this problem by either tracking the last position +sent per-player, or by simply resetting the last sent position +in the entity tracker state every time a new player is added. +Resetting the last sent position every time a new player is +added to the tracker is just easier to do, so that is what +this patch does. + +This patch also fixes entities appearing to disappear when +teleporting to players by changing the initial position +in the spawn packet to the entities current tracking position. +When teleporting, the spawn packet will contain the old position +which is most likely in an unloaded chunk - which means that the +client will not tick the entity and thus not lerp the entity +from its old position to its new position. + +diff --git a/net/minecraft/network/protocol/game/ClientboundAddEntityPacket.java b/net/minecraft/network/protocol/game/ClientboundAddEntityPacket.java +index db31989ebe3d7021cfd2311439e9a00f819b0841..1373977b339405ef59bb3ea03d195285c96dd3fe 100644 +--- a/net/minecraft/network/protocol/game/ClientboundAddEntityPacket.java ++++ b/net/minecraft/network/protocol/game/ClientboundAddEntityPacket.java +@@ -42,9 +42,11 @@ public class ClientboundAddEntityPacket implements Packet<ClientGamePacketListen + this( + entity.getId(), + entity.getUUID(), +- serverEntity.getPositionBase().x(), +- serverEntity.getPositionBase().y(), +- serverEntity.getPositionBase().z(), ++ // Paper start - fix entity tracker desync ++ entity.trackingPosition().x(), ++ entity.trackingPosition().y(), ++ entity.trackingPosition().z(), ++ // Paper end - fix entity tracker desync + serverEntity.getLastSentXRot(), + serverEntity.getLastSentYRot(), + entity.getType(), +diff --git a/net/minecraft/server/level/ChunkMap.java b/net/minecraft/server/level/ChunkMap.java +index 3dff97f13586be3b52bbe786852c185f6753a019..ff6503bf8eb88d1264c3d848a89d0255b4b3ae68 100644 +--- a/net/minecraft/server/level/ChunkMap.java ++++ b/net/minecraft/server/level/ChunkMap.java +@@ -1208,6 +1208,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider + this.serverEntity.addPairing(player); + } + // Paper end - entity tracking events ++ this.serverEntity.onPlayerAdd(); // Paper - fix desync when a player is added to the tracker + } + } else if (this.seenBy.remove(player.connection)) { + this.serverEntity.removePairing(player); +diff --git a/net/minecraft/server/level/ServerEntity.java b/net/minecraft/server/level/ServerEntity.java +index 870b9efd445ddadb3725e88351555ad986ce7c72..a4da36060ca75968f5831adfc3f7117281649b7a 100644 +--- a/net/minecraft/server/level/ServerEntity.java ++++ b/net/minecraft/server/level/ServerEntity.java +@@ -90,6 +90,13 @@ public class ServerEntity { + this.trackedDataValues = entity.getEntityData().getNonDefaultValues(); + } + ++ // Paper start - fix desync when a player is added to the tracker ++ private boolean forceStateResync; ++ public void onPlayerAdd() { ++ this.forceStateResync = true; ++ } ++ // Paper end - fix desync when a player is added to the tracker ++ + public void sendChanges() { + // Paper start - optimise collisions + if (((ca.spottedleaf.moonrise.patches.chunk_system.entity.ChunkSystemEntity)this.entity).moonrise$isHardColliding()) { +@@ -130,7 +137,7 @@ public class ServerEntity { + this.sendDirtyEntityData(); + } + +- if (this.tickCount % this.updateInterval == 0 || this.entity.hasImpulse || this.entity.getEntityData().isDirty()) { ++ if (this.forceStateResync || this.tickCount % this.updateInterval == 0 || this.entity.hasImpulse || this.entity.getEntityData().isDirty()) { // Paper - fix desync when a player is added to the tracker + byte b = Mth.packDegrees(this.entity.getYRot()); + byte b1 = Mth.packDegrees(this.entity.getXRot()); + boolean flag = Math.abs(b - this.lastSentYRot) >= 1 || Math.abs(b1 - this.lastSentXRot) >= 1; +@@ -165,7 +172,7 @@ public class ServerEntity { + long l1 = this.positionCodec.encodeY(vec3); + long l2 = this.positionCodec.encodeZ(vec3); + boolean flag5 = l < -32768L || l > 32767L || l1 < -32768L || l1 > 32767L || l2 < -32768L || l2 > 32767L; +- if (flag5 || this.teleportDelay > 400 || this.wasRiding || this.wasOnGround != this.entity.onGround()) { ++ if (this.forceStateResync || flag5 || this.teleportDelay > 400 || this.wasRiding || this.wasOnGround != this.entity.onGround()) { // Paper - fix desync when a player is added to the tracker + this.wasOnGround = this.entity.onGround(); + this.teleportDelay = 0; + packet = ClientboundEntityPositionSyncPacket.of(this.entity); +@@ -230,6 +237,7 @@ public class ServerEntity { + } + + this.entity.hasImpulse = false; ++ this.forceStateResync = false; // Paper - fix desync when a player is added to the tracker + } + + this.tickCount++; |