diff options
| -rw-r--r-- | patches/server/0936-Workaround-for-client-lag-spikes-MC-162253.patch | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/patches/server/0936-Workaround-for-client-lag-spikes-MC-162253.patch b/patches/server/0936-Workaround-for-client-lag-spikes-MC-162253.patch new file mode 100644 index 0000000000..4e963d9792 --- /dev/null +++ b/patches/server/0936-Workaround-for-client-lag-spikes-MC-162253.patch @@ -0,0 +1,114 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Brokkonaut <[email protected]> +Date: Sat, 18 Dec 2021 19:43:36 +0100 +Subject: [PATCH] Workaround for client lag spikes (MC-162253) + +When crossing certain chunk boundaries, the client needlessly +calculates light maps for chunk neighbours. In some specific map +configurations, these calculations cause a 500ms+ freeze on the Client. + +This patch basically serves as a workaround by sending light maps +to the client, so that it doesn't attempt to calculate them. +This mitigates the frametime impact to a minimum (but it's still there). + +Original patch by: MeFisto94 <[email protected]> +Co-authored-by: =?UTF-8?q?Dani=C3=ABl=20Goossens?= <[email protected]> +Co-authored-by: Nassim Jahnke <[email protected]> + +diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java +index 77c89376495d90d0e7cbf6cd02c9a1c8d9a4340b..649355158ed435e242a48f4aaa4578bcc2a808dd 100644 +--- a/src/main/java/net/minecraft/server/level/ChunkMap.java ++++ b/src/main/java/net/minecraft/server/level/ChunkMap.java +@@ -2171,6 +2171,46 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider + + } + ++ // Paper start - Fix MC-162253 ++ /** ++ * Returns the light mask for the given chunk consisting of all non-empty sections that may need sending. ++ */ ++ private BitSet lightMask(final LevelChunk chunk) { ++ final net.minecraft.world.level.chunk.LevelChunkSection[] sections = chunk.getSections(); ++ final BitSet mask = new BitSet(this.lightEngine.getLightSectionCount()); ++ ++ // There are 2 more light sections than chunk sections so when iterating over ++ // sections we have to increment the index by 1 ++ for (int i = 0; i < sections.length; i++) { ++ if (!sections[i].hasOnlyAir()) { ++ // Whenever a section is not empty, it can change lighting for the section itself (i + 1), the section below, and the section above ++ mask.set(i); ++ mask.set(i + 1); ++ mask.set(i + 2); ++ i++; // We can skip the already set upper section ++ } ++ } ++ return mask; ++ } ++ ++ /** ++ * Returns the ceiling light mask of all sections that are equal or lower to the highest non-empty section. ++ */ ++ private BitSet ceilingLightMask(final LevelChunk chunk) { ++ final net.minecraft.world.level.chunk.LevelChunkSection[] sections = chunk.getSections(); ++ for (int i = sections.length - 1; i >= 0; i--) { ++ if (!sections[i].hasOnlyAir()) { ++ // Add one to get the light section, one because blocks in the section above may change, and another because BitSet's toIndex is exclusive ++ final int highest = i + 3; ++ final BitSet mask = new BitSet(highest); ++ mask.set(0, highest); ++ return mask; ++ } ++ } ++ return new BitSet(); ++ } ++ // Paper end - Fix MC-162253 ++ + // Paper start - Anti-Xray - Bypass + private void playerLoadedChunk(ServerPlayer player, MutableObject<java.util.Map<Object, ClientboundLevelChunkWithLightPacket>> cachedDataPackets, LevelChunk chunk) { + if (cachedDataPackets.getValue() == null) { +@@ -2179,6 +2219,45 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider + + Boolean shouldModify = chunk.getLevel().chunkPacketBlockController.shouldModify(player, chunk); + player.trackChunk(chunk.getPos(), (Packet) cachedDataPackets.getValue().computeIfAbsent(shouldModify, (s) -> { ++ // Paper start - Fix MC-162253 ++ final int viewDistance = getEffectiveViewDistance(); ++ final int playerChunkX = player.getBlockX() >> 4; ++ final int playerChunkZ = player.getBlockZ() >> 4; ++ ++ // For all loaded neighbours, send sky light for empty sections above highest non-empty section (+1) of the center chunk ++ // otherwise the client will try to calculate lighting there on its own ++ final BitSet lightMask = lightMask(chunk); ++ if (!lightMask.isEmpty()) { ++ for (int x = -1; x <= 1; x++) { ++ for (int z = -1; z <= 1; z++) { ++ if (x == 0 && z == 0) { ++ continue; ++ } ++ ++ if (!chunk.isNeighbourLoaded(x, z)) { ++ continue; ++ } ++ ++ final int neighborChunkX = chunk.getPos().x + x; ++ final int neighborChunkZ = chunk.getPos().z + z; ++ final int distX = Math.abs(playerChunkX - neighborChunkX); ++ final int distZ = Math.abs(playerChunkZ - neighborChunkZ); ++ if (Math.max(distX, distZ) > viewDistance) { ++ continue; ++ } ++ ++ final LevelChunk neighbor = chunk.getRelativeNeighbourIfLoaded(x, z); ++ final BitSet updateLightMask = (BitSet) lightMask.clone(); ++ updateLightMask.andNot(ceilingLightMask(neighbor)); ++ if (updateLightMask.isEmpty()) { ++ continue; ++ } ++ ++ player.connection.send(new net.minecraft.network.protocol.game.ClientboundLightUpdatePacket(new ChunkPos(neighborChunkX, neighborChunkZ), this.lightEngine, updateLightMask, null, true)); ++ } ++ } ++ } ++ // Paper end - Fix MC-162253 + return new ClientboundLevelChunkWithLightPacket(chunk, this.lightEngine, (BitSet) null, (BitSet) null, true, (Boolean) s); + })); + // Paper end |