we are at the end game

src/main/java/net/gensokyoreimagined/nitori/common/chunkwatching/PlayerClientVDTracking.java

@@ -0,0 +1,9 @@
+package net.gensokyoreimagined.nitori.common.chunkwatching;
+
+public interface PlayerClientVDTracking {
+
+    boolean isClientViewDistanceChanged();
+
+    int getClientViewDistance();
+
+}

src/main/java/net/gensokyoreimagined/nitori/mixin/entity/fast_hand_swing/LivingEntityMixin.java

@@ -0,0 +1,28 @@
+package net.gensokyoreimagined.nitori.mixin.entity.fast_hand_swing;
+
+import net.minecraft.world.entity.LivingEntity;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(LivingEntity.class)
+public abstract class LivingEntityMixin {
+    @Shadow
+    public boolean swinging;
+
+    @Shadow
+    public int swingTime;
+
+    @Inject(
+            method = "updateSwingTime",
+            at = @At("HEAD"),
+            cancellable = true
+    )
+    private void skipGetDuration(CallbackInfo ci) {
+        if (!this.swinging && this.swingTime == 0) {
+            ci.cancel();
+        }
+    }
+}

src/main/java/net/gensokyoreimagined/nitori/mixin/playerwatching/MixinChunkFilter.java

@@ -0,0 +1,22 @@
+package net.gensokyoreimagined.nitori.mixin.playerwatching;
+
+import net.minecraft.server.level.ChunkTrackingView;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+
+@Mixin(ChunkTrackingView.class)
+public interface MixinChunkFilter {
+
+    /**
+     * @author ishland
+     * @reason use chebyshev distance
+     */
+    @Overwrite
+    static boolean isWithinDistance(int centerX, int centerZ, int viewDistance, int x, int z, boolean includeEdge) {
+        int actualViewDistance = viewDistance + (includeEdge ? 1 : 0);
+        int xDistance = Math.abs(centerX - x);
+        int zDistance = Math.abs(centerZ - z);
+        return xDistance <= actualViewDistance && zDistance <= actualViewDistance;
+    }
+
+}

src/main/java/net/gensokyoreimagined/nitori/mixin/playerwatching/MixinServerPlayerEntity.java

@@ -0,0 +1,46 @@
+package net.gensokyoreimagined.nitori.mixin.playerwatching;
+
+import net.gensokyoreimagined.nitori.common.chunkwatching.PlayerClientVDTracking;
+import net.minecraft.server.level.ClientInformation;
+import net.minecraft.server.level.ServerPlayer;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(ServerPlayer.class)
+public class MixinServerPlayerEntity implements PlayerClientVDTracking {
+
+    @Unique
+    private boolean vdChanged = false;
+
+    @Unique
+    private int clientVD = 2;
+
+    @Inject(method = "updateOptions", at = @At("HEAD"))
+    private void onClientSettingsChanged(ClientInformation packet, CallbackInfo ci) {
+        final int currentVD = packet.viewDistance();
+        if (currentVD != this.clientVD) this.vdChanged = true;
+        this.clientVD = Math.max(2, currentVD);
+    }
+
+    @Inject(method = "restoreFrom", at = @At("RETURN"))
+    private void onPlayerCopy(ServerPlayer oldPlayer, boolean alive, CallbackInfo ci) {
+        this.clientVD = ((PlayerClientVDTracking) oldPlayer).getClientViewDistance();
+        this.vdChanged = true;
+    }
+
+    @Unique
+    @Override
+    public boolean isClientViewDistanceChanged() {
+        return this.vdChanged;
+    }
+
+    @Unique
+    @Override
+    public int getClientViewDistance() {
+        this.vdChanged = false;
+        return this.clientVD;
+    }
+}

src/main/java/net/gensokyoreimagined/nitori/mixin/playerwatching/optimize_nearby_player_lookups/MixinMobEntity.java

@@ -0,0 +1,35 @@
+package net.gensokyoreimagined.nitori.mixin.playerwatching.optimize_nearby_player_lookups;
+
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.entity.EntityType;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.entity.Mob;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.level.Level;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import java.util.List;
+import java.util.function.Predicate;
+
+@Mixin(Mob.class)
+public abstract class MixinMobEntity extends LivingEntity {
+
+    protected MixinMobEntity(EntityType<? extends LivingEntity> entityType, Level world) {
+        super(entityType, world);
+    }
+
+    @Redirect(method = "checkDespawn", at = @At(value = "INVOKE", target = "Lnet/minecraft/world/level/Level;findNearbyPlayer(Lnet/minecraft/world/entity/Entity;DLjava/util/function/Predicate;)Lnet/minecraft/world/entity/player/Player;"))
+    private Player redirectGetClosestPlayer(Level instance, Entity entity, double v, Predicate predicate) {
+        final Player closestPlayer = instance.getNearestPlayer(entity, this.getType().getCategory().getDespawnDistance());
+        if (closestPlayer != null) {
+            return closestPlayer;
+        } else {
+            final List<? extends Player> players = this.level().players();
+            if (players.isEmpty()) return null;
+            return players.get(0);
+        }
+    }
+
+}

src/main/resources/mixins.core.json

@@ -39,6 +39,7 @@
     "shapes.blockstate_cache.BlockMixin",
     "shapes.lazy_shape_context.EntityShapeContextMixin",
     "entity.fast_retrieval.SectionedEntityCacheMixin",
+    "entity.fast_hand_swing.LivingEntityMixin",
     "math.fast_blockops.DirectionMixin",
     "math.fast_blockops.BlockPosMixin",
     "math.fast_util.AxisCycleDirectionMixin$ForwardMixin",
@@ -61,6 +62,8 @@
     "util.accessors.EntityTrackingSectionAccessor",
     "util.accessors.ServerEntityManagerAccessor",
     "util.block_tracking.AbstractBlockStateMixin",
-    "MixinEntityTickList"
+    "playerwatching.MixinChunkFilter",
+    "playerwatching.MixinServerPlayerEntity",
+    "playerwatching.optimize_nearby_player_lookups.MixinMobEntity"
   ]
 }