probably increase performance by a lot

src/main/java/de/ellpeck/prettypipes/network/NetworkLocation.java

@@ -1,7 +1,5 @@
 package de.ellpeck.prettypipes.network;
 
-import com.google.common.collect.ArrayListMultimap;
-import com.google.common.collect.ListMultimap;
 import de.ellpeck.prettypipes.misc.ItemEqualityType;
 import de.ellpeck.prettypipes.pipe.PipeTileEntity;
 import net.minecraft.item.ItemStack;
@@ -12,9 +10,11 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.INBTSerializable;
 import net.minecraftforge.items.IItemHandler;
-import org.apache.commons.lang3.tuple.Pair;
 
-import java.util.*;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 public class NetworkLocation implements INBTSerializable<CompoundNBT> {
@@ -37,17 +37,16 @@ public class NetworkLocation implements INBTSerializable<CompoundNBT> {
         if (this.isEmpty(world))
             return Collections.emptyList();
         return this.getItems(world).entrySet().stream()
-                .filter(e -> ItemEqualityType.compareItems(e.getValue(), stack, equalityTypes))
+                .filter(kv -> ItemEqualityType.compareItems(kv.getValue(), stack, equalityTypes) && this.canExtract(world, kv.getKey()))
-                .map(Map.Entry::getKey)
+                .map(Map.Entry::getKey).collect(Collectors.toList());
-                .collect(Collectors.toList());
     }
 
     public int getItemAmount(World world, ItemStack stack, ItemEqualityType... equalityTypes) {
         if (this.isEmpty(world))
             return 0;
-        return this.getItems(world).values().stream()
+        return this.getItems(world).entrySet().stream()
-                .filter(i -> ItemEqualityType.compareItems(stack, i, equalityTypes))
+                .filter(kv -> ItemEqualityType.compareItems(stack, kv.getValue(), equalityTypes) && this.canExtract(world, kv.getKey()))
-                .mapToInt(ItemStack::getCount).sum();
+                .mapToInt(kv -> kv.getValue().getCount()).sum();
     }
 
     public Map<Integer, ItemStack> getItems(World world) {
@@ -55,19 +54,25 @@ public class NetworkLocation implements INBTSerializable<CompoundNBT> {
             IItemHandler handler = this.getItemHandler(world);
             if (handler != null) {
                 for (int i = 0; i < handler.getSlots(); i++) {
+                    ItemStack stack = handler.getStackInSlot(i);
                     // check if the slot is accessible to us
-                    if (handler.extractItem(i, 1, true).isEmpty())
+                    if (stack.isEmpty())
                         continue;
                     if (this.itemCache == null)
                         this.itemCache = new HashMap<>();
                     // use getStackInSlot since there might be more than 64 items in there
-                    this.itemCache.put(i, handler.getStackInSlot(i));
+                    this.itemCache.put(i, stack);
                 }
             }
         }
         return this.itemCache;
     }
 
+    public boolean canExtract(World world, int slot) {
+        IItemHandler handler = this.getItemHandler(world);
+        return handler != null && !handler.extractItem(slot, 1, true).isEmpty();
+    }
+
     public IItemHandler getItemHandler(World world) {
         if (this.handlerCache == null) {
             PipeNetwork network = PipeNetwork.get(world);

src/main/java/de/ellpeck/prettypipes/pipe/PipeTileEntity.java

@@ -36,6 +36,7 @@ import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.api.distmarker.OnlyIn;
 import net.minecraftforge.common.capabilities.Capability;
 import net.minecraftforge.common.util.Constants.NBT;
+import net.minecraftforge.common.util.Lazy;
 import net.minecraftforge.common.util.LazyOptional;
 import net.minecraftforge.items.CapabilityItemHandler;
 import net.minecraftforge.items.IItemHandler;
@@ -76,6 +77,7 @@ public class PipeTileEntity extends TileEntity implements INamedContainerProvide
     private int lastItemAmount;
     private int priority;
     private final LazyOptional<PipeTileEntity> lazyThis = LazyOptional.of(() -> this);
+    private final Lazy<Integer> workRandomizer = Lazy.of(() -> this.world.rand.nextInt(200));
 
     public PipeTileEntity() {
         this(Registry.pipeTileEntity);
@@ -384,6 +386,10 @@ public class PipeTileEntity extends TileEntity implements INamedContainerProvide
         this.cover = null;
     }
 
+    public boolean shouldWorkNow(int speed) {
+        return (this.world.getGameTime() + this.workRandomizer.get()) % speed == 0;
+    }
+
     @Override
     public void remove() {
         super.remove();

src/main/java/de/ellpeck/prettypipes/pipe/modules/craft/CraftingModuleItem.java

@@ -66,7 +66,7 @@ public class CraftingModuleItem extends ModuleItem {
 
     @Override
     public void tick(ItemStack module, PipeTileEntity tile) {
-        if (tile.getWorld().getGameTime() % this.speed != 0 || !tile.canWork())
+        if (!tile.shouldWorkNow(this.speed) || !tile.canWork())
             return;
         PipeNetwork network = PipeNetwork.get(tile.getWorld());
         // process crafting ingredient requests

src/main/java/de/ellpeck/prettypipes/pipe/modules/extraction/ExtractionModuleItem.java

@@ -1,12 +1,12 @@
 package de.ellpeck.prettypipes.pipe.modules.extraction;
 
 import de.ellpeck.prettypipes.Registry;
-import de.ellpeck.prettypipes.items.ModuleItem;
-import de.ellpeck.prettypipes.misc.ItemFilter;
-import de.ellpeck.prettypipes.pipe.PipeTileEntity;
 import de.ellpeck.prettypipes.items.IModule;
+import de.ellpeck.prettypipes.items.ModuleItem;
 import de.ellpeck.prettypipes.items.ModuleTier;
+import de.ellpeck.prettypipes.misc.ItemFilter;
 import de.ellpeck.prettypipes.network.PipeNetwork;
+import de.ellpeck.prettypipes.pipe.PipeTileEntity;
 import de.ellpeck.prettypipes.pipe.containers.AbstractPipeContainer;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.entity.player.PlayerInventory;
@@ -31,9 +31,7 @@ public class ExtractionModuleItem extends ModuleItem {
 
     @Override
     public void tick(ItemStack module, PipeTileEntity tile) {
-        if (tile.getWorld().getGameTime() % this.speed != 0)
+        if (!tile.shouldWorkNow(this.speed) || !tile.canWork())
-            return;
-        if (!tile.canWork())
             return;
         ItemFilter filter = new ItemFilter(this.filterSlots, module, tile);
 

src/main/java/de/ellpeck/prettypipes/pipe/modules/retrieval/RetrievalModuleItem.java

@@ -31,9 +31,7 @@ public class RetrievalModuleItem extends ModuleItem {
 
     @Override
     public void tick(ItemStack module, PipeTileEntity tile) {
-        if (tile.getWorld().getGameTime() % this.speed != 0)
+        if (!tile.shouldWorkNow(this.speed) || !tile.canWork())
-            return;
-        if (!tile.canWork())
             return;
         PipeNetwork network = PipeNetwork.get(tile.getWorld());
 

src/main/java/de/ellpeck/prettypipes/terminal/ItemTerminalTileEntity.java

@@ -176,10 +176,13 @@ public class ItemTerminalTileEntity extends TileEntity implements INamedContaine
         PipeTileEntity pipe = this.getConnectedPipe();
         Map<EquatableItemStack, NetworkItem> items = new HashMap<>();
         for (NetworkLocation location : network.getOrderedNetworkItems(pipe.getPos())) {
-            for (ItemStack stack : location.getItems(this.world).values()) {
+            for (Map.Entry<Integer, ItemStack> entry : location.getItems(this.world).entrySet()) {
-                EquatableItemStack equatable = new EquatableItemStack(stack, equalityTypes);
+                // make sure we can extract from this slot to display it
+                if (!location.canExtract(this.world, entry.getKey()))
+                    continue;
+                EquatableItemStack equatable = new EquatableItemStack(entry.getValue(), equalityTypes);
                 NetworkItem item = items.computeIfAbsent(equatable, NetworkItem::new);
-                item.add(location, stack);
+                item.add(location, entry.getValue());
             }
         }
         network.endProfile();