Merge branch '1.7.10' - imports all the fluid fixups and other stuff from 1.7 into 1.8

Conflicts:
	fml/src/main/java/net/minecraftforge/fml/common/FMLCommonHandler.java
	fml/src/main/java/net/minecraftforge/fml/common/Loader.java
	patches/minecraft/net/minecraft/client/Minecraft.java.patch
	patches/minecraft/net/minecraft/client/renderer/texture/TextureMap.java.patch
	patches/minecraft/net/minecraft/item/ItemArmor.java.patch
	patches/minecraft/net/minecraft/nbt/CompressedStreamTools.java.patch
	patches/minecraft/net/minecraft/nbt/NBTTagCompound.java.patch
	patches/minecraft/net/minecraft/nbt/NBTTagList.java.patch
	patches/minecraft/net/minecraft/world/World.java.patch
	patches/minecraft/net/minecraft/world/WorldProvider.java.patch
	src/main/java/net/minecraftforge/common/ForgeVersion.java
	src/main/java/net/minecraftforge/common/network/ForgeMessage.java
	src/main/java/net/minecraftforge/fluids/BlockFluidBase.java
	src/main/java/net/minecraftforge/fluids/FluidContainerRegistry.java
	src/main/java/net/minecraftforge/fluids/FluidRegistry.java
	src/main/java/net/minecraftforge/oredict/OreDictionary.java

fml/src/main/java/net/minecraftforge/fml/client/FMLClientHandler.java

@@ -66,6 +66,7 @@ import net.minecraft.network.status.INetHandlerStatusServer;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.util.IThreadListener;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.StringUtils;
 import net.minecraft.world.WorldSettings;
 import net.minecraft.world.storage.SaveFormatOld;
 import net.minecraftforge.fml.client.registry.RenderingRegistry;
@@ -991,9 +992,17 @@ public class FMLClientHandler implements IFMLSidedHandler
     public void processWindowMessages()
     {
         // workaround for windows requiring messages being processed on the main thread
-        if(LWJGLUtil.getPlatform() == LWJGLUtil.PLATFORM_WINDOWS)
+        if (LWJGLUtil.getPlatform() != LWJGLUtil.PLATFORM_WINDOWS) return;
-        {
+        // If we can't grab the mutex, the update call is blocked, probably in native code, just skip it and carry on
-            Display.processMessages();
+        // We'll get another go next time
-        }
+        if (!SplashProgress.mutex.tryAcquire()) return;
+        Display.processMessages();
+        SplashProgress.mutex.release();
+    }
+
+    @Override
+    public String stripSpecialChars(String message)
+    {
+        return StringUtils.stripControlCodes(message);
     }
 }

fml/src/main/java/net/minecraftforge/fml/client/SplashProgress.java

@@ -63,6 +63,7 @@ import java.lang.Thread.UncaughtExceptionHandler;
 import java.nio.IntBuffer;
 import java.util.Iterator;
 import java.util.Properties;
+import java.util.concurrent.Semaphore;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 
@@ -131,6 +132,7 @@ public class SplashProgress
     private static int barBorderColor;
     private static int barColor;
     private static int barBackgroundColor;
+    static final Semaphore mutex = new Semaphore(1);
 
     private static String getString(String name, String def)
     {
@@ -352,7 +354,16 @@ public class SplashProgress
                     glEnd();
                     glDisable(GL_TEXTURE_2D);
 
+                    // We use mutex to indicate safely to the main thread that we're taking the display global lock
+                    // So the main thread can skip processing messages while we're updating.
+                    // There are system setups where this call can pause for a while, because the GL implementation
+                    // is trying to impose a framerate or other thing is occurring. Without the mutex, the main
+                    // thread would delay waiting for the same global display lock
+                    mutex.acquireUninterruptibly();
                     Display.update();
+                    // As soon as we're done, we release the mutex. The other thread can now ping the processmessages
+                    // call as often as it wants until we get get back here again
+                    mutex.release();
                     if(pause)
                     {
                         clearGL();

fml/src/main/java/net/minecraftforge/fml/common/FMLCommonHandler.java

@@ -764,4 +764,8 @@ public class FMLCommonHandler
         props.clear();
         return null;
     }
+    public String stripSpecialChars(String message)
+    {
+        return sidedDelegate != null ? sidedDelegate.stripSpecialChars(message) : message;
+    }
 }

fml/src/main/java/net/minecraftforge/fml/common/IFMLSidedHandler.java

@@ -64,4 +64,6 @@ public interface IFMLSidedHandler
     IThreadListener getWorldThread(INetHandler net);
 
     void processWindowMessages();
+
+    String stripSpecialChars(String message);
 }

fml/src/main/java/net/minecraftforge/fml/common/Loader.java

@@ -39,6 +39,7 @@ import net.minecraftforge.fml.common.functions.ArtifactVersionNameFunction;
 import net.minecraftforge.fml.common.functions.ModIdFunction;
 import net.minecraftforge.fml.common.registry.GameData;
 import net.minecraftforge.fml.common.registry.GameRegistry;
+import net.minecraftforge.fml.common.registry.ItemStackHolderInjector;
 import net.minecraftforge.fml.common.registry.ObjectHolderRegistry;
 import net.minecraftforge.fml.common.registry.GameRegistry.Type;
 import net.minecraftforge.fml.common.toposort.ModSorter;
@@ -524,8 +525,10 @@ public class Loader
             return;
         }
         ObjectHolderRegistry.INSTANCE.findObjectHolders(discoverer.getASMTable());
+        ItemStackHolderInjector.INSTANCE.findHolders(discoverer.getASMTable());
         modController.distributeStateMessage(LoaderState.PREINITIALIZATION, discoverer.getASMTable(), canonicalConfigDir);
         ObjectHolderRegistry.INSTANCE.applyObjectHolders();
+        ItemStackHolderInjector.INSTANCE.inject();
         modController.transition(LoaderState.INITIALIZATION, false);
         progressBar.step("Initializing Minecraft Engine");
     }
@@ -614,7 +617,7 @@ public class Loader
 
     public String getFMLVersionString()
     {
-        return String.format("%s.%s.%s.%s", major, minor, rev, build);
+        return "8.0.99.99";
     }
 
     public ClassLoader getModClassLoader()
@@ -708,6 +711,7 @@ public class Loader
         progressBar.step("Initializing mods Phase 3");
         modController.transition(LoaderState.POSTINITIALIZATION, false);
         modController.distributeStateMessage(FMLInterModComms.IMCEvent.class);
+        ItemStackHolderInjector.INSTANCE.inject();
         modController.distributeStateMessage(LoaderState.POSTINITIALIZATION);
         progressBar.step("Finishing up");
         modController.transition(LoaderState.AVAILABLE, false);

fml/src/main/java/net/minecraftforge/fml/common/ProgressManager.java

@@ -71,7 +71,7 @@ public class ProgressManager
         {
             if(step >= steps) throw new IllegalStateException("too much steps for ProgressBar " + title);
             step++;
-            this.message = message;
+            this.message = FMLCommonHandler.instance().stripSpecialChars(message);
             FMLCommonHandler.instance().processWindowMessages();
         }
 

fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/EventSubscriptionTransformer.java

@@ -65,7 +65,7 @@ public class EventSubscriptionTransformer implements IClassTransformer
         {
             if (buildEvents(classNode))
             {
-                ClassWriter cw = new ClassWriter(COMPUTE_MAXS | COMPUTE_FRAMES);
+                ClassWriter cw = new ClassWriter(COMPUTE_FRAMES);
                 classNode.accept(cw);
                 return cw.toByteArray();
             }

fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/MarkerTransformer.java

@@ -100,7 +100,7 @@ public class MarkerTransformer implements IClassTransformer
     @Override
     public byte[] transform(String name, String transformedName, byte[] bytes)
     {
-    	if (bytes == null) { return null; }
+        if (bytes == null) { return null; }
         if (!markers.containsKey(name)) { return bytes; }
 
         ClassNode classNode = new ClassNode();

fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/SideTransformer.java

@@ -34,7 +34,7 @@ public class SideTransformer implements IClassTransformer
     @Override
     public byte[] transform(String name, String transformedName, byte[] bytes)
     {
-    	if (bytes == null) { return null; }
+        if (bytes == null) { return null; }
 
         ClassNode classNode = new ClassNode();
         ClassReader classReader = new ClassReader(bytes);

fml/src/main/java/net/minecraftforge/fml/common/registry/GameRegistry.java

@@ -32,6 +32,10 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.item.crafting.CraftingManager;
 import net.minecraft.item.crafting.FurnaceRecipes;
 import net.minecraft.item.crafting.IRecipe;
+import net.minecraft.nbt.JsonToNBT;
+import net.minecraft.nbt.NBTBase;
+import net.minecraft.nbt.NBTException;
+import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.world.World;
@@ -47,6 +51,8 @@ import net.minecraftforge.fml.common.ObfuscationReflectionHelper;
 import org.apache.logging.log4j.Level;
 
 import com.google.common.base.Objects;
+import com.google.common.base.Strings;
+import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
@@ -451,4 +457,70 @@ public class GameRegistry
          */
         String value();
     }
+
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.FIELD)
+    public @interface ItemStackHolder
+    {
+        /**
+         * The registry name of the item being looked up.
+         * @return The registry name
+         */
+        public String value();
+
+        /**
+         * The metadata or damage value for the itemstack, defaults to 0.
+         * @return the metadata value
+         */
+        public int meta() default 0;
+
+        /**
+         * The string serialized nbt value for the itemstack. Defaults to empty for no nbt.
+         *
+         * @return a nbt string
+         */
+        public String nbt() default "";
+    }
+
+    /**
+     * Makes an {@link ItemStack} based on the itemName reference, with supplied meta, stackSize and nbt, if possible
+     *
+     * Will return null if the item doesn't exist (because it's not from a loaded mod for example)
+     * Will throw a {@link RuntimeException} if the nbtString is invalid for use in an {@link ItemStack}
+     *
+     * @param itemName a registry name reference
+     * @param meta the meta
+     * @param stackSize the stack size
+     * @param nbtString an nbt stack as a string, will be processed by {@link JsonToNBT}
+     * @return a new itemstack
+     */
+    public static ItemStack makeItemStack(String itemName, int meta, int stackSize, String nbtString)
+    {
+        if (itemName == null) throw new IllegalArgumentException("The itemName cannot be null");
+        Item item = GameData.getItemRegistry().getObject(itemName);
+        if (item == null) {
+            FMLLog.getLogger().log(Level.TRACE, "Unable to find item with name {}", itemName);
+            return null;
+        }
+        ItemStack is = new ItemStack(item,1,meta);
+        if (!Strings.isNullOrEmpty(nbtString)) {
+            NBTBase nbttag = null;
+            try
+            {
+                nbttag = JsonToNBT.func_180713_a(nbtString);
+            } catch (NBTException e)
+            {
+                FMLLog.getLogger().log(Level.WARN, "Encountered an exception parsing ItemStack NBT string {}", nbtString, e);
+                throw Throwables.propagate(e);
+            }
+            if (!(nbttag instanceof NBTTagCompound)) {
+                FMLLog.getLogger().log(Level.WARN, "Unexpected NBT string - multiple values {}", nbtString);
+                throw new RuntimeException("Invalid NBT JSON");
+            } else {
+                is.setTagCompound((NBTTagCompound) nbttag);
+            }
+        }
+        return is;
+    }
+
 }

fml/src/main/java/net/minecraftforge/fml/common/registry/ItemStackHolderInjector.java

@@ -0,0 +1,81 @@
+package net.minecraftforge.fml.common.registry;
+
+import java.lang.reflect.Field;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.minecraftforge.fml.common.FMLLog;
+import net.minecraftforge.fml.common.discovery.ASMDataTable;
+import net.minecraftforge.fml.common.discovery.ASMDataTable.ASMData;
+
+import org.apache.logging.log4j.Level;
+
+import com.google.common.base.Throwables;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+
+
+public enum ItemStackHolderInjector
+{
+    INSTANCE;
+
+    private List<ItemStackHolderRef> itemStackHolders = Lists.newArrayList();
+
+    public void inject() {
+        FMLLog.getLogger().log(Level.INFO, "Injecting itemstacks");
+        for (ItemStackHolderRef ishr: itemStackHolders) {
+            ishr.apply();
+        }
+        FMLLog.getLogger().log(Level.INFO, "Itemstack injection complete");
+    }
+
+    public void findHolders(ASMDataTable table) {
+        FMLLog.info("Identifying ItemStackHolder annotations");
+        Set<ASMData> allItemStackHolders = table.getAll(GameRegistry.ItemStackHolder.class.getName());
+        Map<String, Class<?>> classCache = Maps.newHashMap();
+        for (ASMData data : allItemStackHolders)
+        {
+            String className = data.getClassName();
+            String annotationTarget = data.getObjectName();
+            String value = (String) data.getAnnotationInfo().get("value");
+            int meta = data.getAnnotationInfo().containsKey("meta") ? (Integer) data.getAnnotationInfo().get("meta") : 0;
+            String nbt = data.getAnnotationInfo().containsKey("nbt") ? (String) data.getAnnotationInfo().get("nbt") : "";
+            addHolder(classCache, className, annotationTarget, value, meta, nbt);
+        }
+        FMLLog.info("Found %d ItemStackHolder annotations", allItemStackHolders.size());
+
+    }
+
+    private void addHolder(Map<String, Class<?>> classCache, String className, String annotationTarget, String value, Integer meta, String nbt)
+    {
+        Class<?> clazz;
+        if (classCache.containsKey(className))
+        {
+            clazz = classCache.get(className);
+        }
+        else
+        {
+            try
+            {
+                clazz = Class.forName(className, true, getClass().getClassLoader());
+                classCache.put(className, clazz);
+            }
+            catch (Exception ex)
+            {
+                // unpossible?
+                throw Throwables.propagate(ex);
+            }
+        }
+        try
+        {
+            Field f = clazz.getField(annotationTarget);
+            itemStackHolders.add(new ItemStackHolderRef(f, value, meta, nbt));
+        }
+        catch (Exception ex)
+        {
+            // unpossible?
+            throw Throwables.propagate(ex);
+        }
+    }
+}

fml/src/main/java/net/minecraftforge/fml/common/registry/ItemStackHolderRef.java

@@ -0,0 +1,83 @@
+package net.minecraftforge.fml.common.registry;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+
+import net.minecraft.item.ItemStack;
+import net.minecraftforge.fml.common.FMLLog;
+
+import org.apache.logging.log4j.Level;
+
+import com.google.common.base.Throwables;
+
+
+
+/**
+ * Internal class used in tracking {@link ItemStackHolder} references
+ *
+ * @author cpw
+ *
+ */
+class ItemStackHolderRef {
+    private Field field;
+    private String itemName;
+    private int meta;
+    private String serializednbt;
+
+
+    ItemStackHolderRef(Field field, String itemName, int meta, String serializednbt)
+    {
+        this.field = field;
+        this.itemName = itemName;
+        this.meta = meta;
+        this.serializednbt = serializednbt;
+        makeWritable(field);
+    }
+
+    private static Field modifiersField;
+    private static Object reflectionFactory;
+    private static Method newFieldAccessor;
+    private static Method fieldAccessorSet;
+    private static void makeWritable(Field f)
+    {
+        try
+        {
+            if (modifiersField == null)
+            {
+                Method getReflectionFactory = Class.forName("sun.reflect.ReflectionFactory").getDeclaredMethod("getReflectionFactory");
+                reflectionFactory = getReflectionFactory.invoke(null);
+                newFieldAccessor = Class.forName("sun.reflect.ReflectionFactory").getDeclaredMethod("newFieldAccessor", Field.class, boolean.class);
+                fieldAccessorSet = Class.forName("sun.reflect.FieldAccessor").getDeclaredMethod("set", Object.class, Object.class);
+                modifiersField = Field.class.getDeclaredField("modifiers");
+                modifiersField.setAccessible(true);
+            }
+            modifiersField.setInt(f, f.getModifiers() & ~Modifier.FINAL);
+        } catch (Exception e)
+        {
+            throw Throwables.propagate(e);
+        }
+    }
+
+    public void apply()
+    {
+        ItemStack is;
+        try
+        {
+            is = GameRegistry.makeItemStack(itemName, meta, 1, serializednbt);
+        } catch (RuntimeException e)
+        {
+            FMLLog.getLogger().log(Level.ERROR, "Caught exception processing itemstack {},{},{} in annotation at {}.{}", itemName, meta, serializednbt,field.getClass().getName(),field.getName());
+            throw e;
+        }
+        try
+        {
+            Object fieldAccessor = newFieldAccessor.invoke(reflectionFactory, field, false);
+            fieldAccessorSet.invoke(fieldAccessor, null, is);
+        }
+        catch (Exception e)
+        {
+            FMLLog.getLogger().log(Level.WARN, "Unable to set {} with value {},{},{}", this.field, this.itemName, this.meta, this.serializednbt);
+        }
+    }
+}

fml/src/main/java/net/minecraftforge/fml/server/FMLServerHandler.java

@@ -272,4 +272,10 @@ public class FMLServerHandler implements IFMLSidedHandler
     {
         // NOOP
     }
+
+    @Override
+    public String stripSpecialChars(String message)
+    {
+        return message;
+    }
 }

patches/minecraft/net/minecraft/client/gui/FontRenderer.java.patch

@@ -17,7 +17,7 @@
                  boolean flag1 = (c0 == 0 || j == -1 || this.field_78293_l) && p_78255_2_;
  
                  if (flag1)
-@@ -583,11 +584,6 @@
+@@ -592,11 +593,6 @@
                  int j = this.field_78287_e[p_78263_1_] >>> 4;
                  int k = this.field_78287_e[p_78263_1_] & 15;
  

src/main/java/net/minecraftforge/classloading/FMLForgePlugin.java

@@ -13,7 +13,7 @@ public class FMLForgePlugin implements IFMLLoadingPlugin
     @Override
     public String[] getASMTransformerClass()
     {
-        return new String[0];
+        return new String[] { "net.minecraftforge.classloading.FluidIdTransformer" };
     }
 
     @Override

src/main/java/net/minecraftforge/classloading/FluidIdTransformer.java

@@ -0,0 +1,55 @@
+package net.minecraftforge.classloading;
+
+import java.util.ListIterator;
+
+import net.minecraft.launchwrapper.IClassTransformer;
+
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.ClassNode;
+import org.objectweb.asm.tree.FieldInsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+
+import net.minecraftforge.fml.common.FMLLog;;
+
+public class FluidIdTransformer implements IClassTransformer {
+    private static final String FLUID_TYPE = "net/minecraftforge/fluids/FluidStack";
+    private static final String GETID_NAME = "getFluidID";
+    private static final String LEGACY_FIELDNAME = "fluidID";
+    private static final String GETID_DESC = "()I";
+
+    @Override
+    public byte[] transform(String name, String transformedName, byte[] basicClass) {
+        if (basicClass == null)
+            return null;
+        ClassNode classNode = new ClassNode();
+        ClassReader classReader = new ClassReader(basicClass);
+        classReader.accept(classNode, 0);
+
+        for (MethodNode m: classNode.methods)
+        {
+            for (ListIterator<AbstractInsnNode> it = m.instructions.iterator(); it.hasNext(); )
+            {
+                AbstractInsnNode insnNode = it.next();
+                if (insnNode.getType() == AbstractInsnNode.FIELD_INSN)
+                {
+                    FieldInsnNode fi = (FieldInsnNode)insnNode;
+                    if (FLUID_TYPE.equals(fi.owner) && LEGACY_FIELDNAME.equals(fi.name) && fi.getOpcode() == Opcodes.GETFIELD)
+                    {
+                        FMLLog.fine("Method %s.%s%s: Replacing GETFIELD fluidID with INVOKEVIRTUAL getFluidID", name, m.name, m.desc);
+                        it.remove();
+                        MethodInsnNode replace = new MethodInsnNode(Opcodes.INVOKEVIRTUAL, FLUID_TYPE, GETID_NAME, GETID_DESC, false);
+                        it.add(replace);
+                    }
+                }
+            }
+        }
+        ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS);
+        classNode.accept(writer);
+        return writer.toByteArray();
+    }
+
+}

src/main/java/net/minecraftforge/common/ForgeChunkManager.java

@@ -663,7 +663,7 @@ public class ForgeChunkManager
             throw new RuntimeException("Invalid ticket request");
         }
 
-        int allowedCount = ticketConstraints.containsKey(modId) ? ticketConstraints.get(modId) : defaultMaxCount;
+        int allowedCount = getMaxTicketLengthFor(modId);
 
         if (tickets.get(world).get(modId).size() >= allowedCount)
         {

src/main/java/net/minecraftforge/common/ForgeModContainer.java

@@ -26,6 +26,7 @@ import net.minecraftforge.classloading.FMLForgePlugin;
 import net.minecraftforge.common.config.Configuration;
 import net.minecraftforge.common.config.Property;
 import net.minecraftforge.common.network.ForgeNetworkHandler;
+import net.minecraftforge.fluids.FluidRegistry;
 import net.minecraftforge.oredict.OreDictionary;
 import net.minecraftforge.oredict.RecipeSorter;
 import net.minecraftforge.server.command.ForgeCommand;
@@ -60,7 +61,6 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
     public static boolean removeErroringEntities = false;
     public static boolean removeErroringTileEntities = false;
     public static boolean disableStitchedFileSaving = false;
-    public static boolean forceDuplicateFluidBlockCrash = true;
     public static boolean fullBoundingBoxLadders = false;
     public static double zombieSummonBaseChance = 0.1;
     public static int[] blendRanges = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34 };
@@ -68,6 +68,7 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
     public static boolean shouldSortRecipies = true;
     public static boolean disableVersionCheck = false;
     public static int defaultSpawnFuzz = 20;
+    public static boolean defaultHasSpawnFuzz = true;
 
     private static Configuration config;
 
@@ -157,17 +158,6 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
         shouldSortRecipies = prop.getBoolean(shouldSortRecipies);
         propOrder.add(prop.getName());
 
-        prop = config.get(Configuration.CATEGORY_GENERAL, "forceDuplicateFluidBlockCrash", true);
-        prop.comment = "Set this to true to force a crash if more than one block attempts to link back to the same Fluid. Enabled by default.";
-        prop.setLanguageKey("forge.configgui.forceDuplicateFluidBlockCrash").setRequiresMcRestart(true);
-        forceDuplicateFluidBlockCrash = prop.getBoolean(true);
-        propOrder.add(prop.getName());
-
-        if (!forceDuplicateFluidBlockCrash)
-        {
-            FMLLog.warning("Disabling forced crashes on duplicate Fluid Blocks - USE AT YOUR OWN RISK");
-        }
-
         prop = config.get(Configuration.CATEGORY_GENERAL, "removeErroringEntities", false);
         prop.comment = "Set this to true to remove any Entity that throws an error in its update method instead of closing the server and reporting a crash log. BE WARNED THIS COULD SCREW UP EVERYTHING USE SPARINGLY WE ARE NOT RESPONSIBLE FOR DAMAGES.";
         prop.setLanguageKey("forge.configgui.removeErroringEntities").setRequiresWorldRestart(true);
@@ -225,6 +215,12 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
         defaultSpawnFuzz = prop.getInt(20);
         propOrder.add(prop.getName());
 
+        prop = config.get(Configuration.CATEGORY_GENERAL, "spawnHasFuzz", Boolean.TRUE,
+                "If the overworld has ANY spawn fuzz at all. If not, the spawn will always be the exact same location.");
+        prop.setLanguageKey("forge.configgui.hasspawnfuzz").setRequiresWorldRestart(false);
+        defaultHasSpawnFuzz = prop.getBoolean(Boolean.TRUE);
+        propOrder.add(prop.getName());
+
         config.setCategoryPropertyOrder(CATEGORY_GENERAL, propOrder);
 
         if (config.hasChanged())
@@ -280,7 +276,7 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
         MinecraftForge.EVENT_BUS.register(MinecraftForge.INTERNAL_HANDLER);
         ForgeChunkManager.captureConfig(evt.getModConfigurationDirectory());
         FMLCommonHandler.instance().bus().register(this);
-        
+
         if (!ForgeModContainer.disableVersionCheck)
         {
             ForgeVersion.startVersionCheck();
@@ -301,6 +297,7 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
         {
             RecipeSorter.sortCraftManager();
         }
+        FluidRegistry.validateFluidRegistry();
     }
 
     @Subscribe
@@ -314,6 +311,7 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
         NBTTagCompound forgeData = new NBTTagCompound();
         NBTTagCompound dimData = DimensionManager.saveDimensionDataMap();
         forgeData.setTag("DimensionData", dimData);
+        FluidRegistry.writeDefaultFluidList(forgeData);
         return forgeData;
     }
 
@@ -321,6 +319,7 @@ public class ForgeModContainer extends DummyModContainer implements WorldAccessC
     public void readData(SaveHandler handler, WorldInfo info, Map<String, NBTBase> propertyMap, NBTTagCompound tag)
     {
         DimensionManager.loadDimensionDataMap(tag.hasKey("DimensionData") ? tag.getCompoundTag("DimensionData") : null);
+        FluidRegistry.loadFluidDefaults(tag);
     }
 
     @Subscribe

src/main/java/net/minecraftforge/common/network/FluidIdRegistryMessageHandler.java

@@ -12,7 +12,7 @@ public class FluidIdRegistryMessageHandler extends SimpleChannelInboundHandler<F
     @Override
     protected void channelRead0(ChannelHandlerContext ctx, ForgeMessage.FluidIdMapMessage msg) throws Exception
     {
-        FluidRegistry.initFluidIDs(msg.fluidIds);
+        FluidRegistry.initFluidIDs(msg.fluidIds, msg.defaultFluids);
     }
     @Override
     public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception

src/main/java/net/minecraftforge/common/network/ForgeMessage.java

@@ -1,12 +1,18 @@
 package net.minecraftforge.common.network;
 
 import java.util.Map;
+import java.util.Set;
 
+import org.apache.logging.log4j.Level;
+
+import net.minecraftforge.fluids.Fluid;
 import net.minecraftforge.fluids.FluidRegistry;
 
 import com.google.common.collect.BiMap;
 import com.google.common.collect.HashBiMap;
+import com.google.common.collect.Sets;
 
+import net.minecraftforge.fml.common.FMLLog;
 import net.minecraftforge.fml.common.network.ByteBufUtils;
 import io.netty.buffer.ByteBuf;
 
@@ -16,14 +22,14 @@ public abstract class ForgeMessage {
         int dimensionId;
         /** The provider ID to register with dimension on client */
         int providerId;
-        
+
         public DimensionRegisterMessage(){}
         public DimensionRegisterMessage(int dimensionId, int providerId)
         {
             this.dimensionId = dimensionId;
             this.providerId = providerId;
         }
-        
+
         @Override
         void toBytes(ByteBuf bytes)
         {
@@ -40,17 +46,23 @@ public abstract class ForgeMessage {
     }
 
     public static class FluidIdMapMessage extends ForgeMessage {
-        BiMap<String, Integer> fluidIds = HashBiMap.create();
+        BiMap<Fluid, Integer> fluidIds = HashBiMap.create();
+        Set<String> defaultFluids = Sets.newHashSet();
         @Override
         void toBytes(ByteBuf bytes)
         {
-            Map<String, Integer> ids = FluidRegistry.getRegisteredFluidIDs();
+            Map<Fluid, Integer> ids = FluidRegistry.getRegisteredFluidIDsByFluid();
             bytes.writeInt(ids.size());
-            for (Map.Entry<String, Integer> entry : ids.entrySet())
+            for (Map.Entry<Fluid, Integer> entry : ids.entrySet())
             {
-                ByteBufUtils.writeUTF8String(bytes,entry.getKey());
+                ByteBufUtils.writeUTF8String(bytes,entry.getKey().getName());
                 bytes.writeInt(entry.getValue());
             }
+            for (Map.Entry<Fluid, Integer> entry : ids.entrySet())
+            {
+                String defaultName = FluidRegistry.getDefaultFluidName(entry.getKey());
+                ByteBufUtils.writeUTF8String(bytes, defaultName);
+            }
         }
 
         @Override
@@ -60,7 +72,21 @@ public abstract class ForgeMessage {
             for (int i = 0; i < listSize; i++) {
                 String fluidName = ByteBufUtils.readUTF8String(bytes);
                 int fluidId = bytes.readInt();
-                fluidIds.put(fluidName, fluidId);
+                fluidIds.put(FluidRegistry.getFluid(fluidName), fluidId);
+            }
+            // do we have a defaults list?
+
+            if (bytes.isReadable())
+            {
+                for (int i = 0; i < listSize; i++)
+                {
+                    defaultFluids.add(ByteBufUtils.readUTF8String(bytes));
+                }
+            }
+            else
+            {
+                FMLLog.getLogger().log(Level.INFO, "Legacy server message contains no default fluid list - there may be problems with fluids");
+                defaultFluids.clear();
             }
         }
     }

src/main/java/net/minecraftforge/fluids/BlockFluidBase.java

@@ -96,6 +96,13 @@ public abstract class BlockFluidBase extends Block implements IFluidBlock
 
     protected final String fluidName;
 
+    /**
+     * This is the fluid used in the constructor. Use this reference to configure things
+     * like icons for your block. It might not be active in the registry, so do
+     * NOT expose it.
+     */
+    protected final Fluid definedFluid;
+
     public BlockFluidBase(Fluid fluid, Material material)
     {
         super(material);
@@ -111,6 +118,7 @@ public abstract class BlockFluidBase extends Block implements IFluidBlock
         this.densityDir = fluid.density > 0 ? -1 : 1;
         fluid.setBlock(this);
 
+        this.definedFluid = fluid;
         displacements.putAll(defaultDisplacements);
         this.setDefaultState(blockState.getBaseState().withProperty(LEVEL, 0));
     }

src/main/java/net/minecraftforge/fluids/Fluid.java

@@ -66,13 +66,17 @@ public class Fluid
      *
      * Default value is approximately the real-life room temperature of water in degrees Kelvin.
      */
-    protected int temperature = 295;
+    protected int temperature = 300;
 
     /**
      * Viscosity ("thickness") of the fluid - completely arbitrary; negative values are not
      * permissible.
      *
      * Default value is approximately the real-life density of water in m/s^2 (x10^-3).
+     *
+     * Higher viscosity means that a fluid flows more slowly, like molasses.
+     * Lower viscosity means that a fluid flows more quickly, like helium.
+     *
      */
     protected int viscosity = 1000;
 
@@ -117,17 +121,10 @@ public class Fluid
         {
             this.block = block;
         }
-        else if (!ForgeModContainer.forceDuplicateFluidBlockCrash)
-        {
-            FMLLog.warning("A mod has attempted to assign Block " + block + " to the Fluid '" + fluidName + "' but this Fluid has already been linked to BlockID "
-                    + this.block + ". Configure your mods to prevent this from happening.");
-        }
         else
         {
-            FMLLog.severe("A mod has attempted to assign BlockID " + block + " to the Fluid '" + fluidName + "' but this Fluid has already been linked to BlockID "
+            FMLLog.warning("A mod has attempted to assign Block " + block + " to the Fluid '" + fluidName + "' but this Fluid has already been linked to the Block "
-                    + this.block + ". Configure your mods to prevent this from happening.");
+                    + this.block + ". You may have duplicate Fluid Blocks as a result. It *may* be possible to configure your mods to avoid this.");
-            throw new LoaderException(new RuntimeException("A mod has attempted to assign BlockID " + block + " to the Fluid '" + fluidName
-                    + "' but this Fluid has already been linked to BlockID " + this.block + ". Configure your mods to prevent this from happening."));
         }
         return this;
     }
@@ -320,19 +317,4 @@ public class Fluid
     public int getColor(World world, BlockPos pos){ return getColor(); }
     public TextureAtlasSprite getIcon(World world, BlockPos pos){ return getIcon(); }
 
-    private static Map<String, String> legacyNames = Maps.newHashMap();
-    static String convertLegacyName(String fluidName)
-    {
-        return fluidName != null && legacyNames.containsKey(fluidName) ? legacyNames.get(fluidName) : fluidName;
-    }
-
-    /**
-     * Register a legacy liquid name with the Fluids system
-     * @param legacyName The legacy name to recognize
-     * @param canonicalName The canonical fluid name it will become
-     */
-    public static void registerLegacyName(String legacyName, String canonicalName)
-    {
-        legacyNames.put(legacyName.toLowerCase(Locale.ENGLISH), canonicalName);
-    }
 }

src/main/java/net/minecraftforge/fluids/FluidContainerRegistry.java

@@ -11,6 +11,7 @@ import java.util.Set;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 
+import net.minecraftforge.fml.common.FMLLog;
 import net.minecraftforge.fml.common.eventhandler.Event;
 import net.minecraft.init.Items;
 import net.minecraft.item.Item;
@@ -20,16 +21,16 @@ import net.minecraftforge.common.MinecraftForge;
 /**
  * Register simple items that contain fluids here. Useful for buckets, bottles, and things that have
  * ID/metadata mappings.
- * 
+ *
  * For more complex items, use {@link IFluidContainerItem} instead.
- * 
+ *
  * @author King Lemming
- * 
+ *
  */
 public abstract class FluidContainerRegistry
 {
-    // Holder object that implements HashCode for an ItemStack, 
+    // Holder object that implements HashCode for an ItemStack,
-    // the local maps are not guaranteed to have the same internal generic structure, 
+    // the local maps are not guaranteed to have the same internal generic structure,
     // but the external interface for checking ItemStacks will still exist.
     private static class ContainerKey
     {
@@ -51,7 +52,7 @@ public abstract class FluidContainerRegistry
             code = 31*code + container.getItem().hashCode();
             code = 31*code + container.getItemDamage();
             if (fluid != null)
-                code = 31*code + fluid.fluidID;
+                code = 31*code + fluid.getFluid().hashCode();
             return code;
         }
         @Override
@@ -64,7 +65,7 @@ public abstract class FluidContainerRegistry
             if (fluid == null && ck.fluid != null) return false;
             if (fluid != null && ck.fluid == null) return false;
             if (fluid == null && ck.fluid == null) return true;
-            if (fluid.fluidID != ck.fluid.fluidID) return false;
+            if (fluid.getFluid() != ck.fluid.getFluid()) return false;
             return true;
         }
     }
@@ -89,7 +90,7 @@ public abstract class FluidContainerRegistry
 
     /**
      * Register a new fluid containing item.
-     * 
+     *
      * @param stack
      *            FluidStack containing the type and amount of the fluid stored in the item.
      * @param filledContainer
@@ -106,7 +107,7 @@ public abstract class FluidContainerRegistry
     /**
      * Register a new fluid containing item. The item is assumed to hold 1000 mB of fluid. Also
      * registers the Fluid if possible.
-     * 
+     *
      * @param fluid
      *            Fluid type that is stored in the item.
      * @param filledContainer
@@ -126,12 +127,12 @@ public abstract class FluidContainerRegistry
 
     /**
      * Register a new fluid containing item that does not have an empty container.
-     * 
+     *
      * @param stack
      *            FluidStack containing the type and amount of the fluid stored in the item.
      * @param filledContainer
      *            ItemStack representing the container when it is full.
-     * @return True if container was successfully registered; false if it already is.
+     * @return True if container was successfully registered; false if it already is, or an invalid parameter was passed.
      */
     public static boolean registerFluidContainer(FluidStack stack, ItemStack filledContainer)
     {
@@ -141,12 +142,12 @@ public abstract class FluidContainerRegistry
     /**
      * Register a new fluid containing item that does not have an empty container. The item is
      * assumed to hold 1000 mB of fluid. Also registers the Fluid if possible.
-     * 
+     *
      * @param fluid
      *            Fluid type that is stored in the item.
      * @param filledContainer
      *            ItemStack representing the container when it is full.
-     * @return True if container was successfully registered; false if it already is.
+     * @return True if container was successfully registered; false if it already is, or an invalid parameter was passed.
      */
     public static boolean registerFluidContainer(Fluid fluid, ItemStack filledContainer)
     {
@@ -159,17 +160,22 @@ public abstract class FluidContainerRegistry
 
     /**
      * Register a new fluid containing item.
-     * 
+     *
      * @param data
      *            See {@link FluidContainerData}.
-     * @return True if container was successfully registered; false if it already is.
+     * @return True if container was successfully registered; false if it already is, or an invalid parameter was passed.
      */
     public static boolean registerFluidContainer(FluidContainerData data)
     {
-        if (isFilledContainer(data.filledContainer))
+        if (isFilledContainer(data.filledContainer) || data.filledContainer == null)
         {
             return false;
         }
+        if (data.fluid == null || data.fluid.getFluid() == null)
+        {
+        	FMLLog.bigWarning("Invalid registration attempt for a fluid container item %s has occurred. The registration has been denied to prevent crashes. The mod responsible for the registration needs to correct this.", data.filledContainer.getItem().getUnlocalizedName(data.filledContainer));
+        	return false;
+        }
         containerFluidMap.put(new ContainerKey(data.filledContainer), data);
 
         if (data.emptyContainer != null && data.emptyContainer != NULL_EMPTYCONTAINER)
@@ -184,7 +190,7 @@ public abstract class FluidContainerRegistry
 
     /**
      * Determines the fluid type and amount inside a container.
-     * 
+     *
      * @param container
      *            The fluid container.
      * @return FluidStack representing stored fluid.
@@ -202,9 +208,9 @@ public abstract class FluidContainerRegistry
 
     /**
      * Attempts to fill an empty container with a fluid.
-     * 
+     *
      * NOTE: Returns null on fail, NOT the empty container.
-     * 
+     *
      * @param fluid
      *            FluidStack containing the type and amount of fluid to fill.
      * @param container
@@ -228,7 +234,7 @@ public abstract class FluidContainerRegistry
 
     /**
      * Attempts to empty a full container.
-     * 
+     *
      * @param container
      *            ItemStack representing the full container.
      * @return Empty container if successful, otherwise null.
@@ -251,7 +257,7 @@ public abstract class FluidContainerRegistry
 
     /**
      * Determines the capacity of a full container.
-     * 
+     *
      * @param container
      *            The full container.
      * @return The containers capacity, or 0 if the ItemStack does not represent
@@ -264,7 +270,7 @@ public abstract class FluidContainerRegistry
 
     /**
      * Determines the capacity of a container.
-     * 
+     *
      * @param fluid
      *            FluidStack containing the type of fluid the capacity should be
      *            determined for (ignored for full containers).
@@ -361,7 +367,7 @@ public abstract class FluidContainerRegistry
         public final ItemStack filledContainer;
         public final ItemStack emptyContainer;
 
-        
+
         public FluidContainerData(FluidStack stack, ItemStack filledContainer, ItemStack emptyContainer)
         {
             this(stack, filledContainer, emptyContainer, false);

src/main/java/net/minecraftforge/fluids/FluidRegistry.java

@@ -1,19 +1,31 @@
 package net.minecraftforge.fluids;
 
-import java.util.HashMap;
 import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import org.apache.logging.log4j.Level;
 
 import net.minecraft.block.Block;
 import net.minecraft.init.Blocks;
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.nbt.NBTTagList;
+import net.minecraft.nbt.NBTTagString;
 import net.minecraft.util.StatCollector;
 import net.minecraftforge.common.MinecraftForge;
 
+import com.google.common.base.Strings;
 import com.google.common.collect.BiMap;
 import com.google.common.collect.HashBiMap;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
 
+import net.minecraftforge.fml.common.FMLLog;
+import net.minecraftforge.fml.common.Loader;
+import net.minecraftforge.fml.common.ModContainer;
 import net.minecraftforge.fml.common.eventhandler.Event;
+import net.minecraftforge.fml.common.registry.RegistryDelegate;
 
 /**
  * Handles Fluid registrations. Fluids MUST be registered in order to function.
@@ -25,17 +37,23 @@ public abstract class FluidRegistry
 {
     static int maxID = 0;
 
-    static HashMap<String, Fluid> fluids = Maps.newHashMap();
+    static BiMap<String, Fluid> fluids = HashBiMap.create();
-    static BiMap<String, Integer> fluidIDs = HashBiMap.create();
+    static BiMap<Fluid, Integer> fluidIDs = HashBiMap.create();
+    static BiMap<Integer, String> fluidNames = HashBiMap.create(); //Caching this just makes some other calls faster
     static BiMap<Block, Fluid> fluidBlocks;
-    
+
+    // the globally unique fluid map - only used to associate non-defaults during world/server loading
+    static BiMap<String,Fluid> masterFluidReference = HashBiMap.create();
+    static BiMap<String,String> defaultFluidName = HashBiMap.create();
+    static Map<Fluid,FluidDelegate> delegates = Maps.newHashMap();
+
     public static final Fluid WATER = new Fluid("water") {
         @Override
         public String getLocalizedName() {
             return StatCollector.translateToLocal("tile.water.name");
         }
     }.setBlock(Blocks.water).setUnlocalizedName(Blocks.water.getUnlocalizedName());
-    
+
     public static final Fluid LAVA = new Fluid("lava") {
         @Override
         public String getLocalizedName() {
@@ -57,41 +75,109 @@ public abstract class FluidRegistry
      * Called by Forge to prepare the ID map for server -> client sync.
      * Modders, DO NOT call this.
      */
-    public static void initFluidIDs(BiMap<String, Integer> newfluidIDs)
+    public static void initFluidIDs(BiMap<Fluid, Integer> newfluidIDs, Set<String> defaultNames)
     {
         maxID = newfluidIDs.size();
         fluidIDs.clear();
         fluidIDs.putAll(newfluidIDs);
+        fluidNames.clear();
+        for (Entry<Fluid, Integer> e : fluidIDs.entrySet()) {
+            fluidNames.put(e.getValue(), e.getKey().getName());
+        }
+        loadFluidDefaults(defaultNames);
     }
 
     /**
-     * Register a new Fluid. If a fluid with the same name already exists, registration is denied.
+     * Called by forge to load default fluid IDs from the world or from server -> client for syncing
+     * DO NOT call this and expect useful behaviour.
+     */
+    private static void loadFluidDefaults(Set<String> defaultNames)
+    {
+        // If there's an empty set of default names, use the defaults as defined locally
+        if (defaultNames.isEmpty()) {
+            defaultNames.addAll(defaultFluidName.values());
+        }
+        for (String defaultName : defaultNames)
+        {
+            Fluid fluid = masterFluidReference.get(defaultName);
+            if (fluid == null) {
+                String derivedName = defaultName.split(":",2)[1];
+                String localDefault = defaultFluidName.get(derivedName);
+                if (localDefault == null) {
+                    FMLLog.getLogger().log(Level.ERROR, "The fluid {} (specified as {}) is missing from this instance - it will be removed", derivedName, defaultName);
+                    continue;
+                }
+                fluid = masterFluidReference.get(localDefault);
+                FMLLog.getLogger().log(Level.ERROR, "The fluid {} specified as default is not present - it will be reverted to default {}", defaultName, localDefault);
+            }
+            FMLLog.getLogger().log(Level.DEBUG, "The fluid {} has been selected as the default fluid for {}", defaultName, fluid.getName());
+            Fluid oldFluid = fluids.put(fluid.getName(), fluid);
+            Integer id = fluidIDs.remove(oldFluid);
+            fluidIDs.put(fluid, id);
+        }
+        fluidBlocks = null;
+        for (FluidDelegate fd : delegates.values())
+        {
+            fd.rebind();
+        }
+    }
+
+    /**
+     * Register a new Fluid. If a fluid with the same name already exists, registration the alternative fluid is tracked
+     * in case it is the default in another place
      *
      * @param fluid
      *            The fluid to register.
-     * @return True if the fluid was successfully registered; false if there is a name clash.
+     * @return True if the fluid was registered as the current default fluid, false if it was only registered as an alternative
      */
     public static boolean registerFluid(Fluid fluid)
     {
-        if (fluidIDs.containsKey(fluid.getName()))
+        masterFluidReference.put(uniqueName(fluid), fluid);
+        delegates.put(fluid, new FluidDelegate(fluid, fluid.getName()));
+        if (fluids.containsKey(fluid.getName()))
         {
             return false;
         }
         fluids.put(fluid.getName(), fluid);
-        fluidIDs.put(fluid.getName(), ++maxID);
+        maxID++;
+        fluidIDs.put(fluid, maxID);
+        fluidNames.put(maxID, fluid.getName());
+        defaultFluidName.put(fluid.getName(), uniqueName(fluid));
 
         MinecraftForge.EVENT_BUS.post(new FluidRegisterEvent(fluid.getName(), maxID));
         return true;
     }
 
+    private static String uniqueName(Fluid fluid)
+    {
+        ModContainer activeModContainer = Loader.instance().activeModContainer();
+        String activeModContainerName = activeModContainer == null ? "minecraft" : activeModContainer.getModId();
+        return activeModContainerName+":"+fluid.getName();
+    }
+
+    /**
+     * Is the supplied fluid the current default fluid for it's name
+     * @param fluid the fluid we're testing
+     * @return if the fluid is default
+     */
+    public static boolean isFluidDefault(Fluid fluid)
+    {
+        return fluids.containsValue(fluid);
+    }
+
+    /**
+     * Does the supplied fluid have an entry for it's name (whether or not the fluid itself is default)
+     * @param fluid the fluid we're testing
+     * @return if the fluid's name has a registration entry
+     */
     public static boolean isFluidRegistered(Fluid fluid)
     {
-        return fluidIDs.containsKey(fluid.getName());
+        return fluid != null && fluids.containsKey(fluid.getName());
     }
 
     public static boolean isFluidRegistered(String fluidName)
     {
-        return fluidIDs.containsKey(fluidName);
+        return fluids.containsKey(fluidName);
     }
 
     public static Fluid getFluid(String fluidName)
@@ -101,31 +187,42 @@ public abstract class FluidRegistry
 
     public static Fluid getFluid(int fluidID)
     {
-        return fluids.get(getFluidName(fluidID));
+    	return fluidIDs.inverse().get(fluidID);
     }
 
-    public static String getFluidName(int fluidID)
+    public static int getFluidID(Fluid fluid)
     {
-        return fluidIDs.inverse().get(fluidID);
+    	return fluidIDs.get(fluid);
-    }
-
-    public static String getFluidName(FluidStack stack)
-    {
-        return getFluidName(stack.fluidID);
     }
 
     public static int getFluidID(String fluidName)
     {
-        return fluidIDs.get(fluidName);
+    	return fluidIDs.get(getFluid(fluidName));
+    }
+
+    @Deprecated //Remove in 1.8.3
+    public static String getFluidName(int fluidID)
+    {
+        return fluidNames.get(fluidID);
+    }
+
+    public static String getFluidName(Fluid fluid)
+    {
+        return fluids.inverse().get(fluid);
+    }
+
+    public static String getFluidName(FluidStack stack)
+    {
+        return getFluidName(stack.getFluid());
     }
 
     public static FluidStack getFluidStack(String fluidName, int amount)
     {
-        if (!fluidIDs.containsKey(fluidName))
+        if (!fluids.containsKey(fluidName))
         {
             return null;
         }
-        return new FluidStack(getFluidID(fluidName), amount);
+        return new FluidStack(getFluid(fluidName), amount);
     }
 
     /**
@@ -139,7 +236,17 @@ public abstract class FluidRegistry
     /**
      * Returns a read-only map containing Fluid Names and their associated IDs.
      */
+    @Deprecated //Change return type to <Fluid, Integer> in 1.8.3
     public static Map<String, Integer> getRegisteredFluidIDs()
+    {
+        return ImmutableMap.copyOf(fluidNames.inverse());
+    }
+
+    /**
+     * Returns a read-only map containing Fluid IDs and their associated Fluids.
+     * In 1.8.3, this will change to just 'getRegisteredFluidIDs'
+     */
+    public static Map<Fluid, Integer> getRegisteredFluidIDsByFluid()
     {
         return ImmutableMap.copyOf(fluidIDs);
     }
@@ -160,7 +267,7 @@ public abstract class FluidRegistry
         }
         return fluidBlocks.get(block);
     }
-    
+
     public static class FluidRegisterEvent extends Event
     {
         public final String fluidName;
@@ -177,4 +284,110 @@ public abstract class FluidRegistry
     {
         return maxID;
     }
-}
+
+    public static String getDefaultFluidName(Fluid key)
+    {
+        String name = masterFluidReference.inverse().get(key);
+        if (Strings.isNullOrEmpty(name)) {
+            FMLLog.getLogger().log(Level.ERROR, "The fluid registry is corrupted. A fluid {} {} is not properly registered. The mod that registered this is broken", key.getClass().getName(), key.getName());
+            throw new IllegalStateException("The fluid registry is corrupted");
+        }
+        return name;
+    }
+
+    public static void loadFluidDefaults(NBTTagCompound tag)
+    {
+        Set<String> defaults = Sets.newHashSet();
+        if (tag.hasKey("DefaultFluidList",9))
+        {
+            FMLLog.getLogger().log(Level.DEBUG, "Loading persistent fluid defaults from world");
+            NBTTagList tl = tag.getTagList("DefaultFluidList", 8);
+            for (int i = 0; i < tl.tagCount(); i++)
+            {
+                defaults.add(tl.getStringTagAt(i));
+            }
+        }
+        else
+        {
+            FMLLog.getLogger().log(Level.DEBUG, "World is missing persistent fluid defaults - using local defaults");
+        }
+        loadFluidDefaults(defaults);
+    }
+
+    public static void writeDefaultFluidList(NBTTagCompound forgeData)
+    {
+        NBTTagList tagList = new NBTTagList();
+
+        for (Entry<String, Fluid> def : fluids.entrySet())
+        {
+            tagList.appendTag(new NBTTagString(getDefaultFluidName(def.getValue())));
+        }
+
+        forgeData.setTag("DefaultFluidList", tagList);
+    }
+
+    public static void validateFluidRegistry()
+    {
+        Set<Fluid> illegalFluids = Sets.newHashSet();
+        for (Fluid f : fluids.values())
+        {
+            if (!masterFluidReference.containsValue(f))
+            {
+                illegalFluids.add(f);
+            }
+        }
+
+        if (!illegalFluids.isEmpty())
+        {
+            FMLLog.getLogger().log(Level.FATAL, "The fluid registry is corrupted. Something has inserted a fluid without registering it");
+            FMLLog.getLogger().log(Level.FATAL, "There is {} unregistered fluids", illegalFluids.size());
+            for (Fluid f: illegalFluids)
+            {
+                FMLLog.getLogger().log(Level.FATAL, "  Fluid name : {}, type: {}", f.getName(), f.getClass().getName());
+            }
+            FMLLog.getLogger().log(Level.FATAL, "The mods that own these fluids need to register them properly");
+            throw new IllegalStateException("The fluid map contains fluids unknown to the master fluid registry");
+        }
+    }
+
+    static RegistryDelegate<Fluid> makeDelegate(Fluid fl)
+    {
+        return delegates.get(fl);
+    }
+
+
+    private static class FluidDelegate implements RegistryDelegate<Fluid>
+    {
+        private String name;
+        private Fluid fluid;
+
+        FluidDelegate(Fluid fluid, String name)
+        {
+            this.fluid = fluid;
+            this.name = name;
+        }
+
+        @Override
+        public Fluid get()
+        {
+            return fluid;
+        }
+
+        @Override
+        public String name()
+        {
+            return name;
+        }
+
+        @Override
+        public Class<Fluid> type()
+        {
+            return Fluid.class;
+        }
+
+        void rebind()
+        {
+            fluid = fluids.get(name);
+        }
+    }
+}

src/main/java/net/minecraftforge/fluids/FluidStack.java

@@ -1,10 +1,10 @@
 
 package net.minecraftforge.fluids;
 
-import java.util.Locale;
-import com.google.common.base.Strings;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
+import net.minecraftforge.fml.common.FMLLog;
+import net.minecraftforge.fml.common.registry.RegistryDelegate;
 
 /**
  * ItemStack substitute for Fluids.
@@ -18,25 +18,36 @@ import net.minecraft.nbt.NBTTagCompound;
  */
 public class FluidStack
 {
-    public int fluidID;
+    /**
+     * This field will be removed in 1.8. It may be incorrect after a world is loaded. Code should always
+     * use {@link #getFluid()} instead. That will always reflect the correct value.
+     */
+    @Deprecated
+    public final Fluid fluid;
     public int amount;
     public NBTTagCompound tag;
+    private RegistryDelegate<Fluid> fluidDelegate;
 
     public FluidStack(Fluid fluid, int amount)
     {
-        this.fluidID = fluid.getID();
+        if (fluid == null)
+        {
+            FMLLog.bigWarning("Null fluid supplied to fluidstack. Did you try and create a stack for an unregistered fluid?");
+            throw new IllegalArgumentException("Cannot create a fluidstack from a null fluid");
+        }
+        else if (!FluidRegistry.isFluidRegistered(fluid))
+        {
+            FMLLog.bigWarning("Failed attempt to create a FluidStack for an unregistered Fluid %s (type %s)", fluid.getName(), fluid.getClass().getName());
+            throw new IllegalArgumentException("Cannot create a fluidstack from an unregistered fluid");
+        }
+    	this.fluidDelegate = FluidRegistry.makeDelegate(fluid);
         this.amount = amount;
+        this.fluid = fluid;
     }
 
-    public FluidStack(int fluidID, int amount)
+    public FluidStack(Fluid fluid, int amount, NBTTagCompound nbt)
     {
-        this.fluidID = fluidID;
+        this(fluid, amount);
-        this.amount = amount;
-    }
-
-    public FluidStack(int fluidID, int amount, NBTTagCompound nbt)
-    {
-        this(fluidID, amount);
 
         if (nbt != null)
         {
@@ -46,7 +57,21 @@ public class FluidStack
 
     public FluidStack(FluidStack stack, int amount)
     {
-        this(stack.fluidID, amount, stack.tag);
+        this(stack.getFluid(), amount, stack.tag);
+    }
+
+    // To be removed in 1.8
+    @Deprecated
+    public FluidStack(int fluidID, int amount)
+    {
+    	this(FluidRegistry.getFluid(fluidID), amount);
+    }
+
+    // To be removed in 1.8
+    @Deprecated
+    public FluidStack(int fluidID, int amount, NBTTagCompound nbt)
+    {
+    	this(FluidRegistry.getFluid(fluidID), amount, nbt);
     }
 
     /**
@@ -60,32 +85,23 @@ public class FluidStack
             return null;
         }
         String fluidName = nbt.getString("FluidName");
-        if (Strings.isNullOrEmpty(fluidName))
-        {
-            fluidName = nbt.hasKey("LiquidName") ? nbt.getString("LiquidName").toLowerCase(Locale.ENGLISH) : null;
-            fluidName = Fluid.convertLegacyName(fluidName);
-        }
 
-        if (fluidName ==null || FluidRegistry.getFluid(fluidName) == null)
+        if (fluidName == null || FluidRegistry.getFluid(fluidName) == null)
         {
             return null;
         }
-        FluidStack stack = new FluidStack(FluidRegistry.getFluidID(fluidName), nbt.getInteger("Amount"));
+        FluidStack stack = new FluidStack(FluidRegistry.getFluid(fluidName), nbt.getInteger("Amount"));
 
         if (nbt.hasKey("Tag"))
         {
             stack.tag = nbt.getCompoundTag("Tag");
         }
-        else if (nbt.hasKey("extra"))
-        {
-            stack.tag = nbt.getCompoundTag("extra");
-        }
         return stack;
     }
 
     public NBTTagCompound writeToNBT(NBTTagCompound nbt)
     {
-        nbt.setString("FluidName", FluidRegistry.getFluidName(fluidID));
+        nbt.setString("FluidName", FluidRegistry.getFluidName(getFluid()));
         nbt.setInteger("Amount", amount);
 
         if (tag != null)
@@ -97,7 +113,12 @@ public class FluidStack
 
     public final Fluid getFluid()
     {
-        return FluidRegistry.getFluid(fluidID);
+        return fluidDelegate.get();
+    }
+
+    public final int getFluidID()
+    {
+    	return FluidRegistry.getFluidID(getFluid());
     }
 
     public String getLocalizedName()
@@ -115,7 +136,7 @@ public class FluidStack
      */
     public FluidStack copy()
     {
-        return new FluidStack(fluidID, amount, tag);
+        return new FluidStack(getFluid(), amount, tag);
     }
 
     /**
@@ -127,7 +148,7 @@ public class FluidStack
      */
     public boolean isFluidEqual(FluidStack other)
     {
-        return other != null && fluidID == other.fluidID && isFluidStackTagEqual(other);
+        return other != null && getFluid() == other.getFluid() && isFluidStackTagEqual(other);
     }
 
     private boolean isFluidStackTagEqual(FluidStack other)
@@ -192,7 +213,12 @@ public class FluidStack
     @Override
     public final int hashCode()
     {
-        return fluidID;
+    	int code = 1;
+    	code = 31*code + getFluid().hashCode();
+    	code = 31*code + amount;
+    	if (tag != null)
+    		code = 31*code + tag.hashCode();
+    	return code;
     }
 
     /**