src/main/java/StevenDimDoors/mod_pocketDim/EventHookContainer.java

@@ -8,6 +8,7 @@ import net.minecraft.item.ItemDoor;
 import net.minecraft.item.ItemStack;
 import net.minecraft.world.World;
 import net.minecraft.world.WorldProvider;
+import net.minecraft.world.chunk.Chunk;
 import net.minecraftforge.client.event.sound.PlayBackgroundMusicEvent;
 import net.minecraftforge.client.event.sound.SoundLoadEvent;
 import net.minecraftforge.event.EventPriority;
@@ -17,12 +18,16 @@ import net.minecraftforge.event.entity.living.LivingFallEvent;
 import net.minecraftforge.event.entity.player.PlayerInteractEvent;
 import net.minecraftforge.event.entity.player.PlayerInteractEvent.Action;
 import net.minecraftforge.event.terraingen.InitMapGenEvent;
+import net.minecraftforge.event.world.ChunkEvent;
 import net.minecraftforge.event.world.WorldEvent;
 import StevenDimDoors.mod_pocketDim.config.DDProperties;
 import StevenDimDoors.mod_pocketDim.config.DDWorldProperties;
 import StevenDimDoors.mod_pocketDim.core.DDTeleporter;
+import StevenDimDoors.mod_pocketDim.core.DimLink;
+import StevenDimDoors.mod_pocketDim.core.NewDimData;
 import StevenDimDoors.mod_pocketDim.core.PocketManager;
 import StevenDimDoors.mod_pocketDim.items.BaseItemDoor;
+import StevenDimDoors.mod_pocketDim.ticking.RiftRegenerator;
 import StevenDimDoors.mod_pocketDim.util.Point4D;
 import StevenDimDoors.mod_pocketDim.world.LimboProvider;
 import StevenDimDoors.mod_pocketDim.world.PocketProvider;
@@ -36,18 +41,20 @@ public class EventHookContainer
 	
 	private final DDProperties properties;
 	private DDWorldProperties worldProperties;
+	private RiftRegenerator regenerator;
 
 	public EventHookContainer(DDProperties properties)
 	{
 		this.properties = properties;
 	}
 	
-	public void setWorldProperties(DDWorldProperties worldProperties)
+	public void setSessionFields(DDWorldProperties worldProperties, RiftRegenerator regenerator)
 	{
 		// SenseiKiwi:
-		// Why have a setter rather than accessing mod_pocketDim.worldProperties?
+		// Why have a setter rather than accessing mod_pocketDim directly?
 		// I want to make this dependency explicit in our code.
 		this.worldProperties = worldProperties;
+		this.regenerator = regenerator;
 	}
 
 	@ForgeSubscribe(priority = EventPriority.LOW)
@@ -218,6 +225,22 @@ public class EventHookContainer
 		}
 	}
 	
+	@ForgeSubscribe
+	public void onChunkLoad(ChunkEvent.Load event)
+	{
+		// Schedule rift regeneration for any links located in this chunk.
+		// This event runs on both the client and server. Allow server only.
+		Chunk chunk = event.getChunk();
+		if (!chunk.worldObj.isRemote)
+		{
+			NewDimData dimension = PocketManager.getDimensionData(chunk.worldObj);
+			for (DimLink link : dimension.getChunkLinks(chunk.xPosition, chunk.zPosition))
+			{
+				regenerator.scheduleSlowRegeneration(link);
+			}
+		}
+	}
+
 	public void playMusicForDim(World world)
 	{
 		if (world.isRemote)

src/main/java/StevenDimDoors/mod_pocketDim/blocks/BlockRift.java

@@ -7,6 +7,7 @@ import java.util.Queue;
 import java.util.Random;
 
 import net.minecraft.block.Block;
+import net.minecraft.block.BlockContainer;
 import net.minecraft.block.BlockFlowing;
 import net.minecraft.block.BlockFluid;
 import net.minecraft.block.ITileEntityProvider;
@@ -47,25 +48,27 @@ public class BlockRift extends Block implements ITileEntityProvider
 	public static final int MAX_WORLD_THREAD_DROP_CHANCE = 1000;
 	
 	private final DDProperties properties;
-	private final ArrayList<Integer> blocksImmuneToRift;
+	private final ArrayList<Integer> blocksImmuneToRift;	// List of Vanilla blocks immune to rifts
+	private final ArrayList<Integer> modBlocksImmuneToRift; // List of DD blocks immune to rifts
 	
 	public BlockRift(int i, int j, Material par2Material, DDProperties properties) 
 	{
 		super(i, par2Material);
 		this.setTickRandomly(true);
 		this.properties = properties;
-		this.blocksImmuneToRift = new ArrayList<Integer>();
-		this.blocksImmuneToRift.add(properties.FabricBlockID);
-		this.blocksImmuneToRift.add(properties.PermaFabricBlockID);
-		this.blocksImmuneToRift.add(properties.DimensionalDoorID);
-		this.blocksImmuneToRift.add(properties.WarpDoorID);
-		this.blocksImmuneToRift.add(properties.TransTrapdoorID);
-		this.blocksImmuneToRift.add(properties.UnstableDoorID);
-		this.blocksImmuneToRift.add(properties.RiftBlockID);
-		this.blocksImmuneToRift.add(properties.TransientDoorID);
-		this.blocksImmuneToRift.add(properties.GoldenDimensionalDoorID);
-		this.blocksImmuneToRift.add(properties.GoldenDoorID);
+		this.modBlocksImmuneToRift = new ArrayList<Integer>();
+		this.modBlocksImmuneToRift.add(properties.FabricBlockID);
+		this.modBlocksImmuneToRift.add(properties.PermaFabricBlockID);
+		this.modBlocksImmuneToRift.add(properties.DimensionalDoorID);
+		this.modBlocksImmuneToRift.add(properties.WarpDoorID);
+		this.modBlocksImmuneToRift.add(properties.TransTrapdoorID);
+		this.modBlocksImmuneToRift.add(properties.UnstableDoorID);
+		this.modBlocksImmuneToRift.add(properties.RiftBlockID);
+		this.modBlocksImmuneToRift.add(properties.TransientDoorID);
+		this.modBlocksImmuneToRift.add(properties.GoldenDimensionalDoorID);
+		this.modBlocksImmuneToRift.add(properties.GoldenDoorID);
 		
+		this.blocksImmuneToRift = new ArrayList<Integer>();
 		this.blocksImmuneToRift.add(Block.blockLapis.blockID);
 		this.blocksImmuneToRift.add(Block.blockIron.blockID);
 		this.blocksImmuneToRift.add(Block.blockGold.blockID);
@@ -220,7 +223,7 @@ public class BlockRift extends Block implements ITileEntityProvider
 		return targets;
 	}
 		
-	private void dropWorldThread(int blockID, World world, int x, int y, int z, Random random)
+	public void dropWorldThread(int blockID, World world, int x, int y, int z, Random random)
 	{
 		if (blockID != 0 && (random.nextInt(MAX_WORLD_THREAD_DROP_CHANCE) < properties.WorldThreadDropChance)
 				&& !(Block.blocksList[blockID] instanceof BlockFlowing ||
@@ -252,16 +255,6 @@ public class BlockRift extends Block implements ITileEntityProvider
 		}
 	}
 	
-	public void regenerateRift(World world, int x, int y, int z, Random random)
-	{
-		if (!this.isBlockImmune(world, x, y, z) && world.getChunkProvider().chunkExists(x >> 4, z >> 4))
-		{
-			int blockID = world.getBlockId(x, y, z);
-			if (world.setBlock(x, y, z, properties.RiftBlockID))
-				dropWorldThread(blockID, world, x, y, z, random);
-		}
-	}
-	
 	public boolean spreadRift(NewDimData dimension, DimLink parent, World world, Random random)
 	{
 		int x, y, z, blockID;
@@ -413,6 +406,15 @@ public class BlockRift extends Block implements ITileEntityProvider
 		}
 	}
 	
+	public boolean tryPlacingRift(World world, int x, int y, int z)
+	{
+		if (world != null && !isBlockImmune(world, x, y, z))
+		{
+			return world.setBlock(x, y, z, mod_pocketDim.blockRift.blockID);
+		}
+		return false;
+	}
+
 	public boolean isBlockImmune(World world, int x, int y, int z)
 	{
 		Block block = Block.blocksList[world.getBlockId(x, y, z)];
@@ -424,7 +426,21 @@ public class BlockRift extends Block implements ITileEntityProvider
 			// is designed to receive an entity, the source of the blast. We have no entity so
 			// I've set this to access blockResistance directly. Might need changing later.
 			
-			return (block.blockResistance >= MIN_IMMUNE_RESISTANCE || blocksImmuneToRift.contains(block.blockID));
+			return (block.blockResistance >= MIN_IMMUNE_RESISTANCE ||
+					modBlocksImmuneToRift.contains(block.blockID) ||
+					blocksImmuneToRift.contains(block.blockID));
+		}
+		return false;
+	}
+	
+	public boolean isModBlockImmune(World world, int x, int y, int z)
+	{
+		// Check whether the block at the specified location is one of the
+		// rift-resistant blocks from DD.
+		Block block = Block.blocksList[world.getBlockId(x, y, z)];
+		if (block != null)
+		{
+			return modBlocksImmuneToRift.contains(block.blockID);
 		}
 		return false;
 	}

src/main/java/StevenDimDoors/mod_pocketDim/items/ItemRiftSignature.java

@@ -71,7 +71,8 @@ public class ItemRiftSignature extends Item
 		int orientation = MathHelper.floor_double(((player.rotationYaw + 180.0F) * 4.0F / 360.0F) - 0.5D) & 3;
 		if (source != null)
 		{
-			//The link was used before and already has an endpoint stored. Create links connecting the two endpoints.
+			// The link was used before and already has an endpoint stored.
+			// Create links connecting the two endpoints.
 			NewDimData sourceDimension = PocketManager.getDimensionData(source.getDimension());
 			NewDimData destinationDimension = PocketManager.getDimensionData(world);
 			DimLink link = sourceDimension.createLink(source.getX(), source.getY(), source.getZ(), LinkTypes.NORMAL,source.getOrientation());
@@ -79,27 +80,21 @@ public class ItemRiftSignature extends Item
 			destinationDimension.setLinkDestination(link, x, adjustedY, z);
 			sourceDimension.setLinkDestination(reverse, source.getX(), source.getY(), source.getZ());
 
-			//Try placing a rift at the destination point
-			if (!mod_pocketDim.blockRift.isBlockImmune(world, x, adjustedY, z))
-			{
-				world.setBlock(x, adjustedY, z, mod_pocketDim.blockRift.blockID);
-			}
+			// Try placing a rift at the destination point
+			mod_pocketDim.blockRift.tryPlacingRift(world, x, adjustedY, z);
 
-			//Try placing a rift at the source point, but check if its world is loaded first
+			// Try placing a rift at the source point
+			// We don't need to check if sourceWorld is null - that's already handled.
 			World sourceWorld = DimensionManager.getWorld(sourceDimension.id());
-			if (sourceWorld != null &&
-				!mod_pocketDim.blockRift.isBlockImmune(sourceWorld, source.getX(), source.getY(), source.getZ()))
-			{
-				sourceWorld.setBlock(source.getX(), source.getY(), source.getZ(), mod_pocketDim.blockRift.blockID);
-			}
+			mod_pocketDim.blockRift.tryPlacingRift(sourceWorld, source.getX(), source.getY(), source.getZ());
 
 			if (!player.capabilities.isCreativeMode)
 			{
 				stack.stackSize--;
 			}
 			clearSource(stack);
-			mod_pocketDim.sendChat(player,("Rift Created"));
-			world.playSoundAtEntity(player,mod_pocketDim.modid+":riftEnd", 0.6f, 1);
+			mod_pocketDim.sendChat(player, "Rift Created");
+			world.playSoundAtEntity(player, mod_pocketDim.modid + ":riftEnd", 0.6f, 1);
 		}
 		else
 		{

src/main/java/StevenDimDoors/mod_pocketDim/items/ItemStabilizedRiftSignature.java

@@ -90,19 +90,13 @@ public class ItemStabilizedRiftSignature extends ItemRiftSignature
 				sourceDimension.setLinkDestination(reverse, source.getX(), source.getY(), source.getZ());
 	
 				// Try placing a rift at the destination point
-				if (!mod_pocketDim.blockRift.isBlockImmune(world, x, adjustedY, z))
-				{
-					world.setBlock(x, adjustedY, z, mod_pocketDim.blockRift.blockID);
-				}
+				mod_pocketDim.blockRift.tryPlacingRift(world, x, adjustedY, z);
 			}
 			
-			// Try placing a rift at the source point, but check if its world is loaded first
+			// Try placing a rift at the source point
+			// We don't need to check if sourceWorld is null - that's already handled.
 			World sourceWorld = DimensionManager.getWorld(sourceDimension.id());
-			if (sourceWorld != null &&
-				!mod_pocketDim.blockRift.isBlockImmune(sourceWorld, source.getX(), source.getY(), source.getZ()))
-			{
-				sourceWorld.setBlock(source.getX(), source.getY(), source.getZ(), mod_pocketDim.blockRift.blockID);
-			}
+			mod_pocketDim.blockRift.tryPlacingRift(sourceWorld, source.getX(), source.getY(), source.getZ());
 			
 			mod_pocketDim.sendChat(player, "Rift Created");
 			world.playSoundAtEntity(player, "mods.DimDoors.sfx.riftEnd", 0.6f, 1);
@@ -111,8 +105,8 @@ public class ItemStabilizedRiftSignature extends ItemRiftSignature
 		{
 			// The link signature has not been used. Store its current target as the first location. 
 			setSource(stack, x, adjustedY, z, orientation, PocketManager.getDimensionData(world));
-			mod_pocketDim.sendChat(player,"Location Stored in Stabilized Rift Signature");
-			world.playSoundAtEntity(player,"mods.DimDoors.sfx.riftStart", 0.6f, 1);
+			mod_pocketDim.sendChat(player, "Location Stored in Stabilized Rift Signature");
+			world.playSoundAtEntity(player, "mods.DimDoors.sfx.riftStart", 0.6f, 1);
 		}
 		return true;
 	}
@@ -149,13 +143,10 @@ public class ItemStabilizedRiftSignature extends ItemRiftSignature
 				link = sourceDimension.createLink(source.getX(), source.getY(), source.getZ(), LinkTypes.NORMAL, source.getOrientation());
 				destinationDimension.setLinkDestination(link, x, adjustedY, z);
 				
-				// Try placing a rift at the source point, but check if its world is loaded first
+				// Try placing a rift at the source point
+				// We don't need to check if sourceWorld is null - that's already handled.
 				World sourceWorld = DimensionManager.getWorld(sourceDimension.id());
-				if (sourceWorld != null &&
-					!mod_pocketDim.blockRift.isBlockImmune(sourceWorld, source.getX(), source.getY(), source.getZ()))
-				{
-					sourceWorld.setBlock(source.getX(), source.getY(), source.getZ(), mod_pocketDim.blockRift.blockID);
-				}
+				mod_pocketDim.blockRift.tryPlacingRift(sourceWorld, source.getX(), source.getY(), source.getZ());
 				
 				// This call doesn't seem to be working...
 				world.playSoundEffect(x + 0.5, adjustedY + 0.5, z + 0.5, "mods.DimDoors.sfx.riftEnd", 0.6f, 1);

src/main/java/StevenDimDoors/mod_pocketDim/mod_pocketDim.java

@@ -53,7 +53,6 @@ import StevenDimDoors.mod_pocketDim.items.ItemWarpDoor;
 import StevenDimDoors.mod_pocketDim.items.ItemWorldThread;
 import StevenDimDoors.mod_pocketDim.items.itemRiftRemover;
 import StevenDimDoors.mod_pocketDim.ticking.CustomLimboPopulator;
-import StevenDimDoors.mod_pocketDim.ticking.FastRiftRegenerator;
 import StevenDimDoors.mod_pocketDim.ticking.LimboDecayScheduler;
 import StevenDimDoors.mod_pocketDim.ticking.MobMonolith;
 import StevenDimDoors.mod_pocketDim.ticking.RiftRegenerator;
@@ -143,8 +142,7 @@ public class mod_pocketDim
 	public static DDProperties properties;
 	public static DDWorldProperties worldProperties;
 	public static CustomLimboPopulator spawner; //Added this field temporarily. Will be refactored out later.
-	private static RiftRegenerator riftRegenerator;
-	public static FastRiftRegenerator fastRiftRegenerator;
+	public static RiftRegenerator riftRegenerator;
 	public static GatewayGenerator gatewayGenerator;
 	public static DeathTracker deathTracker;
 	private static ServerTickHandler serverTickHandler;
@@ -325,6 +323,9 @@ public class mod_pocketDim
 			// Unregister all tick receivers from serverTickHandler to avoid leaking
 			// scheduled tasks between single-player game sessions
 			serverTickHandler.unregisterReceivers();
+			spawner = null;
+			riftRegenerator = null;
+			limboDecayScheduler = null;
 		}
 		catch (Exception e)
 		{
@@ -339,7 +340,6 @@ public class mod_pocketDim
 		
 		// Load the config file that's specific to this world
 		worldProperties = new DDWorldProperties(new File(currrentSaveRootDirectory + "/DimensionalDoors/DimDoorsWorld.cfg"));
-		hooks.setWorldProperties(worldProperties);
 		
 		// Initialize a new DeathTracker
 		deathTracker = new DeathTracker(currrentSaveRootDirectory + "/DimensionalDoors/data/deaths.txt");
@@ -347,9 +347,10 @@ public class mod_pocketDim
 		// Register regular tick receivers
 		// CustomLimboPopulator should be initialized before any provider instances are created
 		spawner = new CustomLimboPopulator(serverTickHandler, properties);
-		riftRegenerator = new RiftRegenerator(serverTickHandler);
+		riftRegenerator = new RiftRegenerator(serverTickHandler, blockRift);
 		limboDecayScheduler = new LimboDecayScheduler(serverTickHandler, limboDecay);
-		fastRiftRegenerator = new FastRiftRegenerator(serverTickHandler);
+		
+		hooks.setSessionFields(worldProperties, riftRegenerator);
 	}
 
 	@EventHandler

src/main/java/StevenDimDoors/mod_pocketDim/ticking/FastRiftRegenerator.java

@@ -1,54 +0,0 @@
-package StevenDimDoors.mod_pocketDim.ticking;
-
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Random;
-
-import net.minecraft.world.World;
-import net.minecraftforge.common.DimensionManager;
-import StevenDimDoors.mod_pocketDim.mod_pocketDim;
-import StevenDimDoors.mod_pocketDim.core.PocketManager;
-import StevenDimDoors.mod_pocketDim.util.Point4D;
-
-public class FastRiftRegenerator implements IRegularTickReceiver {
-	
-	private static final int RIFT_REGENERATION_INTERVAL = 10; //Regenerate scheduled rifts every 10 ticks
-	private static Random random = new Random();
-
-	private ArrayList<Point4D> locationsToRegen = new ArrayList<Point4D>();
-	
-	public FastRiftRegenerator(IRegularTickSender sender)
-	{
-		sender.registerReceiver(this, RIFT_REGENERATION_INTERVAL, false);
-	}
-	
-	@Override
-	public void notifyTick()
-	{
-		regenerateScheduledRifts();
-	}
-	
-	public void regenerateScheduledRifts()
-	{
-		if (!locationsToRegen.isEmpty())
-		{
-			@SuppressWarnings("cast")
-			List<Integer> loadedWorlds = (List<Integer>) Arrays.asList(DimensionManager.getIDs());
-			for (Point4D point: locationsToRegen)
-			{
-				if (loadedWorlds.contains(point.getDimension()) && PocketManager.getLink(point) != null)
-				{
-		    		World world = DimensionManager.getWorld(point.getDimension());
-	    			mod_pocketDim.blockRift.regenerateRift(world, point.getX(), point.getY(), point.getZ(), random);
-				}
-			}
-			locationsToRegen.clear();
-		}
-	}
-	
-	public void registerRiftForRegen(int x, int y, int z, int dimID)
-	{
-		this.locationsToRegen.add(new Point4D(x, y, z, dimID));
-	}
-}

src/main/java/StevenDimDoors/mod_pocketDim/ticking/RiftRegenerator.java

@@ -1,56 +1,113 @@
 package StevenDimDoors.mod_pocketDim.ticking;
 
-import java.util.Arrays;
-import java.util.List;
+import java.util.PriorityQueue;
 import java.util.Random;
 
+import net.minecraft.util.MathHelper;
 import net.minecraft.world.World;
 import net.minecraftforge.common.DimensionManager;
-import StevenDimDoors.mod_pocketDim.mod_pocketDim;
+import StevenDimDoors.mod_pocketDim.blocks.BlockRift;
 import StevenDimDoors.mod_pocketDim.core.DimLink;
-import StevenDimDoors.mod_pocketDim.core.NewDimData;
 import StevenDimDoors.mod_pocketDim.core.PocketManager;
 import StevenDimDoors.mod_pocketDim.util.Point4D;
 
 public class RiftRegenerator implements IRegularTickReceiver {
 	
-	private static final int RIFT_REGENERATION_INTERVAL = 200; //Regenerate random rifts every 200 ticks
-	private static final int RIFTS_REGENERATED_PER_DIMENSION = 5;
+	// Ranges of regeneration delays, in seconds
+	private static final int MIN_FAST_DELAY = 1;
+	private static final int MAX_FAST_DELAY = 3;
+	private static final int MIN_SLOW_DELAY = 5;
+	private static final int MAX_SLOW_DELAY = 15;
+	private static final int MIN_RESCHEDULE_DELAY = 4 * 60;
+	private static final int MAX_RESCHEDULE_DELAY = 6 * 60;
+	
+	private static final int TICKS_PER_SECOND = 20;
+	private static final int RIFT_REGENERATION_INTERVAL = 1; // Check the regeneration queue every tick
 	private static Random random = new Random();
 	
-	public RiftRegenerator(IRegularTickSender sender)
+	private long tickCount = 0;
+	private PriorityQueue<RiftTicket> ticketQueue;
+	private BlockRift blockRift;
+	
+	public RiftRegenerator(IRegularTickSender sender, BlockRift blockRift)
 	{
+		this.ticketQueue = new PriorityQueue<RiftTicket>();
+		this.blockRift = blockRift;
 		sender.registerReceiver(this, RIFT_REGENERATION_INTERVAL, false);
 	}
 	
 	@Override
 	public void notifyTick()
 	{
-		regenerateRiftsInLoadedWorlds();
+		processTicketQueue();
+		tickCount++;
 	}
 	
-	private static void regenerateRiftsInLoadedWorlds()
+	public void scheduleSlowRegeneration(DimLink link)
 	{
-		// Regenerate rifts that have been replaced (not permanently removed) by players
-		// Only do this in dimensions that are currently loaded
-		List<Integer> loadedWorlds = Arrays.asList(DimensionManager.getIDs());
-		for (Integer dimensionID : loadedWorlds)
-    	{
-			NewDimData dimension = PocketManager.getDimensionData(dimensionID);
-			if (dimension.linkCount() > 0)
-			{
-	    		World world = DimensionManager.getWorld(dimension.id());
+		scheduleRegeneration(link, MIN_SLOW_DELAY, MAX_SLOW_DELAY);
+	}
 	
-	    		if (world != null)
+	public void scheduleFastRegeneration(DimLink link)
 	{
-	    			for (int count = 0; count < RIFTS_REGENERATED_PER_DIMENSION; count++)
+		scheduleRegeneration(link, MIN_FAST_DELAY, MAX_FAST_DELAY);
+	}
+	
+	private void scheduleRegeneration(DimLink link, int minDelay, int maxDelay)
 	{
-						DimLink link = dimension.getRandomLink();
-	    				Point4D source = link.source();
-	    				mod_pocketDim.blockRift.regenerateRift(world, source.getX(), source.getY(), source.getZ(), random);
-	    			}
+		int tickDelay = MathHelper.getRandomIntegerInRange(random, minDelay * TICKS_PER_SECOND, maxDelay * TICKS_PER_SECOND);
+		ticketQueue.add(new RiftTicket(link.source(), tickCount + tickDelay));
+	}
+	
+	private void processTicketQueue()
+	{
+		RiftTicket ticket;
+		while (!ticketQueue.isEmpty() && ticketQueue.peek().timestamp() <= tickCount)
+		{
+			ticket = ticketQueue.remove();
+			regenerateRift(ticket.location());
 		}
 	}
+
+	private void regenerateRift(Point4D location)
+	{
+		int x = location.getX();
+		int y = location.getY();
+		int z = location.getZ();
+		
+		// Try to regenerate a rift, or possibly reschedule its regeneration.
+		// The world for the given location must be loaded.
+		World world = DimensionManager.getWorld(location.getDimension());
+		if (world == null)
+			return;
+		
+		// There must be a link at the given location.
+		DimLink link = PocketManager.getLink(location);
+		if (link == null)
+			return;
+		
+		// The chunk at the given location must be loaded.
+		// FIXME: I can't figure out how to check if a chunk is loaded.
+		// Will only check if the chunk exists for now. This isn't a big deal. --SenseiKiwi
+		if (!world.getChunkProvider().chunkExists(x >> 4, z >> 4))
+			return;
+		
+		// If the location is occupied by an immune DD block, then don't regenerate.
+		if (blockRift.isModBlockImmune(world, x, y, z))
+			return;
+		
+		// If the location is occupied by an immune block, then reschedule.
+		if (blockRift.isBlockImmune(world, x, y, z))
+		{
+			scheduleRegeneration(link, MIN_RESCHEDULE_DELAY, MAX_RESCHEDULE_DELAY);
+		}
+		else
+		{
+			// All of the necessary conditions have been met. Restore the rift!
+			int blockID = world.getBlockId(x, y, z);
+			if (world.setBlock(x, y, z, blockRift.blockID))
+				blockRift.dropWorldThread(blockID, world, x, y, z, random);
 		}
 	}
+	
 }

src/main/java/StevenDimDoors/mod_pocketDim/ticking/RiftTicket.java

@@ -0,0 +1,40 @@
+package StevenDimDoors.mod_pocketDim.ticking;
+
+import StevenDimDoors.mod_pocketDim.util.Point4D;
+
+public class RiftTicket implements Comparable<RiftTicket> {
+
+	private long timestamp;
+	private Point4D location;
+	
+	public RiftTicket(Point4D location, long timestamp)
+	{
+		this.timestamp = timestamp;
+		this.location = location;
+	}
+	
+	@Override
+	public int compareTo(RiftTicket other)
+	{
+		if (this.timestamp < other.timestamp)
+		{
+			return -1;
+		}
+		else if (this.timestamp > other.timestamp)
+		{
+			return 1;
+		}
+		return 0;
+	}
+	
+	public long timestamp()
+	{
+		return timestamp;
+	}
+	
+	public Point4D location()
+	{
+		return location;
+	}
+	
+}

src/main/java/StevenDimDoors/mod_pocketDim/tileentities/TileEntityDimDoor.java

@@ -1,17 +1,13 @@
 package StevenDimDoors.mod_pocketDim.tileentities;
 
 import java.util.Random;
-import StevenDimDoors.mod_pocketDim.ServerPacketHandler;
-import StevenDimDoors.mod_pocketDim.mod_pocketDim;
-import StevenDimDoors.mod_pocketDim.blocks.IDimDoor;
-import StevenDimDoors.mod_pocketDim.core.NewDimData;
-import StevenDimDoors.mod_pocketDim.core.PocketManager;
-import net.minecraft.block.Block;
+
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.network.packet.Packet;
-import net.minecraft.network.packet.Packet130UpdateSign;
-import net.minecraft.network.packet.Packet250CustomPayload;
-import net.minecraft.tileentity.TileEntity;
+import StevenDimDoors.mod_pocketDim.ServerPacketHandler;
+import StevenDimDoors.mod_pocketDim.mod_pocketDim;
+import StevenDimDoors.mod_pocketDim.core.DimLink;
+import StevenDimDoors.mod_pocketDim.core.PocketManager;
 
 public class TileEntityDimDoor extends DDTileEntityBase 
 {
@@ -30,9 +26,10 @@ public class TileEntityDimDoor extends DDTileEntityBase
 	@Override
 	public Packet getDescriptionPacket()
 	{
-		 if(PocketManager.getLink(xCoord, yCoord, zCoord, worldObj)!=null)
+		DimLink link = PocketManager.getLink(xCoord, yCoord, zCoord, worldObj);
+		if (link != null)
 		{
-			 return ServerPacketHandler.createLinkPacket(PocketManager.getLink(xCoord, yCoord, zCoord, worldObj).link());
+			return ServerPacketHandler.createLinkPacket(link.link());
 		}
 		return null;
 	}
@@ -40,13 +37,13 @@ public class TileEntityDimDoor extends DDTileEntityBase
 	@Override
 	public void invalidate()
 	{
-		this.tileEntityInvalid = true;
-
-		if(this.worldObj.getBlockId(xCoord, yCoord, zCoord)==0&&!this.worldObj.isRemote)
+		super.invalidate();
+		if (!worldObj.isRemote && worldObj.getBlockId(xCoord, yCoord, zCoord) == 0)
 		{
-			if(PocketManager.getLink(xCoord, yCoord, zCoord, worldObj)!=null)
+			DimLink link = PocketManager.getLink(xCoord, yCoord, zCoord, worldObj);
+			if (link != null)
 			{
-				mod_pocketDim.fastRiftRegenerator.registerRiftForRegen(xCoord, yCoord, zCoord, this.worldObj.provider.dimensionId);	 
+				 mod_pocketDim.riftRegenerator.scheduleFastRegeneration(link);
 			}
 		}
 	}