2 files changed, 131 insertions, 14 deletions

diff --git a/src/main/java/gregtech/api/GregTech_API.java b/src/main/java/gregtech/api/GregTech_API.java
index dac494d9bc..c7d02c7bed 100644
--- a/src/main/java/gregtech/api/GregTech_API.java
+++ b/src/main/java/gregtech/api/GregTech_API.java
@@ -389,9 +389,15 @@ public class GregTech_API {
      * @param aZ     is the Z-Coord of the update causing Block
      */
     public static boolean causeMachineUpdate(World aWorld, int aX, int aY, int aZ) {
-        if (!aWorld.isRemote)
-            new Thread(new GT_Runnable_MachineBlockUpdate(aWorld, aX, aY, aZ), "Machine Block Updating").start();
-        return true;
+        if (!aWorld.isRemote && !GT_Runnable_MachineBlockUpdate.getINSTANCETHREAD().isAlive()) {
+            GT_Runnable_MachineBlockUpdate.setMachineUpdateValues(aWorld, aX, aY, aZ);
+            GT_Runnable_MachineBlockUpdate.getINSTANCETHREAD().start();
+            return true;
+        } else if (!aWorld.isRemote && !GT_Runnable_MachineBlockUpdate.isAllowedToRun()){
+            GT_Runnable_MachineBlockUpdate.setMachineUpdateValues(aWorld, aX, aY, aZ);
+            return true;
+        }
+        return false;
     }
 
     /**
diff --git a/src/main/java/gregtech/api/threads/GT_Runnable_MachineBlockUpdate.java b/src/main/java/gregtech/api/threads/GT_Runnable_MachineBlockUpdate.java
index 92944d3e32..0eed84ef2e 100644
--- a/src/main/java/gregtech/api/threads/GT_Runnable_MachineBlockUpdate.java
+++ b/src/main/java/gregtech/api/threads/GT_Runnable_MachineBlockUpdate.java
@@ -1,22 +1,119 @@
 package gregtech.api.threads;
 
 import gregtech.api.GregTech_API;
+
+import gregtech.api.interfaces.metatileentity.IMetaTileEntity;
+import gregtech.api.interfaces.tileentity.IGregTechTileEntity;
 import gregtech.api.interfaces.tileentity.IMachineBlockUpdateable;
+import gregtech.api.metatileentity.implementations.GT_MetaPipeEntity_Cable;
+import gregtech.api.metatileentity.implementations.GT_MetaPipeEntity_Fluid;
+import gregtech.api.metatileentity.implementations.GT_MetaPipeEntity_Item;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.world.ChunkPosition;
 import net.minecraft.world.World;
 
-import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Queue;
+import java.util.Set;
+import java.util.concurrent.ConcurrentLinkedQueue;
 
 public class GT_Runnable_MachineBlockUpdate implements Runnable {
-    private final int mX, mY, mZ;
-    private final World mWorld;
 
-    public GT_Runnable_MachineBlockUpdate(World aWorld, int aX, int aY, int aZ) {
-        mWorld = aWorld;
-        mX = aX;
-        mY = aY;
-        mZ = aZ;
+    private static int mX;
+    private static int mY;
+    private static int mZ;
+    private static World mWorld;
+    private static final Set<ChunkPosition> mVisited = new HashSet<>(80);
+
+    //Threading
+    private static boolean allowedToRun; //makes if this thread is idle
+    private static final Queue<Coordinates> toUpdate = new ConcurrentLinkedQueue<>(); //blocks added while this thread ran
+    private static final Thread INSTANCETHREAD = new Thread(new GT_Runnable_MachineBlockUpdate()); //Instance of this thread
+
+    //This class should never be initiated outside of this class!
+    private GT_Runnable_MachineBlockUpdate() {
+    }
+
+    public static synchronized void setmX(int mX) {
+        GT_Runnable_MachineBlockUpdate.mX = mX;
+    }
+
+    public static synchronized void setmY(int mY) {
+        GT_Runnable_MachineBlockUpdate.mY = mY;
+    }
+
+    public static synchronized void setmZ(int mZ) {
+        GT_Runnable_MachineBlockUpdate.mZ = mZ;
+    }
+
+    public static synchronized void setmWorld(World mWorld) {
+        GT_Runnable_MachineBlockUpdate.mWorld = mWorld;
+    }
+
+    /**
+     * Clears the mVisited HashSet
+     */
+    public static synchronized void resetVisited() {
+        synchronized (GT_Runnable_MachineBlockUpdate.mVisited) {
+            GT_Runnable_MachineBlockUpdate.mVisited.clear();
+        }
+    }
+
+    /**
+     *  Never call this Method without checking if the thead is NOT allowed to run!
+     */
+    private static void setMachineUpdateValuesUnsafe(World aWorld, int aX, int aY, int aZ){
+        GT_Runnable_MachineBlockUpdate.setmZ(aZ);
+        GT_Runnable_MachineBlockUpdate.setmY(aY);
+        GT_Runnable_MachineBlockUpdate.setmX(aX);
+        GT_Runnable_MachineBlockUpdate.setmWorld(aWorld);
+        GT_Runnable_MachineBlockUpdate.resetVisited();
+        GT_Runnable_MachineBlockUpdate.setAllowedToRun(true);
+    }
+
+    /**
+     * If the thread is idleing, sets new values and remove the idle flag, otherwise, queue the cooridinates.
+     */
+    public static synchronized void setMachineUpdateValues(World aWorld, int aX, int aY, int aZ) {
+        if (GT_Runnable_MachineBlockUpdate.isAllowedToRun()) {
+            toUpdate.add(new Coordinates(aX, aY, aZ, aWorld));
+        } else {
+            GT_Runnable_MachineBlockUpdate.setMachineUpdateValuesUnsafe(aWorld, aX, aY, aZ);
+        }
+    }
+
+    private static class Coordinates {
+
+        private final int mX;
+        private final int mY;
+        private final int mZ;
+        private final World mWorld;
+
+        public Coordinates(int mX, int mY, int mZ, World mWorld) {
+            this.mX = mX;
+            this.mY = mY;
+            this.mZ = mZ;
+            this.mWorld = mWorld;
+        }
+
+        /**
+         * Updated the Main Update Thread while its Idle
+         */
+        public void update() {
+            GT_Runnable_MachineBlockUpdate.setMachineUpdateValues(this.mWorld,this.mX,this.mY,this.mZ);
+        }
+    }
+
+    public static synchronized boolean isAllowedToRun() {
+        return allowedToRun;
+    }
+
+    public static synchronized void setAllowedToRun(boolean unlocked) {
+        GT_Runnable_MachineBlockUpdate.allowedToRun = unlocked;
+    }
+
+    public static Thread getINSTANCETHREAD() {
+        return INSTANCETHREAD;
     }
 
     private static void stepToUpdateMachine(World aWorld, int aX, int aY, int aZ, ArrayList<ChunkPosition> aList) {
@@ -32,12 +129,26 @@ public class GT_Runnable_MachineBlockUpdate implements Runnable {
             if (!aList.contains(new ChunkPosition(aX, aY, aZ + 1))) stepToUpdateMachine(aWorld, aX, aY, aZ + 1, aList);
             if (!aList.contains(new ChunkPosition(aX, aY, aZ - 1))) stepToUpdateMachine(aWorld, aX, aY, aZ - 1, aList);
         }
+
     }
 
     @Override
     public void run() {
-        try {
-            stepToUpdateMachine(mWorld, mX, mY, mZ, new ArrayList<ChunkPosition>());
-        } catch (Throwable e) {/**/}
+        for(;;) { //infinite loop
+            if (isAllowedToRun()) {//Are we ready to work?
+                try {
+                    stepToUpdateMachine(mX, mY, mZ);
+                } catch (Throwable e) {/**/}
+                setAllowedToRun(false); //Work is finished, wait for new Coords.
+            } else {
+                //Checkes if the Update Queue has members
+                //DO NOT USE OPTIONALS HERE!
+                synchronized (toUpdate) {
+                    Coordinates coordinates = toUpdate.poll();
+                    if (coordinates != null)
+                        coordinates.update();
+                }
+            }
+        }
     }
 }
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