Added Fluid Tank comparator support, fixed Gas Tank comparator support

src/main/java/mekanism/common/block/BlockMachine.java

@@ -802,6 +802,25 @@ public class BlockMachine extends BlockContainer implements ISpecialBounds, IBlo
 		return world.setBlockToAir(x, y, z);
 	}
 	
+	@Override
+	public boolean hasComparatorInputOverride()
+	{
+		return true;
+	}
+	
+	@Override
+	public int getComparatorInputOverride(World world, int x, int y, int z, int par5)
+	{
+		TileEntity tileEntity = world.getTileEntity(x, y, z);
+		
+		if(tileEntity instanceof TileEntityFluidTank)
+		{
+			return ((TileEntityFluidTank)tileEntity).getRedstoneLevel();
+		}
+		
+		return 0;
+	}
+	
 	private boolean manageInventory(EntityPlayer player, TileEntityFluidTank tileEntity)
 	{
 		ItemStack itemStack = player.getCurrentEquippedItem();

src/main/java/mekanism/common/tile/TileEntityFluidTank.java

@@ -27,6 +27,7 @@ import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.tileentity.TileEntity;
+import net.minecraft.util.MathHelper;
 import net.minecraftforge.common.util.ForgeDirection;
 import net.minecraftforge.fluids.Fluid;
 import net.minecraftforge.fluids.FluidContainerRegistry;
@@ -60,6 +61,8 @@ public class TileEntityFluidTank extends TileEntityContainerBlock implements IAc
 	
 	public boolean needsPacket;
 	
+	public int currentRedstoneLevel;
+	
 	public TileComponentSecurity securityComponent = new TileComponentSecurity(this);
 	
 	public TileEntityFluidTank() 
@@ -139,6 +142,14 @@ public class TileEntityFluidTank extends TileEntityContainerBlock implements IAc
 				activeEmit();
 			}
 			
+			int newRedstoneLevel = getRedstoneLevel();
+
+			if(newRedstoneLevel != currentRedstoneLevel)
+			{
+				markDirty();
+				currentRedstoneLevel = newRedstoneLevel;
+			}
+			
 			if(needsPacket)
 			{
 				Mekanism.packetHandler.sendToAllAround(new TileEntityMessage(Coord4D.get(this), getNetworkedData(new ArrayList())), Coord4D.get(this).getTargetPoint(50));
@@ -353,6 +364,12 @@ public class TileEntityFluidTank extends TileEntityContainerBlock implements IAc
 		}
 	}
 	
+	public int getRedstoneLevel()
+	{
+        double fractionFull = (float)fluidTank.getFluidAmount()/(float)fluidTank.getCapacity();
+        return MathHelper.floor_float((float)(fractionFull * 14.0F)) + (fractionFull > 0 ? 1 : 0);
+	}
+	
 	public int getCurrentNeeded()
 	{
 		int needed = fluidTank.getCapacity()-fluidTank.getFluidAmount();

src/main/java/mekanism/common/tile/TileEntityGasTank.java

@@ -53,6 +53,8 @@ public class TileEntityGasTank extends TileEntityContainerBlock implements IGasH
 
 	public int currentGasAmount;
 	
+	public int currentRedstoneLevel;
+
 	/** This machine's current RedstoneControl type. */
 	public RedstoneControl controlType;
 	
@@ -127,6 +129,14 @@ public class TileEntityGasTank extends TileEntityContainerBlock implements IGasH
 			}
 			
 			currentGasAmount = newGasAmount;
+			
+			int newRedstoneLevel = getRedstoneLevel();
+
+			if(newRedstoneLevel != currentRedstoneLevel)
+			{
+				markDirty();
+				currentRedstoneLevel = newRedstoneLevel;
+			}
 		}
 	}