Working on drive design.

Several particle crash fixes.

src/main/java/appeng/block/storage/DriveSlotCellType.java

@@ -0,0 +1,50 @@
+/*
+ * This file is part of Applied Energistics 2.
+ * Copyright (c) 2013 - 2014, AlgorithmX2, All rights reserved.
+ *
+ * Applied Energistics 2 is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Applied Energistics 2 is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Applied Energistics 2.  If not, see <http://www.gnu.org/licenses/lgpl>.
+ */
+
+package appeng.block.storage;
+
+
+import net.minecraft.util.IStringSerializable;
+
+
+/**
+ * Describes the type of cell present in a slot.
+ */
+public enum DriveSlotCellType implements IStringSerializable
+{
+
+	EMPTY("empty"),
+
+	ITEM("item"),
+
+	FLUID("fluid");
+
+	private final String name;
+
+	DriveSlotCellType(String name )
+	{
+		this.name = name;
+	}
+
+	@Override
+	public String getName()
+	{
+		return this.name;
+	}
+
+}

src/main/java/appeng/block/storage/DriveSlotsState.java

@@ -20,6 +20,9 @@ package appeng.block.storage;
 
 
 import appeng.api.implementations.tiles.IChestOrDrive;
+import com.google.common.base.Preconditions;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
 
 
 /**
@@ -28,25 +31,37 @@ import appeng.api.implementations.tiles.IChestOrDrive;
 public class DriveSlotsState
 {
 
-	private final DriveSlotState[] slots;
+	private final Item[] cells;
 
-	private DriveSlotsState( DriveSlotState[] slots )
-	{
-		this.slots = slots;
+	private final DriveSlotState[] states;
+
+	public DriveSlotsState(Item[] cells, DriveSlotState[] states) {
+		Preconditions.checkArgument(cells.length == states.length);
+		this.cells = cells;
+		this.states = states;
 	}
 
-	public DriveSlotState getState( int index )
+	public DriveSlotState getState(int index )
 	{
-		if( index >= this.slots.length )
+		if( index >= this.states.length )
 		{
 			return DriveSlotState.EMPTY;
 		}
-		return this.slots[index];
+		return this.states[index];
+	}
+
+	public Item getCell(int index )
+	{
+		if( index >= this.cells.length )
+		{
+			return null;
+		}
+		return this.cells[index];
 	}
 
 	public int getSlotCount()
 	{
-		return this.slots.length;
+		return this.cells.length;
 	}
 
 	/**
@@ -54,35 +69,39 @@ public class DriveSlotsState
 	 */
 	public static DriveSlotsState fromChestOrDrive( IChestOrDrive chestOrDrive )
 	{
-		DriveSlotState[] slots = new DriveSlotState[chestOrDrive.getCellCount()];
+		DriveSlotState[] states = new DriveSlotState[chestOrDrive.getCellCount()];
+		Item[] cells = new Item[chestOrDrive.getCellCount()];
 		for( int i = 0; i < chestOrDrive.getCellCount(); i++ )
 		{
+			cells[i] = chestOrDrive.getCellItem(i);
+
 			if( !chestOrDrive.isPowered() )
 			{
 				if( chestOrDrive.getCellStatus( i ) != 0 )
 				{
-					slots[i] = DriveSlotState.OFFLINE;
+					states[i] = DriveSlotState.OFFLINE;
 				}
 				else
 				{
-					slots[i] = DriveSlotState.EMPTY;
+					states[i] = DriveSlotState.EMPTY;
 				}
 			}
 			else
 			{
-				slots[i] = DriveSlotState.fromCellStatus( chestOrDrive.getCellStatus( i ) );
+				states[i] = DriveSlotState.fromCellStatus( chestOrDrive.getCellStatus( i ) );
 			}
 		}
-		return new DriveSlotsState( slots );
+		return new DriveSlotsState( cells, states );
 	}
 
 	public static DriveSlotsState createEmpty( int slotCount )
 	{
-		DriveSlotState[] slots = new DriveSlotState[slotCount];
+		DriveSlotState[] states = new DriveSlotState[slotCount];
+		Item[] cells = new Item[slotCount];
 		for( int i = 0; i < slotCount; i++ )
 		{
-			slots[i] = DriveSlotState.EMPTY;
+			states[i] = DriveSlotState.EMPTY;
 		}
-		return new DriveSlotsState( slots );
+		return new DriveSlotsState( cells, states );
 	}
 }