Add in the basic IBlockLiquid interface. The actual block implementation

will follow.

common/net/minecraftforge/liquids/IBlockLiquid.java

@@ -0,0 +1,59 @@
+package net.minecraftforge.liquids;
+
+import net.minecraft.src.NBTTagCompound;
+
+/**
+ * Implementors of this interface are a liquid which may receive a block implementation and can be placed in the world.
+ *
+ * @author cpw
+ *
+ */
+public interface IBlockLiquid extends ILiquid {
+	/**
+	 * Controls the type of block that is generated by this IBlockLiquid
+	 * @author cpw
+	 *
+	 */
+	public enum BlockType {
+		/**
+		 * No block. Completeness really.
+		 */
+		NONE,
+		/**
+		 * Vanilla style block, up to 8 flowing states. May be able to generate new sources.
+		 */
+		VANILLA,
+		/**
+		 * Finite liquid style, uses cellular automata to model flowing behaviour.
+		 */
+		FINITE;
+	}
+
+	/**
+	 * Can this liquid, when placed in a specific configuration, generate new source blocks of the liquid.
+	 * @return
+	 */
+	public boolean willGenerateSources();
+
+	/**
+	 * @return the distance this liquid will flow if placed in the world. Maximum of 7 levels for vanilla types.
+	 */
+	public int getFlowDistance();
+
+	/**
+	 * @return the RGB rendering for this liquid
+	 */
+	public byte[] getLiquidRGB();
+
+	/**
+	 * Get the texture file for rendering the liquid
+	 * @return
+	 */
+	public String getLiquidBlockTextureFile();
+	/**
+	 * Custom properties of the liquid.
+	 * @return
+	 */
+	public NBTTagCompound getLiquidProperties();
+
+}

common/net/minecraftforge/liquids/ILiquid.java

@@ -1,20 +1,35 @@
-/** 
+/**
  * Copyright (c) SpaceToad, 2011
  * http://www.mod-buildcraft.com
- * 
- * BuildCraft is distributed under the terms of the Minecraft Mod Public 
+ *
+ * BuildCraft is distributed under the terms of the Minecraft Mod Public
  * License 1.0, or MMPL. Please check the contents of the license located in
  * http://www.mod-buildcraft.com/MMPL-1.0.txt
  */
 
 package net.minecraftforge.liquids;
 
+/**
+ * Liquids implement this interface
+ *
+ */
 public interface ILiquid {
 
+	/**
+	 * The itemId of the liquid item
+	 * @return
+	 */
 	public int stillLiquidId();
 
+	/**
+	 * Is this liquid a metadata based liquid
+	 * @return
+	 */
 	public boolean isMetaSensitive();
 
+	/**
+	 * The item metadata of the liquid
+	 * @return
+	 */
 	public int stillLiquidMeta();
-
 }