Updated Bookshelves drop behaviour (#4567)

* Updated BookShelves Drop Behaviour

As described here : https://minecraft.gamepedia.com/Bookshelf#Loot

* Update src/Blocks/BlockBookShelf.h

* Update CONTRIBUTORS

CONTRIBUTORS

@@ -66,3 +66,4 @@ williamhatcher (Helped with API documentation updates and bug fixes)
 worktycho
 xoft (Mattes Dolak/madmaxoft on GH)
 Yeeeeezus (Donated AlchemistVillage prefabs)
+Xenoxis

src/Blocks/BlockBookShelf.h

@@ -0,0 +1,26 @@
+
+#pragma once
+
+#include "BlockHandler.h"
+
+
+
+
+class cBlockBookShelfHandler :
+	public cBlockHandler
+{
+	public:
+		cBlockBookShelfHandler(BLOCKTYPE a_BlockType) :
+			cBlockHandler(a_BlockType)
+		{
+		}
+
+		virtual cItems ConvertToPickups(NIBBLETYPE a_BlockMeta, cBlockEntity * a_BlockEntity, const cEntity * a_Digger, const cItem * a_Tool) override
+		{
+			if ((ItemCategory::IsTool(a_Tool->m_ItemType)) && (ToolHasSilkTouch(a_Tool)))
+			{
+				return cItem(m_BlockType, 1);
+			}
+			return cItem(E_ITEM_BOOK, 3);
+		}
+};

src/Blocks/BlockHandler.cpp

@@ -8,6 +8,7 @@
 #include "BlockAnvil.h"
 #include "BlockBed.h"
 #include "BlockBigFlower.h"
+#include "BlockBookShelf.h"
 #include "BlockBrewingStand.h"
 #include "BlockButton.h"
 #include "BlockCactus.h"
@@ -202,6 +203,7 @@ static cBlockHandler * CreateBlockHandler(BLOCKTYPE a_BlockType)
 		case E_BLOCK_BIRCH_FENCE:                   return new cBlockFenceHandler           (a_BlockType);
 		case E_BLOCK_BIRCH_FENCE_GATE:              return new cBlockFenceGateHandler       (a_BlockType);
 		case E_BLOCK_BIRCH_WOOD_STAIRS:             return new cBlockStairsHandler          (a_BlockType);
+		case E_BLOCK_BOOKCASE:                      return new cBlockBookShelfHandler       (a_BlockType);
 		case E_BLOCK_BREWING_STAND:                 return new cBlockBrewingStandHandler    (a_BlockType);
 		case E_BLOCK_BRICK_STAIRS:                  return new cBlockStairsHandler          (a_BlockType);
 		case E_BLOCK_BROWN_MUSHROOM:                return new cBlockMushroomHandler        (a_BlockType);

src/Blocks/CMakeLists.txt

@@ -14,6 +14,7 @@ SET (HDRS
 	BlockAnvil.h
 	BlockBed.h
 	BlockBigFlower.h
+	BlockBookShelf.h
 	BlockBrewingStand.h
 	BlockButton.h
 	BlockCactus.h