1 files changed, 271 insertions, 0 deletions

diff --git a/src/Blocks/BlockVines.h b/src/Blocks/BlockVines.h
new file mode 100644
index 000000000..d6eccd552
--- /dev/null
+++ b/src/Blocks/BlockVines.h
@@ -0,0 +1,271 @@
+#pragma once
+
+#include "BlockHandler.h"
+
+
+
+
+
+class cBlockVinesHandler final :
+	public cBlockHandler
+{
+	using Super = cBlockHandler;
+
+public:
+
+	using Super::Super;
+
+private:
+
+	static const NIBBLETYPE VINE_LOST_SUPPORT = 16;
+	static const NIBBLETYPE VINE_UNCHANGED = 17;
+
+
+	virtual bool CanBeAt(const cChunk & a_Chunk, const Vector3i a_Position, const NIBBLETYPE a_Meta) const override
+	{
+		return GetMaxMeta(a_Chunk, a_Position, a_Meta) != VINE_LOST_SUPPORT;
+	}
+
+
+	virtual cItems ConvertToPickups(const NIBBLETYPE a_BlockMeta, const cItem * const a_Tool) const override
+	{
+		// Only drops self when using shears, otherwise drops nothing:
+		if ((a_Tool == nullptr) || (a_Tool->m_ItemType != E_ITEM_SHEARS))
+		{
+			return {};
+		}
+		return cItem(E_BLOCK_VINES, 1, 0);
+	}
+
+
+
+
+
+	static char MetaDataToDirection(NIBBLETYPE a_MetaData)
+	{
+		switch (a_MetaData)
+		{
+			case 0x1: return BLOCK_FACE_NORTH;
+			case 0x4: return BLOCK_FACE_SOUTH;
+			case 0x8: return BLOCK_FACE_WEST;
+			case 0x2: return BLOCK_FACE_EAST;
+			default:  return BLOCK_FACE_TOP;
+		}
+	}
+
+
+
+
+
+	/** Returns true if the specified block type is good for vines to attach to */
+	static bool IsBlockAttachable(BLOCKTYPE a_BlockType)
+	{
+		switch (a_BlockType)
+		{
+			case E_BLOCK_CHEST:
+			case E_BLOCK_ENDER_CHEST:
+			case E_BLOCK_GLASS:
+			case E_BLOCK_PISTON:
+			case E_BLOCK_PISTON_EXTENSION:
+			case E_BLOCK_REDSTONE_REPEATER_OFF:
+			case E_BLOCK_REDSTONE_REPEATER_ON:
+			case E_BLOCK_STAINED_GLASS:
+			case E_BLOCK_STICKY_PISTON:
+			case E_BLOCK_TRAPPED_CHEST:
+			{
+				// You can't attach a vine to this solid blocks.
+				return false;
+			}
+			default:
+			{
+				return cBlockInfo::IsSolid(a_BlockType);
+			}
+		}
+	}
+
+
+
+
+
+	/** Returns the meta that has the maximum allowable sides of the vine, given the surroundings and current vine meta.
+	Returns special values for a vine that can continue to exist unchanged, or must die completely. */
+	static NIBBLETYPE GetMaxMeta(const cChunk & a_Chunk, const Vector3i a_Position, const NIBBLETYPE a_CurrentMeta)
+	{
+		static const struct
+		{
+			int x, z;
+			NIBBLETYPE Bit;
+		} Coords[] =
+		{
+			{ 0,  1, 1},  // south, ZP
+			{-1,  0, 2},  // west,  XM
+			{ 0, -1, 4},  // north, ZM
+			{ 1,  0, 8},  // east,  XP
+		} ;
+
+		NIBBLETYPE MaxMeta = 0;
+		for (auto & Coord : Coords)
+		{
+			BLOCKTYPE  BlockType;
+			NIBBLETYPE BlockMeta;
+			auto checkPos = a_Position.addedXZ(Coord.x, Coord.z);
+			if (
+				a_Chunk.UnboundedRelGetBlock(checkPos.x, checkPos.y, checkPos.z, BlockType, BlockMeta) &&
+				IsBlockAttachable(BlockType)
+			)
+			{
+				MaxMeta |= Coord.Bit;
+			}
+		}
+
+		// Check if vine above us, add its meta to MaxMeta:
+		if ((a_Position.y < cChunkDef::Height - 1) && (a_Chunk.GetBlock(a_Position.addedY(1)) == E_BLOCK_VINES))
+		{
+			MaxMeta |= a_Chunk.GetMeta(a_Position.addedY(1));
+		}
+
+		NIBBLETYPE Common = a_CurrentMeta & MaxMeta;  // Neighbors that we have and are legal.
+		if (Common != a_CurrentMeta)
+		{
+			bool HasTop = (a_Position.y < (cChunkDef::Height - 1)) && IsBlockAttachable(a_Chunk.GetBlock(a_Position.addedY(1)));
+			if ((Common == 0) && !HasTop)  // Meta equals 0 also means top. Make a last-ditch attempt to save the vine.
+			{
+				return VINE_LOST_SUPPORT;
+			}
+
+			return Common;
+		}
+
+		return VINE_UNCHANGED;
+	}
+
+
+
+
+
+	virtual void OnNeighborChanged(cChunkInterface & a_ChunkInterface, Vector3i a_BlockPos, eBlockFace a_WhichNeighbor) const override
+	{
+		a_ChunkInterface.DoWithChunkAt(a_BlockPos, [&](cChunk & a_Chunk)
+		{
+
+		const auto Position = cChunkDef::AbsoluteToRelative(a_BlockPos);
+		const auto MaxMeta = GetMaxMeta(a_Chunk, Position, a_Chunk.GetMeta(Position));
+
+		if (MaxMeta == VINE_UNCHANGED)
+		{
+			return false;
+		}
+
+		// There is a neighbor missing, need to update the meta or even destroy the block.
+
+		if (MaxMeta == VINE_LOST_SUPPORT)
+		{
+			// The vine just lost all its support, destroy the block:
+			a_Chunk.SetBlock(Position, E_BLOCK_AIR, 0);
+		}
+		else
+		{
+			// It lost some of its support, set it to what remains (SetBlock to notify neighbors):
+			a_Chunk.SetBlock(Position, E_BLOCK_VINES, MaxMeta);
+		}
+
+		return false;
+		});
+	}
+
+
+
+
+
+	virtual bool DoesIgnoreBuildCollision(const cWorld & a_World, const cItem & a_HeldItem, const Vector3i a_Position, const NIBBLETYPE a_Meta, const eBlockFace a_ClickedBlockFace, const bool a_ClickedDirectly) const override
+	{
+		return !a_ClickedDirectly || (a_HeldItem.m_ItemType != m_BlockType);
+	}
+
+
+
+
+
+	virtual void OnUpdate(
+		cChunkInterface & a_ChunkInterface,
+		cWorldInterface & a_WorldInterface,
+		cBlockPluginInterface & a_PluginInterface,
+		cChunk & a_Chunk,
+		const Vector3i a_RelPos
+	) const override
+	{
+		UNUSED(a_ChunkInterface);
+		UNUSED(a_WorldInterface);
+
+		// Vine cannot grow down if at the bottom:
+		auto GrowPos = a_RelPos.addedY(-1);
+		if (!cChunkDef::IsValidHeight(GrowPos.y))
+		{
+			return;
+		}
+
+		// Grow one block down, if possible:
+		BLOCKTYPE Block;
+		a_Chunk.UnboundedRelGetBlockType(GrowPos, Block);
+		if (Block == E_BLOCK_AIR)
+		{
+			auto WorldPos = a_Chunk.RelativeToAbsolute(GrowPos);
+			if (!a_PluginInterface.CallHookBlockSpread(WorldPos.x, WorldPos.y, WorldPos.z, ssVineSpread))
+			{
+				a_Chunk.UnboundedRelSetBlock(GrowPos, E_BLOCK_VINES, a_Chunk.GetMeta(a_RelPos));
+			}
+		}
+	}
+
+
+
+
+
+	virtual NIBBLETYPE MetaRotateCCW(NIBBLETYPE a_Meta) const override
+	{
+		return ((a_Meta >> 1) | (a_Meta << 3)) & 0x0f;  // Rotate bits to the right
+	}
+
+
+
+
+
+	virtual NIBBLETYPE MetaRotateCW(NIBBLETYPE a_Meta) const override
+	{
+		return ((a_Meta << 1) | (a_Meta >> 3)) & 0x0f;  // Rotate bits to the left
+	}
+
+
+
+
+
+	virtual NIBBLETYPE MetaMirrorXY(NIBBLETYPE a_Meta) const override
+	{
+		// Bits 2 and 4 stay, bits 1 and 3 swap
+		return static_cast<NIBBLETYPE>((a_Meta & 0x0a) | ((a_Meta & 0x01) << 2) | ((a_Meta & 0x04) >> 2));
+	}
+
+
+
+
+
+	virtual NIBBLETYPE MetaMirrorYZ(NIBBLETYPE a_Meta) const override
+	{
+		// Bits 1 and 3 stay, bits 2 and 4 swap
+		return static_cast<NIBBLETYPE>((a_Meta & 0x05) | ((a_Meta & 0x02) << 2) | ((a_Meta & 0x08) >> 2));
+	}
+
+
+
+
+
+	virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) const override
+	{
+		UNUSED(a_Meta);
+		return 7;
+	}
+} ;
+
+
+
+