1 files changed, 135 insertions, 7 deletions

diff --git a/src/Blocks/BlockSapling.h b/src/Blocks/BlockSapling.h
index bec79c6f3..c15e0a195 100644
--- a/src/Blocks/BlockSapling.h
+++ b/src/Blocks/BlockSapling.h
@@ -3,6 +3,7 @@
 
 #include "BlockHandler.h"
 #include "../World.h"
+#include "../FastRandom.h"
 
 
 
@@ -34,17 +35,144 @@ public:
 	virtual void OnUpdate(cChunkInterface & cChunkInterface, cWorldInterface & a_WorldInterface, cBlockPluginInterface & a_PluginInterface, cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ) override
 	{
 		NIBBLETYPE Meta = a_Chunk.GetMeta(a_RelX, a_RelY, a_RelZ);
-		
-		if ((Meta & 0x08) != 0)
+		NIBBLETYPE Light = std::max(a_Chunk.GetBlockLight(a_RelX, a_RelY, a_RelZ), a_Chunk.GetTimeAlteredLight(a_Chunk.GetSkyLight(a_RelX, a_RelY, a_RelZ)));
+
+		// Only grow if we have the right amount of light
+		if (Light > 8)
+		{
+			cFastRandom random;
+			// Only grow if we are in the right growth stage and have the right amount of space around them.
+			if (((Meta & 0x08) != 0) && (random.NextInt(99) < 45) && CanGrowAt(a_Chunk, a_RelX, a_RelY, a_RelZ, Meta))
+			{
+				int BlockX = a_RelX + a_Chunk.GetPosX() * cChunkDef::Width;
+				int BlockZ = a_RelZ + a_Chunk.GetPosZ() * cChunkDef::Width;
+				a_Chunk.GetWorld()->GrowTree(BlockX, a_RelY, BlockZ);
+			}
+			// Only move to the next growth stage if we haven't gone there yet
+			else if (((Meta & 0x08) == 0) && (random.NextInt(99) < 45))
+			{
+				a_Chunk.SetMeta(a_RelX, a_RelY, a_RelZ, Meta | 0x08);
+			}
+		}
+	}
+
+	bool CanGrowAt(cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ, NIBBLETYPE a_Meta)
+	{
+		a_Meta = a_Meta & 0x07;
+		int CheckHeight = 0;
+		bool LargeTree = false;
+
+		// Get the height to check against
+		switch (a_Meta)
 		{
-			int BlockX = a_RelX + a_Chunk.GetPosX() * cChunkDef::Width;
-			int BlockZ = a_RelZ + a_Chunk.GetPosZ() * cChunkDef::Width;
-			a_Chunk.GetWorld()->GrowTree(BlockX, a_RelY, BlockZ);
+			case E_META_SAPLING_APPLE:
+			{
+				CheckHeight = 5;
+				break;
+			}
+			case E_META_SAPLING_CONIFER:
+			{
+				CheckHeight = 7;
+				if (IsLargeTree(a_Chunk, a_RelX, a_RelY, a_RelZ, a_Meta))
+				{
+					CheckHeight = 16;
+					LargeTree = true;
+				}
+				break;
+			}
+			case E_META_SAPLING_BIRCH:
+			{
+				CheckHeight = 6;
+				break;
+			}
+			case E_META_SAPLING_JUNGLE:
+			{
+				CheckHeight = 7;
+				if (IsLargeTree(a_Chunk, a_RelX, a_RelY, a_RelZ, a_Meta))
+				{
+					CheckHeight = 13;
+					LargeTree = true;
+				}
+				break;
+			}
+			// Dark Oaks only grow in a 2x2 area
+			case E_META_SAPLING_DARK_OAK:
+			{
+				if (!IsLargeTree(a_Chunk, a_RelX, a_RelY, a_RelZ, a_Meta))
+				{
+					return false;
+				}
+				CheckHeight = 7;
+				LargeTree = true;
+				break;
+			}
 		}
-		else
+		// We should always get a valid CheckHeight
+		ASSERT(CheckHeight != 0);
+
+		// Don't grow a tree if we don't have enough space left above it in the chunk
+		if ((a_RelY + CheckHeight) > cChunkDef::Height)
+		{
+			return false;
+		}
+		bool CanGrow = true;
+
+		// Validate the neighbor blocks. They cannot be solid.
+		BLOCKTYPE check = E_BLOCK_AIR;
+		a_Chunk.UnboundedRelGetBlockType(a_RelX - 1, a_RelY, a_RelZ, check);
+		CanGrow = CanGrow && cBlockInfo::IsTransparent(check);
+
+		a_Chunk.UnboundedRelGetBlockType(a_RelX + 1, a_RelY, a_RelZ, check);
+		CanGrow = CanGrow && cBlockInfo::IsTransparent(check);
+
+		a_Chunk.UnboundedRelGetBlockType(a_RelX, a_RelY, a_RelZ - 1, check);
+		CanGrow = CanGrow && cBlockInfo::IsTransparent(check);
+
+		a_Chunk.UnboundedRelGetBlockType(a_RelX, a_RelY, a_RelZ + 1, check);
+		CanGrow = CanGrow && cBlockInfo::IsTransparent(check);
+
+
+
+		while (CheckHeight && CanGrow)
 		{
-			a_Chunk.SetMeta(a_RelX, a_RelY, a_RelZ, Meta | 0x08);
+			check = a_Chunk.GetBlock(a_RelX, a_RelY + CheckHeight, a_RelZ);
+			CanGrow = CanGrow && ((check == E_BLOCK_AIR) || (check == E_BLOCK_LEAVES));
+
+			// We have to check above the neighboring saplings as well
+			if (LargeTree)
+			{
+				a_Chunk.UnboundedRelGetBlockType(a_RelX + 1, a_RelY + CheckHeight, a_RelZ, check);
+				CanGrow = CanGrow && ((check == E_BLOCK_AIR) || (check == E_BLOCK_LEAVES));
+
+				a_Chunk.UnboundedRelGetBlockType(a_RelX, a_RelY + CheckHeight, a_RelZ + 1, check);
+				CanGrow = CanGrow && ((check == E_BLOCK_AIR) || (check == E_BLOCK_LEAVES));
+
+				a_Chunk.UnboundedRelGetBlockType(a_RelX + 1, a_RelY + CheckHeight, a_RelZ + 1, check);
+				CanGrow = CanGrow && ((check == E_BLOCK_AIR) || (check == E_BLOCK_LEAVES));
+			}
+
+			--CheckHeight;
 		}
+
+		return CanGrow;
+	}
+
+private:
+	bool IsLargeTree(cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ, NIBBLETYPE a_Meta)
+	{
+		BLOCKTYPE type;
+		NIBBLETYPE meta;
+		bool LargeTree = true;
+		a_Chunk.UnboundedRelGetBlock(a_RelX + 1, a_RelY, a_RelZ, type, meta);
+		LargeTree = LargeTree && (type == E_BLOCK_SAPLING) && ((a_Meta & meta) == a_Meta);
+
+		a_Chunk.UnboundedRelGetBlock(a_RelX + 1, a_RelY, a_RelZ + 1, type, meta);
+		LargeTree = LargeTree && (type == E_BLOCK_SAPLING) && ((a_Meta & meta) == a_Meta);
+
+		a_Chunk.UnboundedRelGetBlock(a_RelX, a_RelY, a_RelZ + 1, type, meta);
+		LargeTree = LargeTree && (type == E_BLOCK_SAPLING) && ((a_Meta & meta) == a_Meta);
+
+		return LargeTree;
 	}
 } ;