1 files changed, 16 insertions, 4 deletions
diff --git a/src/Blocks/BlockDirt.h b/src/Blocks/BlockDirt.h
index aae6719e2..cc0d845e4 100644
--- a/src/Blocks/BlockDirt.h
+++ b/src/Blocks/BlockDirt.h
@@ -52,14 +52,26 @@ public:
 				return;
 			}
 		}
-		
+
+		// Make sure that there is enough light at the source block to spread
+		if (!a_Chunk.GetWorld()->IsChunkLighted(a_Chunk.GetPosX(), a_Chunk.GetPosZ()))
+		{
+			a_Chunk.GetWorld()->QueueLightChunk(a_Chunk.GetPosX(), a_Chunk.GetPosZ());
+			return;
+		}
+		else if (std::max(a_Chunk.GetBlockLight(a_RelX, a_RelY + 1, a_RelZ), a_Chunk.GetTimeAlteredLight(a_Chunk.GetSkyLight(a_RelX, a_RelY + 1, a_RelZ))) < 9)
+		{
+			// Source block is not bright enough to spread
+			return;
+		}
+
 		// Grass spreads to adjacent dirt blocks:
 		cFastRandom rand;
 		for (int i = 0; i < 2; i++)  // Pick two blocks to grow to
 		{
-			int OfsX = rand.NextInt(3, a_RelX) - 1;  // [-1 .. 1]
-			int OfsY = rand.NextInt(5, a_RelY) - 3;  // [-3 .. 1]
-			int OfsZ = rand.NextInt(3, a_RelZ) - 1;  // [-1 .. 1]
+			int OfsX = rand.NextInt(3) - 1;  // [-1 .. 1]
+			int OfsY = rand.NextInt(5) - 3;  // [-3 .. 1]
+			int OfsZ = rand.NextInt(3) - 1;  // [-1 .. 1]
 	
 			BLOCKTYPE  DestBlock;
 			NIBBLETYPE DestMeta;