1 files changed, 104 insertions, 0 deletions

diff --git a/src/BlockTracer.h b/src/BlockTracer.h
new file mode 100644
index 000000000..d0a34811d
--- /dev/null
+++ b/src/BlockTracer.h
@@ -0,0 +1,104 @@
+
+// BlockTracer.h
+
+// Declares the classes common for all blocktracers
+
+
+
+
+
+#pragma once
+
+
+
+
+
+// fwd: World.h
+class cWorld;
+
+
+
+
+
+class cBlockTracer abstract
+{
+public:
+	/** The callback class is used to notify the caller of individual events that are being traced.
+	*/
+	class cCallbacks abstract
+	{
+	public:
+		/** Called on each block encountered along the path, including the first block (path start)
+		When this callback returns true, the tracing is aborted.
+		*/
+		virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta, char a_EntryFace) = 0;
+		
+		/** Called on each block encountered along the path, including the first block (path start), if chunk data is not loaded
+		When this callback returns true, the tracing is aborted.
+		*/
+		virtual bool OnNextBlockNoData(int a_BlockX, int a_BlockY, int a_BlockZ, char a_EntryFace) { return false; }
+		
+		/** Called when the path goes out of world, either below (a_BlockY < 0) or above (a_BlockY >= cChunkDef::Height)
+		The coords specify the exact point at which the path exited the world.
+		If this callback returns true, the tracing is aborted.
+		Note that some paths can go out of the world and come back again (parabola),
+		in such a case this callback is followed by OnIntoWorld() and further OnNextBlock() calls
+		*/
+		virtual bool OnOutOfWorld(double a_BlockX, double a_BlockY, double a_BlockZ) { return false; }
+		
+		/** Called when the path goes into the world, from either below (a_BlockY < 0) or above (a_BlockY >= cChunkDef::Height)
+		The coords specify the exact point at which the path entered the world.
+		If this callback returns true, the tracing is aborted.
+		Note that some paths can go out of the world and come back again (parabola),
+		in such a case this callback is followed by further OnNextBlock() calls
+		*/
+		virtual bool OnIntoWorld(double a_BlockX, double a_BlockY, double a_BlockZ) { return false; }
+		
+		/** Called when the path is sure not to hit any more blocks.
+		Note that for some shapes this might never happen (line with constant Y)
+		*/
+		virtual void OnNoMoreHits(void) {}
+		
+		/** Called when the block tracing walks into a chunk that is not allocated.
+		This usually means that the tracing is aborted.
+		*/
+		virtual void OnNoChunk(void) {}
+	} ;
+	
+	
+	/// Creates the BlockTracer parent with the specified callbacks
+	cBlockTracer(cWorld & a_World, cCallbacks & a_Callbacks) :
+		m_World(&a_World),
+		m_Callbacks(&a_Callbacks)
+	{
+	}
+	
+	
+	/// Sets new world, returns the old one. Note that both need to be valid
+	cWorld & SetWorld(cWorld & a_World)
+	{
+		cWorld & Old = *m_World;
+		m_World = &a_World;
+		return Old;
+	}
+	
+	
+	/// Sets new callbacks, returns the old ones. Note that both need to be valid
+	cCallbacks & SetCallbacks(cCallbacks & a_NewCallbacks)
+	{
+		cCallbacks & Old = *m_Callbacks;
+		m_Callbacks = &a_NewCallbacks;
+		return Old;
+	}
+	
+protected:
+	/// The world upon which to operate
+	cWorld * m_World;
+	
+	/// The callback to use for reporting
+	cCallbacks * m_Callbacks;
+} ;
+
+
+
+