3 files changed, 18 insertions, 3 deletions

diff --git a/Tools/AnvilStats/AnvilStats.txt b/Tools/AnvilStats/AnvilStats.txt
index 19aa4f324..1d8130aa2 100644
--- a/Tools/AnvilStats/AnvilStats.txt
+++ b/Tools/AnvilStats/AnvilStats.txt
@@ -15,6 +15,7 @@ Possible usage:
   - count the per-chunk density of specific blocks
   - count the per-chunk density of dungeons, by measuring the number of zombie/skeleton/regularspider spawners
   - count the per-chunk-per-biome density of trees, by measuring the number of dirt-log vertical transitions, correlating to biome data
+  - draw a vertical map of the world based on a specific measured value (biome, elevation, ...)
 
 This project is Windows-only, although it shouldn't be too difficult to make it portable.
 
diff --git a/Tools/AnvilStats/Callback.h b/Tools/AnvilStats/Callback.h
index 83b330651..eed51a41c 100644
--- a/Tools/AnvilStats/Callback.h
+++ b/Tools/AnvilStats/Callback.h
@@ -22,17 +22,20 @@ class cParsedNBT;
 
 /** The base class for all chunk-processor callbacks, declares the interface.
 The processor calls each virtual function in the order they are declared here with the specified args.
-If the function returns true, the processor moves on to next chunk and starts calling the callbacks again from start with
-the new chunk data.
+If the function returns true, the processor doesn't process the data item, moves on to the next chunk
+and starts calling the callbacks again from start with the new chunk data.
 So if a statistics collector doesn't need data decompression at all, it can stop the processor from doing so early-enough
 and still get meaningful data.
-A callback is guaranteed to run in a single thread and always the same thread.
+A callback is guaranteed to run in a single thread and always the same thread for the same chunk.
 A callback is guaranteed to run on all chunks in a region and one region is guaranteed to be handled by only callback.
 */
 class cCallback abstract
 {
 public:
 	virtual ~cCallback() {}  // Force a virtual destructor in each descendant
+
+	/// Called when a new region file is about to be opened; by default allow the region
+	virtual bool OnNewRegion(int a_RegionX, int a_RegionZ) { return false; }
 	
 	/// Called to inform the stats module of the chunk coords for newly processing chunk
 	virtual bool OnNewChunk(int a_ChunkX, int a_ChunkZ) = 0;
@@ -118,6 +121,9 @@ public:
 		int a_TicksLeft,
 		int a_PosX, int a_PosY, int a_PosZ
 	) { return true; }
+	
+	/// Called after the entire region file has been processed. No more callbacks for this region will be called. No processing by default
+	virtual void OnRegionFinished(int a_RegionX, int a_RegionZ) {}
 } ;
 
 typedef std::vector<cCallback *> cCallbacks;
diff --git a/Tools/AnvilStats/Processor.cpp b/Tools/AnvilStats/Processor.cpp
index e7f7eb21d..8e1cc4c4b 100644
--- a/Tools/AnvilStats/Processor.cpp
+++ b/Tools/AnvilStats/Processor.cpp
@@ -76,6 +76,12 @@ void cProcessor::cThread::ProcessFile(const AString & a_FileName)
 		return;
 	}
 
+	if (m_Callback.OnNewRegion(RegionX, RegionZ))
+	{
+		// Callback doesn't want the region file processed
+		return;
+	}
+	
 	cFile f;
 	if (!f.Open(a_FileName, cFile::fmRead))
 	{
@@ -92,6 +98,8 @@ void cProcessor::cThread::ProcessFile(const AString & a_FileName)
 	}
 	
 	ProcessFileData(FileContents.data(), FileContents.size(), RegionX * 32, RegionZ * 32);
+	
+	m_Callback.OnRegionFinished(RegionX, RegionZ);
 }