17 files changed, 568 insertions, 439 deletions

diff --git a/Tools/QtBiomeVisualiser/BiomeView.cpp b/Tools/QtBiomeVisualiser/BiomeView.cpp
index b44b935d7..c77b39482 100644
--- a/Tools/QtBiomeVisualiser/BiomeView.cpp
+++ b/Tools/QtBiomeVisualiser/BiomeView.cpp
@@ -1,8 +1,8 @@
 #include "Globals.h"
 #include "BiomeView.h"
-#include "QtChunk.h"
 #include <QPainter>
 #include <QResizeEvent>
+#include "Region.h"
 
 
 
@@ -14,6 +14,116 @@ static const int DELTA_STEP = 120;  // The normal per-notch wheel delta
 
 
 
+/** Map for converting biome values to colors. Initialized from biomeColors[]. */
+static uchar biomeToColor[256 * 4];
+
+/** Map for converting biome values to colors. Used to initialize biomeToColor[].*/
+static struct
+{
+	EMCSBiome m_Biome;
+	uchar m_Color[3];
+} biomeColors[] =
+{
+	{ biOcean,                { 0x00, 0x00, 0x70 }, },
+	{ biPlains,               { 0x8d, 0xb3, 0x60 }, },
+	{ biDesert,               { 0xfa, 0x94, 0x18 }, },
+	{ biExtremeHills,         { 0x60, 0x60, 0x60 }, },
+	{ biForest,               { 0x05, 0x66, 0x21 }, },
+	{ biTaiga,                { 0x0b, 0x66, 0x59 }, },
+	{ biSwampland,            { 0x2f, 0xff, 0xda }, },
+	{ biRiver,                { 0x30, 0x30, 0xaf }, },
+	{ biHell,                 { 0x7f, 0x00, 0x00 }, },
+	{ biSky,                  { 0x00, 0x7f, 0xff }, },
+	{ biFrozenOcean,          { 0xa0, 0xa0, 0xdf }, },
+	{ biFrozenRiver,          { 0xa0, 0xa0, 0xff }, },
+	{ biIcePlains,            { 0xff, 0xff, 0xff }, },
+	{ biIceMountains,         { 0xa0, 0xa0, 0xa0 }, },
+	{ biMushroomIsland,       { 0xff, 0x00, 0xff }, },
+	{ biMushroomShore,        { 0xa0, 0x00, 0xff }, },
+	{ biBeach,                { 0xfa, 0xde, 0x55 }, },
+	{ biDesertHills,          { 0xd2, 0x5f, 0x12 }, },
+	{ biForestHills,          { 0x22, 0x55, 0x1c }, },
+	{ biTaigaHills,           { 0x16, 0x39, 0x33 }, },
+	{ biExtremeHillsEdge,     { 0x7f, 0x8f, 0x7f }, },
+	{ biJungle,               { 0x53, 0x7b, 0x09 }, },
+	{ biJungleHills,          { 0x2c, 0x42, 0x05 }, },
+
+	{ biJungleEdge,           { 0x62, 0x8b, 0x17 }, },
+	{ biDeepOcean,            { 0x00, 0x00, 0x30 },	},
+	{ biStoneBeach,           { 0xa2, 0xa2, 0x84 },	},
+	{ biColdBeach,            { 0xfa, 0xf0, 0xc0 },	},
+	{ biBirchForest,          { 0x30, 0x74, 0x44 },	},
+	{ biBirchForestHills,     { 0x1f, 0x5f, 0x32 },	},
+	{ biRoofedForest,         { 0x40, 0x51, 0x1a },	},
+	{ biColdTaiga,            { 0x31, 0x55, 0x4a },	},
+	{ biColdTaigaHills,       { 0x59, 0x7d, 0x72 },	},
+	{ biMegaTaiga,            { 0x59, 0x66, 0x51 },	},
+	{ biMegaTaigaHills,       { 0x59, 0x66, 0x59 },	},
+	{ biExtremeHillsPlus,     { 0x50, 0x70, 0x50 },	},
+	{ biSavanna,              { 0xbd, 0xb2, 0x5f },	},
+	{ biSavannaPlateau,       { 0xa7, 0x9d, 0x64 },	},
+	{ biMesa,                 { 0xd9, 0x45, 0x15 },	},
+	{ biMesaPlateauF,         { 0xb0, 0x97, 0x65 },	},
+	{ biMesaPlateau,          { 0xca, 0x8c, 0x65 },	},
+
+	// M variants:
+	{ biSunflowerPlains,      { 0xb5, 0xdb, 0x88 }, },
+	{ biDesertM,              { 0xff, 0xbc, 0x40 }, },
+	{ biExtremeHillsM,        { 0x88, 0x88, 0x88 }, },
+	{ biFlowerForest,         { 0x2d, 0x8e, 0x49 }, },
+	{ biTaigaM,               { 0x33, 0x8e, 0x81 }, },
+	{ biSwamplandM,           { 0x07, 0xf9, 0xb2 }, },
+	{ biIcePlainsSpikes,      { 0xb4, 0xdc, 0xdc }, },
+	{ biJungleM,              { 0x7b, 0xa3, 0x31 }, },
+	{ biJungleEdgeM,          { 0x62, 0x8b, 0x17 }, },
+	{ biBirchForestM,         { 0x58, 0x9c, 0x6c }, },
+	{ biBirchForestHillsM,    { 0x47, 0x87, 0x5a }, },
+	{ biRoofedForestM,        { 0x68, 0x79, 0x42 }, },
+	{ biColdTaigaM,           { 0x24, 0x3f, 0x36 }, },
+	{ biMegaSpruceTaiga,      { 0x45, 0x4f, 0x3e }, },
+	{ biMegaSpruceTaigaHills, { 0x45, 0x4f, 0x4e }, },
+	{ biExtremeHillsPlusM,    { 0x78, 0x98, 0x78 }, },
+	{ biSavannaM,             { 0xe5, 0xda, 0x87 }, },
+	{ biSavannaPlateauM,      { 0xa7, 0x9d, 0x74 }, },
+	{ biMesaBryce,            { 0xff, 0x6d, 0x3d }, },
+	{ biMesaPlateauFM,        { 0xd8, 0xbf, 0x8d }, },
+	{ biMesaPlateauM,         { 0xf2, 0xb4, 0x8d }, },
+} ;
+
+
+
+
+
+static class BiomeColorsInitializer
+{
+public:
+	BiomeColorsInitializer(void)
+	{
+		// Reset all colors to gray:
+		for (size_t i = 0; i < ARRAYCOUNT(biomeToColor); i++)
+		{
+			biomeToColor[i] = 0x7f;
+		}
+
+		// Set known biomes to their colors:
+		for (size_t i = 0; i < ARRAYCOUNT(biomeColors); i++)
+		{
+			uchar * color = &biomeToColor[4 * biomeColors[i].m_Biome];
+			color[0] = biomeColors[i].m_Color[2];
+			color[1] = biomeColors[i].m_Color[1];
+			color[2] = biomeColors[i].m_Color[0];
+			color[3] = 0xff;
+		}
+	}
+} biomeColorInitializer;
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// BiomeView:
+
 BiomeView::BiomeView(QWidget * parent) :
 	super(parent),
 	m_X(0),
@@ -40,7 +150,7 @@ BiomeView::BiomeView(QWidget * parent) :
 	redraw();
 
 	// Add a chunk-update callback mechanism:
-	connect(&m_Cache, SIGNAL(chunkAvailable(int, int)), this, SLOT(chunkAvailable(int, int)));
+	connect(&m_Cache, SIGNAL(regionAvailable(int, int)), this, SLOT(regionAvailable(int, int)));
 
 	// Allow mouse and keyboard interaction:
 	setFocusPolicy(Qt::StrongFocus);
@@ -143,9 +253,15 @@ void BiomeView::redraw()
 
 
 
-void BiomeView::chunkAvailable(int a_ChunkX, int a_ChunkZ)
+void BiomeView::regionAvailable(int a_RegionX, int a_RegionZ)
 {
-	drawChunk(a_ChunkX, a_ChunkZ);
+	for (int z = 0; z < 32; z++)
+	{
+		for (int x = 0; x < 32; x++)
+		{
+			drawChunk(a_RegionX * 32 + x, a_RegionZ * 32 + z);
+		}
+	}
 	update();
 }
 
@@ -175,8 +291,11 @@ void BiomeView::drawChunk(int a_ChunkX, int a_ChunkZ)
 		return;
 	}
 
-	//fetch the chunk:
-	ChunkPtr chunk = m_Cache.fetch(a_ChunkX, a_ChunkZ);
+	// Fetch the region:
+	int regionX;
+	int regionZ;
+	Region::chunkToRegion(a_ChunkX, a_ChunkZ, regionX, regionZ);
+	RegionPtr region = m_Cache.fetch(regionX, regionZ);
 
 	// Figure out where on the screen this chunk should be drawn:
 	// first find the center chunk
@@ -194,11 +313,10 @@ void BiomeView::drawChunk(int a_ChunkX, int a_ChunkZ)
 	centerx += (a_ChunkX - centerchunkx) * chunksize;
 	centery += (a_ChunkZ - centerchunkz) * chunksize;
 
-	int srcoffset = 0;
 	uchar * bits = m_Image.bits();
 	int imgstride = m_Image.bytesPerLine();
 
-	int skipx = 0,skipy = 0;
+	int skipx = 0, skipy = 0;
 	int blockwidth = chunksize, blockheight = chunksize;
 	// now if we're off the screen we need to crop
 	if (centerx < 0)
@@ -227,29 +345,52 @@ void BiomeView::drawChunk(int a_ChunkX, int a_ChunkZ)
 	int imgoffset = centerx * 4 + centery * imgstride;
 
 	// If the chunk is valid, use its data; otherwise use the empty placeholder:
-	const uchar * src = m_EmptyChunkImage;
-	if (chunk.get() != nullptr)
+	const short * src = m_EmptyChunkBiomes;
+	if (region.get() != nullptr)
 	{
-		src = chunk->getImage();
+		int relChunkX = a_ChunkX - regionX * 32;
+		int relChunkZ = a_ChunkZ - regionZ * 32;
+		Chunk & chunk = region->getRelChunk(relChunkX, relChunkZ);
+		if (chunk.isValid())
+		{
+			src = chunk.getBiomes();
+		}
 	}
 
-	// Blit or scale-blit the image:
+	// Scale-blit the image:
 	for (int z = skipy; z < blockheight; z++, imgoffset += imgstride)
 	{
-		srcoffset = floor((double)z / m_Zoom) * 16 * 4;
-		if (m_Zoom == 1.0)
-		{
-			memcpy(bits + imgoffset, src + srcoffset + skipx * 4, (blockwidth - skipx) * 4);
-		}
-		else
+		size_t srcoffset = static_cast<size_t>(std::floor((double)z / m_Zoom)) * 16;
+		int imgxoffset = imgoffset;
+		for (int x = skipx; x < blockwidth; x++)
 		{
-			int xofs = 0;
-			for (int x = skipx; x < blockwidth; x++, xofs +=4)
+			short biome = src[srcoffset + static_cast<size_t>(std::floor((double)x / m_Zoom))];
+			const uchar * color;
+			if (biome < 0)
 			{
-				memcpy(bits + imgoffset + xofs, src + srcoffset + (int)floor((double)x / m_Zoom) * 4, 4);
+				static const uchar emptyBiome1[] = { 0x44, 0x44, 0x44, 0xff };
+				static const uchar emptyBiome2[] = { 0x88, 0x88, 0x88, 0xff };
+				color = ((x & 8) ^ (z & 8)) ? emptyBiome1 : emptyBiome2;
 			}
-		}
-	}
+			else
+			{
+				if (biome * 4 >= ARRAYCOUNT(biomeToColor))
+				{
+					static const uchar errorImage[] = { 0xff, 0x00, 0x00, 0xff };
+					color = errorImage;
+				}
+				else
+				{
+					color = biomeToColor + biome * 4;
+				}
+			}
+			bits[imgxoffset]     = color[0];
+			bits[imgxoffset + 1] = color[1];
+			bits[imgxoffset + 2] = color[2];
+			bits[imgxoffset + 3] = color[3];
+			imgxoffset += 4;
+		}  // for x
+	}  // for z
 }
 
 
@@ -317,11 +458,12 @@ void BiomeView::mouseMoveEvent(QMouseEvent * a_Event)
 	// Update the status bar info text:
 	int blockX = floor((a_Event->x() - width()  / 2) / m_Zoom + m_X);
 	int blockZ = floor((a_Event->y() - height() / 2) / m_Zoom + m_Z);
-	int chunkX, chunkZ;
-	int relX = blockX, relY, relZ = blockZ;
-	cChunkDef::AbsoluteToRelative(relX, relY, relZ, chunkX, chunkZ);
-	auto chunk = m_Cache.fetch(chunkX, chunkZ);
-	int biome = (chunk.get() != nullptr) ? chunk->getBiome(relX, relZ) : biInvalidBiome;
+	int regionX, regionZ;
+	Region::blockToRegion(blockX, blockZ, regionX, regionZ);
+	int relX = blockX - regionX * 512;
+	int relZ = blockZ - regionZ * 512;
+	auto region = m_Cache.fetch(regionX, regionZ);
+	int biome = (region.get() != nullptr) ? region->getRelBiome(relX, relZ) : biInvalidBiome;
 	emit hoverChanged(blockX, blockZ, biome);
 }
 
diff --git a/Tools/QtBiomeVisualiser/BiomeView.h b/Tools/QtBiomeVisualiser/BiomeView.h
index 40d8b96ae..cd9c7ead9 100644
--- a/Tools/QtBiomeVisualiser/BiomeView.h
+++ b/Tools/QtBiomeVisualiser/BiomeView.h
@@ -2,7 +2,7 @@
 
 #include <QWidget>
 #include <memory>
-#include "ChunkCache.h"
+#include "RegionCache.h"
 #include "ChunkSource.h"
 
 
@@ -51,8 +51,8 @@ public slots:
 	/** Redraw the entire widget area. */
 	void redraw();
 
-	/** A specified chunk has become available, redraw it. */
-	void chunkAvailable(int a_ChunkX, int a_ChunkZ);
+	/** A specified region has become available, redraw it. */
+	void regionAvailable(int a_RegionX, int a_RegionZ);
 
 	/** Reloads the current chunk source and redraws the entire workspace. */
 	void reload();
@@ -62,7 +62,7 @@ protected:
 	double m_Zoom;
 
 	/** Cache for the loaded chunk data. */
-	ChunkCache m_Cache;
+	RegionCache m_Cache;
 
 	/** The entire view's contents in an offscreen image. */
 	QImage m_Image;
@@ -79,6 +79,9 @@ protected:
 	/** Data used for rendering a chunk that hasn't been loaded yet */
 	uchar m_EmptyChunkImage[16 * 16 * 4];
 
+	/** Data placeholder for chunks that aren't valid. */
+	short m_EmptyChunkBiomes[16 * 16];
+
 
 	/** Draws the specified chunk into m_Image */
 	void drawChunk(int a_ChunkX, int a_ChunkZ);
diff --git a/Tools/QtBiomeVisualiser/ChunkCache.cpp b/Tools/QtBiomeVisualiser/ChunkCache.cpp
deleted file mode 100644
index bd8ade304..000000000
--- a/Tools/QtBiomeVisualiser/ChunkCache.cpp
+++ /dev/null
@@ -1,126 +0,0 @@
-#include "Globals.h"
-#include "ChunkCache.h"
-#include <QMutexLocker>
-#include <QThreadPool>
-#include "ChunkSource.h"
-#include "ChunkLoader.h"
-
-
-
-
-
-ChunkCache::ChunkCache(QObject * parent) :
-	super(parent)
-{
-	m_Cache.setMaxCost(1024 * 1024 * 1024);  // 1 GiB of memory for the cache
-}
-
-
-
-
-
-ChunkPtr ChunkCache::fetch(int a_ChunkX, int a_ChunkZ)
-{
-	// Retrieve from the cache:
-	quint32 hash = getChunkHash(a_ChunkX, a_ChunkZ);
-	ChunkPtr * res;
-	{
-		QMutexLocker lock(&m_Mtx);
-		res = m_Cache[hash];
-		// If succesful and chunk loaded, return the retrieved value:
-		if ((res != nullptr) && (*res)->isValid())
-		{
-			return *res;
-		}
-	}
-
-	// If the chunk is in cache but not valid, it means it has been already queued for rendering, do nothing now:
-	if (res != nullptr)
-	{
-		return ChunkPtr();
-	}
-
-	// There's no such item in the cache, create it now:
-	res = new ChunkPtr(new Chunk);
-	if (res == nullptr)
-	{
-		return ChunkPtr();
-	}
-	{
-		QMutexLocker lock(&m_Mtx);
-		m_Cache.insert(hash, res, sizeof(Chunk));
-	}
-
-	// Queue the chunk for rendering:
-	queueChunkRender(a_ChunkX, a_ChunkZ, *res);
-
-	// Return failure, the chunk is not yet rendered:
-	return ChunkPtr();
-}
-
-
-
-
-
-void ChunkCache::setChunkSource(std::shared_ptr<ChunkSource> a_ChunkSource)
-{
-	// Replace the chunk source:
-	m_ChunkSource = a_ChunkSource;
-
-	// Clear the cache:
-	QMutexLocker lock(&m_Mtx);
-	m_Cache.clear();
-}
-
-
-
-
-
-void ChunkCache::reload()
-{
-	assert(m_ChunkSource.get() != nullptr);
-
-	// Reload the chunk source:
-	m_ChunkSource->reload();
-
-	// Clear the cache:
-	QMutexLocker lock(&m_Mtx);
-	m_Cache.clear();
-}
-
-
-
-
-
-void ChunkCache::gotChunk(int a_ChunkX, int a_ChunkZ)
-{
-	emit chunkAvailable(a_ChunkX, a_ChunkZ);
-}
-
-
-
-
-
-quint32 ChunkCache::getChunkHash(int a_ChunkX, int a_ChunkZ)
-{
-	// Simply join the two coords into a single int
-	// The coords will never be larger than 16-bits, so we can do this safely
-	return (((static_cast<quint32>(a_ChunkX) & 0xffff) << 16) | (static_cast<quint32>(a_ChunkZ) & 0xffff));
-}
-
-
-
-
-
-void ChunkCache::queueChunkRender(int a_ChunkX, int a_ChunkZ, ChunkPtr & a_Chunk)
-{
-	// Create a new loader task:
-	ChunkLoader * loader = new ChunkLoader(a_ChunkX, a_ChunkZ, a_Chunk, m_ChunkSource);
-	connect(loader, SIGNAL(loaded(int, int)), this, SLOT(gotChunk(int, int)));
-
-	QThreadPool::globalInstance()->start(loader);
-}
-
-
-
-
diff --git a/Tools/QtBiomeVisualiser/ChunkLoader.cpp b/Tools/QtBiomeVisualiser/ChunkLoader.cpp
deleted file mode 100644
index 3d0123b23..000000000
--- a/Tools/QtBiomeVisualiser/ChunkLoader.cpp
+++ /dev/null
@@ -1,29 +0,0 @@
-#include "Globals.h"
-#include "ChunkLoader.h"
-#include "ChunkSource.h"
-
-
-
-
-
-ChunkLoader::ChunkLoader(int a_ChunkX, int a_ChunkZ, ChunkPtr a_Chunk, ChunkSourcePtr a_ChunkSource) :
-	m_ChunkX(a_ChunkX),
-	m_ChunkZ(a_ChunkZ),
-	m_Chunk(a_Chunk),
-	m_ChunkSource(a_ChunkSource)
-{
-}
-
-
-
-
-
-void ChunkLoader::run()
-{
-	m_ChunkSource->getChunkBiomes(m_ChunkX, m_ChunkZ, m_Chunk);
-	emit loaded(m_ChunkX, m_ChunkZ);
-}
-
-
-
-
diff --git a/Tools/QtBiomeVisualiser/ChunkLoader.h b/Tools/QtBiomeVisualiser/ChunkLoader.h
deleted file mode 100644
index e6eb80cbf..000000000
--- a/Tools/QtBiomeVisualiser/ChunkLoader.h
+++ /dev/null
@@ -1,54 +0,0 @@
-#pragma once
-
-#include <QObject>
-#include <QRunnable>
-#include <memory>
-
-
-
-
-#if (!defined(_MSC_VER) && (__cplusplus < 201103L))
-	// GCC in non-c++11 mode doesn't have the "override" keyword
-	#define override
-#endif
-
-
-
-
-
-// fwd:
-class Chunk;
-typedef std::shared_ptr<Chunk> ChunkPtr;
-
-class ChunkSource;
-typedef std::shared_ptr<ChunkSource> ChunkSourcePtr;
-
-
-
-
-
-class ChunkLoader :
-	public QObject,
-	public QRunnable
-{
-	Q_OBJECT
-
-public:
-	ChunkLoader(int a_ChunkX, int a_ChunkZ, ChunkPtr a_Chunk, ChunkSourcePtr a_ChunkSource);
-	virtual ~ChunkLoader() {}
-
-signals:
-	void loaded(int a_ChunkX, int a_ChunkZ);
-
-protected:
-	virtual void run() override;
-
-private:
-	int m_ChunkX, m_ChunkZ;
-	ChunkPtr m_Chunk;
-	ChunkSourcePtr m_ChunkSource;
-};
-
-
-
-
diff --git a/Tools/QtBiomeVisualiser/ChunkSource.cpp b/Tools/QtBiomeVisualiser/ChunkSource.cpp
index c3e29c0a2..d9660b886 100644
--- a/Tools/QtBiomeVisualiser/ChunkSource.cpp
+++ b/Tools/QtBiomeVisualiser/ChunkSource.cpp
@@ -24,14 +24,14 @@ BioGenSource::BioGenSource(cIniFilePtr a_IniFile) :
 
 
 
-void BioGenSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChunk)
+void BioGenSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, Chunk & a_DestChunk)
 {
 	cChunkDef::BiomeMap biomes;
 	{
 		QMutexLocker lock(&m_Mtx);
 		m_BiomeGen->GenBiomes(a_ChunkX, a_ChunkZ, biomes);
 	}
-	a_DestChunk->setBiomes(biomes);
+	a_DestChunk.setBiomes(biomes);
 }
 
 
@@ -160,7 +160,7 @@ AnvilSource::AnvilSource(QString a_WorldRegionFolder) :
 
 
 
-void AnvilSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChunk)
+void AnvilSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, Chunk & a_DestChunk)
 {
 	// Load the compressed data:
 	AString compressedChunkData = getCompressedChunkData(a_ChunkX, a_ChunkZ);
@@ -200,7 +200,7 @@ void AnvilSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChun
 		{
 			biomeMap[i] = (EMCSBiome)GetBEInt(beBiomes + 4 * i);
 		}
-		a_DestChunk->setBiomes(biomeMap);
+		a_DestChunk.setBiomes(biomeMap);
 		return;
 	}
 
@@ -216,7 +216,7 @@ void AnvilSource::getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChun
 	{
 		biomeMap[i] = EMCSBiome(vanillaBiomes[i]);
 	}
-	a_DestChunk->setBiomes(biomeMap);
+	a_DestChunk.setBiomes(biomeMap);
 }
 
 
diff --git a/Tools/QtBiomeVisualiser/ChunkSource.h b/Tools/QtBiomeVisualiser/ChunkSource.h
index 65b2c3449..a6bc3849b 100644
--- a/Tools/QtBiomeVisualiser/ChunkSource.h
+++ b/Tools/QtBiomeVisualiser/ChunkSource.h
@@ -26,7 +26,7 @@ public:
 
 	/** Fills the a_DestChunk with the biomes for the specified coords.
 	It is expected to be thread-safe and re-entrant. Usually QThread::idealThreadCount() threads are used. */
-	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChunk) = 0;
+	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, Chunk & a_DestChunk) = 0;
 
 	/** Forces a fresh reload of the source. Useful mainly for the generator, whose underlying definition file may have been changed. */
 	virtual void reload() = 0;
@@ -45,7 +45,7 @@ public:
 	BioGenSource(cIniFilePtr a_IniFile);
 
 	// ChunkSource overrides:
-	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChunk) override;
+	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, Chunk & a_DestChunk) override;
 	virtual void reload(void) override;
 
 protected:
@@ -70,7 +70,7 @@ public:
 	AnvilSource(QString a_WorldRegionFolder);
 
 	// ChunkSource overrides:
-	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, ChunkPtr a_DestChunk) override;
+	virtual void getChunkBiomes(int a_ChunkX, int a_ChunkZ, Chunk & a_DestChunk) override;
 	virtual void reload() override;
 
 protected:
diff --git a/Tools/QtBiomeVisualiser/MainWindow.cpp b/Tools/QtBiomeVisualiser/MainWindow.cpp
index 7853d768e..dc26a32c7 100644
--- a/Tools/QtBiomeVisualiser/MainWindow.cpp
+++ b/Tools/QtBiomeVisualiser/MainWindow.cpp
@@ -8,8 +8,8 @@
 #include <QSettings>
 #include <QDirIterator>
 #include <QStatusBar>
-#include "src/IniFile.h"
 #include "ChunkSource.h"
+#include "src/IniFile.h"
 #include "src/Generating/BioGen.h"
 #include "src/StringCompression.h"
 #include "src/WorldStorage/FastNBT.h"
diff --git a/Tools/QtBiomeVisualiser/QtBiomeVisualiser.pro b/Tools/QtBiomeVisualiser/QtBiomeVisualiser.pro
index f3a5255fb..4cff9c90f 100644
--- a/Tools/QtBiomeVisualiser/QtBiomeVisualiser.pro
+++ b/Tools/QtBiomeVisualiser/QtBiomeVisualiser.pro
@@ -26,9 +26,6 @@ SOURCES +=\
     ../../src/OSSupport/CriticalSection.cpp \
     ../../src/OSSupport/IsThread.cpp \
     ../../src/BiomeDef.cpp \
-    ChunkCache.cpp \
-    ChunkSource.cpp \
-    ChunkLoader.cpp \
     ../../src/StringCompression.cpp \
     ../../src/WorldStorage/FastNBT.cpp \
     ../../lib/zlib/adler32.c \
@@ -48,7 +45,11 @@ SOURCES +=\
     ../../lib/zlib/zutil.c \
     GeneratorSetup.cpp \
     QtBiomeVisualiser.cpp \
-    QtChunk.cpp
+    QtChunk.cpp \
+    RegionCache.cpp \
+    Region.cpp \
+    ChunkSource.cpp \
+    RegionLoader.cpp
 
 HEADERS  += MainWindow.h \
 		Globals.h \
@@ -64,9 +65,6 @@ HEADERS  += MainWindow.h \
     ../../src/OSSupport/CriticalSection.h \
     ../../src/OSSupport/IsThread.h \
     ../../src/BiomeDef.h \
-    ChunkCache.h \
-    ChunkSource.h \
-    ChunkLoader.h \
     ../../src/StringCompression.h \
     ../../src/WorldStorage/FastNBT.h \
     ../../lib/zlib/crc32.h \
@@ -81,7 +79,11 @@ HEADERS  += MainWindow.h \
     ../../lib/zlib/zlib.h \
     ../../lib/zlib/zutil.h \
     GeneratorSetup.h \
-    QtChunk.h
+    QtChunk.h \
+    RegionCache.h \
+    Region.h \
+    ChunkSource.h \
+    RegionLoader.h
 
 INCLUDEPATH += $$_PRO_FILE_PWD_ \
 	$$_PRO_FILE_PWD_/../../lib \
diff --git a/Tools/QtBiomeVisualiser/QtChunk.cpp b/Tools/QtBiomeVisualiser/QtChunk.cpp
index 031aa3654..f201ef220 100644
--- a/Tools/QtBiomeVisualiser/QtChunk.cpp
+++ b/Tools/QtBiomeVisualiser/QtChunk.cpp
@@ -5,138 +5,6 @@
 
 
 
-/** Map for converting biome values to colors. Initialized from biomeColors[]. */
-static uchar biomeToColor[256 * 4];
-
-/** Map for converting biome values to colors. Used to initialize biomeToColor[].*/
-static struct
-{
-	EMCSBiome m_Biome;
-	uchar m_Color[3];
-} biomeColors[] =
-{
-	{ biOcean,                { 0x00, 0x00, 0x70 }, },
-	{ biPlains,               { 0x8d, 0xb3, 0x60 }, },
-	{ biDesert,               { 0xfa, 0x94, 0x18 }, },
-	{ biExtremeHills,         { 0x60, 0x60, 0x60 }, },
-	{ biForest,               { 0x05, 0x66, 0x21 }, },
-	{ biTaiga,                { 0x0b, 0x66, 0x59 }, },
-	{ biSwampland,            { 0x2f, 0xff, 0xda }, },
-	{ biRiver,                { 0x30, 0x30, 0xaf }, },
-	{ biHell,                 { 0x7f, 0x00, 0x00 }, },
-	{ biSky,                  { 0x00, 0x7f, 0xff }, },
-	{ biFrozenOcean,          { 0xa0, 0xa0, 0xdf }, },
-	{ biFrozenRiver,          { 0xa0, 0xa0, 0xff }, },
-	{ biIcePlains,            { 0xff, 0xff, 0xff }, },
-	{ biIceMountains,         { 0xa0, 0xa0, 0xa0 }, },
-	{ biMushroomIsland,       { 0xff, 0x00, 0xff }, },
-	{ biMushroomShore,        { 0xa0, 0x00, 0xff }, },
-	{ biBeach,                { 0xfa, 0xde, 0x55 }, },
-	{ biDesertHills,          { 0xd2, 0x5f, 0x12 }, },
-	{ biForestHills,          { 0x22, 0x55, 0x1c }, },
-	{ biTaigaHills,           { 0x16, 0x39, 0x33 }, },
-	{ biExtremeHillsEdge,     { 0x7f, 0x8f, 0x7f }, },
-	{ biJungle,               { 0x53, 0x7b, 0x09 }, },
-	{ biJungleHills,          { 0x2c, 0x42, 0x05 }, },
-
-	{ biJungleEdge,           { 0x62, 0x8b, 0x17 }, },
-	{ biDeepOcean,            { 0x00, 0x00, 0x30 },	},
-	{ biStoneBeach,           { 0xa2, 0xa2, 0x84 },	},
-	{ biColdBeach,            { 0xfa, 0xf0, 0xc0 },	},
-	{ biBirchForest,          { 0x30, 0x74, 0x44 },	},
-	{ biBirchForestHills,     { 0x1f, 0x5f, 0x32 },	},
-	{ biRoofedForest,         { 0x40, 0x51, 0x1a },	},
-	{ biColdTaiga,            { 0x31, 0x55, 0x4a },	},
-	{ biColdTaigaHills,       { 0x59, 0x7d, 0x72 },	},
-	{ biMegaTaiga,            { 0x59, 0x66, 0x51 },	},
-	{ biMegaTaigaHills,       { 0x59, 0x66, 0x59 },	},
-	{ biExtremeHillsPlus,     { 0x50, 0x70, 0x50 },	},
-	{ biSavanna,              { 0xbd, 0xb2, 0x5f },	},
-	{ biSavannaPlateau,       { 0xa7, 0x9d, 0x64 },	},
-	{ biMesa,                 { 0xd9, 0x45, 0x15 },	},
-	{ biMesaPlateauF,         { 0xb0, 0x97, 0x65 },	},
-	{ biMesaPlateau,          { 0xca, 0x8c, 0x65 },	},
-
-	// M variants:
-	{ biSunflowerPlains,      { 0xb5, 0xdb, 0x88 }, },
-	{ biDesertM,              { 0xff, 0xbc, 0x40 }, },
-	{ biExtremeHillsM,        { 0x88, 0x88, 0x88 }, },
-	{ biFlowerForest,         { 0x2d, 0x8e, 0x49 }, },
-	{ biTaigaM,               { 0x33, 0x8e, 0x81 }, },
-	{ biSwamplandM,           { 0x07, 0xf9, 0xb2 }, },
-	{ biIcePlainsSpikes,      { 0xb4, 0xdc, 0xdc }, },
-	{ biJungleM,              { 0x7b, 0xa3, 0x31 }, },
-	{ biJungleEdgeM,          { 0x62, 0x8b, 0x17 }, },
-	{ biBirchForestM,         { 0x58, 0x9c, 0x6c }, },
-	{ biBirchForestHillsM,    { 0x47, 0x87, 0x5a }, },
-	{ biRoofedForestM,        { 0x68, 0x79, 0x42 }, },
-	{ biColdTaigaM,           { 0x24, 0x3f, 0x36 }, },
-	{ biMegaSpruceTaiga,      { 0x45, 0x4f, 0x3e }, },
-	{ biMegaSpruceTaigaHills, { 0x45, 0x4f, 0x4e }, },
-	{ biExtremeHillsPlusM,    { 0x78, 0x98, 0x78 }, },
-	{ biSavannaM,             { 0xe5, 0xda, 0x87 }, },
-	{ biSavannaPlateauM,      { 0xa7, 0x9d, 0x74 }, },
-	{ biMesaBryce,            { 0xff, 0x6d, 0x3d }, },
-	{ biMesaPlateauFM,        { 0xd8, 0xbf, 0x8d }, },
-	{ biMesaPlateauM,         { 0xf2, 0xb4, 0x8d }, },
-} ;
-
-
-
-
-
-static class BiomeColorsInitializer
-{
-public:
-	BiomeColorsInitializer(void)
-	{
-		// Reset all colors to gray:
-		for (size_t i = 0; i < ARRAYCOUNT(biomeToColor); i++)
-		{
-			biomeToColor[i] = 0x7f;
-		}
-
-		// Set known biomes to their colors:
-		for (size_t i = 0; i < ARRAYCOUNT(biomeColors); i++)
-		{
-			uchar * color = &biomeToColor[4 * biomeColors[i].m_Biome];
-			color[0] = biomeColors[i].m_Color[2];
-			color[1] = biomeColors[i].m_Color[1];
-			color[2] = biomeColors[i].m_Color[0];
-			color[3] = 0xff;
-		}
-	}
-} biomeColorInitializer;
-
-
-
-
-
-/** Converts biomes in an array into the chunk image data. */
-static void biomesToImage(const cChunkDef::BiomeMap & a_Biomes, Chunk::Image & a_Image)
-{
-	// Make sure the two arrays are of the same size, compile-time.
-	// Note that a_Image is actually 4 items per pixel, so the array is 4 times bigger:
-	static const char Check1[4 * ARRAYCOUNT(a_Biomes) - ARRAYCOUNT(a_Image)      + 1] = {};
-	static const char Check2[ARRAYCOUNT(a_Image)      - 4 * ARRAYCOUNT(a_Biomes) + 1] = {};
-
-	// Convert the biomes into color:
-	for (size_t i = 0; i < ARRAYCOUNT(a_Biomes); i++)
-	{
-		a_Image[4 * i + 0] = biomeToColor[4 * a_Biomes[i] + 0];
-		a_Image[4 * i + 1] = biomeToColor[4 * a_Biomes[i] + 1];
-		a_Image[4 * i + 2] = biomeToColor[4 * a_Biomes[i] + 2];
-		a_Image[4 * i + 3] = biomeToColor[4 * a_Biomes[i] + 3];
-	}
-}
-
-
-
-
-
-////////////////////////////////////////////////////////////////////////////////
-// Chunk:
-
 Chunk::Chunk() :
 	m_IsValid(false)
 {
@@ -146,20 +14,12 @@ Chunk::Chunk() :
 
 
 
-const uchar * Chunk::getImage(void) const
-{
-	ASSERT(m_IsValid);
-	return m_Image;
-}
-
-
-
-
-
 void Chunk::setBiomes(const cChunkDef::BiomeMap & a_Biomes)
 {
-	memcpy(m_Biomes, a_Biomes, sizeof(m_Biomes));
-	renderBiomes();
+	for (size_t idx = 0; idx < ARRAYCOUNT(a_Biomes); ++idx)
+	{
+		m_Biomes[idx] = static_cast<short>(a_Biomes[idx]);
+	}
 	m_IsValid = true;
 }
 
@@ -173,16 +33,7 @@ EMCSBiome Chunk::getBiome(int a_RelX, int a_RelZ)
 	{
 		return biInvalidBiome;
 	}
-	return cChunkDef::GetBiome(m_Biomes, a_RelX, a_RelZ);
-}
-
-
-
-
-
-void Chunk::renderBiomes()
-{
-	biomesToImage(m_Biomes, m_Image);
+	return static_cast<EMCSBiome>(m_Biomes[a_RelX + 16 * a_RelZ]);
 }
 
 
diff --git a/Tools/QtBiomeVisualiser/QtChunk.h b/Tools/QtBiomeVisualiser/QtChunk.h
index 74321577a..d806d18bb 100644
--- a/Tools/QtBiomeVisualiser/QtChunk.h
+++ b/Tools/QtBiomeVisualiser/QtChunk.h
@@ -18,9 +18,6 @@ public:
 	/** Returns true iff the chunk data is valid - loaded or generated. */
 	bool isValid(void) const { return m_IsValid; }
 
-	/** Returns the image of the chunk's biomes. Assumes that the chunk is valid. */
-	const uchar * getImage(void) const;
-
 	/** Sets the biomes to m_Biomes and renders them into m_Image. */
 	void setBiomes(const cChunkDef::BiomeMap & a_Biomes);
 
@@ -28,19 +25,16 @@ public:
 	Coords must be valid inside this chunk. */
 	EMCSBiome getBiome(int a_RelX, int a_RelZ);
 
+	/** Returns the raw biome data for this chunk. */
+	const short * getBiomes(void) const { return m_Biomes; }
+
 protected:
 	/** Flag that specifies if the chunk data is valid - loaded or generated. */
 	bool m_IsValid;
 
-	/** Cached rendered image of this chunk's biomes. Updated in render(). */
-	Image m_Image;
-
-	/** Biomes comprising the chunk, in the X + 16 * Z ordering. */
-	cChunkDef::BiomeMap m_Biomes;
-
-
-	/** Renders biomes from m_Biomes into m_Image. */
-	void renderBiomes();
+	/** Biomes comprising the chunk, in the X + 16 * Z ordering.
+	Typed as short to save on memory, converted automatically when needed. */
+	short m_Biomes[16 * 16];
 };
 
 typedef std::shared_ptr<Chunk> ChunkPtr;
diff --git a/Tools/QtBiomeVisualiser/Region.cpp b/Tools/QtBiomeVisualiser/Region.cpp
new file mode 100644
index 000000000..d8a0a2f76
--- /dev/null
+++ b/Tools/QtBiomeVisualiser/Region.cpp
@@ -0,0 +1,72 @@
+
+#include "Globals.h"
+#include "Region.h"
+
+
+
+
+
+Region::Region()
+{
+}
+
+
+
+
+
+Chunk & Region::getRelChunk(int a_RelChunkX, int a_RelChunkZ)
+{
+		ASSERT(a_RelChunkX >= 0);
+		ASSERT(a_RelChunkZ >= 0);
+		ASSERT(a_RelChunkX < 32);
+		ASSERT(a_RelChunkZ < 32);
+
+		return m_Chunks[a_RelChunkX + a_RelChunkZ * 32];
+}
+
+
+
+
+
+int Region::getRelBiome(int a_RelBlockX, int a_RelBlockZ)
+{
+	ASSERT(a_RelBlockX >= 0);
+	ASSERT(a_RelBlockZ >= 0);
+	ASSERT(a_RelBlockX < 512);
+	ASSERT(a_RelBlockZ < 512);
+
+	int chunkX = a_RelBlockX / 16;
+	int chunkZ = a_RelBlockZ / 16;
+	Chunk & chunk = m_Chunks[chunkX + 32 * chunkZ];
+	if (chunk.isValid())
+	{
+		return chunk.getBiome(a_RelBlockX - 16 * chunkX, a_RelBlockZ - 16 * chunkZ);
+	}
+	else
+	{
+		return biInvalidBiome;
+	}
+}
+
+
+
+
+void Region::blockToRegion(int a_BlockX, int a_BlockZ, int & a_RegionX, int & a_RegionZ)
+{
+	a_RegionX = static_cast<int>(std::floor(static_cast<float>(a_BlockX) / 512));
+	a_RegionZ = static_cast<int>(std::floor(static_cast<float>(a_BlockZ) / 512));
+}
+
+
+
+
+
+void Region::chunkToRegion(int a_ChunkX, int a_ChunkZ, int & a_RegionX, int & a_RegionZ)
+{
+	a_RegionX = static_cast<int>(std::floor(static_cast<float>(a_ChunkX) / 32));
+	a_RegionZ = static_cast<int>(std::floor(static_cast<float>(a_ChunkZ) / 32));
+}
+
+
+
+
diff --git a/Tools/QtBiomeVisualiser/Region.h b/Tools/QtBiomeVisualiser/Region.h
new file mode 100644
index 000000000..863c0ac02
--- /dev/null
+++ b/Tools/QtBiomeVisualiser/Region.h
@@ -0,0 +1,46 @@
+#pragma once
+
+#include "QtChunk.h"
+
+
+
+
+
+class Region
+{
+public:
+	Region();
+
+	/** Retrieves the chunk with the specified relative coords. */
+	Chunk & getRelChunk(int a_RelChunkX, int a_RelChunkZ);
+
+	/** Returns true iff the chunk data for all chunks has been loaded.
+	This doesn't mean that all the chunks are valid, only that the entire region has been processed and should
+	be displayed. */
+	bool isValid(void) const { return m_IsValid; }
+
+	/** Returns the biome in the block coords relative to this region.
+	Returns biInvalidBiome if the underlying chunk is not valid. */
+	int getRelBiome(int a_RelBlockX, int a_RelBlockZ);
+
+	/** Converts block coordinates into region coordinates. */
+	static void blockToRegion(int a_BlockX, int a_BlockZ, int & a_RegionX, int & a_RegionZ);
+
+	/** Converts chunk coordinates into region coordinates. */
+	static void chunkToRegion(int a_ChunkX, int a_ChunkZ, int & a_RegionX, int & a_RegionZ);
+
+protected:
+	friend class RegionLoader;
+
+
+	Chunk m_Chunks[32 * 32];
+
+	/** True iff the data for all the chunks has been loaded.
+	This doesn't mean that all the chunks are valid, only that the entire region has been processed and should
+	be displayed. */
+	bool m_IsValid;
+};
+
+
+
+
diff --git a/Tools/QtBiomeVisualiser/RegionCache.cpp b/Tools/QtBiomeVisualiser/RegionCache.cpp
new file mode 100644
index 000000000..e46fd222a
--- /dev/null
+++ b/Tools/QtBiomeVisualiser/RegionCache.cpp
@@ -0,0 +1,138 @@
+#include "Globals.h"
+#include "RegionCache.h"
+#include <QMutexLocker>
+#include <QThreadPool>
+#include "ChunkSource.h"
+#include "RegionLoader.h"
+#include "Region.h"
+
+
+
+
+
+RegionCache::RegionCache(QObject * parent) :
+	super(parent)
+{
+	m_Cache.setMaxCost(1024 * 1024 * 1024);  // 1 GiB of memory for the cache
+}
+
+
+
+
+
+RegionPtr RegionCache::fetch(int a_RegionX, int a_RegionZ)
+{
+	// Retrieve from the cache:
+	quint32 hash = getRegionHash(a_RegionX, a_RegionZ);
+	RegionPtr * res;
+	{
+		QMutexLocker lock(&m_Mtx);
+		res = m_Cache[hash];
+		// If succesful and region loaded, return the retrieved value:
+		if ((res != nullptr) && (*res)->isValid())
+		{
+			return *res;
+		}
+	}
+
+	// If the region is in cache but not valid, it means it has been already queued for rendering, do nothing now:
+	if (res != nullptr)
+	{
+		return RegionPtr(nullptr);
+	}
+
+	// There's no such item in the cache, create it now:
+	try
+	{
+		res = new RegionPtr(new Region);
+	}
+	catch (const std::bad_alloc &)
+	{
+		/* Allocation failed (32-bit process hit the 2 GiB barrier?)
+		This may happen even with the cache set to 1 GiB, because it contains shared ptrs and so they may be
+		held by another place in the code even when they are removed from cache.
+		*/
+		return RegionPtr(nullptr);
+	}
+	if (res == nullptr)
+	{
+		return RegionPtr(nullptr);
+	}
+	{
+		QMutexLocker lock(&m_Mtx);
+		m_Cache.insert(hash, res, sizeof(Region));
+	}
+
+	// Queue the region for rendering:
+	queueRegionRender(a_RegionX, a_RegionZ, *res);
+
+	// Return failure, the region is not yet rendered:
+	return RegionPtr(nullptr);
+}
+
+
+
+
+
+void RegionCache::setChunkSource(std::shared_ptr<ChunkSource> a_ChunkSource)
+{
+	// Replace the chunk source:
+	m_ChunkSource = a_ChunkSource;
+
+	// Clear the cache:
+	QMutexLocker lock(&m_Mtx);
+	m_Cache.clear();
+}
+
+
+
+
+
+void RegionCache::reload()
+{
+	assert(m_ChunkSource.get() != nullptr);
+
+	// Reload the chunk source:
+	m_ChunkSource->reload();
+
+	// Clear the cache:
+	QMutexLocker lock(&m_Mtx);
+	m_Cache.clear();
+}
+
+
+
+
+
+void RegionCache::gotRegion(int a_RegionX, int a_RegionZ)
+{
+	emit regionAvailable(a_RegionX, a_RegionZ);
+}
+
+
+
+
+
+quint32 RegionCache::getRegionHash(int a_RegionX, int a_RegionZ)
+{
+	// Simply join the two coords into a single int
+	// The coords will never be larger than 16-bits, so we can do this safely
+	return (((static_cast<quint32>(a_RegionX) & 0xffff) << 16) | (static_cast<quint32>(a_RegionZ) & 0xffff));
+}
+
+
+
+
+
+void RegionCache::queueRegionRender(int a_RegionX, int a_RegionZ, RegionPtr & a_Region)
+{
+	// Create a new loader task:
+	RegionLoader * loader = new RegionLoader(a_RegionX, a_RegionZ, a_Region, m_ChunkSource);
+	connect(loader, SIGNAL(loaded(int, int)), this, SLOT(gotRegion(int, int)));
+
+	QThreadPool::globalInstance()->start(loader);
+}
+
+
+
+
diff --git a/Tools/QtBiomeVisualiser/ChunkCache.h b/Tools/QtBiomeVisualiser/RegionCache.h
index 8d198f02f..c343e4ba9 100644
--- a/Tools/QtBiomeVisualiser/ChunkCache.h
+++ b/Tools/QtBiomeVisualiser/RegionCache.h
@@ -9,8 +9,9 @@
 
 
 
-class Chunk;
-typedef std::shared_ptr<Chunk> ChunkPtr;
+// fwd:
+class Region;
+typedef std::shared_ptr<Region> RegionPtr;
 
 class ChunkSource;
 
@@ -18,19 +19,19 @@ class ChunkSource;
 
 
 
-/** Caches chunk data for reuse */
-class ChunkCache :
+/** Caches regions' chunk data for reuse */
+class RegionCache :
 	public QObject
 {
 	typedef QObject super;
 	Q_OBJECT
 
 public:
-	explicit ChunkCache(QObject * parent = NULL);
+	explicit RegionCache(QObject * parent = NULL);
 
-	/** Retrieves the specified chunk from the cache.
-	Only returns valid chunks; if the chunk is invalid, queues it for rendering and returns an empty ptr. */
-	ChunkPtr fetch(int a_ChunkX, int a_ChunkZ);
+	/** Retrieves the specified region from the cache.
+	Only returns valid regions; if the region is invalid, queues it for rendering and returns an empty ptr. */
+	RegionPtr fetch(int a_RegionX, int a_RegionZ);
 
 	/** Replaces the chunk source used by the biome view to get the chunk biome data.
 	The cache is then invalidated. */
@@ -43,16 +44,16 @@ public:
 	void reload();
 
 signals:
-	void chunkAvailable(int a_ChunkX, int a_ChunkZ);
+	void regionAvailable(int a_RegionX, int a_RegionZ);
 
 protected slots:
-	void gotChunk(int a_ChunkX, int a_ChunkZ);
+	void gotRegion(int a_RegionX, int a_RegionZ);
 
 protected:
 	/** The cache of the chunks */
-	QCache<quint32, ChunkPtr> m_Cache;
+	QCache<quint32, RegionPtr> m_Cache;
 
-	/** Locks te cache against multithreaded access */
+	/** Locks the cache against multithreaded access */
 	QMutex m_Mtx;
 
 	/** The source used to get the biome data. */
@@ -60,10 +61,10 @@ protected:
 
 
 	/** Returns the hash used by the chunk in the cache */
-	quint32 getChunkHash(int a_ChunkX, int a_ChunkZ);
+	quint32 getRegionHash(int a_RegionX, int a_RegionZ);
 
-	/** Queues the specified chunk for rendering by m_ChunkSource. */
-	void queueChunkRender(int a_ChunkX, int a_ChunkZ, ChunkPtr & a_Chunk);
+	/** Queues the specified region for rendering by m_RegionSource. */
+	void queueRegionRender(int a_RegionX, int a_RegionZ, RegionPtr & a_Region);
 };
 
 
diff --git a/Tools/QtBiomeVisualiser/RegionLoader.cpp b/Tools/QtBiomeVisualiser/RegionLoader.cpp
new file mode 100644
index 000000000..771c1bbac
--- /dev/null
+++ b/Tools/QtBiomeVisualiser/RegionLoader.cpp
@@ -0,0 +1,39 @@
+#include "Globals.h"
+#include "RegionLoader.h"
+#include "ChunkSource.h"
+#include "Region.h"
+
+
+
+
+
+RegionLoader::RegionLoader(int a_RegionX, int a_RegionZ, RegionPtr a_Region, ChunkSourcePtr a_ChunkSource) :
+	m_RegionX(a_RegionX),
+	m_RegionZ(a_RegionZ),
+	m_Region(a_Region),
+	m_ChunkSource(a_ChunkSource)
+{
+}
+
+
+
+
+
+void RegionLoader::run()
+{
+	// Load all the chunks in this region:
+	for (int z = 0; z < 32; z++)
+	{
+		for (int x = 0; x < 32; x++)
+		{
+			m_ChunkSource->getChunkBiomes(m_RegionX * 32 + x, m_RegionZ * 32 + z, m_Region->getRelChunk(x, z));
+		}
+	}
+	m_Region->m_IsValid = true;
+
+	emit loaded(m_RegionX, m_RegionZ);
+}
+
+
+
+
diff --git a/Tools/QtBiomeVisualiser/RegionLoader.h b/Tools/QtBiomeVisualiser/RegionLoader.h
new file mode 100644
index 000000000..5a993f5ca
--- /dev/null
+++ b/Tools/QtBiomeVisualiser/RegionLoader.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include <QObject>
+#include <QRunnable>
+#include <memory>
+
+
+
+
+// fwd:
+class Region;
+typedef std::shared_ptr<Region> RegionPtr;
+
+class ChunkSource;
+typedef std::shared_ptr<ChunkSource> ChunkSourcePtr;
+
+
+
+
+
+class RegionLoader :
+	public QObject,
+	public QRunnable
+{
+	Q_OBJECT
+
+public:
+	RegionLoader(int a_RegionX, int a_RegionZ, RegionPtr a_Region, ChunkSourcePtr a_ChunkSource);
+	virtual ~RegionLoader() {}
+
+signals:
+	void loaded(int a_RegionX, int a_RegionZ);
+
+protected:
+	virtual void run() override;
+
+private:
+	/** Coords of the region to be loaded. */
+	int m_RegionX, m_RegionZ;
+
+	/** The region to be loaded. */
+	RegionPtr m_Region;
+
+	/** The chunk source to be used for individual chunks within the region. */
+	ChunkSourcePtr m_ChunkSource;
+};
+
+
+
+