Merge

--HG--
branch : product-engine

9 files changed, 525 insertions, 180 deletions

diff --git a/indra/llimage/CMakeLists.txt b/indra/llimage/CMakeLists.txt
index 0635ddd5f5..22be4078a1 100644
--- a/indra/llimage/CMakeLists.txt
+++ b/indra/llimage/CMakeLists.txt
@@ -3,6 +3,7 @@
 project(llimage)
 
 include(00-Common)
+include(LLAddBuildTest)
 include(LLCommon)
 include(LLImage)
 include(LLMath)
@@ -59,3 +60,6 @@ target_link_libraries(llimage
     ${PNG_LIBRARIES}
     ${ZLIB_LIBRARIES}
     )
+
+# Add tests
+#ADD_BUILD_TEST(llimageworker llimage)
diff --git a/indra/llimage/llimage.cpp b/indra/llimage/llimage.cpp
index 9bbc55509d..575ad5363d 100644
--- a/indra/llimage/llimage.cpp
+++ b/indra/llimage/llimage.cpp
@@ -55,13 +55,9 @@ std::string LLImage::sLastErrorMessage;
 LLMutex* LLImage::sMutex = NULL;
 
 //static
-void LLImage::initClass(LLWorkerThread* workerthread)
+void LLImage::initClass()
 {
 	sMutex = new LLMutex(NULL);
-	if (workerthread)
-	{
-		LLImageWorker::initImageWorker(workerthread);
-	}
 	LLImageJ2C::openDSO();
 }
 
@@ -69,7 +65,6 @@ void LLImage::initClass(LLWorkerThread* workerthread)
 void LLImage::cleanupClass()
 {
 	LLImageJ2C::closeDSO();
-	LLImageWorker::cleanupImageWorker();
 	delete sMutex;
 	sMutex = NULL;
 }
@@ -316,6 +311,21 @@ void LLImageRaw::deleteData()
 	LLImageBase::deleteData();
 }
 
+void LLImageRaw::setDataAndSize(U8 *data, S32 width, S32 height, S8 components) 
+{ 
+	if(data == getData())
+	{
+		return ;
+	}
+
+	deleteData();
+
+	LLImageBase::setSize(width, height, components) ;
+	LLImageBase::setDataAndSize(data, width * height * components) ;
+	
+	sGlobalRawMemory += getDataSize();
+}
+
 BOOL LLImageRaw::resize(U16 width, U16 height, S8 components)
 {
 	if ((getWidth() == width) && (getHeight() == height) && (getComponents() == components))
@@ -816,6 +826,51 @@ void LLImageRaw::copyScaled( LLImageRaw* src )
 	}
 }
 
+//scale down image by not blending a pixel with its neighbors.
+BOOL LLImageRaw::scaleDownWithoutBlending( S32 new_width, S32 new_height)
+{
+	LLMemType mt1(mMemType);
+
+	S8 c = getComponents() ;
+	llassert((1 == c) || (3 == c) || (4 == c) );
+
+	S32 old_width = getWidth();
+	S32 old_height = getHeight();
+	
+	S32 new_data_size = old_width * new_height * c ;
+	llassert_always(new_data_size > 0);
+
+	F32 ratio_x = (F32)old_width / new_width ;
+	F32 ratio_y = (F32)old_height / new_height ;
+	if( ratio_x < 1.0f || ratio_y < 1.0f )
+	{
+		return TRUE;  // Nothing to do.
+	}
+	ratio_x -= 1.0f ;
+	ratio_y -= 1.0f ;
+
+	U8* new_data = new U8[new_data_size] ;
+	llassert_always(new_data != NULL) ;
+
+	U8* old_data = getData() ;
+	S32 i, j, k, s, t;
+	for(i = 0, s = 0, t = 0 ; i < new_height ; i++)
+	{
+		for(j = 0 ; j < new_width ; j++)
+		{
+			for(k = 0 ; k < c ; k++)
+			{
+				new_data[s++] = old_data[t++] ;
+			}
+			t += (S32)(ratio_x * c + 0.1f) ;
+		}
+		t += (S32)(ratio_y * old_width * c + 0.1f) ;
+	}
+
+	setDataAndSize(new_data, new_width, new_height, c) ;
+	
+	return TRUE ;
+}
 
 BOOL LLImageRaw::scale( S32 new_width, S32 new_height, BOOL scale_image_data )
 {
@@ -1223,25 +1278,28 @@ bool LLImageRaw::createFromFile(const std::string &filename, bool j2c_lowest_mip
 	ifs.read ((char*)buffer, length);
 	ifs.close();
 	
-	image->updateData();
-	
-	if (j2c_lowest_mip_only && codec == IMG_CODEC_J2C)
+	BOOL success;
+
+	success = image->updateData();
+	if (success)
 	{
-		S32 width = image->getWidth();
-		S32 height = image->getHeight();
-		S32 discard_level = 0;
-		while (width > 1 && height > 1 && discard_level < MAX_DISCARD_LEVEL)
+		if (j2c_lowest_mip_only && codec == IMG_CODEC_J2C)
 		{
-			width >>= 1;
-			height >>= 1;
-			discard_level++;
+			S32 width = image->getWidth();
+			S32 height = image->getHeight();
+			S32 discard_level = 0;
+			while (width > 1 && height > 1 && discard_level < MAX_DISCARD_LEVEL)
+			{
+				width >>= 1;
+				height >>= 1;
+				discard_level++;
+			}
+			((LLImageJ2C *)((LLImageFormatted*)image))->setDiscardLevel(discard_level);
 		}
-		((LLImageJ2C *)((LLImageFormatted*)image))->setDiscardLevel(discard_level);
+		success = image->decode(this, 100000.0f);
 	}
-	
-	BOOL success = image->decode(this, 100000.0f);
-	image = NULL; // deletes image
 
+	image = NULL; // deletes image
 	if (!success)
 	{
 		deleteData();
diff --git a/indra/llimage/llimage.h b/indra/llimage/llimage.h
index 8108553107..686f583886 100644
--- a/indra/llimage/llimage.h
+++ b/indra/llimage/llimage.h
@@ -50,7 +50,8 @@ const S32 MAX_IMAGE_AREA = MAX_IMAGE_SIZE * MAX_IMAGE_SIZE;
 const S32 MAX_IMAGE_COMPONENTS = 8;
 const S32 MAX_IMAGE_DATA_SIZE = MAX_IMAGE_AREA * MAX_IMAGE_COMPONENTS;
 
-// Note!  These CANNOT be changed without invalidating the viewer VFS files, I think?
+// Note!  These CANNOT be changed without modifying simulator code
+// *TODO: change both to 1024 when SIM texture fetching is deprecated
 const S32 FIRST_PACKET_SIZE = 600;
 const S32 MAX_IMG_PACKET_SIZE = 1000;
 
@@ -61,7 +62,6 @@ const S32 MAX_IMG_PACKET_SIZE = 1000;
 class LLImageFormatted;
 class LLImageRaw;
 class LLColor4U;
-class LLWorkerThread;
 
 typedef enum e_image_codec
 {
@@ -82,7 +82,7 @@ typedef enum e_image_codec
 class LLImage
 {
 public:
-	static void initClass(LLWorkerThread* workerthread);
+	static void initClass();
 	static void cleanupClass();
 
 	static const std::string& getLastError();
@@ -131,7 +131,7 @@ public:
 
 protected:
 	// special accessor to allow direct setting of mData and mDataSize by LLImageFormatted
-	void setDataAndSize(U8 *data, S32 size) { mData = data; mDataSize = size; };
+	void setDataAndSize(U8 *data, S32 size) { mData = data; mDataSize = size; }
 	
 public:
 	static void generateMip(const U8 *indata, U8* mipdata, int width, int height, S32 nchannels);
@@ -192,6 +192,7 @@ public:
 	void contractToPowerOfTwo(S32 max_dim = MAX_IMAGE_SIZE, BOOL scale_image = TRUE);
 	void biasedScaleToPowerOfTwo(S32 max_dim = MAX_IMAGE_SIZE);
 	BOOL scale( S32 new_width, S32 new_height, BOOL scale_image = TRUE );
+	BOOL scaleDownWithoutBlending( S32 new_width, S32 new_height) ;
 
 	// Fill the buffer with a constant color
 	void fill( const LLColor4U& color );
@@ -240,6 +241,8 @@ protected:
 
 	U8	fastFractionalMult(U8 a,U8 b);
 
+	void setDataAndSize(U8 *data, S32 width, S32 height, S8 components) ;
+
 public:
 	static S32 sGlobalRawMemory;
 	static S32 sRawImageCount;
@@ -310,7 +313,7 @@ protected:
 protected:
 	S8 mCodec;
 	S8 mDecoding;
-	S8 mDecoded;
+	S8 mDecoded;  // unused, but changing LLImage layout requires recompiling static Mac/Linux libs. 2009-01-30 JC
 	S8 mDiscardLevel;
 	
 public:
diff --git a/indra/llimage/llimagedxt.cpp b/indra/llimage/llimagedxt.cpp
index 1ce4517a0d..0aa6840ff6 100644
--- a/indra/llimage/llimagedxt.cpp
+++ b/indra/llimage/llimagedxt.cpp
@@ -264,6 +264,8 @@ void LLImageDXT::setFormat()
 // virtual
 BOOL LLImageDXT::decode(LLImageRaw* raw_image, F32 time)
 {
+	// *TODO: Test! This has been tweaked since its intial inception,
+	//  but we don't use it any more!
 	llassert_always(raw_image);
 	
 	if (mFileFormat >= FORMAT_DXT1 && mFileFormat <= FORMAT_DXR5)
@@ -274,8 +276,17 @@ BOOL LLImageDXT::decode(LLImageRaw* raw_image, F32 time)
 	
 	S32 width = getWidth(), height = getHeight();
 	S32 ncomponents = getComponents();
+	U8* data = NULL;
+	if (mDiscardLevel >= 0)
+	{
+		data = getData() + getMipOffset(mDiscardLevel);
+		calcDiscardWidthHeight(mDiscardLevel, mFileFormat, width, height);
+	}
+	else
+	{
+		data = getData() + getMipOffset(0);
+	}
 	S32 image_size = formatBytes(mFileFormat, width, height);
-	U8* data = getData() + getMipOffset(0);
 	
 	if ((!getData()) || (data + image_size > getData() + getDataSize()))
 	{
@@ -300,10 +311,8 @@ BOOL LLImageDXT::getMipData(LLPointer<LLImageRaw>& raw, S32 discard)
 		llerrs << "Request for invalid discard level" << llendl;
 	}
 	U8* data = getData() + getMipOffset(discard);
-	// I'm not sure these are the correct initial values for height and width,
-	// but previously they were being used uninitialized. JC
-	S32 width = raw->getWidth();
-	S32 height = raw->getHeight();
+	S32 width = 0;
+	S32 height = 0;
 	calcDiscardWidthHeight(discard, mFileFormat, width, height);
 	raw = new LLImageRaw(data, width, height, getComponents());
 	return TRUE;
diff --git a/indra/llimage/llimagej2c.cpp b/indra/llimage/llimagej2c.cpp
index 2352c8edd7..74f08b2d0b 100644
--- a/indra/llimage/llimagej2c.cpp
+++ b/indra/llimage/llimagej2c.cpp
@@ -283,6 +283,7 @@ BOOL LLImageJ2C::decode(LLImageRaw *raw_imagep, F32 decode_time)
 }
 
 
+// Returns TRUE to mean done, whether successful or not.
 BOOL LLImageJ2C::decodeChannels(LLImageRaw *raw_imagep, F32 decode_time, S32 first_channel, S32 max_channel_count )
 {
 	LLMemType mt1(mMemType);
@@ -295,7 +296,7 @@ BOOL LLImageJ2C::decodeChannels(LLImageRaw *raw_imagep, F32 decode_time, S32 fir
 	if (!getData() || (getDataSize() < 16))
 	{
 		setLastError("LLImageJ2C uninitialized");
-		res = FALSE;
+		res = TRUE; // done
 	}
 	else
 	{
@@ -348,7 +349,7 @@ BOOL LLImageJ2C::encode(const LLImageRaw *raw_imagep, const char* comment_text,
 //static
 S32 LLImageJ2C::calcHeaderSizeJ2C()
 {
-	return 600; //2048; // ??? hack... just needs to be >= actual header size...
+	return FIRST_PACKET_SIZE; // Hack. just needs to be >= actual header size...
 }
 
 //static
diff --git a/indra/llimage/llimagejpeg.cpp b/indra/llimage/llimagejpeg.cpp
index fa0dd3ff05..79ea79cc07 100644
--- a/indra/llimage/llimagejpeg.cpp
+++ b/indra/llimage/llimagejpeg.cpp
@@ -188,6 +188,7 @@ void LLImageJPEG::decodeTermSource (j_decompress_ptr cinfo)
 }
 
 
+// Returns true when done, whether or not decode was successful.
 BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 {
 	llassert_always(raw_image);
@@ -198,7 +199,7 @@ BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 	if (!getData() || (0 == getDataSize()))
 	{
 		setLastError("LLImageJPEG trying to decode an image with no data!");
-		return FALSE;
+		return TRUE;  // done
 	}
 	
 	S32 row_stride = 0;
@@ -226,7 +227,7 @@ BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 	if(setjmp(sSetjmpBuffer))
 	{
 		jpeg_destroy_decompress(&cinfo);
-		return FALSE;
+		return TRUE; // done
 	}
 	try
 	{
@@ -320,7 +321,7 @@ BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 	catch (int)
 	{
 		jpeg_destroy_decompress(&cinfo);
-		return FALSE;
+		return TRUE; // done
 	}
 
 	// Check to see whether any corrupt-data warnings occurred
@@ -328,7 +329,7 @@ BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
 	{
 		// TODO: extract the warning to find out what went wrong.
 		setLastError( "Unable to decode JPEG image.");
-		return FALSE;
+		return TRUE; // done
 	}
 
 	return TRUE;
diff --git a/indra/llimage/llimageworker.cpp b/indra/llimage/llimageworker.cpp
index 532e996188..86d41515e7 100644
--- a/indra/llimage/llimageworker.cpp
+++ b/indra/llimage/llimageworker.cpp
@@ -37,152 +37,138 @@
 
 //----------------------------------------------------------------------------
 
-//static
-LLWorkerThread* LLImageWorker::sWorkerThread = NULL;
-S32 LLImageWorker::sCount = 0;
+// MAIN THREAD
+LLImageDecodeThread::LLImageDecodeThread(bool threaded)
+	: LLQueuedThread("imagedecode", threaded)
+{
+	mCreationMutex = new LLMutex(getAPRPool());
+}
 
-//static
-void LLImageWorker::initImageWorker(LLWorkerThread* workerthread)
+// MAIN THREAD
+// virtual
+S32 LLImageDecodeThread::update(U32 max_time_ms)
 {
-	sWorkerThread = workerthread;
+	LLMutexLock lock(mCreationMutex);
+	for (creation_list_t::iterator iter = mCreationList.begin();
+		 iter != mCreationList.end(); ++iter)
+	{
+		creation_info& info = *iter;
+		ImageRequest* req = new ImageRequest(info.handle, info.image,
+											 info.priority, info.discard, info.needs_aux,
+											 info.responder);
+		addRequest(req);
+	}
+	mCreationList.clear();
+	S32 res = LLQueuedThread::update(max_time_ms);
+	return res;
 }
 
-//static
-void LLImageWorker::cleanupImageWorker()
+LLImageDecodeThread::handle_t LLImageDecodeThread::decodeImage(LLImageFormatted* image, 
+	U32 priority, S32 discard, BOOL needs_aux, Responder* responder)
+{
+	LLMutexLock lock(mCreationMutex);
+	handle_t handle = generateHandle();
+	mCreationList.push_back(creation_info(handle, image, priority, discard, needs_aux, responder));
+	return handle;
+}
+
+// Used by unit test only
+// Returns the size of the mutex guarded list as an indication of sanity
+S32 LLImageDecodeThread::tut_size()
+{
+	LLMutexLock lock(mCreationMutex);
+	S32 res = mCreationList.size();
+	return res;
+}
+
+LLImageDecodeThread::Responder::~Responder()
 {
 }
 
 //----------------------------------------------------------------------------
 
-LLImageWorker::LLImageWorker(LLImageFormatted* image, U32 priority,
-							 S32 discard,
-							 LLPointer<LLResponder> responder)
-	: LLWorkerClass(sWorkerThread, "Image"),
+LLImageDecodeThread::ImageRequest::ImageRequest(handle_t handle, LLImageFormatted* image, 
+												U32 priority, S32 discard, BOOL needs_aux,
+												LLImageDecodeThread::Responder* responder)
+	: LLQueuedThread::QueuedRequest(handle, priority, FLAG_AUTO_COMPLETE),
 	  mFormattedImage(image),
-	  mDecodedType(-1),
 	  mDiscardLevel(discard),
-	  mPriority(priority),
+	  mNeedsAux(needs_aux),
+	  mDecodedRaw(FALSE),
+	  mDecodedAux(FALSE),
 	  mResponder(responder)
 {
-	++sCount;
 }
 
-LLImageWorker::~LLImageWorker()
+LLImageDecodeThread::ImageRequest::~ImageRequest()
 {
-	mDecodedImage = NULL;
+	mDecodedImageRaw = NULL;
+	mDecodedImageAux = NULL;
 	mFormattedImage = NULL;
-	--sCount;
 }
 
 //----------------------------------------------------------------------------
 
-//virtual, main thread
-void LLImageWorker::startWork(S32 param)
-{
-	llassert_always(mDecodedImage.isNull());
-	mDecodedType = -1;
-}
 
-bool LLImageWorker::doWork(S32 param)
+// Returns true when done, whether or not decode was successful.
+bool LLImageDecodeThread::ImageRequest::processRequest()
 {
-	bool decoded = false;
-	if(mDecodedImage.isNull())
+	const F32 decode_time_slice = .1f;
+	bool done = true;
+	if (!mDecodedRaw && mFormattedImage.notNull())
 	{
-		if (!mFormattedImage->updateData())
-		{
-			mDecodedType = -2; // failed
-			return true;
-		}
-		if (mDiscardLevel >= 0)
+		// Decode primary channels
+		if (mDecodedImageRaw.isNull())
 		{
-			mFormattedImage->setDiscardLevel(mDiscardLevel);
-		}
-		if (!(mFormattedImage->getWidth() * mFormattedImage->getHeight() * mFormattedImage->getComponents()))
-		{
-			decoded = true; // failed
-		}
-		else
-		{
-			mDecodedImage = new LLImageRaw(); // allow possibly smaller size set during decoding
+			// parse formatted header
+			if (!mFormattedImage->updateData())
+			{
+				return true; // done (failed)
+			}
+			if (!(mFormattedImage->getWidth() * mFormattedImage->getHeight() * mFormattedImage->getComponents()))
+			{
+				return true; // done (failed)
+			}
+			if (mDiscardLevel >= 0)
+			{
+				mFormattedImage->setDiscardLevel(mDiscardLevel);
+			}
+			mDecodedImageRaw = new LLImageRaw(mFormattedImage->getWidth(),
+											  mFormattedImage->getHeight(),
+											  mFormattedImage->getComponents());
 		}
+		done = mFormattedImage->decode(mDecodedImageRaw, decode_time_slice); // 1ms
+		mDecodedRaw = done;
 	}
-	if (!decoded)
+	if (done && mNeedsAux && !mDecodedAux && mFormattedImage.notNull())
 	{
-		if (param == 0)
-		{
-			// Decode primary channels
-			decoded = mFormattedImage->decode(mDecodedImage, .1f); // 1ms
-		}
-		else
+		// Decode aux channel
+		if (!mDecodedImageAux)
 		{
-			// Decode aux channel
-			decoded = mFormattedImage->decodeChannels(mDecodedImage, .1f, param, param); // 1ms
+			mDecodedImageAux = new LLImageRaw(mFormattedImage->getWidth(),
+											  mFormattedImage->getHeight(),
+											  1);
 		}
+		done = mFormattedImage->decodeChannels(mDecodedImageAux, decode_time_slice, 4, 4); // 1ms
+		mDecodedAux = done;
 	}
-	if (decoded)
-	{
-		// Call the callback immediately; endWork doesn't get called until ckeckWork
-		if (mResponder.notNull())
-		{
-			bool success = (!wasAborted() && mDecodedImage.notNull() && mDecodedImage->getDataSize() != 0);
-			mResponder->completed(success);
-		}
-	}
-	return decoded;
-}
 
-void LLImageWorker::endWork(S32 param, bool aborted)
-{
-	if (mDecodedType != -2)
-	{
-		mDecodedType = aborted ? -2 : param;
-	}
+	return done;
 }
 
-//----------------------------------------------------------------------------
-
-
-BOOL LLImageWorker::requestDecodedAuxData(LLPointer<LLImageRaw>& raw, S32 channel, S32 discard)
+void LLImageDecodeThread::ImageRequest::finishRequest(bool completed)
 {
-	// For most codecs, only mDiscardLevel data is available.
-	//  (see LLImageDXT for exception)
-	if (discard >= 0 && discard != mFormattedImage->getDiscardLevel())
-	{
-		llerrs << "Request for invalid discard level" << llendl;
-	}
-	checkWork();
-	if (mDecodedType == -2)
+	if (mResponder.notNull())
 	{
-		return TRUE; // aborted, done
-	}
-	if (mDecodedType != channel)
-	{
-		if (!haveWork())
-		{
-			addWork(channel, mPriority);
-		}
-		return FALSE;
-	}
-	else
-	{
-		llassert_always(!haveWork());
-		llassert_always(mDecodedType == channel);
-		raw = mDecodedImage; // smart pointer acquires ownership of data
-		mDecodedImage = NULL;
-		return TRUE;
+		bool success = completed && mDecodedRaw && (!mNeedsAux || mDecodedAux);
+		mResponder->completed(success, mDecodedImageRaw, mDecodedImageAux);
 	}
+	// Will automatically be deleted
 }
 
-BOOL LLImageWorker::requestDecodedData(LLPointer<LLImageRaw>& raw, S32 discard)
+// Used by unit test only
+// Checks that a responder exists for this instance so that something can happen when completion is reached
+bool LLImageDecodeThread::ImageRequest::tut_isOK()
 {
-	if (mFormattedImage->getCodec() == IMG_CODEC_DXT)
-	{
-		// special case
-		LLImageDXT* imagedxt = (LLImageDXT*)((LLImageFormatted*)mFormattedImage);
-		return imagedxt->getMipData(raw, discard);
-	}
-	else
-	{
-		return requestDecodedAuxData(raw, 0, discard);
-	}
+	return mResponder.notNull();
 }
diff --git a/indra/llimage/llimageworker.h b/indra/llimage/llimageworker.h
index 0d66695d6e..6a5b86a277 100644
--- a/indra/llimage/llimageworker.h
+++ b/indra/llimage/llimageworker.h
@@ -37,49 +37,72 @@
 #include "llpointer.h"
 #include "llworkerthread.h"
 
-class LLImageWorker : public LLWorkerClass
+class LLImageDecodeThread : public LLQueuedThread
 {
 public:
-	static void initImageWorker(LLWorkerThread* workerthread);
-	static void cleanupImageWorker();
-	
-public:
-	static LLWorkerThread* getWorkerThread() { return sWorkerThread; }
-
-	// LLWorkerThread
-public:
-	LLImageWorker(LLImageFormatted* image, U32 priority, S32 discard,
-				  LLPointer<LLResponder> responder);
-	~LLImageWorker();
-
-	// called from WORKER THREAD, returns TRUE if done
-	/*virtual*/ bool doWork(S32 param);
-	
-	BOOL requestDecodedData(LLPointer<LLImageRaw>& raw, S32 discard = -1);
-	BOOL requestDecodedAuxData(LLPointer<LLImageRaw>& raw, S32 channel, S32 discard = -1);
-	void releaseDecodedData();
-	void cancelDecode();
+	class Responder : public LLThreadSafeRefCount
+	{
+	protected:
+		virtual ~Responder();
+	public:
+		virtual void completed(bool success, LLImageRaw* raw, LLImageRaw* aux) = 0;
+	};
 
-private:
-	// called from MAIN THREAD
-	/*virtual*/ void startWork(S32 param); // called from addWork()
-	/*virtual*/ void endWork(S32 param, bool aborted); // called from doWork()
+	class ImageRequest : public LLQueuedThread::QueuedRequest
+	{
+	protected:
+		virtual ~ImageRequest(); // use deleteRequest()
+		
+	public:
+		ImageRequest(handle_t handle, LLImageFormatted* image,
+					 U32 priority, S32 discard, BOOL needs_aux,
+					 LLImageDecodeThread::Responder* responder);
 
-protected:
-	LLPointer<LLImageFormatted> mFormattedImage;
-	LLPointer<LLImageRaw> mDecodedImage;
-	S32 mDecodedType;
-	S32 mDiscardLevel;
+		/*virtual*/ bool processRequest();
+		/*virtual*/ void finishRequest(bool completed);
 
-private:
-	U32 mPriority;
-	LLPointer<LLResponder> mResponder;
+		// Used by unit tests to check the consitency of the request instance
+		bool tut_isOK();
+		
+	private:
+		// input
+		LLPointer<LLImageFormatted> mFormattedImage;
+		S32 mDiscardLevel;
+		BOOL mNeedsAux;
+		// output
+		LLPointer<LLImageRaw> mDecodedImageRaw;
+		LLPointer<LLImageRaw> mDecodedImageAux;
+		BOOL mDecodedRaw;
+		BOOL mDecodedAux;
+		LLPointer<LLImageDecodeThread::Responder> mResponder;
+	};
 	
-protected:
-	static LLWorkerThread* sWorkerThread;
-
 public:
-	static S32 sCount;
+	LLImageDecodeThread(bool threaded = true);
+	handle_t decodeImage(LLImageFormatted* image,
+						 U32 priority, S32 discard, BOOL needs_aux,
+						 Responder* responder);
+	S32 update(U32 max_time_ms);
+
+	// Used by unit tests to check the consistency of the thread instance
+	S32 tut_size();
+	
+private:
+	struct creation_info
+	{
+		handle_t handle;
+		LLPointer<LLImageFormatted> image;
+		U32 priority;
+		S32 discard;
+		BOOL needs_aux;
+		LLPointer<Responder> responder;
+		creation_info(handle_t h, LLImageFormatted* i, U32 p, S32 d, BOOL aux, Responder* r)
+			: handle(h), image(i), priority(p), discard(d), needs_aux(aux), responder(r)
+		{}
+	};
+	typedef std::list<creation_info> creation_list_t;
+	creation_list_t mCreationList;
+	LLMutex* mCreationMutex;
 };
 
 #endif
diff --git a/indra/llimage/tests/llimageworker_test.cpp b/indra/llimage/tests/llimageworker_test.cpp
new file mode 100644
index 0000000000..cc44696a45
--- /dev/null
+++ b/indra/llimage/tests/llimageworker_test.cpp
@@ -0,0 +1,260 @@
+/** 
+ * @file llimageworker_test.cpp
+ * @author Merov Linden
+ * @date 2009-04-28
+ *
+ * $LicenseInfo:firstyear=2006&license=viewergpl$
+ * 
+ * Copyright (c) 2006-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header: almost always required for newview cpp files
+#include <list>
+#include <map>
+#include <algorithm>
+// Class to test
+#include "../llimageworker.h"
+// For timer class
+#include "../llcommon/lltimer.h"
+// Tut header
+#include "../test/lltut.h"
+
+// -------------------------------------------------------------------------------------------
+// Stubbing: Declarations required to link and run the class being tested
+// Notes: 
+// * Add here stubbed implementation of the few classes and methods used in the class to be tested
+// * Add as little as possible (let the link errors guide you)
+// * Do not make any assumption as to how those classes or methods work (i.e. don't copy/paste code)
+// * A simulator for a class can be implemented here. Please comment and document thoroughly.
+
+LLImageBase::LLImageBase() {}
+LLImageBase::~LLImageBase() {}
+void LLImageBase::dump() { }
+void LLImageBase::sanityCheck() { }
+void LLImageBase::deleteData() { }
+U8* LLImageBase::allocateData(S32 size) { return NULL; }
+U8* LLImageBase::reallocateData(S32 size) { return NULL; }
+
+LLImageRaw::LLImageRaw(U16 width, U16 height, S8 components) { }
+LLImageRaw::~LLImageRaw() { }
+void LLImageRaw::deleteData() { }
+U8* LLImageRaw::allocateData(S32 size) { return NULL; }
+U8* LLImageRaw::reallocateData(S32 size) { return NULL; }
+
+// End Stubbing
+// -------------------------------------------------------------------------------------------
+
+// -------------------------------------------------------------------------------------------
+// TUT
+// -------------------------------------------------------------------------------------------
+
+namespace tut
+{
+	// Test wrapper declarations
+
+	// Note: We derive the responder class for 2 reasons:
+	// 1. It's a pure virtual class and we can't compile without completed() being implemented
+	// 2. We actually need a responder to test that the thread work test completed
+	// We implement this making no assumption on what's done in the thread or worker
+	// though, just that the responder's completed() method is called in the end.
+	// Note on responders: responders are ref counted and *will* be deleted by the request they are 
+	// attached to when the queued request is deleted. The recommended way of using them is to 
+	// create them when creating a request, put a callback method in completed() and not rely on 
+	// anything to survive in the responder object once completed() has been called. Let the request
+	// do the deletion and clean up itself.
+	class responder_test : public LLImageDecodeThread::Responder
+	{
+		public:
+			responder_test(bool* res)
+			{ 
+				done = res;
+				*done = false;
+			}
+			virtual void completed(bool success, LLImageRaw* raw, LLImageRaw* aux)
+			{
+				*done = true;
+			}
+		private:
+			// This is what can be thought of as the minimal implementation of a responder
+			// Done will be switched to true when completed() is called and can be tested
+			// outside the responder. A better way of doing this is to store a callback here.
+			bool* done;
+	};
+
+	// Test wrapper declaration : decode thread
+	struct imagedecodethread_test
+	{
+		// Instance to be tested
+		LLImageDecodeThread* mThread;
+
+		// Constructor and destructor of the test wrapper
+		imagedecodethread_test()
+		{
+			mThread = NULL;
+		}
+		~imagedecodethread_test()
+		{
+			delete mThread;
+		}
+	};
+
+	// Test wrapper declaration : image worker
+	// Note: this class is not meant to be instantiated outside an LLImageDecodeThread instance
+	// but it's not a bad idea to get its public API a good shake as part of a thorough unit test set.
+	// Some gotcha with the destructor though (see below).
+	struct imagerequest_test
+	{
+		// Instance to be tested
+		LLImageDecodeThread::ImageRequest* mRequest;
+		bool done;
+
+		// Constructor and destructor of the test wrapper
+		imagerequest_test()
+		{
+			done = false;
+			mRequest = new LLImageDecodeThread::ImageRequest(0, 0,
+											 LLQueuedThread::PRIORITY_NORMAL, 0, FALSE,
+											 new responder_test(&done));
+		}
+		~imagerequest_test()
+		{
+			// We should delete the object *but*, because its destructor is protected, that cannot be
+			// done from outside an LLImageDecodeThread instance... So we leak memory here... It's fine...
+			//delete mRequest;
+		}
+	};
+
+	// Tut templating thingamagic: test group, object and test instance
+	typedef test_group<imagedecodethread_test> imagedecodethread_t;
+	typedef imagedecodethread_t::object imagedecodethread_object_t;
+	tut::imagedecodethread_t tut_imagedecodethread("imagedecodethread");
+
+	typedef test_group<imagerequest_test> imagerequest_t;
+	typedef imagerequest_t::object imagerequest_object_t;
+	tut::imagerequest_t tut_imagerequest("imagerequest");
+
+	// ---------------------------------------------------------------------------------------
+	// Test functions
+	// Notes:
+	// * Test as many as you possibly can without requiring a full blown simulation of everything
+	// * The tests are executed in sequence so the test instance state may change between calls
+	// * Remember that you cannot test private methods with tut
+	// ---------------------------------------------------------------------------------------
+
+	// ---------------------------------------------------------------------------------------
+	// Test the LLImageDecodeThread interface
+	// ---------------------------------------------------------------------------------------
+	//
+	// Note on Unit Testing Queued Thread Classes
+	//
+	// Since methods on such a class are called on a separate loop and that we can't insert tut
+	// ensure() calls in there, we exercise the class with 2 sets of tests:
+	// - 1: Test as a single threaded instance: We declare the class but ask for no thread
+	//   to be spawned (easy with LLThreads since there's a boolean argument on the constructor
+	//   just for that). We can then unit test each public method like we do on a normal class.
+	// - 2: Test as a threaded instance: We let the thread launch and check that its external 
+	//   behavior is as expected (i.e. it runs, can accept a work order and processes
+	//   it). Typically though there's no guarantee that this exercises all the methods of the
+	//   class which is why we also need the previous "non threaded" set of unit tests for
+	//   complete coverage.
+	//
+	// ---------------------------------------------------------------------------------------
+
+	template<> template<>
+	void imagedecodethread_object_t::test<1>()
+	{
+		// Test a *non threaded* instance of the class
+		mThread = new LLImageDecodeThread(false);
+		ensure("LLImageDecodeThread: non threaded constructor failed", mThread != NULL);
+		// Test that we start with an empty list right at creation
+		ensure("LLImageDecodeThread: non threaded init state incorrect", mThread->tut_size() == 0);
+		// Insert something in the queue
+		bool done = false;
+		LLImageDecodeThread::handle_t decodeHandle = mThread->decodeImage(NULL, LLQueuedThread::PRIORITY_NORMAL, 0, FALSE, new responder_test(&done));
+		// Verifies we got a valid handle
+		ensure("LLImageDecodeThread: non threaded decodeImage(), returned handle is null", decodeHandle != 0);
+		// Verifies that we do now have something in the queued list
+		ensure("LLImageDecodeThread: non threaded decodeImage() insertion in threaded list failed", mThread->tut_size() == 1);
+		// Trigger queue handling "manually" (on a threaded instance, this is done on the thread loop)
+		S32 res = mThread->update(0);
+		// Verifies that we successfully handled the list
+		ensure("LLImageDecodeThread: non threaded update() list handling test failed", res == 0);
+		// Verifies that the list is now empty
+		ensure("LLImageDecodeThread: non threaded update() list emptying test failed", mThread->tut_size() == 0);
+	}
+
+	template<> template<>
+	void imagedecodethread_object_t::test<2>()
+	{
+		// Test a *threaded* instance of the class
+		mThread = new LLImageDecodeThread(true);
+		ensure("LLImageDecodeThread: threaded constructor failed", mThread != NULL);
+		// Test that we start with an empty list right at creation
+		ensure("LLImageDecodeThread: threaded init state incorrect", mThread->tut_size() == 0);
+		// Insert something in the queue
+		bool done = false;
+		LLImageDecodeThread::handle_t decodeHandle = mThread->decodeImage(NULL, LLQueuedThread::PRIORITY_NORMAL, 0, FALSE, new responder_test(&done));
+		// Verifies we get back a valid handle
+		ensure("LLImageDecodeThread:  threaded decodeImage(), returned handle is null", decodeHandle != 0);
+		// Wait a little so to simulate the main thread doing something on its main loop...
+		ms_sleep(500);		// 500 milliseconds
+		// Verifies that the responder has *not* been called yet in the meantime
+		ensure("LLImageDecodeThread: responder creation failed", done == false);
+		// Ask the thread to update: that means tells the queue to check itself and creates work requests
+		mThread->update(1);
+		// Wait till the thread has time to handle the work order (though it doesn't do much per work order...)
+		const U32 INCREMENT_TIME = 500;				// 500 milliseconds
+		const U32 MAX_TIME = 20 * INCREMENT_TIME;	// Do the loop 20 times max, i.e. wait 10 seconds but no more
+		U32 total_time = 0;
+		while ((done == false) && (total_time < MAX_TIME))
+		{
+			ms_sleep(INCREMENT_TIME);
+			total_time += INCREMENT_TIME;
+		}
+		// Verifies that the responder has now been called
+		ensure("LLImageDecodeThread: threaded work unit not processed", done == true);
+	}
+
+	// ---------------------------------------------------------------------------------------
+	// Test the LLImageDecodeThread::ImageRequest interface
+	// ---------------------------------------------------------------------------------------
+	
+	template<> template<>
+	void imagerequest_object_t::test<1>()
+	{
+		// Test that we start with a correct request at creation
+		ensure("LLImageDecodeThread::ImageRequest::ImageRequest() constructor test failed", mRequest->tut_isOK());
+		bool res = mRequest->processRequest();
+		// Verifies that we processed the request successfully
+		ensure("LLImageDecodeThread::ImageRequest::processRequest() processing request test failed", res == true);
+		// Check that we can call the finishing call safely
+		try {
+			mRequest->finishRequest(false);
+		} catch (...) {
+			fail("LLImageDecodeThread::ImageRequest::finishRequest() test failed");
+		}
+	}
+}