merge QAR-1579: texture-cleanup-1.

9 files changed, 206 insertions, 172 deletions

diff --git a/indra/llrender/CMakeLists.txt b/indra/llrender/CMakeLists.txt
index 0bb835970f..0e0fc6ce6c 100644
--- a/indra/llrender/CMakeLists.txt
+++ b/indra/llrender/CMakeLists.txt
@@ -36,6 +36,7 @@ set(llrender_SOURCE_FILES
     llpostprocess.cpp
     llrendersphere.cpp
     llshadermgr.cpp
+    lltexture.cpp
     llvertexbuffer.cpp
     )
     
@@ -58,6 +59,7 @@ set(llrender_HEADER_FILES
     llrender.h
     llrendersphere.h
     llshadermgr.h
+    lltexture.h
     llvertexbuffer.h
     )
 
diff --git a/indra/llrender/llfontgl.cpp b/indra/llrender/llfontgl.cpp
index 048bfe8e0d..0b57d86c78 100644
--- a/indra/llrender/llfontgl.cpp
+++ b/indra/llrender/llfontgl.cpp
@@ -43,6 +43,7 @@
 #include "llrender.h"
 #include "llstl.h"
 #include "v4color.h"
+#include "lltexture.h"
 
 // Third party library includes
 #include <boost/tokenizer.hpp>
@@ -1114,15 +1115,15 @@ void LLFontGL::clearEmbeddedChars()
 	mEmbeddedChars.clear();
 }
 
-void LLFontGL::addEmbeddedChar( llwchar wc, LLImageGL* image, const std::string& label ) const
+void LLFontGL::addEmbeddedChar( llwchar wc, LLTexture* image, const std::string& label ) const
 {
 	LLWString wlabel = utf8str_to_wstring(label);
 	addEmbeddedChar(wc, image, wlabel);
 }
 
-void LLFontGL::addEmbeddedChar( llwchar wc, LLImageGL* image, const LLWString& wlabel ) const
+void LLFontGL::addEmbeddedChar( llwchar wc, LLTexture* image, const LLWString& wlabel ) const
 {
-	embedded_data_t* ext_data = new embedded_data_t(image, wlabel);
+	embedded_data_t* ext_data = new embedded_data_t(image->getGLTexture(), wlabel);
 	mEmbeddedChars[wc] = ext_data;
 }
 
diff --git a/indra/llrender/llfontgl.h b/indra/llrender/llfontgl.h
index 77cd12250c..2298db0ef3 100644
--- a/indra/llrender/llfontgl.h
+++ b/indra/llrender/llfontgl.h
@@ -206,8 +206,8 @@ public:
 
 	LLImageGL *getImageGL() const;
 
-	void	   addEmbeddedChar( llwchar wc, LLImageGL* image, const std::string& label) const;
-	void	   addEmbeddedChar( llwchar wc, LLImageGL* image, const LLWString& label) const;
+	void	   addEmbeddedChar( llwchar wc, LLTexture* image, const std::string& label) const;
+	void	   addEmbeddedChar( llwchar wc, LLTexture* image, const LLWString& label) const;
 	void	   removeEmbeddedChar( llwchar wc ) const;
 
 	static std::string nameFromFont(const LLFontGL* fontp);
diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp
index e1231eeeb4..c4d91209e6 100644
--- a/indra/llrender/llimagegl.cpp
+++ b/indra/llrender/llimagegl.cpp
@@ -46,7 +46,6 @@
 
 
 //----------------------------------------------------------------------------
-
 const F32 MIN_TEXTURE_LIFETIME = 10.f;
 
 //statics
@@ -61,7 +60,7 @@ S32 LLImageGL::sCount					= 0;
 
 BOOL LLImageGL::sGlobalUseAnisotropic	= FALSE;
 F32 LLImageGL::sLastFrameTime			= 0.f;
-
+LLImageGL* LLImageGL::sDefaultGLTexture = NULL ;
 std::set<LLImageGL*> LLImageGL::sImageList;
 
 //**************************************************************************************
@@ -263,28 +262,6 @@ void LLImageGL::restoreGL()
 }
 
 //----------------------------------------------------------------------------
-
-//static 
-BOOL LLImageGL::create(LLPointer<LLImageGL>& dest, BOOL usemipmaps)
-{
-	dest = new LLImageGL(usemipmaps);
-	return TRUE;
-}
-
-BOOL LLImageGL::create(LLPointer<LLImageGL>& dest, U32 width, U32 height, U8 components, BOOL usemipmaps)
-{
-	dest = new LLImageGL(width, height, components, usemipmaps);
-	return TRUE;
-}
-
-BOOL LLImageGL::create(LLPointer<LLImageGL>& dest, const LLImageRaw* imageraw, BOOL usemipmaps)
-{
-	dest = new LLImageGL(imageraw, usemipmaps);
-	return TRUE;
-}
-
-//----------------------------------------------------------------------------
-
 LLImageGL::LLImageGL(BOOL usemipmaps)
 	: mSaveData(0)
 {
@@ -331,7 +308,6 @@ void LLImageGL::init(BOOL usemipmaps)
 #endif
 
 	mPickMask		  = NULL;
-	mTextureState       = NO_DELETE ;
 	mTextureMemory    = 0;
 	mLastBindTime     = 0.f;
 
@@ -351,8 +327,7 @@ void LLImageGL::init(BOOL usemipmaps)
 	mComponents			= 0;
 	
 	mMaxDiscardLevel = MAX_DISCARD_LEVEL;
-	mCurrentDiscardLevel = -1;
-	mDontDiscard = FALSE;
+	mCurrentDiscardLevel = -1;	
 	
 	mFormatInternal = -1;
 	mFormatPrimary = (LLGLenum) 0;
@@ -462,7 +437,7 @@ void LLImageGL::dump()
 
 //----------------------------------------------------------------------------
 
-void LLImageGL::updateBindStats(void) const
+BOOL LLImageGL::updateBindStats(S32 tex_mem) const
 {	
 	if (mTexName != 0)
 	{
@@ -474,38 +449,18 @@ void LLImageGL::updateBindStats(void) const
 		{
 			// we haven't accounted for this texture yet this frame
 			sUniqueCount++;
-			updateBoundTexMem(mTextureMemory);
+			updateBoundTexMem(tex_mem);
 			mLastBindTime = sLastFrameTime;
 
-			if(LLFastTimer::sMetricLog)
-			{
-				updateTestStats() ;
-			}
+			return TRUE ;
 		}
 	}
+	return FALSE ;
 }
 
-//virtual 
-void LLImageGL::updateTestStats(void) const
-{
-}
-
-//virtual
-bool LLImageGL::bindError(const S32 stage) const
-{
-	return false;
-}
-
-//virtual
-bool LLImageGL::bindDefaultImage(const S32 stage) const
-{
-	return false;
-}
-
-//virtual
-void LLImageGL::forceImmediateUpdate()
+F32 LLImageGL::getTimePassedSinceLastBound()
 {
-	return ;
+	return sLastFrameTime - mLastBindTime ;
 }
 
 void LLImageGL::setExplicitFormat( LLGLint internal_format, LLGLenum primary_format, LLGLenum type_format, BOOL swap_bytes )
@@ -1052,7 +1007,6 @@ BOOL LLImageGL::createGLTexture(S32 discard_level, const U8* data_in, BOOL data_
 
 	mTextureMemory = getMipBytes(discard_level);
 	sGlobalTextureMemoryInBytes += mTextureMemory;
-	setActive() ;
 
 	// mark this as bound at this point, so we don't throw it out immediately
 	mLastBindTime = sLastFrameTime;
@@ -1068,12 +1022,7 @@ BOOL LLImageGL::setDiscardLevel(S32 discard_level)
 
 	discard_level = llclamp(discard_level, 0, (S32)mMaxDiscardLevel);	
 
-	if (mDontDiscard)
-	{
-		// don't discard!
-		return FALSE;
-	}
-	else if (discard_level == mCurrentDiscardLevel)
+	if (discard_level == mCurrentDiscardLevel)
 	{
 		// nothing to do
 		return FALSE;
@@ -1255,8 +1204,7 @@ void LLImageGL::destroyGLTexture()
 		sGlobalTextureMemoryInBytes -= mTextureMemory;
 		mTextureMemory = 0;
 
-		LLImageGL::deleteTextures(1, &mTexName);
-		mTextureState = DELETED ;		
+		LLImageGL::deleteTextures(1, &mTexName);			
 		mTexName = 0;
 		mCurrentDiscardLevel = -1 ; //invalidate mCurrentDiscardLevel.
 		mGLTextureCreated = FALSE ;
@@ -1440,57 +1388,6 @@ void LLImageGL::analyzeAlpha(const void* data_in, S32 w, S32 h)
 	}
 }
 
-BOOL LLImageGL::isDeleted()  
-{ 
-	return mTextureState == DELETED ; 
-}
-
-BOOL LLImageGL::isInactive()  
-{ 
-	return mTextureState == INACTIVE ; 
-}
-
-BOOL LLImageGL::isDeletionCandidate()  
-{ 
-	return mTextureState == DELETION_CANDIDATE ; 
-}
-
-void LLImageGL::setDeletionCandidate()  
-{ 
-	if(mTexName && (mTextureState == INACTIVE))
-	{
-		mTextureState = DELETION_CANDIDATE ;		
-	}
-}
-
-void LLImageGL::forceActive()
-{
-	mTextureState = ACTIVE ; 
-}
-
-void LLImageGL::setActive() 
-{ 
-	if(mTextureState != NO_DELETE)
-	{
-		mTextureState = ACTIVE ; 
-	}
-}
-
-//set the texture inactive
-void LLImageGL::setInactive()
-{
-	if(mTexName && (mTextureState == ACTIVE) && !getBoundRecently())
-	{
-		mTextureState = INACTIVE ; 
-	}
-}
-
-//set the texture to stay in memory
-void LLImageGL::setNoDelete() 
-{ 
-	mTextureState = NO_DELETE ;
-}
-
 //----------------------------------------------------------------------------
 void LLImageGL::updatePickMask(S32 width, S32 height, const U8* data_in)
 {
diff --git a/indra/llrender/llimagegl.h b/indra/llrender/llimagegl.h
index 1775ae7de9..84c0f8746e 100644
--- a/indra/llrender/llimagegl.h
+++ b/indra/llrender/llimagegl.h
@@ -57,8 +57,8 @@ public:
 	static S32 dataFormatBytes(S32 dataformat, S32 width, S32 height);
 	static S32 dataFormatComponents(S32 dataformat);
 
-	void updateBindStats(void) const;
-	virtual void updateTestStats(void) const;
+	BOOL updateBindStats(S32 tex_mem) const ;
+	F32 getTimePassedSinceLastBound();
 
 	// needs to be called every frame
 	static void updateStats(F32 current_time);
@@ -72,12 +72,6 @@ public:
 
 	static bool checkSize(S32 width, S32 height);
 	
-	// Not currently necessary for LLImageGL, but required in some derived classes,
-	// so include for compatability
-	static BOOL create(LLPointer<LLImageGL>& dest, BOOL usemipmaps = TRUE);
-	static BOOL create(LLPointer<LLImageGL>& dest, U32 width, U32 height, U8 components, BOOL usemipmaps = TRUE);
-	static BOOL create(LLPointer<LLImageGL>& dest, const LLImageRaw* imageraw, BOOL usemipmaps = TRUE);
-	
 public:
 	LLImageGL(BOOL usemipmaps = TRUE);
 	LLImageGL(U32 width, U32 height, U8 components, BOOL usemipmaps = TRUE);
@@ -90,11 +84,9 @@ protected:
 
 public:
 	virtual void dump();	// debugging info to llinfos
-	virtual bool bindError(const S32 stage = 0) const;
-	virtual bool bindDefaultImage(const S32 stage = 0) const;
-	virtual void forceImmediateUpdate() ;
-
+	
 	void setSize(S32 width, S32 height, S32 ncomponents);
+	void setComponents(S32 ncomponents) { mComponents = (S8)ncomponents ;}
 
 	// These 3 functions currently wrap glGenTextures(), glDeleteTextures(), and glTexImage2D() 
 	// for tracking purposes and will be deprecated in the future
@@ -116,7 +108,6 @@ public:
 	void destroyGLTexture();
 
 	void setExplicitFormat(LLGLint internal_format, LLGLenum primary_format, LLGLenum type_format = 0, BOOL swap_bytes = FALSE);
-	void dontDiscard() { mDontDiscard = 1; mTextureState = NO_DELETE; }
 
 	S32	 getDiscardLevel() const		{ return mCurrentDiscardLevel; }
 	S32	 getMaxDiscardLevel() const		{ return mMaxDiscardLevel; }
@@ -145,9 +136,7 @@ public:
 	void setGLTextureCreated (bool initialized) { mGLTextureCreated = initialized; }
 
 	BOOL getUseMipMaps() const { return mUseMipMaps; }
-	void setUseMipMaps(BOOL usemips) { mUseMipMaps = usemips; }
-	BOOL getUseDiscard() const { return mUseMipMaps && !mDontDiscard; }
-	BOOL getDontDiscard() const { return mDontDiscard; }
+	void setUseMipMaps(BOOL usemips) { mUseMipMaps = usemips; }	
 
 	BOOL isValidForSculpt(S32 discard_level, S32 image_width, S32 image_height, S32 ncomponents) ;
 
@@ -168,16 +157,6 @@ public:
 	void setFilteringOption(LLTexUnit::eTextureFilterOptions option);
 	LLTexUnit::eTextureFilterOptions getFilteringOption(void) const { return mFilterOption; }
 
-	BOOL isDeleted() ;
-	BOOL isInactive() ;
-	BOOL isDeletionCandidate();
-	void setDeletionCandidate() ;
-	void setInactive() ;
-	void setActive() ;
-	void forceActive() ;
-	void setNoDelete() ;
-
-protected:
 	void init(BOOL usemipmaps);
 	virtual void cleanup(); // Clean up the LLImageGL so it can be reinitialized.  Be careful when using this in derived class destructors
 
@@ -210,28 +189,15 @@ protected:
 	
 	S8 mComponents;
 	S8 mMaxDiscardLevel;	
-	S8 mDontDiscard;			// Keep full res version of this image (for UI, etc)
-
+	
 	bool	mTexOptionsDirty;
 	LLTexUnit::eTextureAddressMode		mAddressMode;	// Defaults to TAM_WRAP
 	LLTexUnit::eTextureFilterOptions	mFilterOption;	// Defaults to TFO_TRILINEAR
-
 	
 	LLGLint  mFormatInternal; // = GL internalformat
 	LLGLenum mFormatPrimary;  // = GL format (pixel data format)
 	LLGLenum mFormatType;
 	BOOL	 mFormatSwapBytes;// if true, use glPixelStorei(GL_UNPACK_SWAP_BYTES, 1)
-
-protected:
-	typedef enum 
-	{
-		DELETED = 0,         //removed from memory
-		DELETION_CANDIDATE,  //ready to be removed from memory
-		INACTIVE,            //not be used for the last certain period (i.e., 30 seconds).
-		ACTIVE,              //just being used, can become inactive if not being used for a certain time (10 seconds).
-		NO_DELETE = 99       //stay in memory, can not be removed.
-	} LLGLTexureState;
-	LLGLTexureState  mTextureState ;
 	
 	// STATICS
 public:	
@@ -249,6 +215,7 @@ public:
 	static U32 sBindCount;					// Tracks number of texture binds for current frame
 	static U32 sUniqueCount;				// Tracks number of unique texture binds for current frame
 	static BOOL sGlobalUseAnisotropic;
+	static LLImageGL* sDefaultGLTexture ;
 
 #if DEBUG_MISS
 	BOOL mMissed; // Missed on last bind?
diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index d3a230b37b..d577daf3f4 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -38,6 +38,7 @@
 #include "llcubemap.h"
 #include "llimagegl.h"
 #include "llrendertarget.h"
+#include "lltexture.h"
 
 LLRender gGL;
 
@@ -177,20 +178,21 @@ void LLTexUnit::disable(void)
 	}
 }
 
-bool LLTexUnit::bind(LLImageGL* texture, bool forceBind)
+bool LLTexUnit::bind(LLTexture* texture, bool forceBind)
 {
 	stop_glerror();
 	if (mIndex < 0) return false;
 
 	gGL.flush();
 
-	if (texture == NULL)
+	LLImageGL* gl_tex = NULL ;
+	if (texture == NULL || !(gl_tex = texture->getGLTexture()))
 	{
 		llwarns << "NULL LLTexUnit::bind texture" << llendl;
 		return false;
 	}
 
-	if (!texture->getTexName()) //if texture does not exist
+	if (!gl_tex->getTexName()) //if texture does not exist
 	{
 		//if deleted, will re-generate it immediately
 		texture->forceImmediateUpdate() ;
@@ -198,14 +200,57 @@ bool LLTexUnit::bind(LLImageGL* texture, bool forceBind)
 		return texture->bindDefaultImage(mIndex);
 	}
 
+	if ((mCurrTexture != gl_tex->getTexName()) || forceBind)
+	{
+		activate();
+		enable(gl_tex->getTarget());
+		mCurrTexture = gl_tex->getTexName();
+		glBindTexture(sGLTextureType[gl_tex->getTarget()], mCurrTexture);
+		if(gl_tex->updateBindStats(gl_tex->mTextureMemory))
+		{
+			texture->setActive() ;
+			texture->updateBindStatsForTester() ;
+		}
+		mHasMipMaps = gl_tex->mHasMipMaps;
+		if (gl_tex->mTexOptionsDirty)
+		{
+			gl_tex->mTexOptionsDirty = false;
+			setTextureAddressMode(gl_tex->mAddressMode);
+			setTextureFilteringOption(gl_tex->mFilterOption);
+		}
+	}
+	return true;
+}
+
+bool LLTexUnit::bind(LLImageGL* texture, bool forceBind)
+{
+	stop_glerror();
+	if (mIndex < 0) return false;
+
+	if(!texture)
+	{
+		llwarns << "NULL LLTexUnit::bind texture" << llendl;
+		return false;
+	}
+
+	if(!texture->getTexName())
+	{
+		if(LLImageGL::sDefaultGLTexture && LLImageGL::sDefaultGLTexture->getTexName())
+		{
+			return bind(LLImageGL::sDefaultGLTexture) ;
+		}
+		return false ;
+	}
+
+	gGL.flush();
+
 	if ((mCurrTexture != texture->getTexName()) || forceBind)
 	{
 		activate();
 		enable(texture->getTarget());
 		mCurrTexture = texture->getTexName();
 		glBindTexture(sGLTextureType[texture->getTarget()], mCurrTexture);
-		texture->updateBindStats();
-		texture->setActive() ;
+		texture->updateBindStats(texture->mTextureMemory);		
 		mHasMipMaps = texture->mHasMipMaps;
 		if (texture->mTexOptionsDirty)
 		{
@@ -238,7 +283,7 @@ bool LLTexUnit::bind(LLCubeMap* cubeMap)
 			mCurrTexture = cubeMap->mImages[0]->getTexName();
 			glBindTexture(GL_TEXTURE_CUBE_MAP_ARB, mCurrTexture);
 			mHasMipMaps = cubeMap->mImages[0]->mHasMipMaps;
-			cubeMap->mImages[0]->updateBindStats();
+			cubeMap->mImages[0]->updateBindStats(cubeMap->mImages[0]->mTextureMemory);
 			if (cubeMap->mImages[0]->mTexOptionsDirty)
 			{
 				cubeMap->mImages[0]->mTexOptionsDirty = false;
@@ -279,15 +324,21 @@ bool LLTexUnit::bind(LLRenderTarget* renderTarget, bool bindDepth)
 
 bool LLTexUnit::bindManual(eTextureType type, U32 texture, bool hasMips)
 {
-	if (mIndex < 0 || mCurrTexture == texture) return false;
+	if (mIndex < 0)  
+	{
+		return false;
+	}
 
-	gGL.flush();
-	
-	activate();
-	enable(type);
-	mCurrTexture = texture;
-	glBindTexture(sGLTextureType[type], texture);
-	mHasMipMaps = hasMips;
+	if(mCurrTexture != texture)
+	{
+		gGL.flush();
+		
+		activate();
+		enable(type);
+		mCurrTexture = texture;
+		glBindTexture(sGLTextureType[type], texture);
+		mHasMipMaps = hasMips;
+	}
 	return true;
 }
 
diff --git a/indra/llrender/llrender.h b/indra/llrender/llrender.h
index 31083d8286..74f87f6d40 100644
--- a/indra/llrender/llrender.h
+++ b/indra/llrender/llrender.h
@@ -51,6 +51,7 @@ class LLVertexBuffer;
 class LLCubeMap;
 class LLImageGL;
 class LLRenderTarget;
+class LLTexture ;
 
 class LLTexUnit
 {
@@ -149,6 +150,7 @@ public:
 	// Binds the LLImageGL to this texture unit 
 	// (automatically enables the unit for the LLImageGL's texture type)
 	bool bind(LLImageGL* texture, bool forceBind = false);
+	bool bind(LLTexture* texture, bool forceBind = false);
 
 	// Binds a cubemap to this texture unit 
 	// (automatically enables the texture unit for cubemaps)
diff --git a/indra/llrender/lltexture.cpp b/indra/llrender/lltexture.cpp
new file mode 100644
index 0000000000..156ffb953c
--- /dev/null
+++ b/indra/llrender/lltexture.cpp
@@ -0,0 +1,37 @@
+/** 
+ * @file lltexture.cpp
+ *
+ * $LicenseInfo:firstyear=2000&license=viewergpl$
+ * 
+ * Copyright (c) 2000-2009, 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.
+ * $/LicenseInfo$
+ */
+#include "linden_common.h"
+#include "lltexture.h"
+
+//virtual 
+LLTexture::~LLTexture()
+{
+}
diff --git a/indra/llrender/lltexture.h b/indra/llrender/lltexture.h
new file mode 100644
index 0000000000..c18917b663
--- /dev/null
+++ b/indra/llrender/lltexture.h
@@ -0,0 +1,77 @@
+/** 
+ * @file lltexture.h
+ * @brief LLTexture definition
+ *
+ *	This class acts as a wrapper for OpenGL calls.
+ *	The goal of this class is to minimize the number of api calls due to legacy rendering
+ *	code, to define an interface for a multiple rendering API abstraction of the UI
+ *	rendering, and to abstract out direct rendering calls in a way that is cleaner and easier to maintain.
+ *
+ * $LicenseInfo:firstyear=2001&license=viewergpl$
+ * 
+ * Copyright (c) 2001-2009, 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.
+ * $/LicenseInfo$
+ */
+
+#ifndef LL_TEXTURE_H
+#define LL_TEXTURE_H
+
+#include "llrefcount.h"
+class LLImageGL ;
+class LLTexUnit ;
+class LLFontGL ;
+
+//
+//this is an abstract class as the parent for the class LLViewerTexture
+//through the following virtual functions, the class LLViewerTexture can be reached from /llrender.
+//
+class LLTexture : public LLRefCount
+{
+	friend class LLTexUnit ;
+	friend class LLFontGL ;
+
+protected:
+	virtual ~LLTexture();
+
+public:
+	LLTexture(){}
+
+	//
+	//interfaces to access LLViewerTexture
+	//
+	virtual bool       bindDefaultImage(const S32 stage = 0) const = 0 ;
+	virtual void       forceImmediateUpdate() = 0 ;
+	virtual void       setActive() = 0 ;
+	virtual S32	       getWidth(S32 discard_level = -1) const = 0 ;
+	virtual S32	       getHeight(S32 discard_level = -1) const = 0 ;
+
+private:
+	//note: do not make this function public.
+	virtual LLImageGL* getGLTexture() const = 0 ;
+
+	virtual void updateBindStatsForTester() = 0 ;
+};
+#endif
+