llgl.cpp

/** 
 * @file llgl.cpp
 * @brief LLGL implementation
 *
 * $LicenseInfo:firstyear=2001&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

// This file sets some global GL parameters, and implements some 
// useful functions for GL operations.

#define GLH_EXT_SINGLE_FILE

#include "linden_common.h"

#include "boost/tokenizer.hpp"

#include "llsys.h"

#include "llgl.h"
#include "llrender.h"

#include "llerror.h"
#include "llerrorcontrol.h"
#include "llquaternion.h"
#include "llmath.h"
#include "m4math.h"
#include "llstring.h"
#include "llmemtype.h"
#include "llstacktrace.h"

#include "llglheaders.h"

#ifdef _DEBUG
//#define GL_STATE_VERIFY
#endif


BOOL gDebugSession = FALSE;
BOOL gDebugGL = FALSE;
BOOL gClothRipple = FALSE;
BOOL gHeadlessClient = FALSE;
BOOL gGLActive = FALSE;

static const std::string HEADLESS_VENDOR_STRING("Linden Lab");
static const std::string HEADLESS_RENDERER_STRING("Headless");
static const std::string HEADLESS_VERSION_STRING("1.0");

std::ofstream gFailLog;

void ll_init_fail_log(std::string filename)
{
	gFailLog.open(filename.c_str());
}


void ll_fail(std::string msg)
{
	
	if (gDebugSession)
	{
		std::vector<std::string> lines;

		gFailLog << LLError::utcTime() << " " << msg << std::endl;

		gFailLog << "Stack Trace:" << std::endl;

		ll_get_stack_trace(lines);
		
		for(size_t i = 0; i < lines.size(); ++i)
		{
			gFailLog << lines[i] << std::endl;
		}

		gFailLog << "End of Stack Trace." << std::endl << std::endl;

		gFailLog.flush();
	}
};

void ll_close_fail_log()
{
	gFailLog.close();
}

LLMatrix4 gGLObliqueProjectionInverse;

#define LL_GL_NAME_POOLING 0

std::list<LLGLUpdate*> LLGLUpdate::sGLQ;

#if (LL_WINDOWS || LL_LINUX || LL_SOLARIS)  && !LL_MESA_HEADLESS
// ATI prototypes
// vertex blending prototypes
PFNGLWEIGHTPOINTERARBPROC			glWeightPointerARB = NULL;
PFNGLVERTEXBLENDARBPROC				glVertexBlendARB = NULL;
PFNGLWEIGHTFVARBPROC				glWeightfvARB = NULL;

// Vertex buffer object prototypes
PFNGLBINDBUFFERARBPROC				glBindBufferARB = NULL;
PFNGLDELETEBUFFERSARBPROC			glDeleteBuffersARB = NULL;
PFNGLGENBUFFERSARBPROC				glGenBuffersARB = NULL;
PFNGLISBUFFERARBPROC				glIsBufferARB = NULL;
PFNGLBUFFERDATAARBPROC				glBufferDataARB = NULL;
PFNGLBUFFERSUBDATAARBPROC			glBufferSubDataARB = NULL;
PFNGLGETBUFFERSUBDATAARBPROC		glGetBufferSubDataARB = NULL;
PFNGLMAPBUFFERARBPROC				glMapBufferARB = NULL;
PFNGLUNMAPBUFFERARBPROC				glUnmapBufferARB = NULL;
PFNGLGETBUFFERPARAMETERIVARBPROC	glGetBufferParameterivARB = NULL;
PFNGLGETBUFFERPOINTERVARBPROC		glGetBufferPointervARB = NULL;

// vertex object prototypes
PFNGLNEWOBJECTBUFFERATIPROC			glNewObjectBufferATI = NULL;
PFNGLISOBJECTBUFFERATIPROC			glIsObjectBufferATI = NULL;
PFNGLUPDATEOBJECTBUFFERATIPROC		glUpdateObjectBufferATI = NULL;
PFNGLGETOBJECTBUFFERFVATIPROC		glGetObjectBufferfvATI = NULL;
PFNGLGETOBJECTBUFFERIVATIPROC		glGetObjectBufferivATI = NULL;
PFNGLFREEOBJECTBUFFERATIPROC		glFreeObjectBufferATI = NULL;
PFNGLARRAYOBJECTATIPROC				glArrayObjectATI = NULL;
PFNGLVERTEXATTRIBARRAYOBJECTATIPROC	glVertexAttribArrayObjectATI = NULL;
PFNGLGETARRAYOBJECTFVATIPROC		glGetArrayObjectfvATI = NULL;
PFNGLGETARRAYOBJECTIVATIPROC		glGetArrayObjectivATI = NULL;
PFNGLVARIANTARRAYOBJECTATIPROC		glVariantObjectArrayATI = NULL;
PFNGLGETVARIANTARRAYOBJECTFVATIPROC	glGetVariantArrayObjectfvATI = NULL;
PFNGLGETVARIANTARRAYOBJECTIVATIPROC	glGetVariantArrayObjectivATI = NULL;

// GL_ARB_occlusion_query
PFNGLGENQUERIESARBPROC glGenQueriesARB = NULL;
PFNGLDELETEQUERIESARBPROC glDeleteQueriesARB = NULL;
PFNGLISQUERYARBPROC glIsQueryARB = NULL;
PFNGLBEGINQUERYARBPROC glBeginQueryARB = NULL;
PFNGLENDQUERYARBPROC glEndQueryARB = NULL;
PFNGLGETQUERYIVARBPROC glGetQueryivARB = NULL;
PFNGLGETQUERYOBJECTIVARBPROC glGetQueryObjectivARB = NULL;
PFNGLGETQUERYOBJECTUIVARBPROC glGetQueryObjectuivARB = NULL;

// GL_ARB_point_parameters
PFNGLPOINTPARAMETERFARBPROC glPointParameterfARB = NULL;
PFNGLPOINTPARAMETERFVARBPROC glPointParameterfvARB = NULL;

// GL_ARB_framebuffer_object
PFNGLISRENDERBUFFERPROC glIsRenderbuffer = NULL;
PFNGLBINDRENDERBUFFERPROC glBindRenderbuffer = NULL;
PFNGLDELETERENDERBUFFERSPROC glDeleteRenderbuffers = NULL;
PFNGLGENRENDERBUFFERSPROC glGenRenderbuffers = NULL;
PFNGLRENDERBUFFERSTORAGEPROC glRenderbufferStorage = NULL;
PFNGLGETRENDERBUFFERPARAMETERIVPROC glGetRenderbufferParameteriv = NULL;
PFNGLISFRAMEBUFFERPROC glIsFramebuffer = NULL;
PFNGLBINDFRAMEBUFFERPROC glBindFramebuffer = NULL;
PFNGLDELETEFRAMEBUFFERSPROC glDeleteFramebuffers = NULL;
PFNGLGENFRAMEBUFFERSPROC glGenFramebuffers = NULL;
PFNGLCHECKFRAMEBUFFERSTATUSPROC glCheckFramebufferStatus = NULL;
PFNGLFRAMEBUFFERTEXTURE1DPROC glFramebufferTexture1D = NULL;
PFNGLFRAMEBUFFERTEXTURE2DPROC glFramebufferTexture2D = NULL;
PFNGLFRAMEBUFFERTEXTURE3DPROC glFramebufferTexture3D = NULL;
PFNGLFRAMEBUFFERRENDERBUFFERPROC glFramebufferRenderbuffer = NULL;
PFNGLGETFRAMEBUFFERATTACHMENTPARAMETERIVPROC glGetFramebufferAttachmentParameteriv = NULL;
PFNGLGENERATEMIPMAPPROC glGenerateMipmap = NULL;
PFNGLBLITFRAMEBUFFERPROC glBlitFramebuffer = NULL;
PFNGLRENDERBUFFERSTORAGEMULTISAMPLEPROC glRenderbufferStorageMultisample = NULL;
PFNGLFRAMEBUFFERTEXTURELAYERPROC glFramebufferTextureLayer = NULL;

// GL_EXT_blend_func_separate
PFNGLBLENDFUNCSEPARATEEXTPROC glBlendFuncSeparateEXT = NULL;

// GL_ARB_draw_buffers
PFNGLDRAWBUFFERSARBPROC glDrawBuffersARB = NULL;

//shader object prototypes
PFNGLDELETEOBJECTARBPROC glDeleteObjectARB = NULL;
PFNGLGETHANDLEARBPROC glGetHandleARB = NULL;
PFNGLDETACHOBJECTARBPROC glDetachObjectARB = NULL;
PFNGLCREATESHADEROBJECTARBPROC glCreateShaderObjectARB = NULL;
PFNGLSHADERSOURCEARBPROC glShaderSourceARB = NULL;
PFNGLCOMPILESHADERARBPROC glCompileShaderARB = NULL;
PFNGLCREATEPROGRAMOBJECTARBPROC glCreateProgramObjectARB = NULL;
PFNGLATTACHOBJECTARBPROC glAttachObjectARB = NULL;
PFNGLLINKPROGRAMARBPROC glLinkProgramARB = NULL;
PFNGLUSEPROGRAMOBJECTARBPROC glUseProgramObjectARB = NULL;
PFNGLVALIDATEPROGRAMARBPROC glValidateProgramARB = NULL;
PFNGLUNIFORM1FARBPROC glUniform1fARB = NULL;
PFNGLUNIFORM2FARBPROC glUniform2fARB = NULL;
PFNGLUNIFORM3FARBPROC glUniform3fARB = NULL;
PFNGLUNIFORM4FARBPROC glUniform4fARB = NULL;
PFNGLUNIFORM1IARBPROC glUniform1iARB = NULL;
PFNGLUNIFORM2IARBPROC glUniform2iARB = NULL;
PFNGLUNIFORM3IARBPROC glUniform3iARB = NULL;
PFNGLUNIFORM4IARBPROC glUniform4iARB = NULL;
PFNGLUNIFORM1FVARBPROC glUniform1fvARB = NULL;
PFNGLUNIFORM2FVARBPROC glUniform2fvARB = NULL;
PFNGLUNIFORM3FVARBPROC glUniform3fvARB = NULL;
PFNGLUNIFORM4FVARBPROC glUniform4fvARB = NULL;
PFNGLUNIFORM1IVARBPROC glUniform1ivARB = NULL;
PFNGLUNIFORM2IVARBPROC glUniform2ivARB = NULL;
PFNGLUNIFORM3IVARBPROC glUniform3ivARB = NULL;
PFNGLUNIFORM4IVARBPROC glUniform4ivARB = NULL;
PFNGLUNIFORMMATRIX2FVARBPROC glUniformMatrix2fvARB = NULL;
PFNGLUNIFORMMATRIX3FVARBPROC glUniformMatrix3fvARB = NULL;
PFNGLUNIFORMMATRIX4FVARBPROC glUniformMatrix4fvARB = NULL;
PFNGLGETOBJECTPARAMETERFVARBPROC glGetObjectParameterfvARB = NULL;
PFNGLGETOBJECTPARAMETERIVARBPROC glGetObjectParameterivARB = NULL;
PFNGLGETINFOLOGARBPROC glGetInfoLogARB = NULL;
PFNGLGETATTACHEDOBJECTSARBPROC glGetAttachedObjectsARB = NULL;
PFNGLGETUNIFORMLOCATIONARBPROC glGetUniformLocationARB = NULL;
PFNGLGETACTIVEUNIFORMARBPROC glGetActiveUniformARB = NULL;
PFNGLGETUNIFORMFVARBPROC glGetUniformfvARB = NULL;
PFNGLGETUNIFORMIVARBPROC glGetUniformivARB = NULL;
PFNGLGETSHADERSOURCEARBPROC glGetShaderSourceARB = NULL;

// vertex shader prototypes
#if LL_LINUX || LL_SOLARIS
PFNGLVERTEXATTRIB1DARBPROC glVertexAttrib1dARB = NULL;
PFNGLVERTEXATTRIB1DVARBPROC glVertexAttrib1dvARB = NULL;
PFNGLVERTEXATTRIB1FARBPROC glVertexAttrib1fARB = NULL;
PFNGLVERTEXATTRIB1FVARBPROC glVertexAttrib1fvARB = NULL;
PFNGLVERTEXATTRIB1SARBPROC glVertexAttrib1sARB = NULL;
PFNGLVERTEXATTRIB1SVARBPROC glVertexAttrib1svARB = NULL;
PFNGLVERTEXATTRIB2DARBPROC glVertexAttrib2dARB = NULL;
PFNGLVERTEXATTRIB2DVARBPROC glVertexAttrib2dvARB = NULL;
PFNGLVERTEXATTRIB2FARBPROC glVertexAttrib2fARB = NULL;
PFNGLVERTEXATTRIB2FVARBPROC glVertexAttrib2fvARB = NULL;
PFNGLVERTEXATTRIB2SARBPROC glVertexAttrib2sARB = NULL;
PFNGLVERTEXATTRIB2SVARBPROC glVertexAttrib2svARB = NULL;
PFNGLVERTEXATTRIB3DARBPROC glVertexAttrib3dARB = NULL;
PFNGLVERTEXATTRIB3DVARBPROC glVertexAttrib3dvARB = NULL;
PFNGLVERTEXATTRIB3FARBPROC glVertexAttrib3fARB = NULL;
PFNGLVERTEXATTRIB3FVARBPROC glVertexAttrib3fvARB = NULL;
PFNGLVERTEXATTRIB3SARBPROC glVertexAttrib3sARB = NULL;
PFNGLVERTEXATTRIB3SVARBPROC glVertexAttrib3svARB = NULL;
#endif // LL_LINUX || LL_SOLARIS
PFNGLVERTEXATTRIB4NBVARBPROC glVertexAttrib4nbvARB = NULL;
PFNGLVERTEXATTRIB4NIVARBPROC glVertexAttrib4nivARB = NULL;
PFNGLVERTEXATTRIB4NSVARBPROC glVertexAttrib4nsvARB = NULL;
PFNGLVERTEXATTRIB4NUBARBPROC glVertexAttrib4nubARB = NULL;
PFNGLVERTEXATTRIB4NUBVARBPROC glVertexAttrib4nubvARB = NULL;
PFNGLVERTEXATTRIB4NUIVARBPROC glVertexAttrib4nuivARB = NULL;
PFNGLVERTEXATTRIB4NUSVARBPROC glVertexAttrib4nusvARB = NULL;
#if LL_LINUX  || LL_SOLARIS
PFNGLVERTEXATTRIB4BVARBPROC glVertexAttrib4bvARB = NULL;
PFNGLVERTEXATTRIB4DARBPROC glVertexAttrib4dARB = NULL;
PFNGLVERTEXATTRIB4DVARBPROC glVertexAttrib4dvARB = NULL;
PFNGLVERTEXATTRIB4FARBPROC glVertexAttrib4fARB = NULL;
PFNGLVERTEXATTRIB4FVARBPROC glVertexAttrib4fvARB = NULL;
PFNGLVERTEXATTRIB4IVARBPROC glVertexAttrib4ivARB = NULL;
PFNGLVERTEXATTRIB4SARBPROC glVertexAttrib4sARB = NULL;
PFNGLVERTEXATTRIB4SVARBPROC glVertexAttrib4svARB = NULL;
PFNGLVERTEXATTRIB4UBVARBPROC glVertexAttrib4ubvARB = NULL;
PFNGLVERTEXATTRIB4UIVARBPROC glVertexAttrib4uivARB = NULL;
PFNGLVERTEXATTRIB4USVARBPROC glVertexAttrib4usvARB = NULL;
PFNGLVERTEXATTRIBPOINTERARBPROC glVertexAttribPointerARB = NULL;
PFNGLENABLEVERTEXATTRIBARRAYARBPROC glEnableVertexAttribArrayARB = NULL;
PFNGLDISABLEVERTEXATTRIBARRAYARBPROC glDisableVertexAttribArrayARB = NULL;
PFNGLPROGRAMSTRINGARBPROC glProgramStringARB = NULL;
PFNGLBINDPROGRAMARBPROC glBindProgramARB = NULL;
PFNGLDELETEPROGRAMSARBPROC glDeleteProgramsARB = NULL;
PFNGLGENPROGRAMSARBPROC glGenProgramsARB = NULL;
PFNGLPROGRAMENVPARAMETER4DARBPROC glProgramEnvParameter4dARB = NULL;
PFNGLPROGRAMENVPARAMETER4DVARBPROC glProgramEnvParameter4dvARB = NULL;
PFNGLPROGRAMENVPARAMETER4FARBPROC glProgramEnvParameter4fARB = NULL;
PFNGLPROGRAMENVPARAMETER4FVARBPROC glProgramEnvParameter4fvARB = NULL;
PFNGLPROGRAMLOCALPARAMETER4DARBPROC glProgramLocalParameter4dARB = NULL;
PFNGLPROGRAMLOCALPARAMETER4DVARBPROC glProgramLocalParameter4dvARB = NULL;
PFNGLPROGRAMLOCALPARAMETER4FARBPROC glProgramLocalParameter4fARB = NULL;
PFNGLPROGRAMLOCALPARAMETER4FVARBPROC glProgramLocalParameter4fvARB = NULL;
PFNGLGETPROGRAMENVPARAMETERDVARBPROC glGetProgramEnvParameterdvARB = NULL;
PFNGLGETPROGRAMENVPARAMETERFVARBPROC glGetProgramEnvParameterfvARB = NULL;
PFNGLGETPROGRAMLOCALPARAMETERDVARBPROC glGetProgramLocalParameterdvARB = NULL;
PFNGLGETPROGRAMLOCALPARAMETERFVARBPROC glGetProgramLocalParameterfvARB = NULL;
PFNGLGETPROGRAMIVARBPROC glGetProgramivARB = NULL;
PFNGLGETPROGRAMSTRINGARBPROC glGetProgramStringARB = NULL;
PFNGLGETVERTEXATTRIBDVARBPROC glGetVertexAttribdvARB = NULL;
PFNGLGETVERTEXATTRIBFVARBPROC glGetVertexAttribfvARB = NULL;
PFNGLGETVERTEXATTRIBIVARBPROC glGetVertexAttribivARB = NULL;
PFNGLGETVERTEXATTRIBPOINTERVARBPROC glGetVertexAttribPointervARB = NULL;
PFNGLISPROGRAMARBPROC glIsProgramARB = NULL;
#endif // LL_LINUX || LL_SOLARIS
PFNGLBINDATTRIBLOCATIONARBPROC glBindAttribLocationARB = NULL;
PFNGLGETACTIVEATTRIBARBPROC glGetActiveAttribARB = NULL;
PFNGLGETATTRIBLOCATIONARBPROC glGetAttribLocationARB = NULL;

#if LL_WINDOWS
PFNWGLSWAPINTERVALEXTPROC			wglSwapIntervalEXT = NULL;
#endif

#if LL_LINUX_NV_GL_HEADERS
// linux nvidia headers.  these define these differently to mesa's.  ugh.
PFNGLACTIVETEXTUREARBPROC glActiveTextureARB = NULL;
PFNGLCLIENTACTIVETEXTUREARBPROC glClientActiveTextureARB = NULL;
PFNGLDRAWRANGEELEMENTSPROC glDrawRangeElements = NULL;
#endif // LL_LINUX_NV_GL_HEADERS
#endif

LLGLManager gGLManager;

LLGLManager::LLGLManager() :
	mInited(FALSE),
	mIsDisabled(FALSE),

	mHasMultitexture(FALSE),
	mHasATIMemInfo(FALSE),
	mHasNVXMemInfo(FALSE),
	mNumTextureUnits(1),
	mHasMipMapGeneration(FALSE),
	mHasCompressedTextures(FALSE),
	mHasFramebufferObject(FALSE),
	mHasBlendFuncSeparate(FALSE),

	mHasVertexBufferObject(FALSE),
	mHasPBuffer(FALSE),
	mHasShaderObjects(FALSE),
	mHasVertexShader(FALSE),
	mHasFragmentShader(FALSE),
	mHasOcclusionQuery(FALSE),
	mHasOcclusionQuery2(FALSE),
	mHasPointParameters(FALSE),
	mHasDrawBuffers(FALSE),
	mHasTextureRectangle(FALSE),

	mHasAnisotropic(FALSE),
	mHasARBEnvCombine(FALSE),
	mHasCubeMap(FALSE),

	mIsATI(FALSE),
	mIsNVIDIA(FALSE),
	mIsIntel(FALSE),
	mIsGF2or4MX(FALSE),
	mIsGF3(FALSE),
	mIsGFFX(FALSE),
	mATIOffsetVerticalLines(FALSE),
	mATIOldDriver(FALSE),

	mHasRequirements(TRUE),

	mHasSeparateSpecularColor(FALSE),

	mDebugGPU(FALSE),

	mDriverVersionMajor(1),
	mDriverVersionMinor(0),
	mDriverVersionRelease(0),
	mGLVersion(1.0f),
		
	mVRAM(0),
	mGLMaxVertexRange(0),
	mGLMaxIndexRange(0)
{
}

//---------------------------------------------------------------------
// Global initialization for GL
//---------------------------------------------------------------------
void LLGLManager::initWGL()
{
	mHasPBuffer = FALSE;
#if LL_WINDOWS && !LL_MESA_HEADLESS
	if (!glh_init_extensions("WGL_ARB_pixel_format"))
	{
		LL_WARNS("RenderInit") << "No ARB pixel format extensions" << LL_ENDL;
	}

	if (ExtensionExists("WGL_EXT_swap_control", gGLHExts.mSysExts))
	{
        GLH_EXT_NAME(wglSwapIntervalEXT) = (PFNWGLSWAPINTERVALEXTPROC)GLH_EXT_GET_PROC_ADDRESS("wglSwapIntervalEXT");
	}

	if( !glh_init_extensions("WGL_ARB_pbuffer") )
	{
		LL_WARNS("RenderInit") << "No ARB WGL PBuffer extensions" << LL_ENDL;
	}

	if( !glh_init_extensions("WGL_ARB_render_texture") )
	{
		LL_WARNS("RenderInit") << "No ARB WGL render texture extensions" << LL_ENDL;
	}

	mHasPBuffer = ExtensionExists("WGL_ARB_pbuffer", gGLHExts.mSysExts) &&
					ExtensionExists("WGL_ARB_render_texture", gGLHExts.mSysExts) &&
					ExtensionExists("WGL_ARB_pixel_format", gGLHExts.mSysExts);
#endif
}

// return false if unable (or unwilling due to old drivers) to init GL
bool LLGLManager::initGL()
{
	if (mInited)
	{
		LL_ERRS("RenderInit") << "Calling init on LLGLManager after already initialized!" << LL_ENDL;
	}

	GLint alpha_bits;
	glGetIntegerv( GL_ALPHA_BITS, &alpha_bits );
	if( 8 != alpha_bits )
	{
		LL_WARNS("RenderInit") << "Frame buffer has less than 8 bits of alpha.  Avatar texture compositing will fail." << LL_ENDL;
	}

	// Extract video card strings and convert to upper case to
	// work around driver-to-driver variation in capitalization.
	mGLVendor = std::string((const char *)glGetString(GL_VENDOR));
	LLStringUtil::toUpper(mGLVendor);

	mGLRenderer = std::string((const char *)glGetString(GL_RENDERER));
	LLStringUtil::toUpper(mGLRenderer);

	parse_gl_version( &mDriverVersionMajor, 
		&mDriverVersionMinor, 
		&mDriverVersionRelease, 
		&mDriverVersionVendorString );

	mGLVersion = mDriverVersionMajor + mDriverVersionMinor * .1f;
	
	// Trailing space necessary to keep "nVidia Corpor_ati_on" cards
	// from being recognized as ATI.
	if (mGLVendor.substr(0,4) == "ATI ")
	{
		mGLVendorShort = "ATI";
		BOOL mobile = FALSE;
		if (mGLRenderer.find("MOBILITY") != std::string::npos)
		{
			mobile = TRUE;
		}
		mIsATI = TRUE;

#if LL_WINDOWS && !LL_MESA_HEADLESS
		if (mDriverVersionRelease < 3842)
		{
			mATIOffsetVerticalLines = TRUE;
		}
#endif // LL_WINDOWS

#if (LL_WINDOWS || LL_LINUX) && !LL_MESA_HEADLESS
		// release 7277 is a point at which we verify that ATI OpenGL
		// drivers get pretty stable with SL, ~Catalyst 8.2,
		// for both Win32 and Linux.
		if (mDriverVersionRelease < 7277 &&
		    mDriverVersionRelease != 0) // 0 == Undetectable driver version - these get to pretend to be new ATI drivers, though that decision may be revisited.
		{
			mATIOldDriver = TRUE;
		}
#endif // (LL_WINDOWS || LL_LINUX) && !LL_MESA_HEADLESS
	}
	else if (mGLVendor.find("NVIDIA ") != std::string::npos)
	{
		mGLVendorShort = "NVIDIA";
		mIsNVIDIA = TRUE;
		if (   mGLRenderer.find("GEFORCE4 MX") != std::string::npos
			|| mGLRenderer.find("GEFORCE2") != std::string::npos
			|| mGLRenderer.find("GEFORCE 2") != std::string::npos
			|| mGLRenderer.find("GEFORCE4 460 GO") != std::string::npos
			|| mGLRenderer.find("GEFORCE4 440 GO") != std::string::npos
			|| mGLRenderer.find("GEFORCE4 420 GO") != std::string::npos)
		{
			mIsGF2or4MX = TRUE;
		}
		else if (mGLRenderer.find("GEFORCE FX") != std::string::npos
				 || mGLRenderer.find("QUADRO FX") != std::string::npos
				 || mGLRenderer.find("NV34") != std::string::npos)
		{
			mIsGFFX = TRUE;
		}
		else if(mGLRenderer.find("GEFORCE3") != std::string::npos)
		{
			mIsGF3 = TRUE;
		}

	}
	else if (mGLVendor.find("INTEL") != std::string::npos
#if LL_LINUX
		 // The Mesa-based drivers put this in the Renderer string,
		 // not the Vendor string.
		 || mGLRenderer.find("INTEL") != std::string::npos
#endif //LL_LINUX
		 )
	{
		mGLVendorShort = "INTEL";
		mIsIntel = TRUE;
	}
	else
	{
		mGLVendorShort = "MISC";
	}
	
	// This is called here because it depends on the setting of mIsGF2or4MX, and sets up mHasMultitexture.
	initExtensions();

	if (mHasATIMemInfo)
	{ //ask the gl how much vram is free at startup and attempt to use no more than half of that
		S32 meminfo[4];
		glGetIntegerv(GL_TEXTURE_FREE_MEMORY_ATI, meminfo);

		mVRAM = meminfo[0]/1024;
	}
	else if (mHasNVXMemInfo)
	{
		S32 dedicated_memory;
		glGetIntegerv(GL_GPU_MEMORY_INFO_DEDICATED_VIDMEM_NVX, &dedicated_memory);
		mVRAM = dedicated_memory/1024;
	}

	if (mHasMultitexture)
	{
		GLint num_tex_units;		
		glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &num_tex_units);
		mNumTextureUnits = llmin(num_tex_units, (GLint)MAX_GL_TEXTURE_UNITS);
		if (mIsIntel)
		{
			mNumTextureUnits = llmin(mNumTextureUnits, 2);
		}
	}
	else
	{
		mHasRequirements = FALSE;

		// We don't support cards that don't support the GL_ARB_multitexture extension
		LL_WARNS("RenderInit") << "GL Drivers do not support GL_ARB_multitexture" << LL_ENDL;
		return false;
	}
	
	setToDebugGPU();

	initGLStates();
	return true;
}

void LLGLManager::setToDebugGPU()
{
	//"MOBILE INTEL(R) 965 EXPRESS CHIP", 
	if (mGLRenderer.find("INTEL") != std::string::npos && mGLRenderer.find("965") != std::string::npos)
	{
		mDebugGPU = TRUE ;
	}

	return ;
}

void LLGLManager::getGLInfo(LLSD& info)
{
	if (gHeadlessClient)
	{
		info["GLInfo"]["GLVendor"] = HEADLESS_VENDOR_STRING;
		info["GLInfo"]["GLRenderer"] = HEADLESS_RENDERER_STRING;
		info["GLInfo"]["GLVersion"] = HEADLESS_VERSION_STRING;
		return;
	}
	else
	{
		info["GLInfo"]["GLVendor"] = std::string((const char *)glGetString(GL_VENDOR));
		info["GLInfo"]["GLRenderer"] = std::string((const char *)glGetString(GL_RENDERER));
		info["GLInfo"]["GLVersion"] = std::string((const char *)glGetString(GL_VERSION));
	}

#if !LL_MESA_HEADLESS
	std::string all_exts = ll_safe_string((const char *)gGLHExts.mSysExts);
	boost::char_separator<char> sep(" ");
	boost::tokenizer<boost::char_separator<char> > tok(all_exts, sep);
	for(boost::tokenizer<boost::char_separator<char> >::iterator i = tok.begin(); i != tok.end(); ++i)
	{
		info["GLInfo"]["GLExtensions"].append(*i);
	}
#endif
}

std::string LLGLManager::getGLInfoString()
{
	std::string info_str;

	if (gHeadlessClient)
	{
		info_str += std::string("GL_VENDOR      ") + HEADLESS_VENDOR_STRING + std::string("\n");
		info_str += std::string("GL_RENDERER    ") + HEADLESS_RENDERER_STRING + std::string("\n");
		info_str += std::string("GL_VERSION     ") + HEADLESS_VERSION_STRING + std::string("\n");
	}
	else
	{
		info_str += std::string("GL_VENDOR      ") + ll_safe_string((const char *)glGetString(GL_VENDOR)) + std::string("\n");
		info_str += std::string("GL_RENDERER    ") + ll_safe_string((const char *)glGetString(GL_RENDERER)) + std::string("\n");
		info_str += std::string("GL_VERSION     ") + ll_safe_string((const char *)glGetString(GL_VERSION)) + std::string("\n");
	}

#if !LL_MESA_HEADLESS 
	std::string all_exts= ll_safe_string(((const char *)gGLHExts.mSysExts));
	LLStringUtil::replaceChar(all_exts, ' ', '\n');
	info_str += std::string("GL_EXTENSIONS:\n") + all_exts + std::string("\n");
#endif
	
	return info_str;
}

void LLGLManager::printGLInfoString()
{
	if (gHeadlessClient)
	{
		LL_INFOS("RenderInit") << "GL_VENDOR:     " << HEADLESS_VENDOR_STRING << LL_ENDL;
		LL_INFOS("RenderInit") << "GL_RENDERER:   " << HEADLESS_RENDERER_STRING << LL_ENDL;
		LL_INFOS("RenderInit") << "GL_VERSION:    " << HEADLESS_VERSION_STRING << LL_ENDL;
	}
	else
	{
		LL_INFOS("RenderInit") << "GL_VENDOR:     " << ((const char *)glGetString(GL_VENDOR)) << LL_ENDL;
		LL_INFOS("RenderInit") << "GL_RENDERER:   " << ((const char *)glGetString(GL_RENDERER)) << LL_ENDL;
		LL_INFOS("RenderInit") << "GL_VERSION:    " << ((const char *)glGetString(GL_VERSION)) << LL_ENDL;
	}

#if !LL_MESA_HEADLESS
	std::string all_exts= ll_safe_string(((const char *)gGLHExts.mSysExts));
	LLStringUtil::replaceChar(all_exts, ' ', '\n');
	LL_DEBUGS("RenderInit") << "GL_EXTENSIONS:\n" << all_exts << LL_ENDL;
#endif
}

std::string LLGLManager::getRawGLString()
{
	std::string gl_string;
	if (gHeadlessClient)
	{
		gl_string = HEADLESS_VENDOR_STRING + " " + HEADLESS_RENDERER_STRING;
	}
	else
	{
		gl_string = ll_safe_string((char*)glGetString(GL_VENDOR)) + " " + ll_safe_string((char*)glGetString(GL_RENDERER));
	}
	return gl_string;
}

void LLGLManager::shutdownGL()
{
	if (mInited)
	{
		glFinish();
		stop_glerror();
		mInited = FALSE;
	}
}

// these are used to turn software blending on. They appear in the Debug/Avatar menu
// presence of vertex skinning/blending or vertex programs will set these to FALSE by default.

void LLGLManager::initExtensions()
{
#if LL_MESA_HEADLESS
# ifdef GL_ARB_multitexture
	mHasMultitexture = TRUE;
# else
	mHasMultitexture = FALSE;
# endif // GL_ARB_multitexture
# ifdef GL_ARB_texture_env_combine
	mHasARBEnvCombine = TRUE;	
# else
	mHasARBEnvCombine = FALSE;
# endif // GL_ARB_texture_env_combine
# ifdef GL_ARB_texture_compression
	mHasCompressedTextures = TRUE;
# else
	mHasCompressedTextures = FALSE;
# endif // GL_ARB_texture_compression
# ifdef GL_ARB_vertex_buffer_object
	mHasVertexBufferObject = TRUE;
# else
	mHasVertexBufferObject = FALSE;
# endif // GL_ARB_vertex_buffer_object
# ifdef GL_EXT_framebuffer_object
	mHasFramebufferObject = TRUE;
# else
	mHasFramebufferObject = FALSE;
# endif // GL_EXT_framebuffer_object
# ifdef GL_ARB_draw_buffers
	mHasDrawBuffers = TRUE;
#else
	mHasDrawBuffers = FALSE;
# endif // GL_ARB_draw_buffers
# if defined(GL_NV_depth_clamp) || defined(GL_ARB_depth_clamp)
	mHasDepthClamp = TRUE;
#else
	mHasDepthClamp = FALSE;
#endif // defined(GL_NV_depth_clamp) || defined(GL_ARB_depth_clamp)
# if GL_EXT_blend_func_separate
	mHasBlendFuncSeparate = TRUE;
#else
	mHasBlendFuncSeparate = FALSE;
# endif // GL_EXT_blend_func_separate
	mHasMipMapGeneration = FALSE;
	mHasSeparateSpecularColor = FALSE;
	mHasAnisotropic = FALSE;
	mHasCubeMap = FALSE;
	mHasOcclusionQuery = FALSE;
	mHasPointParameters = FALSE;
	mHasShaderObjects = FALSE;
	mHasVertexShader = FALSE;
	mHasFragmentShader = FALSE;
	mHasTextureRectangle = FALSE;
#else // LL_MESA_HEADLESS
	mHasMultitexture = glh_init_extensions("GL_ARB_multitexture");
	mHasATIMemInfo = ExtensionExists("GL_ATI_meminfo", gGLHExts.mSysExts);
	mHasNVXMemInfo = ExtensionExists("GL_NVX_gpu_memory_info", gGLHExts.mSysExts);
	mHasMipMapGeneration = glh_init_extensions("GL_SGIS_generate_mipmap");
	mHasSeparateSpecularColor = glh_init_extensions("GL_EXT_separate_specular_color");
	mHasAnisotropic = glh_init_extensions("GL_EXT_texture_filter_anisotropic");
	glh_init_extensions("GL_ARB_texture_cube_map");
	mHasCubeMap = ExtensionExists("GL_ARB_texture_cube_map", gGLHExts.mSysExts);
	mHasARBEnvCombine = ExtensionExists("GL_ARB_texture_env_combine", gGLHExts.mSysExts);
	mHasCompressedTextures = glh_init_extensions("GL_ARB_texture_compression");
	mHasOcclusionQuery = ExtensionExists("GL_ARB_occlusion_query", gGLHExts.mSysExts);
	mHasOcclusionQuery2 = ExtensionExists("GL_ARB_occlusion_query2", gGLHExts.mSysExts);
	mHasVertexBufferObject = ExtensionExists("GL_ARB_vertex_buffer_object", gGLHExts.mSysExts);
	mHasDepthClamp = ExtensionExists("GL_ARB_depth_clamp", gGLHExts.mSysExts) || ExtensionExists("GL_NV_depth_clamp", gGLHExts.mSysExts);
	// mask out FBO support when packed_depth_stencil isn't there 'cause we need it for LLRenderTarget -Brad
#ifdef GL_ARB_framebuffer_object
	mHasFramebufferObject = ExtensionExists("GL_ARB_framebuffer_object", gGLHExts.mSysExts);
#else
	mHasFramebufferObject = ExtensionExists("GL_EXT_framebuffer_object", gGLHExts.mSysExts) &&
							ExtensionExists("GL_EXT_framebuffer_blit", gGLHExts.mSysExts) &&
							ExtensionExists("GL_EXT_framebuffer_multisample", gGLHExts.mSysExts) &&
							ExtensionExists("GL_EXT_packed_depth_stencil", gGLHExts.mSysExts);
#endif
	
	mHasDrawBuffers = ExtensionExists("GL_ARB_draw_buffers", gGLHExts.mSysExts);
	mHasBlendFuncSeparate = ExtensionExists("GL_EXT_blend_func_separate", gGLHExts.mSysExts);
	mHasTextureRectangle = ExtensionExists("GL_ARB_texture_rectangle", gGLHExts.mSysExts);
#if !LL_DARWIN
	mHasPointParameters = !mIsATI && ExtensionExists("GL_ARB_point_parameters", gGLHExts.mSysExts);
#endif
	mHasShaderObjects = ExtensionExists("GL_ARB_shader_objects", gGLHExts.mSysExts) && ExtensionExists("GL_ARB_shading_language_100", gGLHExts.mSysExts);
	mHasVertexShader = ExtensionExists("GL_ARB_vertex_program", gGLHExts.mSysExts) && ExtensionExists("GL_ARB_vertex_shader", gGLHExts.mSysExts)
						&& ExtensionExists("GL_ARB_shading_language_100", gGLHExts.mSysExts);
	mHasFragmentShader = ExtensionExists("GL_ARB_fragment_shader", gGLHExts.mSysExts) && ExtensionExists("GL_ARB_shading_language_100", gGLHExts.mSysExts);
#endif

#if LL_LINUX || LL_SOLARIS
	llinfos << "initExtensions() checking shell variables to adjust features..." << llendl;
	// Our extension support for the Linux Client is very young with some
	// potential driver gotchas, so offer a semi-secret way to turn it off.
	if (getenv("LL_GL_NOEXT"))
	{
		//mHasMultitexture = FALSE; // NEEDED!
		mHasDepthClamp = FALSE;
		mHasARBEnvCombine = FALSE;
		mHasCompressedTextures = FALSE;
		mHasVertexBufferObject = FALSE;
		mHasFramebufferObject = FALSE;
		mHasDrawBuffers = FALSE;
		mHasBlendFuncSeparate = FALSE;
		mHasMipMapGeneration = FALSE;
		mHasSeparateSpecularColor = FALSE;
		mHasAnisotropic = FALSE;
		mHasCubeMap = FALSE;
		mHasOcclusionQuery = FALSE;
		mHasPointParameters = FALSE;
		mHasShaderObjects = FALSE;
		mHasVertexShader = FALSE;
		mHasFragmentShader = FALSE;
		LL_WARNS("RenderInit") << "GL extension support DISABLED via LL_GL_NOEXT" << LL_ENDL;
	}
	else if (getenv("LL_GL_BASICEXT"))	/* Flawfinder: ignore */
	{
		// This switch attempts to turn off all support for exotic
		// extensions which I believe correspond to fatal driver
		// bug reports.  This should be the default until we get a
		// proper blacklist/whitelist on Linux.
		mHasMipMapGeneration = FALSE;
		mHasAnisotropic = FALSE;
		//mHasCubeMap = FALSE; // apparently fatal on Intel 915 & similar
		//mHasOcclusionQuery = FALSE; // source of many ATI system hangs
		mHasShaderObjects = FALSE;
		mHasVertexShader = FALSE;
		mHasFragmentShader = FALSE;
		mHasBlendFuncSeparate = FALSE;
		LL_WARNS("RenderInit") << "GL extension support forced to SIMPLE level via LL_GL_BASICEXT" << LL_ENDL;
	}
	if (getenv("LL_GL_BLACKLIST"))	/* Flawfinder: ignore */
	{
		// This lets advanced troubleshooters disable specific
		// GL extensions to isolate problems with their hardware.
		// SL-28126
		const char *const blacklist = getenv("LL_GL_BLACKLIST");	/* Flawfinder: ignore */
		LL_WARNS("RenderInit") << "GL extension support partially disabled via LL_GL_BLACKLIST: " << blacklist << LL_ENDL;
		if (strchr(blacklist,'a')) mHasARBEnvCombine = FALSE;
		if (strchr(blacklist,'b')) mHasCompressedTextures = FALSE;
		if (strchr(blacklist,'c')) mHasVertexBufferObject = FALSE;
		if (strchr(blacklist,'d')) mHasMipMapGeneration = FALSE;//S
// 		if (strchr(blacklist,'f')) mHasNVVertexArrayRange = FALSE;//S
// 		if (strchr(blacklist,'g')) mHasNVFence = FALSE;//S
		if (strchr(blacklist,'h')) mHasSeparateSpecularColor = FALSE;
		if (strchr(blacklist,'i')) mHasAnisotropic = FALSE;//S
		if (strchr(blacklist,'j')) mHasCubeMap = FALSE;//S
// 		if (strchr(blacklist,'k')) mHasATIVAO = FALSE;//S
		if (strchr(blacklist,'l')) mHasOcclusionQuery = FALSE;
		if (strchr(blacklist,'m')) mHasShaderObjects = FALSE;//S
		if (strchr(blacklist,'n')) mHasVertexShader = FALSE;//S
		if (strchr(blacklist,'o')) mHasFragmentShader = FALSE;//S
		if (strchr(blacklist,'p')) mHasPointParameters = FALSE;//S
		if (strchr(blacklist,'q')) mHasFramebufferObject = FALSE;//S
		if (strchr(blacklist,'r')) mHasDrawBuffers = FALSE;//S
		if (strchr(blacklist,'s')) mHasTextureRectangle = FALSE;
		if (strchr(blacklist,'t')) mHasBlendFuncSeparate = FALSE;//S
		if (strchr(blacklist,'u')) mHasDepthClamp = FALSE;
		
	}
#endif // LL_LINUX || LL_SOLARIS
	
	if (!mHasMultitexture)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize multitexturing" << LL_ENDL;
	}
	if (!mHasMipMapGeneration)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize mipmap generation" << LL_ENDL;
	}
	if (!mHasARBEnvCombine)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_texture_env_combine" << LL_ENDL;
	}
	if (!mHasSeparateSpecularColor)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize separate specular color" << LL_ENDL;
	}
	if (!mHasAnisotropic)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize anisotropic filtering" << LL_ENDL;
	}
	if (!mHasCompressedTextures)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_texture_compression" << LL_ENDL;
	}
	if (!mHasOcclusionQuery)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_occlusion_query" << LL_ENDL;
	}
	if (!mHasOcclusionQuery2)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_occlusion_query2" << LL_ENDL;
	}
	if (!mHasPointParameters)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_point_parameters" << LL_ENDL;
	}
	if (!mHasShaderObjects)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_shader_objects" << LL_ENDL;
	}
	if (!mHasVertexShader)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_vertex_shader" << LL_ENDL;
	}
	if (!mHasFragmentShader)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_fragment_shader" << LL_ENDL;
	}
	if (!mHasBlendFuncSeparate)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_EXT_blend_func_separate" << LL_ENDL;
	}
	if (!mHasDrawBuffers)
	{
		LL_INFOS("RenderInit") << "Couldn't initialize GL_ARB_draw_buffers" << LL_ENDL;
	}

	// Disable certain things due to known bugs
	if (mIsIntel && mHasMipMapGeneration)
	{
		LL_INFOS("RenderInit") << "Disabling mip-map generation for Intel GPUs" << LL_ENDL;
		mHasMipMapGeneration = FALSE;
	}
	if (mIsATI && mHasMipMapGeneration)
	{
		LL_INFOS("RenderInit") << "Disabling mip-map generation for ATI GPUs (performance opt)" << LL_ENDL;
		mHasMipMapGeneration = FALSE;
	}
	
	// Misc
	glGetIntegerv(GL_MAX_ELEMENTS_VERTICES, (GLint*) &mGLMaxVertexRange);
	glGetIntegerv(GL_MAX_ELEMENTS_INDICES, (GLint*) &mGLMaxIndexRange);
	
#if (LL_WINDOWS || LL_LINUX || LL_SOLARIS) && !LL_MESA_HEADLESS
	LL_DEBUGS("RenderInit") << "GL Probe: Getting symbols" << LL_ENDL;
	if (mHasVertexBufferObject)
	{
		glBindBufferARB = (PFNGLBINDBUFFERARBPROC)GLH_EXT_GET_PROC_ADDRESS("glBindBufferARB");
		if (glBindBufferARB)
		{
			glDeleteBuffersARB = (PFNGLDELETEBUFFERSARBPROC)GLH_EXT_GET_PROC_ADDRESS("glDeleteBuffersARB");
			glGenBuffersARB = (PFNGLGENBUFFERSARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGenBuffersARB");
			glIsBufferARB = (PFNGLISBUFFERARBPROC)GLH_EXT_GET_PROC_ADDRESS("glIsBufferARB");
			glBufferDataARB = (PFNGLBUFFERDATAARBPROC)GLH_EXT_GET_PROC_ADDRESS("glBufferDataARB");
			glBufferSubDataARB = (PFNGLBUFFERSUBDATAARBPROC)GLH_EXT_GET_PROC_ADDRESS("glBufferSubDataARB");
			glGetBufferSubDataARB = (PFNGLGETBUFFERSUBDATAARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetBufferSubDataARB");
			glMapBufferARB = (PFNGLMAPBUFFERARBPROC)GLH_EXT_GET_PROC_ADDRESS("glMapBufferARB");
			glUnmapBufferARB = (PFNGLUNMAPBUFFERARBPROC)GLH_EXT_GET_PROC_ADDRESS("glUnmapBufferARB");
			glGetBufferParameterivARB = (PFNGLGETBUFFERPARAMETERIVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetBufferParameterivARB");
			glGetBufferPointervARB = (PFNGLGETBUFFERPOINTERVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetBufferPointervARB");
		}
		else
		{
			mHasVertexBufferObject = FALSE;
		}
	}
	if (mHasFramebufferObject)
	{
		llinfos << "initExtensions() FramebufferObject-related procs..." << llendl;
		glIsRenderbuffer = (PFNGLISRENDERBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glIsRenderbuffer");
		glBindRenderbuffer = (PFNGLBINDRENDERBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glBindRenderbuffer");
		glDeleteRenderbuffers = (PFNGLDELETERENDERBUFFERSPROC) GLH_EXT_GET_PROC_ADDRESS("glDeleteRenderbuffers");
		glGenRenderbuffers = (PFNGLGENRENDERBUFFERSPROC) GLH_EXT_GET_PROC_ADDRESS("glGenRenderbuffers");
		glRenderbufferStorage = (PFNGLRENDERBUFFERSTORAGEPROC) GLH_EXT_GET_PROC_ADDRESS("glRenderbufferStorage");
		glGetRenderbufferParameteriv = (PFNGLGETRENDERBUFFERPARAMETERIVPROC) GLH_EXT_GET_PROC_ADDRESS("glGetRenderbufferParameteriv");
		glIsFramebuffer = (PFNGLISFRAMEBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glIsFramebuffer");
		glBindFramebuffer = (PFNGLBINDFRAMEBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glBindFramebuffer");
		glDeleteFramebuffers = (PFNGLDELETEFRAMEBUFFERSPROC) GLH_EXT_GET_PROC_ADDRESS("glDeleteFramebuffers");
		glGenFramebuffers = (PFNGLGENFRAMEBUFFERSPROC) GLH_EXT_GET_PROC_ADDRESS("glGenFramebuffers");
		glCheckFramebufferStatus = (PFNGLCHECKFRAMEBUFFERSTATUSPROC) GLH_EXT_GET_PROC_ADDRESS("glCheckFramebufferStatus");
		glFramebufferTexture1D = (PFNGLFRAMEBUFFERTEXTURE1DPROC) GLH_EXT_GET_PROC_ADDRESS("glFramebufferTexture1D");
		glFramebufferTexture2D = (PFNGLFRAMEBUFFERTEXTURE2DPROC) GLH_EXT_GET_PROC_ADDRESS("glFramebufferTexture2D");
		glFramebufferTexture3D = (PFNGLFRAMEBUFFERTEXTURE3DPROC) GLH_EXT_GET_PROC_ADDRESS("glFramebufferTexture3D");
		glFramebufferRenderbuffer = (PFNGLFRAMEBUFFERRENDERBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glFramebufferRenderbuffer");
		glGetFramebufferAttachmentParameteriv = (PFNGLGETFRAMEBUFFERATTACHMENTPARAMETERIVPROC) GLH_EXT_GET_PROC_ADDRESS("glGetFramebufferAttachmentParameteriv");
		glGenerateMipmap = (PFNGLGENERATEMIPMAPPROC) GLH_EXT_GET_PROC_ADDRESS("glGenerateMipmap");
		glBlitFramebuffer = (PFNGLBLITFRAMEBUFFERPROC) GLH_EXT_GET_PROC_ADDRESS("glBlitFramebuffer");
		glRenderbufferStorageMultisample = (PFNGLRENDERBUFFERSTORAGEMULTISAMPLEPROC) GLH_EXT_GET_PROC_ADDRESS("glRenderbufferStorageMultisample");
		glFramebufferTextureLayer = (PFNGLFRAMEBUFFERTEXTURELAYERPROC) GLH_EXT_GET_PROC_ADDRESS("glFramebufferTextureLayer");
	}
	if (mHasDrawBuffers)
	{
		glDrawBuffersARB = (PFNGLDRAWBUFFERSARBPROC) GLH_EXT_GET_PROC_ADDRESS("glDrawBuffersARB");
	}
	if (mHasBlendFuncSeparate)
	{
		glBlendFuncSeparateEXT = (PFNGLBLENDFUNCSEPARATEEXTPROC) GLH_EXT_GET_PROC_ADDRESS("glBlendFuncSeparateEXT");
	}
#if (!LL_LINUX && !LL_SOLARIS) || LL_LINUX_NV_GL_HEADERS
	// This is expected to be a static symbol on Linux GL implementations, except if we use the nvidia headers - bah
	glDrawRangeElements = (PFNGLDRAWRANGEELEMENTSPROC)GLH_EXT_GET_PROC_ADDRESS("glDrawRangeElements");
	if (!glDrawRangeElements)
	{
		mGLMaxVertexRange = 0;
		mGLMaxIndexRange = 0;
	}
#endif // !LL_LINUX || LL_LINUX_NV_GL_HEADERS
#if LL_LINUX_NV_GL_HEADERS
	// nvidia headers are critically different from mesa-esque
 	glActiveTextureARB = (PFNGLACTIVETEXTUREARBPROC)GLH_EXT_GET_PROC_ADDRESS("glActiveTextureARB");
 	glClientActiveTextureARB = (PFNGLCLIENTACTIVETEXTUREARBPROC)GLH_EXT_GET_PROC_ADDRESS("glClientActiveTextureARB");
#endif // LL_LINUX_NV_GL_HEADERS

	if (mHasOcclusionQuery)
	{
		llinfos << "initExtensions() OcclusionQuery-related procs..." << llendl;
		glGenQueriesARB = (PFNGLGENQUERIESARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGenQueriesARB");
		glDeleteQueriesARB = (PFNGLDELETEQUERIESARBPROC)GLH_EXT_GET_PROC_ADDRESS("glDeleteQueriesARB");
		glIsQueryARB = (PFNGLISQUERYARBPROC)GLH_EXT_GET_PROC_ADDRESS("glIsQueryARB");
		glBeginQueryARB = (PFNGLBEGINQUERYARBPROC)GLH_EXT_GET_PROC_ADDRESS("glBeginQueryARB");
		glEndQueryARB = (PFNGLENDQUERYARBPROC)GLH_EXT_GET_PROC_ADDRESS("glEndQueryARB");
		glGetQueryivARB = (PFNGLGETQUERYIVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetQueryivARB");
		glGetQueryObjectivARB = (PFNGLGETQUERYOBJECTIVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetQueryObjectivARB");
		glGetQueryObjectuivARB = (PFNGLGETQUERYOBJECTUIVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glGetQueryObjectuivARB");
	}
	if (mHasPointParameters)
	{
		llinfos << "initExtensions() PointParameters-related procs..." << llendl;
		glPointParameterfARB = (PFNGLPOINTPARAMETERFARBPROC)GLH_EXT_GET_PROC_ADDRESS("glPointParameterfARB");
		glPointParameterfvARB = (PFNGLPOINTPARAMETERFVARBPROC)GLH_EXT_GET_PROC_ADDRESS("glPointParameterfvARB");
	}
	if (mHasShaderObjects)
	{
		glDeleteObjectARB = (PFNGLDELETEOBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glDeleteObjectARB");
		glGetHandleARB = (PFNGLGETHANDLEARBPROC) GLH_EXT_GET_PROC_ADDRESS("glGetHandleARB");
		glDetachObjectARB = (PFNGLDETACHOBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glDetachObjectARB");
		glCreateShaderObjectARB = (PFNGLCREATESHADEROBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glCreateShaderObjectARB");
		glShaderSourceARB = (PFNGLSHADERSOURCEARBPROC) GLH_EXT_GET_PROC_ADDRESS("glShaderSourceARB");
		glCompileShaderARB = (PFNGLCOMPILESHADERARBPROC) GLH_EXT_GET_PROC_ADDRESS("glCompileShaderARB");
		glCreateProgramObjectARB = (PFNGLCREATEPROGRAMOBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glCreateProgramObjectARB");
		glAttachObjectARB = (PFNGLATTACHOBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glAttachObjectARB");
		glLinkProgramARB = (PFNGLLINKPROGRAMARBPROC) GLH_EXT_GET_PROC_ADDRESS("glLinkProgramARB");
		glUseProgramObjectARB = (PFNGLUSEPROGRAMOBJECTARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUseProgramObjectARB");
		glValidateProgramARB = (PFNGLVALIDATEPROGRAMARBPROC) GLH_EXT_GET_PROC_ADDRESS("glValidateProgramARB");
		glUniform1fARB = (PFNGLUNIFORM1FARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform1fARB");
		glUniform2fARB = (PFNGLUNIFORM2FARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform2fARB");
		glUniform3fARB = (PFNGLUNIFORM3FARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform3fARB");
		glUniform4fARB = (PFNGLUNIFORM4FARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform4fARB");
		glUniform1iARB = (PFNGLUNIFORM1IARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform1iARB");
		glUniform2iARB = (PFNGLUNIFORM2IARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform2iARB");
		glUniform3iARB = (PFNGLUNIFORM3IARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform3iARB");
		glUniform4iARB = (PFNGLUNIFORM4IARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform4iARB");
		glUniform1fvARB = (PFNGLUNIFORM1FVARBPROC) GLH_EXT_GET_PROC_ADDRESS("glUniform1fvARB");