// Created on: 2014-03-17
// Created by: Kirill GAVRILOV
// Copyright (c) 2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#ifndef OpenGl_GlFunctions_HeaderFile
#define OpenGl_GlFunctions_HeaderFile

#include <Standard_Macro.hxx>
#include <Standard_TypeDef.hxx>

#include <OpenGl_GlTypes.hxx>

#if !defined(HAVE_EGL)
#if defined(__ANDROID__) || defined(__QNX__) || defined(__EMSCRIPTEN__) || defined(HAVE_GLES2) || defined(OCCT_UWP)
  #if !defined(__APPLE__)
    #define HAVE_EGL // EAGL is used instead of EGL
  #endif
#elif !defined(_WIN32) && !defined(__APPLE__) && !defined(HAVE_XLIB)
  #define HAVE_EGL
#endif
#endif
struct Aspect_XDisplay;

// GL version can be defined by system gl.h header
#ifdef GL_VERSION_1_2
  #undef GL_VERSION_1_2
  #undef GL_VERSION_1_3
  #undef GL_VERSION_1_4
  #undef GL_VERSION_1_5
  #undef GL_VERSION_2_0
  #undef GL_VERSION_2_1
  #undef GL_VERSION_3_0
  #undef GL_VERSION_3_1
  #undef GL_VERSION_3_2
  #undef GL_VERSION_3_3
  #undef GL_VERSION_4_0
  #undef GL_VERSION_4_1
  #undef GL_VERSION_4_2
  #undef GL_VERSION_4_3
  #undef GL_VERSION_4_4
  #undef GL_VERSION_4_5
#endif
#ifdef GL_COPY_READ_BUFFER_BINDING
  // suppress iOS SDK -Wmacro-redefined warnings
  #undef GL_DRAW_FRAMEBUFFER_BINDING
  #undef GL_COPY_READ_BUFFER_BINDING
  #undef GL_COPY_WRITE_BUFFER_BINDING
#endif
// include glext.h provided by Khronos group
#include <OpenGl_glext.h>

class OpenGl_Context;

//! Mega structure defines the complete list of OpenGL functions.
struct OpenGl_GlFunctions
{

  //! Check glGetError(); defined for debugging purposes.
  //! @return TRUE on error
  Standard_EXPORT static bool debugPrintError (const char* theName);

  //! Read OpenGL version.
  Standard_EXPORT static void readGlVersion (Standard_Integer& theGlVerMajor,
                                             Standard_Integer& theGlVerMinor);

  //! Load functions.
  Standard_EXPORT void load (OpenGl_Context& theCtx,
                             Standard_Boolean theIsCoreProfile);

public: //! @name OpenGL 1.1

  typedef void (APIENTRYP glClearColor_t)(GLclampf theRed, GLclampf theGreen, GLclampf theBlue, GLclampf theAlpha);
  glClearColor_t glClearColor;

  typedef void (APIENTRYP glClear_t)(GLbitfield theMask);
  glClear_t glClear;

  typedef void (APIENTRYP glColorMask_t)(GLboolean theRed, GLboolean theGreen, GLboolean theBlue, GLboolean theAlpha);
  glColorMask_t glColorMask;

  typedef void (APIENTRYP glBlendFunc_t)(GLenum sfactor, GLenum dfactor);
  glBlendFunc_t glBlendFunc;

  typedef void (APIENTRYP glCullFace_t)(GLenum theMode);
  glCullFace_t glCullFace;

  typedef void (APIENTRYP glFrontFace_t)(GLenum theMode);
  glFrontFace_t glFrontFace;

  typedef void (APIENTRYP glLineWidth_t)(GLfloat theWidth);
  glLineWidth_t glLineWidth;

  typedef void (APIENTRYP glPolygonOffset_t)(GLfloat theFactor, GLfloat theUnits);
  glPolygonOffset_t glPolygonOffset;

  typedef void (APIENTRYP glScissor_t)(GLint theX, GLint theY, GLsizei theWidth, GLsizei theHeight);
  glScissor_t glScissor;

  typedef void (APIENTRYP glEnable_t)(GLenum theCap);
  glEnable_t glEnable;

  typedef void (APIENTRYP glDisable_t)(GLenum theCap);
  glDisable_t glDisable;

  typedef GLboolean (APIENTRYP glIsEnabled_t)(GLenum theCap);
  glIsEnabled_t glIsEnabled;

  typedef void (APIENTRYP glGetBooleanv_t)(GLenum theParamName, GLboolean* theValues);
  glGetBooleanv_t glGetBooleanv;

  typedef void (APIENTRYP glGetFloatv_t)(GLenum theParamName, GLfloat* theValues);
  glGetFloatv_t glGetFloatv;

  typedef void (APIENTRYP glGetIntegerv_t)(GLenum theParamName, GLint* theValues);
  glGetIntegerv_t glGetIntegerv;

  typedef GLenum (APIENTRYP glGetError_t)();
  glGetError_t glGetError;

  typedef const GLubyte* (APIENTRYP glGetString_t)(GLenum theName);
  glGetString_t glGetString;

  typedef void (APIENTRYP glFinish_t)();
  glFinish_t glFinish;

  typedef void (APIENTRYP glFlush_t)();
  glFlush_t glFlush;

  typedef void (APIENTRYP glHint_t)(GLenum theTarget, GLenum theMode);
  glHint_t glHint;

  typedef void (APIENTRYP glGetPointerv_t)(GLenum pname, GLvoid* *params);
  glGetPointerv_t glGetPointerv;

  typedef void (APIENTRYP glReadBuffer_t)(GLenum src); // added to OpenGL ES 3.0
  glReadBuffer_t glReadBuffer;

  typedef void (APIENTRYP glDrawBuffer_t)(GLenum mode); // added to OpenGL ES 3.0
  glDrawBuffer_t glDrawBuffer;

  typedef void (APIENTRYP glPixelTransferi_t)(GLenum pname, GLint param);
  glPixelTransferi_t glPixelTransferi;

public: //! @name Depth Buffer

  typedef void (APIENTRYP glClearDepth_t)(GLclampd theDepth);
  glClearDepth_t glClearDepth;

  typedef void (APIENTRYP glDepthFunc_t)(GLenum theFunc);
  glDepthFunc_t glDepthFunc;

  typedef void (APIENTRYP glDepthMask_t)(GLboolean theFlag);
  glDepthMask_t glDepthMask;

  typedef void (APIENTRYP glDepthRange_t)(GLclampd theNearValue, GLclampd theFarValue);
  glDepthRange_t glDepthRange;

public: //! @name Transformation

  typedef void (APIENTRYP glViewport_t)(GLint theX, GLint theY, GLsizei theWidth, GLsizei theHeight);
  glViewport_t glViewport;

public: //! @name Vertex Arrays

  typedef void (APIENTRYP glDrawArrays_t)(GLenum theMode, GLint theFirst, GLsizei theCount);
  glDrawArrays_t glDrawArrays;

  typedef void (APIENTRYP glDrawElements_t)(GLenum theMode, GLsizei theCount, GLenum theType, const GLvoid* theIndices);
  glDrawElements_t glDrawElements;

public: //! @name Raster functions

  typedef void (APIENTRYP glPixelStorei_t)(GLenum theParamName, GLint theParam);
  glPixelStorei_t glPixelStorei;

  typedef void (APIENTRYP glReadPixels_t)(GLint x, GLint y,
                                          GLsizei width, GLsizei height,
                                          GLenum format, GLenum type,
                                          GLvoid* pixels);
  glReadPixels_t glReadPixels;

public: //! @name Stenciling

  typedef void (APIENTRYP glStencilFunc_t)(GLenum func, GLint ref, GLuint mask);
  glStencilFunc_t glStencilFunc;

  typedef void (APIENTRYP glStencilMask_t)(GLuint mask);
  glStencilMask_t glStencilMask;

  typedef void (APIENTRYP glStencilOp_t)(GLenum fail, GLenum zfail, GLenum zpass);
  glStencilOp_t glStencilOp;

  typedef void (APIENTRYP glClearStencil_t)(GLint s);
  glClearStencil_t glClearStencil;

public: //! @name Texture mapping

  typedef void (APIENTRYP glTexParameterf_t)(GLenum target, GLenum pname, GLfloat param);
  glTexParameterf_t glTexParameterf;

  typedef void (APIENTRYP glTexParameteri_t)(GLenum target, GLenum pname, GLint param);
  glTexParameteri_t glTexParameteri;

  typedef void (APIENTRYP glTexParameterfv_t)(GLenum target, GLenum pname, const GLfloat* params);
  glTexParameterfv_t glTexParameterfv;

  typedef void (APIENTRYP glTexParameteriv_t)(GLenum target, GLenum pname, const GLint* params);
  glTexParameteriv_t glTexParameteriv;

  typedef void (APIENTRYP glGetTexParameterfv_t)(GLenum target, GLenum pname, GLfloat* params);
  glGetTexParameterfv_t glGetTexParameterfv;

  typedef void (APIENTRYP glGetTexParameteriv_t)(GLenum target, GLenum pname, GLint* params);
  glGetTexParameteriv_t glGetTexParameteriv;

  typedef void (APIENTRYP glTexImage2D_t)(GLenum target, GLint level,
                                          GLint internalFormat,
                                          GLsizei width, GLsizei height,
                                          GLint border, GLenum format, GLenum type,
                                          const GLvoid* pixels);
  glTexImage2D_t glTexImage2D;

  typedef void (APIENTRYP glGenTextures_t)(GLsizei n, GLuint* textures);
  glGenTextures_t glGenTextures;

  typedef void (APIENTRYP glDeleteTextures_t)(GLsizei n, const GLuint* textures);
  glDeleteTextures_t glDeleteTextures;

  typedef void (APIENTRYP glBindTexture_t)(GLenum target, GLuint texture);
  glBindTexture_t glBindTexture;

  typedef GLboolean (APIENTRYP glIsTexture_t)(GLuint texture);
  glIsTexture_t glIsTexture;

  typedef void (APIENTRYP glTexSubImage2D_t)(GLenum target, GLint level,
                                             GLint xoffset, GLint yoffset,
                                             GLsizei width, GLsizei height,
                                             GLenum format, GLenum type,
                                             const GLvoid* pixels);
  glTexSubImage2D_t glTexSubImage2D;

  typedef void (APIENTRYP glCopyTexImage2D_t)(GLenum target, GLint level,
                                              GLenum internalformat,
                                              GLint x, GLint y,
                                              GLsizei width, GLsizei height,
                                              GLint border);
  glCopyTexImage2D_t glCopyTexImage2D;

  typedef void (APIENTRYP glCopyTexSubImage2D_t)(GLenum target, GLint level,
                                                 GLint xoffset, GLint yoffset,
                                                 GLint x, GLint y,
                                                 GLsizei width, GLsizei height);
  glCopyTexSubImage2D_t glCopyTexSubImage2D;

public: // not part of OpenGL ES 2.0
  typedef void (APIENTRYP glTexImage1D_t)(GLenum target, GLint level,
                                          GLint internalFormat,
                                          GLsizei width, GLint border,
                                          GLenum format, GLenum type,
                                          const GLvoid* pixels);
  glTexImage1D_t glTexImage1D;

  typedef void (APIENTRYP glTexSubImage1D_t)(GLenum target, GLint level,
                                             GLint xoffset,
                                             GLsizei width, GLenum format,
                                             GLenum type, const GLvoid* pixels);
  glTexSubImage1D_t glTexSubImage1D;

  typedef void (APIENTRYP glCopyTexImage1D_t)(GLenum target, GLint level,
                                              GLenum internalformat,
                                              GLint x, GLint y,
                                              GLsizei width, GLint border);
  glCopyTexImage1D_t glCopyTexImage1D;

  typedef void (APIENTRYP glCopyTexSubImage1D_t)(GLenum target, GLint level,
                                                 GLint xoffset, GLint x, GLint y,
                                                 GLsizei width);
  glCopyTexSubImage1D_t glCopyTexSubImage1D;

  typedef void (APIENTRYP glGetTexImage_t)(GLenum target, GLint level,
                                           GLenum format, GLenum type,
                                           GLvoid* pixels);
  glGetTexImage_t glGetTexImage;

  typedef void (APIENTRYP glAlphaFunc_t)(GLenum theFunc, GLclampf theRef);
  glAlphaFunc_t glAlphaFunc;

  typedef void (APIENTRYP glPointSize_t)(GLfloat theSize);
  glPointSize_t glPointSize;

public: //! @name OpenGL 1.1 FFP (obsolete, removed since 3.1)

  typedef void (APIENTRYP glTexEnvi_t)(GLenum target, GLenum pname, GLint param);
  glTexEnvi_t glTexEnvi;

  typedef void (APIENTRYP glGetTexEnviv_t)(GLenum target, GLenum pname, GLint *params);
  glGetTexEnviv_t glGetTexEnviv;

  typedef void (APIENTRYP glLogicOp_t)(GLenum opcode);
  glLogicOp_t glLogicOp;

public: //! @name Begin/End primitive specification (removed since 3.1)

  typedef void (APIENTRYP glColor4fv_t)(const GLfloat* theVec);
  glColor4fv_t glColor4fv;

public: //! @name Matrix operations (removed since 3.1)

  typedef void (APIENTRYP glMatrixMode_t)(GLenum theMode);
  glMatrixMode_t glMatrixMode;

  typedef void (APIENTRYP glLoadIdentity_t)();
  glLoadIdentity_t glLoadIdentity;

  typedef void (APIENTRYP glLoadMatrixf_t)(const GLfloat* theMatrix);
  glLoadMatrixf_t glLoadMatrixf;

public: //! @name Line and Polygon stipple (removed since 3.1)

  typedef void (APIENTRYP glLineStipple_t)(GLint theFactor, GLushort thePattern);
  glLineStipple_t glLineStipple;

  typedef void (APIENTRYP glPolygonStipple_t)(const GLubyte* theMask);
  glPolygonStipple_t glPolygonStipple;

public: //! @name Fixed pipeline lighting (removed since 3.1)

  typedef void (APIENTRYP glShadeModel_t)(GLenum theMode);
  glShadeModel_t glShadeModel;

  typedef void (APIENTRYP glLightf_t)(GLenum theLight, GLenum pname, GLfloat param);
  glLightf_t glLightf;

  typedef void (APIENTRYP glLightfv_t)(GLenum theLight, GLenum pname, const GLfloat* params);
  glLightfv_t glLightfv;

  typedef void (APIENTRYP glLightModeli_t)(GLenum pname, GLint param);
  glLightModeli_t glLightModeli;

  typedef void (APIENTRYP glLightModelfv_t)(GLenum pname, const GLfloat* params);
  glLightModelfv_t glLightModelfv;

  typedef void (APIENTRYP glMaterialf_t)(GLenum face, GLenum pname, GLfloat param);
  glMaterialf_t glMaterialf;

  typedef void (APIENTRYP glMaterialfv_t)(GLenum face, GLenum pname, const GLfloat* params);
  glMaterialfv_t glMaterialfv;

  typedef void (APIENTRYP glColorMaterial_t)(GLenum face, GLenum mode);
  glColorMaterial_t glColorMaterial;

public: //! @name clipping plane (removed since 3.1)

  typedef void (APIENTRYP glClipPlane_t)(GLenum thePlane, const GLdouble* theEquation);
  glClipPlane_t glClipPlane;

public: //! @name Display lists (removed since 3.1)

  typedef void (APIENTRYP glDeleteLists_t)(GLuint theList, GLsizei theRange);
  glDeleteLists_t glDeleteLists;

  typedef GLuint (APIENTRYP glGenLists_t)(GLsizei theRange);
  glGenLists_t glGenLists;

  typedef void (APIENTRYP glNewList_t)(GLuint theList, GLenum theMode);
  glNewList_t glNewList;

  typedef void (APIENTRYP glEndList_t)();
  glEndList_t glEndList;

  typedef void (APIENTRYP glCallList_t)(GLuint theList);
  glCallList_t glCallList;

  typedef void (APIENTRYP glCallLists_t)(GLsizei theNb, GLenum theType, const GLvoid* theLists);
  glCallLists_t glCallLists;

  typedef void (APIENTRYP glListBase_t)(GLuint theBase);
  glListBase_t glListBase;

public: //! @name Current raster position and Rectangles (removed since 3.1)

  typedef void (APIENTRYP glRasterPos2i_t)(GLint x, GLint y);
  glRasterPos2i_t glRasterPos2i;

  typedef void (APIENTRYP glRasterPos3fv_t)(const GLfloat*  theVec);
  glRasterPos3fv_t glRasterPos3fv;

public: //! @name Texture mapping (removed since 3.1)

  typedef void (APIENTRYP glTexGeni_t)(GLenum coord, GLenum pname, GLint param);
  glTexGeni_t glTexGeni;

  typedef void (APIENTRYP glTexGenfv_t)(GLenum coord, GLenum pname, const GLfloat* params);
  glTexGenfv_t glTexGenfv;

public: //! @name Pixel copying (removed since 3.1)

  typedef void (APIENTRYP glDrawPixels_t)(GLsizei width, GLsizei height,
                                          GLenum format, GLenum type,
                                          const GLvoid* pixels);
  glDrawPixels_t glDrawPixels;

  typedef void (APIENTRYP glCopyPixels_t)(GLint x, GLint y,
                                          GLsizei width, GLsizei height,
                                          GLenum type);
  glCopyPixels_t glCopyPixels;

  typedef void (APIENTRYP glBitmap_t)(GLsizei width, GLsizei height,
                                      GLfloat xorig, GLfloat yorig,
                                      GLfloat xmove, GLfloat ymove,
                                      const GLubyte* bitmap);
  glBitmap_t glBitmap;

public: //! @name Edge flags and fixed-function vertex processing (removed since 3.1)

  typedef void (APIENTRYP glIndexPointer_t)(GLenum theType, GLsizei theStride, const GLvoid* thePtr);
  glIndexPointer_t glIndexPointer;

  typedef void (APIENTRYP glVertexPointer_t)(GLint theSize, GLenum theType, GLsizei theStride, const GLvoid* thePtr);
  glVertexPointer_t glVertexPointer;

  typedef void (APIENTRYP glNormalPointer_t)(GLenum theType, GLsizei theStride, const GLvoid* thePtr);
  glNormalPointer_t glNormalPointer;

  typedef void (APIENTRYP glColorPointer_t)(GLint theSize, GLenum theType, GLsizei theStride, const GLvoid* thePtr);
  glColorPointer_t glColorPointer;

  typedef void (APIENTRYP glTexCoordPointer_t)(GLint theSize, GLenum theType, GLsizei theStride, const GLvoid* thePtr);
  glTexCoordPointer_t glTexCoordPointer;

  typedef void (APIENTRYP glEnableClientState_t)(GLenum theCap);
  glEnableClientState_t glEnableClientState;

  typedef void (APIENTRYP glDisableClientState_t)(GLenum theCap);
  glDisableClientState_t glDisableClientState;

  typedef void (APIENTRYP glGetTexLevelParameterfv_t)(GLenum target, GLint level, GLenum pname, GLfloat *params);
  glGetTexLevelParameterfv_t glGetTexLevelParameterfv;

  typedef void (APIENTRYP glGetTexLevelParameteriv_t)(GLenum target, GLint level, GLenum pname, GLint *params);
  glGetTexLevelParameteriv_t glGetTexLevelParameteriv;

  typedef void (APIENTRYP glPolygonMode_t)(GLenum face, GLenum mode);
  glPolygonMode_t glPolygonMode;

public: //! @name OpenGL ES 3.2
  typedef void (APIENTRYP glBlendBarrier_t) (void);
  glBlendBarrier_t glBlendBarrier;

  typedef void (APIENTRYP glPrimitiveBoundingBox_t) (GLfloat minX, GLfloat minY, GLfloat minZ, GLfloat minW, GLfloat maxX, GLfloat maxY, GLfloat maxZ, GLfloat maxW);
  glPrimitiveBoundingBox_t glPrimitiveBoundingBox;

public: //! @name OpenGL 1.2

  PFNGLBLENDCOLORPROC               glBlendColor;
  PFNGLBLENDEQUATIONPROC            glBlendEquation;
  PFNGLDRAWRANGEELEMENTSPROC        glDrawRangeElements;
  PFNGLTEXIMAGE3DPROC               glTexImage3D;
  PFNGLTEXSUBIMAGE3DPROC            glTexSubImage3D;
  PFNGLCOPYTEXSUBIMAGE3DPROC        glCopyTexSubImage3D;

public: //! @name OpenGL 1.3

  PFNGLACTIVETEXTUREPROC            glActiveTexture;
  PFNGLSAMPLECOVERAGEPROC           glSampleCoverage;
  PFNGLCOMPRESSEDTEXIMAGE3DPROC     glCompressedTexImage3D;
  PFNGLCOMPRESSEDTEXIMAGE2DPROC     glCompressedTexImage2D;
  PFNGLCOMPRESSEDTEXIMAGE1DPROC     glCompressedTexImage1D;
  PFNGLCOMPRESSEDTEXSUBIMAGE3DPROC  glCompressedTexSubImage3D;
  PFNGLCOMPRESSEDTEXSUBIMAGE2DPROC  glCompressedTexSubImage2D;
  PFNGLCOMPRESSEDTEXSUBIMAGE1DPROC  glCompressedTexSubImage1D;
  PFNGLGETCOMPRESSEDTEXIMAGEPROC    glGetCompressedTexImage;

public: //! @name OpenGL 1.4

  PFNGLBLENDFUNCSEPARATEPROC        glBlendFuncSeparate;
  PFNGLMULTIDRAWARRAYSPROC          glMultiDrawArrays;
  PFNGLMULTIDRAWELEMENTSPROC        glMultiDrawElements;
  PFNGLPOINTPARAMETERFPROC          glPointParameterf;
  PFNGLPOINTPARAMETERFVPROC         glPointParameterfv;
  PFNGLPOINTPARAMETERIPROC          glPointParameteri;
  PFNGLPOINTPARAMETERIVPROC         glPointParameteriv;

public: //! @name OpenGL 1.5

  PFNGLGENQUERIESPROC               glGenQueries;
  PFNGLDELETEQUERIESPROC            glDeleteQueries;
  PFNGLISQUERYPROC                  glIsQuery;
  PFNGLBEGINQUERYPROC               glBeginQuery;
  PFNGLENDQUERYPROC                 glEndQuery;
  PFNGLGETQUERYIVPROC               glGetQueryiv;
  PFNGLGETQUERYOBJECTIVPROC         glGetQueryObjectiv;
  PFNGLGETQUERYOBJECTUIVPROC        glGetQueryObjectuiv;
  PFNGLBINDBUFFERPROC               glBindBuffer;
  PFNGLDELETEBUFFERSPROC            glDeleteBuffers;
  PFNGLGENBUFFERSPROC               glGenBuffers;
  PFNGLISBUFFERPROC                 glIsBuffer;
  PFNGLBUFFERDATAPROC               glBufferData;
  PFNGLBUFFERSUBDATAPROC            glBufferSubData;
  PFNGLGETBUFFERSUBDATAPROC         glGetBufferSubData;
  PFNGLMAPBUFFERPROC                glMapBuffer;
  PFNGLUNMAPBUFFERPROC              glUnmapBuffer;
  PFNGLGETBUFFERPARAMETERIVPROC     glGetBufferParameteriv;
  PFNGLGETBUFFERPOINTERVPROC        glGetBufferPointerv;

public: //! @name OpenGL 2.0

  PFNGLBLENDEQUATIONSEPARATEPROC    glBlendEquationSeparate;
  PFNGLDRAWBUFFERSPROC              glDrawBuffers;
  PFNGLSTENCILOPSEPARATEPROC        glStencilOpSeparate;
  PFNGLSTENCILFUNCSEPARATEPROC      glStencilFuncSeparate;
  PFNGLSTENCILMASKSEPARATEPROC      glStencilMaskSeparate;
  PFNGLATTACHSHADERPROC             glAttachShader;
  PFNGLBINDATTRIBLOCATIONPROC       glBindAttribLocation;
  PFNGLCOMPILESHADERPROC            glCompileShader;
  PFNGLCREATEPROGRAMPROC            glCreateProgram;
  PFNGLCREATESHADERPROC             glCreateShader;
  PFNGLDELETEPROGRAMPROC            glDeleteProgram;
  PFNGLDELETESHADERPROC             glDeleteShader;
  PFNGLDETACHSHADERPROC             glDetachShader;
  PFNGLDISABLEVERTEXATTRIBARRAYPROC glDisableVertexAttribArray;
  PFNGLENABLEVERTEXATTRIBARRAYPROC  glEnableVertexAttribArray;
  PFNGLGETACTIVEATTRIBPROC          glGetActiveAttrib;
  PFNGLGETACTIVEUNIFORMPROC         glGetActiveUniform;
  PFNGLGETATTACHEDSHADERSPROC       glGetAttachedShaders;
  PFNGLGETATTRIBLOCATIONPROC        glGetAttribLocation;
  PFNGLGETPROGRAMIVPROC             glGetProgramiv;
  PFNGLGETPROGRAMINFOLOGPROC        glGetProgramInfoLog;
  PFNGLGETSHADERIVPROC              glGetShaderiv;
  PFNGLGETSHADERINFOLOGPROC         glGetShaderInfoLog;
  PFNGLGETSHADERSOURCEPROC          glGetShaderSource;
  PFNGLGETUNIFORMLOCATIONPROC       glGetUniformLocation;
  PFNGLGETUNIFORMFVPROC             glGetUniformfv;
  PFNGLGETUNIFORMIVPROC             glGetUniformiv;
  PFNGLGETVERTEXATTRIBDVPROC        glGetVertexAttribdv;
  PFNGLGETVERTEXATTRIBFVPROC        glGetVertexAttribfv;
  PFNGLGETVERTEXATTRIBIVPROC        glGetVertexAttribiv;
  PFNGLGETVERTEXATTRIBPOINTERVPROC  glGetVertexAttribPointerv;
  PFNGLISPROGRAMPROC                glIsProgram;
  PFNGLISSHADERPROC                 glIsShader;
  PFNGLLINKPROGRAMPROC              glLinkProgram;
  PFNGLSHADERSOURCEPROC             glShaderSource;
  PFNGLUSEPROGRAMPROC               glUseProgram;
  PFNGLUNIFORM1FPROC                glUniform1f;
  PFNGLUNIFORM2FPROC                glUniform2f;
  PFNGLUNIFORM3FPROC                glUniform3f;
  PFNGLUNIFORM4FPROC                glUniform4f;
  PFNGLUNIFORM1IPROC                glUniform1i;
  PFNGLUNIFORM2IPROC                glUniform2i;
  PFNGLUNIFORM3IPROC                glUniform3i;
  PFNGLUNIFORM4IPROC                glUniform4i;
  PFNGLUNIFORM1FVPROC               glUniform1fv;
  PFNGLUNIFORM2FVPROC               glUniform2fv;
  PFNGLUNIFORM3FVPROC               glUniform3fv;
  PFNGLUNIFORM4FVPROC               glUniform4fv;
  PFNGLUNIFORM1IVPROC               glUniform1iv;
  PFNGLUNIFORM2IVPROC               glUniform2iv;
  PFNGLUNIFORM3IVPROC               glUniform3iv;
  PFNGLUNIFORM4IVPROC               glUniform4iv;
  PFNGLUNIFORMMATRIX2FVPROC         glUniformMatrix2fv;
  PFNGLUNIFORMMATRIX3FVPROC         glUniformMatrix3fv;
  PFNGLUNIFORMMATRIX4FVPROC         glUniformMatrix4fv;
  PFNGLVALIDATEPROGRAMPROC          glValidateProgram;
  PFNGLVERTEXATTRIB1DPROC           glVertexAttrib1d;
  PFNGLVERTEXATTRIB1DVPROC          glVertexAttrib1dv;
  PFNGLVERTEXATTRIB1FPROC           glVertexAttrib1f;
  PFNGLVERTEXATTRIB1FVPROC          glVertexAttrib1fv;
  PFNGLVERTEXATTRIB1SPROC           glVertexAttrib1s;
  PFNGLVERTEXATTRIB1SVPROC          glVertexAttrib1sv;
  PFNGLVERTEXATTRIB2DPROC           glVertexAttrib2d;
  PFNGLVERTEXATTRIB2DVPROC          glVertexAttrib2dv;
  PFNGLVERTEXATTRIB2FPROC           glVertexAttrib2f;
  PFNGLVERTEXATTRIB2FVPROC          glVertexAttrib2fv;
  PFNGLVERTEXATTRIB2SPROC           glVertexAttrib2s;
  PFNGLVERTEXATTRIB2SVPROC          glVertexAttrib2sv;
  PFNGLVERTEXATTRIB3DPROC           glVertexAttrib3d;
  PFNGLVERTEXATTRIB3DVPROC          glVertexAttrib3dv;
  PFNGLVERTEXATTRIB3FPROC           glVertexAttrib3f;
  PFNGLVERTEXATTRIB3FVPROC          glVertexAttrib3fv;
  PFNGLVERTEXATTRIB3SPROC           glVertexAttrib3s;
  PFNGLVERTEXATTRIB3SVPROC          glVertexAttrib3sv;
  PFNGLVERTEXATTRIB4NBVPROC         glVertexAttrib4Nbv;
  PFNGLVERTEXATTRIB4NIVPROC         glVertexAttrib4Niv;
  PFNGLVERTEXATTRIB4NSVPROC         glVertexAttrib4Nsv;
  PFNGLVERTEXATTRIB4NUBPROC         glVertexAttrib4Nub;
  PFNGLVERTEXATTRIB4NUBVPROC        glVertexAttrib4Nubv;
  PFNGLVERTEXATTRIB4NUIVPROC        glVertexAttrib4Nuiv;
  PFNGLVERTEXATTRIB4NUSVPROC        glVertexAttrib4Nusv;
  PFNGLVERTEXATTRIB4BVPROC          glVertexAttrib4bv;
  PFNGLVERTEXATTRIB4DPROC           glVertexAttrib4d;
  PFNGLVERTEXATTRIB4DVPROC          glVertexAttrib4dv;
  PFNGLVERTEXATTRIB4FPROC           glVertexAttrib4f;
  PFNGLVERTEXATTRIB4FVPROC          glVertexAttrib4fv;
  PFNGLVERTEXATTRIB4IVPROC          glVertexAttrib4iv;
  PFNGLVERTEXATTRIB4SPROC           glVertexAttrib4s;
  PFNGLVERTEXATTRIB4SVPROC          glVertexAttrib4sv;
  PFNGLVERTEXATTRIB4UBVPROC         glVertexAttrib4ubv;
  PFNGLVERTEXATTRIB4UIVPROC         glVertexAttrib4uiv;
  PFNGLVERTEXATTRIB4USVPROC         glVertexAttrib4usv;
  PFNGLVERTEXATTRIBPOINTERPROC      glVertexAttribPointer;

public: //! @name OpenGL 2.1

  PFNGLUNIFORMMATRIX2X3FVPROC       glUniformMatrix2x3fv;
  PFNGLUNIFORMMATRIX3X2FVPROC       glUniformMatrix3x2fv;
  PFNGLUNIFORMMATRIX2X4FVPROC       glUniformMatrix2x4fv;
  PFNGLUNIFORMMATRIX4X2FVPROC       glUniformMatrix4x2fv;
  PFNGLUNIFORMMATRIX3X4FVPROC       glUniformMatrix3x4fv;
  PFNGLUNIFORMMATRIX4X3FVPROC       glUniformMatrix4x3fv;

public: //! @name GL_ARB_framebuffer_object (added to OpenGL 3.0 core)

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

public: //! @name GL_ARB_vertex_array_object (added to OpenGL 3.0 core)

  PFNGLBINDVERTEXARRAYPROC             glBindVertexArray;
  PFNGLDELETEVERTEXARRAYSPROC          glDeleteVertexArrays;
  PFNGLGENVERTEXARRAYSPROC             glGenVertexArrays;
  PFNGLISVERTEXARRAYPROC               glIsVertexArray;

public: //! @name GL_ARB_map_buffer_range (added to OpenGL 3.0 core)

  PFNGLMAPBUFFERRANGEPROC              glMapBufferRange;
  PFNGLFLUSHMAPPEDBUFFERRANGEPROC      glFlushMappedBufferRange;

public: //! @name OpenGL 3.0

  PFNGLCOLORMASKIPROC                  glColorMaski;
  PFNGLGETBOOLEANI_VPROC               glGetBooleani_v;
  PFNGLGETINTEGERI_VPROC               glGetIntegeri_v;
  PFNGLENABLEIPROC                     glEnablei;
  PFNGLDISABLEIPROC                    glDisablei;
  PFNGLISENABLEDIPROC                  glIsEnabledi;
  PFNGLBEGINTRANSFORMFEEDBACKPROC      glBeginTransformFeedback;
  PFNGLENDTRANSFORMFEEDBACKPROC        glEndTransformFeedback;
  PFNGLBINDBUFFERRANGEPROC             glBindBufferRange;
  PFNGLBINDBUFFERBASEPROC              glBindBufferBase;
  PFNGLTRANSFORMFEEDBACKVARYINGSPROC   glTransformFeedbackVaryings;
  PFNGLGETTRANSFORMFEEDBACKVARYINGPROC glGetTransformFeedbackVarying;
  PFNGLCLAMPCOLORPROC                  glClampColor;
  PFNGLBEGINCONDITIONALRENDERPROC      glBeginConditionalRender;
  PFNGLENDCONDITIONALRENDERPROC        glEndConditionalRender;
  PFNGLVERTEXATTRIBIPOINTERPROC        glVertexAttribIPointer;
  PFNGLGETVERTEXATTRIBIIVPROC          glGetVertexAttribIiv;
  PFNGLGETVERTEXATTRIBIUIVPROC         glGetVertexAttribIuiv;
  PFNGLVERTEXATTRIBI1IPROC             glVertexAttribI1i;
  PFNGLVERTEXATTRIBI2IPROC             glVertexAttribI2i;
  PFNGLVERTEXATTRIBI3IPROC             glVertexAttribI3i;
  PFNGLVERTEXATTRIBI4IPROC             glVertexAttribI4i;
  PFNGLVERTEXATTRIBI1UIPROC            glVertexAttribI1ui;
  PFNGLVERTEXATTRIBI2UIPROC            glVertexAttribI2ui;
  PFNGLVERTEXATTRIBI3UIPROC            glVertexAttribI3ui;
  PFNGLVERTEXATTRIBI4UIPROC            glVertexAttribI4ui;
  PFNGLVERTEXATTRIBI1IVPROC            glVertexAttribI1iv;
  PFNGLVERTEXATTRIBI2IVPROC            glVertexAttribI2iv;
  PFNGLVERTEXATTRIBI3IVPROC            glVertexAttribI3iv;
  PFNGLVERTEXATTRIBI4IVPROC            glVertexAttribI4iv;
  PFNGLVERTEXATTRIBI1UIVPROC           glVertexAttribI1uiv;
  PFNGLVERTEXATTRIBI2UIVPROC           glVertexAttribI2uiv;
  PFNGLVERTEXATTRIBI3UIVPROC           glVertexAttribI3uiv;
  PFNGLVERTEXATTRIBI4UIVPROC           glVertexAttribI4uiv;
  PFNGLVERTEXATTRIBI4BVPROC            glVertexAttribI4bv;
  PFNGLVERTEXATTRIBI4SVPROC            glVertexAttribI4sv;
  PFNGLVERTEXATTRIBI4UBVPROC           glVertexAttribI4ubv;
  PFNGLVERTEXATTRIBI4USVPROC           glVertexAttribI4usv;
  PFNGLGETUNIFORMUIVPROC               glGetUniformuiv;
  PFNGLBINDFRAGDATALOCATIONPROC        glBindFragDataLocation;
  PFNGLGETFRAGDATALOCATIONPROC         glGetFragDataLocation;
  PFNGLUNIFORM1UIPROC                  glUniform1ui;
  PFNGLUNIFORM2UIPROC                  glUniform2ui;
  PFNGLUNIFORM3UIPROC                  glUniform3ui;
  PFNGLUNIFORM4UIPROC                  glUniform4ui;
  PFNGLUNIFORM1UIVPROC                 glUniform1uiv;
  PFNGLUNIFORM2UIVPROC                 glUniform2uiv;
  PFNGLUNIFORM3UIVPROC                 glUniform3uiv;
  PFNGLUNIFORM4UIVPROC                 glUniform4uiv;
  PFNGLTEXPARAMETERIIVPROC             glTexParameterIiv;
  PFNGLTEXPARAMETERIUIVPROC            glTexParameterIuiv;
  PFNGLGETTEXPARAMETERIIVPROC          glGetTexParameterIiv;
  PFNGLGETTEXPARAMETERIUIVPROC         glGetTexParameterIuiv;
  PFNGLCLEARBUFFERIVPROC               glClearBufferiv;
  PFNGLCLEARBUFFERUIVPROC              glClearBufferuiv;
  PFNGLCLEARBUFFERFVPROC               glClearBufferfv;
  PFNGLCLEARBUFFERFIPROC               glClearBufferfi;
  PFNGLGETSTRINGIPROC                  glGetStringi;

public: //! @name GL_ARB_uniform_buffer_object (added to OpenGL 3.1 core)

  PFNGLGETUNIFORMINDICESPROC           glGetUniformIndices;
  PFNGLGETACTIVEUNIFORMSIVPROC         glGetActiveUniformsiv;
  PFNGLGETACTIVEUNIFORMNAMEPROC        glGetActiveUniformName;
  PFNGLGETUNIFORMBLOCKINDEXPROC        glGetUniformBlockIndex;
  PFNGLGETACTIVEUNIFORMBLOCKIVPROC     glGetActiveUniformBlockiv;
  PFNGLGETACTIVEUNIFORMBLOCKNAMEPROC   glGetActiveUniformBlockName;
  PFNGLUNIFORMBLOCKBINDINGPROC         glUniformBlockBinding;

public: //! @name GL_ARB_copy_buffer (added to OpenGL 3.1 core)

  PFNGLCOPYBUFFERSUBDATAPROC           glCopyBufferSubData;

public: //! @name OpenGL 3.1

  PFNGLDRAWARRAYSINSTANCEDPROC         glDrawArraysInstanced;
  PFNGLDRAWELEMENTSINSTANCEDPROC       glDrawElementsInstanced;
  PFNGLTEXBUFFERPROC                   glTexBuffer;
  PFNGLPRIMITIVERESTARTINDEXPROC       glPrimitiveRestartIndex;

public: //! @name GL_ARB_draw_elements_base_vertex (added to OpenGL 3.2 core)

  PFNGLDRAWELEMENTSBASEVERTEXPROC      glDrawElementsBaseVertex;
  PFNGLDRAWRANGEELEMENTSBASEVERTEXPROC glDrawRangeElementsBaseVertex;
  PFNGLDRAWELEMENTSINSTANCEDBASEVERTEXPROC glDrawElementsInstancedBaseVertex;
  PFNGLMULTIDRAWELEMENTSBASEVERTEXPROC glMultiDrawElementsBaseVertex;

public: //! @name GL_ARB_provoking_vertex (added to OpenGL 3.2 core)

  PFNGLPROVOKINGVERTEXPROC             glProvokingVertex;

public: //! @name GL_ARB_sync (added to OpenGL 3.2 core)

  PFNGLFENCESYNCPROC                   glFenceSync;
  PFNGLISSYNCPROC                      glIsSync;
  PFNGLDELETESYNCPROC                  glDeleteSync;
  PFNGLCLIENTWAITSYNCPROC              glClientWaitSync;
  PFNGLWAITSYNCPROC                    glWaitSync;
  PFNGLGETINTEGER64VPROC               glGetInteger64v;
  PFNGLGETSYNCIVPROC                   glGetSynciv;

public: //! @name GL_ARB_texture_multisample (added to OpenGL 3.2 core)

  PFNGLTEXIMAGE2DMULTISAMPLEPROC       glTexImage2DMultisample;
  PFNGLTEXIMAGE3DMULTISAMPLEPROC       glTexImage3DMultisample;
  PFNGLGETMULTISAMPLEFVPROC            glGetMultisamplefv;
  PFNGLSAMPLEMASKIPROC                 glSampleMaski;

public: //! @name OpenGL 3.2

  PFNGLGETINTEGER64I_VPROC             glGetInteger64i_v;
  PFNGLGETBUFFERPARAMETERI64VPROC      glGetBufferParameteri64v;
  PFNGLFRAMEBUFFERTEXTUREPROC          glFramebufferTexture;

public: //! @name GL_ARB_blend_func_extended (added to OpenGL 3.3 core)

  PFNGLBINDFRAGDATALOCATIONINDEXEDPROC glBindFragDataLocationIndexed;
  PFNGLGETFRAGDATAINDEXPROC            glGetFragDataIndex;

public: //! @name GL_ARB_sampler_objects (added to OpenGL 3.3 core)

  PFNGLGENSAMPLERSPROC                 glGenSamplers;
  PFNGLDELETESAMPLERSPROC              glDeleteSamplers;
  PFNGLISSAMPLERPROC                   glIsSampler;
  PFNGLBINDSAMPLERPROC                 glBindSampler;
  PFNGLSAMPLERPARAMETERIPROC           glSamplerParameteri;
  PFNGLSAMPLERPARAMETERIVPROC          glSamplerParameteriv;
  PFNGLSAMPLERPARAMETERFPROC           glSamplerParameterf;
  PFNGLSAMPLERPARAMETERFVPROC          glSamplerParameterfv;
  PFNGLSAMPLERPARAMETERIIVPROC         glSamplerParameterIiv;
  PFNGLSAMPLERPARAMETERIUIVPROC        glSamplerParameterIuiv;
  PFNGLGETSAMPLERPARAMETERIVPROC       glGetSamplerParameteriv;
  PFNGLGETSAMPLERPARAMETERIIVPROC      glGetSamplerParameterIiv;
  PFNGLGETSAMPLERPARAMETERFVPROC       glGetSamplerParameterfv;
  PFNGLGETSAMPLERPARAMETERIUIVPROC     glGetSamplerParameterIuiv;

public: //! @name GL_ARB_timer_query (added to OpenGL 3.3 core)

  PFNGLQUERYCOUNTERPROC                glQueryCounter;
  PFNGLGETQUERYOBJECTI64VPROC          glGetQueryObjecti64v;
  PFNGLGETQUERYOBJECTUI64VPROC         glGetQueryObjectui64v;

public: //! @name GL_ARB_vertex_type_2_10_10_10_rev (added to OpenGL 3.3 core)

  PFNGLVERTEXATTRIBP1UIPROC            glVertexAttribP1ui;
  PFNGLVERTEXATTRIBP1UIVPROC           glVertexAttribP1uiv;
  PFNGLVERTEXATTRIBP2UIPROC            glVertexAttribP2ui;
  PFNGLVERTEXATTRIBP2UIVPROC           glVertexAttribP2uiv;
  PFNGLVERTEXATTRIBP3UIPROC            glVertexAttribP3ui;
  PFNGLVERTEXATTRIBP3UIVPROC           glVertexAttribP3uiv;
  PFNGLVERTEXATTRIBP4UIPROC            glVertexAttribP4ui;
  PFNGLVERTEXATTRIBP4UIVPROC           glVertexAttribP4uiv;

public: //! @name OpenGL 3.3

  PFNGLVERTEXATTRIBDIVISORPROC         glVertexAttribDivisor;

public: //! @name GL_ARB_draw_indirect (added to OpenGL 4.0 core)

  PFNGLDRAWARRAYSINDIRECTPROC          glDrawArraysIndirect;
  PFNGLDRAWELEMENTSINDIRECTPROC        glDrawElementsIndirect;

public: //! @name GL_ARB_gpu_shader_fp64 (added to OpenGL 4.0 core)

  PFNGLUNIFORM1DPROC                   glUniform1d;
  PFNGLUNIFORM2DPROC                   glUniform2d;
  PFNGLUNIFORM3DPROC                   glUniform3d;
  PFNGLUNIFORM4DPROC                   glUniform4d;
  PFNGLUNIFORM1DVPROC                  glUniform1dv;
  PFNGLUNIFORM2DVPROC                  glUniform2dv;
  PFNGLUNIFORM3DVPROC                  glUniform3dv;
  PFNGLUNIFORM4DVPROC                  glUniform4dv;
  PFNGLUNIFORMMATRIX2DVPROC            glUniformMatrix2dv;
  PFNGLUNIFORMMATRIX3DVPROC            glUniformMatrix3dv;
  PFNGLUNIFORMMATRIX4DVPROC            glUniformMatrix4dv;
  PFNGLUNIFORMMATRIX2X3DVPROC          glUniformMatrix2x3dv;
  PFNGLUNIFORMMATRIX2X4DVPROC          glUniformMatrix2x4dv;
  PFNGLUNIFORMMATRIX3X2DVPROC          glUniformMatrix3x2dv;
  PFNGLUNIFORMMATRIX3X4DVPROC          glUniformMatrix3x4dv;
  PFNGLUNIFORMMATRIX4X2DVPROC          glUniformMatrix4x2dv;
  PFNGLUNIFORMMATRIX4X3DVPROC          glUniformMatrix4x3dv;
  PFNGLGETUNIFORMDVPROC                glGetUniformdv;

public: //! @name GL_ARB_shader_subroutine (added to OpenGL 4.0 core)

  PFNGLGETSUBROUTINEUNIFORMLOCATIONPROC   glGetSubroutineUniformLocation;
  PFNGLGETSUBROUTINEINDEXPROC             glGetSubroutineIndex;
  PFNGLGETACTIVESUBROUTINEUNIFORMIVPROC   glGetActiveSubroutineUniformiv;
  PFNGLGETACTIVESUBROUTINEUNIFORMNAMEPROC glGetActiveSubroutineUniformName;
  PFNGLGETACTIVESUBROUTINENAMEPROC        glGetActiveSubroutineName;
  PFNGLUNIFORMSUBROUTINESUIVPROC          glUniformSubroutinesuiv;
  PFNGLGETUNIFORMSUBROUTINEUIVPROC        glGetUniformSubroutineuiv;
  PFNGLGETPROGRAMSTAGEIVPROC              glGetProgramStageiv;

public: //! @name GL_ARB_tessellation_shader (added to OpenGL 4.0 core)

  PFNGLPATCHPARAMETERIPROC             glPatchParameteri;
  PFNGLPATCHPARAMETERFVPROC            glPatchParameterfv;

public: //! @name GL_ARB_transform_feedback2 (added to OpenGL 4.0 core)

  PFNGLBINDTRANSFORMFEEDBACKPROC       glBindTransformFeedback;
  PFNGLDELETETRANSFORMFEEDBACKSPROC    glDeleteTransformFeedbacks;
  PFNGLGENTRANSFORMFEEDBACKSPROC       glGenTransformFeedbacks;
  PFNGLISTRANSFORMFEEDBACKPROC         glIsTransformFeedback;
  PFNGLPAUSETRANSFORMFEEDBACKPROC      glPauseTransformFeedback;
  PFNGLRESUMETRANSFORMFEEDBACKPROC     glResumeTransformFeedback;
  PFNGLDRAWTRANSFORMFEEDBACKPROC       glDrawTransformFeedback;

public: //! @name GL_ARB_transform_feedback3 (added to OpenGL 4.0 core)

  PFNGLDRAWTRANSFORMFEEDBACKSTREAMPROC glDrawTransformFeedbackStream;
  PFNGLBEGINQUERYINDEXEDPROC           glBeginQueryIndexed;
  PFNGLENDQUERYINDEXEDPROC             glEndQueryIndexed;
  PFNGLGETQUERYINDEXEDIVPROC           glGetQueryIndexediv;

public: //! @name OpenGL 4.0

  PFNGLMINSAMPLESHADINGPROC            glMinSampleShading;
  PFNGLBLENDEQUATIONIPROC              glBlendEquationi;
  PFNGLBLENDEQUATIONSEPARATEIPROC      glBlendEquationSeparatei;
  PFNGLBLENDFUNCIPROC                  glBlendFunci;
  PFNGLBLENDFUNCSEPARATEIPROC          glBlendFuncSeparatei;

public: //! @name GL_ARB_ES2_compatibility (added to OpenGL 4.1 core)

  PFNGLRELEASESHADERCOMPILERPROC       glReleaseShaderCompiler;
  PFNGLSHADERBINARYPROC                glShaderBinary;
  PFNGLGETSHADERPRECISIONFORMATPROC    glGetShaderPrecisionFormat;
  PFNGLDEPTHRANGEFPROC                 glDepthRangef;
  PFNGLCLEARDEPTHFPROC                 glClearDepthf;

public: //! @name GL_ARB_get_program_binary (added to OpenGL 4.1 core)

  PFNGLGETPROGRAMBINARYPROC            glGetProgramBinary;
  PFNGLPROGRAMBINARYPROC               glProgramBinary;
  PFNGLPROGRAMPARAMETERIPROC           glProgramParameteri;

public: //! @name GL_ARB_separate_shader_objects (added to OpenGL 4.1 core)

  PFNGLUSEPROGRAMSTAGESPROC            glUseProgramStages;
  PFNGLACTIVESHADERPROGRAMPROC         glActiveShaderProgram;
  PFNGLCREATESHADERPROGRAMVPROC        glCreateShaderProgramv;
  PFNGLBINDPROGRAMPIPELINEPROC         glBindProgramPipeline;
  PFNGLDELETEPROGRAMPIPELINESPROC      glDeleteProgramPipelines;
  PFNGLGENPROGRAMPIPELINESPROC         glGenProgramPipelines;
  PFNGLISPROGRAMPIPELINEPROC           glIsProgramPipeline;
  PFNGLGETPROGRAMPIPELINEIVPROC        glGetProgramPipelineiv;
  PFNGLPROGRAMUNIFORM1IPROC            glProgramUniform1i;
  PFNGLPROGRAMUNIFORM1IVPROC           glProgramUniform1iv;
  PFNGLPROGRAMUNIFORM1FPROC            glProgramUniform1f;
  PFNGLPROGRAMUNIFORM1FVPROC           glProgramUniform1fv;
  PFNGLPROGRAMUNIFORM1DPROC            glProgramUniform1d;
  PFNGLPROGRAMUNIFORM1DVPROC           glProgramUniform1dv;
  PFNGLPROGRAMUNIFORM1UIPROC           glProgramUniform1ui;
  PFNGLPROGRAMUNIFORM1UIVPROC          glProgramUniform1uiv;
  PFNGLPROGRAMUNIFORM2IPROC            glProgramUniform2i;
  PFNGLPROGRAMUNIFORM2IVPROC           glProgramUniform2iv;
  PFNGLPROGRAMUNIFORM2FPROC            glProgramUniform2f;
  PFNGLPROGRAMUNIFORM2FVPROC           glProgramUniform2fv;
  PFNGLPROGRAMUNIFORM2DPROC            glProgramUniform2d;
  PFNGLPROGRAMUNIFORM2DVPROC           glProgramUniform2dv;
  PFNGLPROGRAMUNIFORM2UIPROC           glProgramUniform2ui;
  PFNGLPROGRAMUNIFORM2UIVPROC          glProgramUniform2uiv;
  PFNGLPROGRAMUNIFORM3IPROC            glProgramUniform3i;
  PFNGLPROGRAMUNIFORM3IVPROC           glProgramUniform3iv;
  PFNGLPROGRAMUNIFORM3FPROC            glProgramUniform3f;
  PFNGLPROGRAMUNIFORM3FVPROC           glProgramUniform3fv;
  PFNGLPROGRAMUNIFORM3DPROC            glProgramUniform3d;
  PFNGLPROGRAMUNIFORM3DVPROC           glProgramUniform3dv;
  PFNGLPROGRAMUNIFORM3UIPROC           glProgramUniform3ui;
  PFNGLPROGRAMUNIFORM3UIVPROC          glProgramUniform3uiv;
  PFNGLPROGRAMUNIFORM4IPROC            glProgramUniform4i;
  PFNGLPROGRAMUNIFORM4IVPROC           glProgramUniform4iv;
  PFNGLPROGRAMUNIFORM4FPROC            glProgramUniform4f;
  PFNGLPROGRAMUNIFORM4FVPROC           glProgramUniform4fv;
  PFNGLPROGRAMUNIFORM4DPROC            glProgramUniform4d;
  PFNGLPROGRAMUNIFORM4DVPROC           glProgramUniform4dv;
  PFNGLPROGRAMUNIFORM4UIPROC           glProgramUniform4ui;
  PFNGLPROGRAMUNIFORM4UIVPROC          glProgramUniform4uiv;
  PFNGLPROGRAMUNIFORMMATRIX2FVPROC     glProgramUniformMatrix2fv;
  PFNGLPROGRAMUNIFORMMATRIX3FVPROC     glProgramUniformMatrix3fv;
  PFNGLPROGRAMUNIFORMMATRIX4FVPROC     glProgramUniformMatrix4fv;
  PFNGLPROGRAMUNIFORMMATRIX2DVPROC     glProgramUniformMatrix2dv;
  PFNGLPROGRAMUNIFORMMATRIX3DVPROC     glProgramUniformMatrix3dv;
  PFNGLPROGRAMUNIFORMMATRIX4DVPROC     glProgramUniformMatrix4dv;
  PFNGLPROGRAMUNIFORMMATRIX2X3FVPROC   glProgramUniformMatrix2x3fv;
  PFNGLPROGRAMUNIFORMMATRIX3X2FVPROC   glProgramUniformMatrix3x2fv;
  PFNGLPROGRAMUNIFORMMATRIX2X4FVPROC   glProgramUniformMatrix2x4fv;
  PFNGLPROGRAMUNIFORMMATRIX4X2FVPROC   glProgramUniformMatrix4x2fv;
  PFNGLPROGRAMUNIFORMMATRIX3X4FVPROC   glProgramUniformMatrix3x4fv;
  PFNGLPROGRAMUNIFORMMATRIX4X3FVPROC   glProgramUniformMatrix4x3fv;
  PFNGLPROGRAMUNIFORMMATRIX2X3DVPROC   glProgramUniformMatrix2x3dv;
  PFNGLPROGRAMUNIFORMMATRIX3X2DVPROC   glProgramUniformMatrix3x2dv;
  PFNGLPROGRAMUNIFORMMATRIX2X4DVPROC   glProgramUniformMatrix2x4dv;
  PFNGLPROGRAMUNIFORMMATRIX4X2DVPROC   glProgramUniformMatrix4x2dv;
  PFNGLPROGRAMUNIFORMMATRIX3X4DVPROC   glProgramUniformMatrix3x4dv;
  PFNGLPROGRAMUNIFORMMATRIX4X3DVPROC   glProgramUniformMatrix4x3dv;
  PFNGLVALIDATEPROGRAMPIPELINEPROC     glValidateProgramPipeline;
  PFNGLGETPROGRAMPIPELINEINFOLOGPROC   glGetProgramPipelineInfoLog;

public: //! @name GL_ARB_vertex_attrib_64bit (added to OpenGL 4.1 core)

  PFNGLVERTEXATTRIBL1DPROC             glVertexAttribL1d;
  PFNGLVERTEXATTRIBL2DPROC             glVertexAttribL2d;
  PFNGLVERTEXATTRIBL3DPROC             glVertexAttribL3d;
  PFNGLVERTEXATTRIBL4DPROC             glVertexAttribL4d;
  PFNGLVERTEXATTRIBL1DVPROC            glVertexAttribL1dv;
  PFNGLVERTEXATTRIBL2DVPROC            glVertexAttribL2dv;
  PFNGLVERTEXATTRIBL3DVPROC            glVertexAttribL3dv;
  PFNGLVERTEXATTRIBL4DVPROC            glVertexAttribL4dv;
  PFNGLVERTEXATTRIBLPOINTERPROC        glVertexAttribLPointer;
  PFNGLGETVERTEXATTRIBLDVPROC          glGetVertexAttribLdv;

public: //! @name GL_ARB_viewport_array (added to OpenGL 4.1 core)

  PFNGLVIEWPORTARRAYVPROC              glViewportArrayv;
  PFNGLVIEWPORTINDEXEDFPROC            glViewportIndexedf;
  PFNGLVIEWPORTINDEXEDFVPROC           glViewportIndexedfv;
  PFNGLSCISSORARRAYVPROC               glScissorArrayv;
  PFNGLSCISSORINDEXEDPROC              glScissorIndexed;
  PFNGLSCISSORINDEXEDVPROC             glScissorIndexedv;
  PFNGLDEPTHRANGEARRAYVPROC            glDepthRangeArrayv;
  PFNGLDEPTHRANGEINDEXEDPROC           glDepthRangeIndexed;
  PFNGLGETFLOATI_VPROC                 glGetFloati_v;
  PFNGLGETDOUBLEI_VPROC                glGetDoublei_v;

public: //! @name OpenGL 4.1

  //

public: //! @name GL_ARB_base_instance (added to OpenGL 4.2 core)

  PFNGLDRAWARRAYSINSTANCEDBASEINSTANCEPROC             glDrawArraysInstancedBaseInstance;
  PFNGLDRAWELEMENTSINSTANCEDBASEINSTANCEPROC           glDrawElementsInstancedBaseInstance;
  PFNGLDRAWELEMENTSINSTANCEDBASEVERTEXBASEINSTANCEPROC glDrawElementsInstancedBaseVertexBaseInstance;

public: //! @name GL_ARB_transform_feedback_instanced (added to OpenGL 4.2 core)

  PFNGLDRAWTRANSFORMFEEDBACKINSTANCEDPROC              glDrawTransformFeedbackInstanced;
  PFNGLDRAWTRANSFORMFEEDBACKSTREAMINSTANCEDPROC        glDrawTransformFeedbackStreamInstanced;

public: //! @name GL_ARB_internalformat_query (added to OpenGL 4.2 core)

  PFNGLGETINTERNALFORMATIVPROC                         glGetInternalformativ;

public: //! @name GL_ARB_shader_atomic_counters (added to OpenGL 4.2 core)

  PFNGLGETACTIVEATOMICCOUNTERBUFFERIVPROC              glGetActiveAtomicCounterBufferiv;

public: //! @name GL_ARB_shader_image_load_store (added to OpenGL 4.2 core)

  PFNGLBINDIMAGETEXTUREPROC                            glBindImageTexture;
  PFNGLMEMORYBARRIERPROC                               glMemoryBarrier;

public: //! @name GL_ARB_texture_storage (added to OpenGL 4.2 core)

  PFNGLTEXSTORAGE1DPROC                                glTexStorage1D;
  PFNGLTEXSTORAGE2DPROC                                glTexStorage2D;
  PFNGLTEXSTORAGE3DPROC                                glTexStorage3D;

public: //! @name OpenGL 4.2

public: //! @name OpenGL 4.3

  PFNGLCLEARBUFFERDATAPROC                 glClearBufferData;
  PFNGLCLEARBUFFERSUBDATAPROC              glClearBufferSubData;
  PFNGLDISPATCHCOMPUTEPROC                 glDispatchCompute;
  PFNGLDISPATCHCOMPUTEINDIRECTPROC         glDispatchComputeIndirect;
  PFNGLCOPYIMAGESUBDATAPROC                glCopyImageSubData;
  PFNGLFRAMEBUFFERPARAMETERIPROC           glFramebufferParameteri;
  PFNGLGETFRAMEBUFFERPARAMETERIVPROC       glGetFramebufferParameteriv;
  PFNGLGETINTERNALFORMATI64VPROC           glGetInternalformati64v;
  PFNGLINVALIDATETEXSUBIMAGEPROC           glInvalidateTexSubImage;
  PFNGLINVALIDATETEXIMAGEPROC              glInvalidateTexImage;
  PFNGLINVALIDATEBUFFERSUBDATAPROC         glInvalidateBufferSubData;
  PFNGLINVALIDATEBUFFERDATAPROC            glInvalidateBufferData;
  PFNGLINVALIDATEFRAMEBUFFERPROC           glInvalidateFramebuffer;
  PFNGLINVALIDATESUBFRAMEBUFFERPROC        glInvalidateSubFramebuffer;
  PFNGLMULTIDRAWARRAYSINDIRECTPROC         glMultiDrawArraysIndirect;
  PFNGLMULTIDRAWELEMENTSINDIRECTPROC       glMultiDrawElementsIndirect;
  PFNGLGETPROGRAMINTERFACEIVPROC           glGetProgramInterfaceiv;
  PFNGLGETPROGRAMRESOURCEINDEXPROC         glGetProgramResourceIndex;
  PFNGLGETPROGRAMRESOURCENAMEPROC          glGetProgramResourceName;
  PFNGLGETPROGRAMRESOURCEIVPROC            glGetProgramResourceiv;
  PFNGLGETPROGRAMRESOURCELOCATIONPROC      glGetProgramResourceLocation;
  PFNGLGETPROGRAMRESOURCELOCATIONINDEXPROC glGetProgramResourceLocationIndex;
  PFNGLSHADERSTORAGEBLOCKBINDINGPROC       glShaderStorageBlockBinding;
  PFNGLTEXBUFFERRANGEPROC                  glTexBufferRange;
  PFNGLTEXSTORAGE2DMULTISAMPLEPROC         glTexStorage2DMultisample;
  PFNGLTEXSTORAGE3DMULTISAMPLEPROC         glTexStorage3DMultisample;
  PFNGLTEXTUREVIEWPROC                     glTextureView;
  PFNGLBINDVERTEXBUFFERPROC                glBindVertexBuffer;
  PFNGLVERTEXATTRIBFORMATPROC              glVertexAttribFormat;
  PFNGLVERTEXATTRIBIFORMATPROC             glVertexAttribIFormat;
  PFNGLVERTEXATTRIBLFORMATPROC             glVertexAttribLFormat;
  PFNGLVERTEXATTRIBBINDINGPROC             glVertexAttribBinding;
  PFNGLVERTEXBINDINGDIVISORPROC            glVertexBindingDivisor;
  PFNGLDEBUGMESSAGECONTROLPROC             glDebugMessageControl;
  PFNGLDEBUGMESSAGEINSERTPROC              glDebugMessageInsert;
  PFNGLDEBUGMESSAGECALLBACKPROC            glDebugMessageCallback;
  PFNGLGETDEBUGMESSAGELOGPROC              glGetDebugMessageLog;
  PFNGLPUSHDEBUGGROUPPROC                  glPushDebugGroup;
  PFNGLPOPDEBUGGROUPPROC                   glPopDebugGroup;
  PFNGLOBJECTLABELPROC                     glObjectLabel;
  PFNGLGETOBJECTLABELPROC                  glGetObjectLabel;
  PFNGLOBJECTPTRLABELPROC                  glObjectPtrLabel;
  PFNGLGETOBJECTPTRLABELPROC               glGetObjectPtrLabel;

public: //! @name OpenGL 4.4

  PFNGLBUFFERSTORAGEPROC     glBufferStorage;
  PFNGLCLEARTEXIMAGEPROC     glClearTexImage;
  PFNGLCLEARTEXSUBIMAGEPROC  glClearTexSubImage;
  PFNGLBINDBUFFERSBASEPROC   glBindBuffersBase;
  PFNGLBINDBUFFERSRANGEPROC  glBindBuffersRange;
  PFNGLBINDTEXTURESPROC      glBindTextures;
  PFNGLBINDSAMPLERSPROC      glBindSamplers;
  PFNGLBINDIMAGETEXTURESPROC glBindImageTextures;
  PFNGLBINDVERTEXBUFFERSPROC glBindVertexBuffers;

public: //! @name OpenGL 4.5

  PFNGLCLIPCONTROLPROC glClipControl;
  PFNGLCREATETRANSFORMFEEDBACKSPROC glCreateTransformFeedbacks;
  PFNGLTRANSFORMFEEDBACKBUFFERBASEPROC glTransformFeedbackBufferBase;
  PFNGLTRANSFORMFEEDBACKBUFFERRANGEPROC glTransformFeedbackBufferRange;
  PFNGLGETTRANSFORMFEEDBACKIVPROC glGetTransformFeedbackiv;
  PFNGLGETTRANSFORMFEEDBACKI_VPROC glGetTransformFeedbacki_v;
  PFNGLGETTRANSFORMFEEDBACKI64_VPROC glGetTransformFeedbacki64_v;
  PFNGLCREATEBUFFERSPROC glCreateBuffers;
  PFNGLNAMEDBUFFERSTORAGEPROC glNamedBufferStorage;
  PFNGLNAMEDBUFFERDATAPROC glNamedBufferData;
  PFNGLNAMEDBUFFERSUBDATAPROC glNamedBufferSubData;
  PFNGLCOPYNAMEDBUFFERSUBDATAPROC glCopyNamedBufferSubData;
  PFNGLCLEARNAMEDBUFFERDATAPROC glClearNamedBufferData;
  PFNGLCLEARNAMEDBUFFERSUBDATAPROC glClearNamedBufferSubData;
  PFNGLMAPNAMEDBUFFERPROC glMapNamedBuffer;
  PFNGLMAPNAMEDBUFFERRANGEPROC glMapNamedBufferRange;
  PFNGLUNMAPNAMEDBUFFERPROC glUnmapNamedBuffer;
  PFNGLFLUSHMAPPEDNAMEDBUFFERRANGEPROC glFlushMappedNamedBufferRange;
  PFNGLGETNAMEDBUFFERPARAMETERIVPROC glGetNamedBufferParameteriv;
  PFNGLGETNAMEDBUFFERPARAMETERI64VPROC glGetNamedBufferParameteri64v;
  PFNGLGETNAMEDBUFFERPOINTERVPROC glGetNamedBufferPointerv;
  PFNGLGETNAMEDBUFFERSUBDATAPROC glGetNamedBufferSubData;
  PFNGLCREATEFRAMEBUFFERSPROC glCreateFramebuffers;
  PFNGLNAMEDFRAMEBUFFERRENDERBUFFERPROC glNamedFramebufferRenderbuffer;
  PFNGLNAMEDFRAMEBUFFERPARAMETERIPROC glNamedFramebufferParameteri;
  PFNGLNAMEDFRAMEBUFFERTEXTUREPROC glNamedFramebufferTexture;
  PFNGLNAMEDFRAMEBUFFERTEXTURELAYERPROC glNamedFramebufferTextureLayer;
  PFNGLNAMEDFRAMEBUFFERDRAWBUFFERPROC glNamedFramebufferDrawBuffer;
  PFNGLNAMEDFRAMEBUFFERDRAWBUFFERSPROC glNamedFramebufferDrawBuffers;
  PFNGLNAMEDFRAMEBUFFERREADBUFFERPROC glNamedFramebufferReadBuffer;
  PFNGLINVALIDATENAMEDFRAMEBUFFERDATAPROC glInvalidateNamedFramebufferData;
  PFNGLINVALIDATENAMEDFRAMEBUFFERSUBDATAPROC glInvalidateNamedFramebufferSubData;
  PFNGLCLEARNAMEDFRAMEBUFFERIVPROC glClearNamedFramebufferiv;
  PFNGLCLEARNAMEDFRAMEBUFFERUIVPROC glClearNamedFramebufferuiv;
  PFNGLCLEARNAMEDFRAMEBUFFERFVPROC glClearNamedFramebufferfv;
  PFNGLCLEARNAMEDFRAMEBUFFERFIPROC glClearNamedFramebufferfi;
  PFNGLBLITNAMEDFRAMEBUFFERPROC glBlitNamedFramebuffer;
  PFNGLCHECKNAMEDFRAMEBUFFERSTATUSPROC glCheckNamedFramebufferStatus;
  PFNGLGETNAMEDFRAMEBUFFERPARAMETERIVPROC glGetNamedFramebufferParameteriv;
  PFNGLGETNAMEDFRAMEBUFFERATTACHMENTPARAMETERIVPROC glGetNamedFramebufferAttachmentParameteriv;
  PFNGLCREATERENDERBUFFERSPROC glCreateRenderbuffers;
  PFNGLNAMEDRENDERBUFFERSTORAGEPROC glNamedRenderbufferStorage;
  PFNGLNAMEDRENDERBUFFERSTORAGEMULTISAMPLEPROC glNamedRenderbufferStorageMultisample;
  PFNGLGETNAMEDRENDERBUFFERPARAMETERIVPROC glGetNamedRenderbufferParameteriv;
  PFNGLCREATETEXTURESPROC glCreateTextures;
  PFNGLTEXTUREBUFFERPROC glTextureBuffer;
  PFNGLTEXTUREBUFFERRANGEPROC glTextureBufferRange;
  PFNGLTEXTURESTORAGE1DPROC glTextureStorage1D;
  PFNGLTEXTURESTORAGE2DPROC glTextureStorage2D;
  PFNGLTEXTURESTORAGE3DPROC glTextureStorage3D;
  PFNGLTEXTURESTORAGE2DMULTISAMPLEPROC glTextureStorage2DMultisample;
  PFNGLTEXTURESTORAGE3DMULTISAMPLEPROC glTextureStorage3DMultisample;
  PFNGLTEXTURESUBIMAGE1DPROC glTextureSubImage1D;
  PFNGLTEXTURESUBIMAGE2DPROC glTextureSubImage2D;
  PFNGLTEXTURESUBIMAGE3DPROC glTextureSubImage3D;
  PFNGLCOMPRESSEDTEXTURESUBIMAGE1DPROC glCompressedTextureSubImage1D;
  PFNGLCOMPRESSEDTEXTURESUBIMAGE2DPROC glCompressedTextureSubImage2D;
  PFNGLCOMPRESSEDTEXTURESUBIMAGE3DPROC glCompressedTextureSubImage3D;
  PFNGLCOPYTEXTURESUBIMAGE1DPROC glCopyTextureSubImage1D;
  PFNGLCOPYTEXTURESUBIMAGE2DPROC glCopyTextureSubImage2D;
  PFNGLCOPYTEXTURESUBIMAGE3DPROC glCopyTextureSubImage3D;
  PFNGLTEXTUREPARAMETERFPROC glTextureParameterf;
  PFNGLTEXTUREPARAMETERFVPROC glTextureParameterfv;
  PFNGLTEXTUREPARAMETERIPROC glTextureParameteri;
  PFNGLTEXTUREPARAMETERIIVPROC glTextureParameterIiv;
  PFNGLTEXTUREPARAMETERIUIVPROC glTextureParameterIuiv;
  PFNGLTEXTUREPARAMETERIVPROC glTextureParameteriv;
  PFNGLGENERATETEXTUREMIPMAPPROC glGenerateTextureMipmap;
  PFNGLBINDTEXTUREUNITPROC glBindTextureUnit;
  PFNGLGETTEXTUREIMAGEPROC glGetTextureImage;
  PFNGLGETCOMPRESSEDTEXTUREIMAGEPROC glGetCompressedTextureImage;
  PFNGLGETTEXTURELEVELPARAMETERFVPROC glGetTextureLevelParameterfv;
  PFNGLGETTEXTURELEVELPARAMETERIVPROC glGetTextureLevelParameteriv;
  PFNGLGETTEXTUREPARAMETERFVPROC glGetTextureParameterfv;
  PFNGLGETTEXTUREPARAMETERIIVPROC glGetTextureParameterIiv;
  PFNGLGETTEXTUREPARAMETERIUIVPROC glGetTextureParameterIuiv;
  PFNGLGETTEXTUREPARAMETERIVPROC glGetTextureParameteriv;
  PFNGLCREATEVERTEXARRAYSPROC glCreateVertexArrays;
  PFNGLDISABLEVERTEXARRAYATTRIBPROC glDisableVertexArrayAttrib;
  PFNGLENABLEVERTEXARRAYATTRIBPROC glEnableVertexArrayAttrib;
  PFNGLVERTEXARRAYELEMENTBUFFERPROC glVertexArrayElementBuffer;
  PFNGLVERTEXARRAYVERTEXBUFFERPROC glVertexArrayVertexBuffer;
  PFNGLVERTEXARRAYVERTEXBUFFERSPROC glVertexArrayVertexBuffers;
  PFNGLVERTEXARRAYATTRIBBINDINGPROC glVertexArrayAttribBinding;
  PFNGLVERTEXARRAYATTRIBFORMATPROC glVertexArrayAttribFormat;
  PFNGLVERTEXARRAYATTRIBIFORMATPROC glVertexArrayAttribIFormat;
  PFNGLVERTEXARRAYATTRIBLFORMATPROC glVertexArrayAttribLFormat;
  PFNGLVERTEXARRAYBINDINGDIVISORPROC glVertexArrayBindingDivisor;
  PFNGLGETVERTEXARRAYIVPROC glGetVertexArrayiv;
  PFNGLGETVERTEXARRAYINDEXEDIVPROC glGetVertexArrayIndexediv;
  PFNGLGETVERTEXARRAYINDEXED64IVPROC glGetVertexArrayIndexed64iv;
  PFNGLCREATESAMPLERSPROC glCreateSamplers;
  PFNGLCREATEPROGRAMPIPELINESPROC glCreateProgramPipelines;
  PFNGLCREATEQUERIESPROC glCreateQueries;
  PFNGLGETQUERYBUFFEROBJECTI64VPROC glGetQueryBufferObjecti64v;
  PFNGLGETQUERYBUFFEROBJECTIVPROC glGetQueryBufferObjectiv;
  PFNGLGETQUERYBUFFEROBJECTUI64VPROC glGetQueryBufferObjectui64v;
  PFNGLGETQUERYBUFFEROBJECTUIVPROC glGetQueryBufferObjectuiv;
  PFNGLMEMORYBARRIERBYREGIONPROC glMemoryBarrierByRegion;
  PFNGLGETTEXTURESUBIMAGEPROC glGetTextureSubImage;
  PFNGLGETCOMPRESSEDTEXTURESUBIMAGEPROC glGetCompressedTextureSubImage;
  PFNGLGETGRAPHICSRESETSTATUSPROC glGetGraphicsResetStatus;
  PFNGLGETNCOMPRESSEDTEXIMAGEPROC glGetnCompressedTexImage;
  PFNGLGETNTEXIMAGEPROC glGetnTexImage;
  PFNGLGETNUNIFORMDVPROC glGetnUniformdv;
  PFNGLGETNUNIFORMFVPROC glGetnUniformfv;
  PFNGLGETNUNIFORMIVPROC glGetnUniformiv;
  PFNGLGETNUNIFORMUIVPROC glGetnUniformuiv;
  PFNGLREADNPIXELSPROC glReadnPixels;
  PFNGLTEXTUREBARRIERPROC glTextureBarrier;

public: //! @name OpenGL 4.6

  PFNGLSPECIALIZESHADERPROC glSpecializeShader;
  PFNGLMULTIDRAWARRAYSINDIRECTCOUNTPROC glMultiDrawArraysIndirectCount;
  PFNGLMULTIDRAWELEMENTSINDIRECTCOUNTPROC glMultiDrawElementsIndirectCount;
  PFNGLPOLYGONOFFSETCLAMPPROC glPolygonOffsetClamp;

public: //! @name GL_EXT_geometry_shader4

  PFNGLPROGRAMPARAMETERIEXTPROC glProgramParameteriEXT;

public: //! @name GL_ARB_bindless_texture

  PFNGLGETTEXTUREHANDLEARBPROC             glGetTextureHandleARB;
  PFNGLGETTEXTURESAMPLERHANDLEARBPROC      glGetTextureSamplerHandleARB;
  PFNGLMAKETEXTUREHANDLERESIDENTARBPROC    glMakeTextureHandleResidentARB;
  PFNGLMAKETEXTUREHANDLENONRESIDENTARBPROC glMakeTextureHandleNonResidentARB;
  PFNGLGETIMAGEHANDLEARBPROC               glGetImageHandleARB;
  PFNGLMAKEIMAGEHANDLERESIDENTARBPROC      glMakeImageHandleResidentARB;
  PFNGLMAKEIMAGEHANDLENONRESIDENTARBPROC   glMakeImageHandleNonResidentARB;
  PFNGLUNIFORMHANDLEUI64ARBPROC            glUniformHandleui64ARB;
  PFNGLUNIFORMHANDLEUI64VARBPROC           glUniformHandleui64vARB;
  PFNGLPROGRAMUNIFORMHANDLEUI64ARBPROC     glProgramUniformHandleui64ARB;
  PFNGLPROGRAMUNIFORMHANDLEUI64VARBPROC    glProgramUniformHandleui64vARB;
  PFNGLISTEXTUREHANDLERESIDENTARBPROC      glIsTextureHandleResidentARB;
  PFNGLISIMAGEHANDLERESIDENTARBPROC        glIsImageHandleResidentARB;
  PFNGLVERTEXATTRIBL1UI64ARBPROC           glVertexAttribL1ui64ARB;
  PFNGLVERTEXATTRIBL1UI64VARBPROC          glVertexAttribL1ui64vARB;
  PFNGLGETVERTEXATTRIBLUI64VARBPROC        glGetVertexAttribLui64vARB;

#if defined(_WIN32)
public: //! @name wgl extensions

  typedef const char* (WINAPI *wglGetExtensionsStringARB_t)(HDC theDeviceContext);
  wglGetExtensionsStringARB_t wglGetExtensionsStringARB;

  typedef BOOL        (WINAPI *wglSwapIntervalEXT_t)(int theInterval);
  wglSwapIntervalEXT_t wglSwapIntervalEXT;

  // WGL_ARB_pixel_format

#ifndef WGL_NUMBER_PIXEL_FORMATS_ARB
  #define WGL_NUMBER_PIXEL_FORMATS_ARB            0x2000
  #define WGL_DRAW_TO_WINDOW_ARB                  0x2001
  #define WGL_DRAW_TO_BITMAP_ARB                  0x2002
  #define WGL_ACCELERATION_ARB                    0x2003
  #define WGL_NEED_PALETTE_ARB                    0x2004
  #define WGL_NEED_SYSTEM_PALETTE_ARB             0x2005
  #define WGL_SWAP_LAYER_BUFFERS_ARB              0x2006
  #define WGL_SWAP_METHOD_ARB                     0x2007
  #define WGL_NUMBER_OVERLAYS_ARB                 0x2008
  #define WGL_NUMBER_UNDERLAYS_ARB                0x2009
  #define WGL_TRANSPARENT_ARB                     0x200A
  #define WGL_TRANSPARENT_RED_VALUE_ARB           0x2037
  #define WGL_TRANSPARENT_GREEN_VALUE_ARB         0x2038
  #define WGL_TRANSPARENT_BLUE_VALUE_ARB          0x2039
  #define WGL_TRANSPARENT_ALPHA_VALUE_ARB         0x203A
  #define WGL_TRANSPARENT_INDEX_VALUE_ARB         0x203B
  #define WGL_SHARE_DEPTH_ARB                     0x200C
  #define WGL_SHARE_STENCIL_ARB                   0x200D
  #define WGL_SHARE_ACCUM_ARB                     0x200E
  #define WGL_SUPPORT_GDI_ARB                     0x200F
  #define WGL_SUPPORT_OPENGL_ARB                  0x2010
  #define WGL_DOUBLE_BUFFER_ARB                   0x2011
  #define WGL_STEREO_ARB                          0x2012
  #define WGL_PIXEL_TYPE_ARB                      0x2013
  #define WGL_COLOR_BITS_ARB                      0x2014
  #define WGL_RED_BITS_ARB                        0x2015
  #define WGL_RED_SHIFT_ARB                       0x2016
  #define WGL_GREEN_BITS_ARB                      0x2017
  #define WGL_GREEN_SHIFT_ARB                     0x2018
  #define WGL_BLUE_BITS_ARB                       0x2019
  #define WGL_BLUE_SHIFT_ARB                      0x201A
  #define WGL_ALPHA_BITS_ARB                      0x201B
  #define WGL_ALPHA_SHIFT_ARB                     0x201C
  #define WGL_ACCUM_BITS_ARB                      0x201D
  #define WGL_ACCUM_RED_BITS_ARB                  0x201E
  #define WGL_ACCUM_GREEN_BITS_ARB                0x201F
  #define WGL_ACCUM_BLUE_BITS_ARB                 0x2020
  #define WGL_ACCUM_ALPHA_BITS_ARB                0x2021
  #define WGL_DEPTH_BITS_ARB                      0x2022
  #define WGL_STENCIL_BITS_ARB                    0x2023
  #define WGL_AUX_BUFFERS_ARB                     0x2024

  #define WGL_NO_ACCELERATION_ARB                 0x2025
  #define WGL_GENERIC_ACCELERATION_ARB            0x2026
  #define WGL_FULL_ACCELERATION_ARB               0x2027

  #define WGL_SWAP_EXCHANGE_ARB                   0x2028
  #define WGL_SWAP_COPY_ARB                       0x2029
  #define WGL_SWAP_UNDEFINED_ARB                  0x202A

  #define WGL_TYPE_RGBA_ARB                       0x202B
  #define WGL_TYPE_COLORINDEX_ARB                 0x202C

#endif // WGL_NUMBER_PIXEL_FORMATS_ARB

      // WGL_ARB_multisample
#ifndef WGL_SAMPLE_BUFFERS_ARB
  #define WGL_SAMPLE_BUFFERS_ARB               0x2041
  #define WGL_SAMPLES_ARB                      0x2042
#endif

      // WGL_ARB_create_context_robustness
#ifndef WGL_CONTEXT_ROBUST_ACCESS_BIT_ARB
  #define WGL_CONTEXT_ROBUST_ACCESS_BIT_ARB 0x00000004
  #define WGL_CONTEXT_RESET_NOTIFICATION_STRATEGY_ARB 0x8256
  #define WGL_NO_RESET_NOTIFICATION_ARB               0x8261
  #define WGL_LOSE_CONTEXT_ON_RESET_ARB               0x8252
#endif

  typedef BOOL (WINAPI *wglChoosePixelFormatARB_t)
      (HDC           theDevCtx,
       const int*    theIntAttribs,
       const float*  theFloatAttribs,
       unsigned int  theMaxFormats,
       int*          theFormatsOut,
       unsigned int* theNumFormatsOut);
  wglChoosePixelFormatARB_t wglChoosePixelFormatARB;

  // WGL_ARB_create_context_profile

#ifndef WGL_CONTEXT_MAJOR_VERSION_ARB
  #define WGL_CONTEXT_MAJOR_VERSION_ARB           0x2091
  #define WGL_CONTEXT_MINOR_VERSION_ARB           0x2092
  #define WGL_CONTEXT_LAYER_PLANE_ARB             0x2093
  #define WGL_CONTEXT_FLAGS_ARB                   0x2094
  #define WGL_CONTEXT_PROFILE_MASK_ARB            0x9126

  // WGL_CONTEXT_FLAGS bits
  #define WGL_CONTEXT_DEBUG_BIT_ARB               0x0001
  #define WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB  0x0002

  // WGL_CONTEXT_PROFILE_MASK_ARB bits
  #define WGL_CONTEXT_CORE_PROFILE_BIT_ARB          0x00000001
  #define WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB 0x00000002
#endif // WGL_CONTEXT_MAJOR_VERSION_ARB

  typedef HGLRC (WINAPI *wglCreateContextAttribsARB_t)(HDC        theDevCtx,
                                                       HGLRC      theShareContext,
                                                       const int* theAttribs);
  wglCreateContextAttribsARB_t wglCreateContextAttribsARB;

  // WGL_NV_DX_interop

  typedef BOOL   (WINAPI *wglDXSetResourceShareHandleNV_t)(void* theObjectD3d, HANDLE theShareHandle);
  typedef HANDLE (WINAPI *wglDXOpenDeviceNV_t      )(void*   theDeviceD3d);
  typedef BOOL   (WINAPI *wglDXCloseDeviceNV_t     )(HANDLE  theDeviceIOP);
  typedef HANDLE (WINAPI *wglDXRegisterObjectNV_t  )(HANDLE  theDeviceIOP,
                                                     void*   theObjectD3d,
                                                     GLuint  theName,
                                                     GLenum  theType,
                                                     GLenum  theAccess);
  typedef BOOL   (WINAPI *wglDXUnregisterObjectNV_t)(HANDLE  theDeviceIOP,
                                                     HANDLE  theObject);
  typedef BOOL   (WINAPI *wglDXObjectAccessNV_t    )(HANDLE  theObject,
                                                     GLenum  theAccess);
  typedef BOOL   (WINAPI *wglDXLockObjectsNV_t     )(HANDLE  theDeviceIOP,
                                                     GLint   theCount,
                                                     HANDLE* theObjects);
  typedef BOOL   (WINAPI *wglDXUnlockObjectsNV_t   )(HANDLE  theDeviceIOP,
                                                     GLint   theCount,
                                                     HANDLE* theObjects);

  wglDXSetResourceShareHandleNV_t wglDXSetResourceShareHandleNV;
  wglDXOpenDeviceNV_t       wglDXOpenDeviceNV;
  wglDXCloseDeviceNV_t      wglDXCloseDeviceNV;
  wglDXRegisterObjectNV_t   wglDXRegisterObjectNV;
  wglDXUnregisterObjectNV_t wglDXUnregisterObjectNV;
  wglDXObjectAccessNV_t     wglDXObjectAccessNV;
  wglDXLockObjectsNV_t      wglDXLockObjectsNV;
  wglDXUnlockObjectsNV_t    wglDXUnlockObjectsNV;

#ifndef WGL_ACCESS_READ_WRITE_NV
  #define WGL_ACCESS_READ_ONLY_NV     0x0000
  #define WGL_ACCESS_READ_WRITE_NV    0x0001
  #define WGL_ACCESS_WRITE_DISCARD_NV 0x0002
#endif

  // WGL_AMD_gpu_association

#ifndef WGL_GPU_VENDOR_AMD
  #define WGL_GPU_VENDOR_AMD                 0x1F00
  #define WGL_GPU_RENDERER_STRING_AMD        0x1F01
  #define WGL_GPU_OPENGL_VERSION_STRING_AMD  0x1F02
  #define WGL_GPU_FASTEST_TARGET_GPUS_AMD    0x21A2
  #define WGL_GPU_RAM_AMD                    0x21A3
  #define WGL_GPU_CLOCK_AMD                  0x21A4
  #define WGL_GPU_NUM_PIPES_AMD              0x21A5
  #define WGL_GPU_NUM_SIMD_AMD               0x21A6
  #define WGL_GPU_NUM_RB_AMD                 0x21A7
  #define WGL_GPU_NUM_SPI_AMD                0x21A8
#endif

  typedef UINT (WINAPI *wglGetGPUIDsAMD_t       )(UINT theMaxCount, UINT* theIds);
  typedef INT  (WINAPI *wglGetGPUInfoAMD_t      )(UINT theId, INT theProperty, GLenum theDataType, UINT theSize, void* theData);
  typedef UINT (WINAPI *wglGetContextGPUIDAMD_t )(HGLRC theHglrc);
  wglGetGPUIDsAMD_t       wglGetGPUIDsAMD;
  wglGetGPUInfoAMD_t      wglGetGPUInfoAMD;
  wglGetContextGPUIDAMD_t wglGetContextGPUIDAMD;

#elif defined(__APPLE__)
public: //! @name CGL extensions

#else
public: //! @name glX extensions

  // GLX_EXT_swap_control
  //typedef int         (*glXSwapIntervalEXT_t)(Display* theDisplay, GLXDrawable theDrawable, int theInterval);
  typedef int         (*glXSwapIntervalEXT_t)();
  glXSwapIntervalEXT_t glXSwapIntervalEXT;

  typedef int         (*glXSwapIntervalSGI_t)(int theInterval);
  glXSwapIntervalSGI_t glXSwapIntervalSGI;

  // GLX_MESA_query_renderer
#ifndef GLX_RENDERER_VENDOR_ID_MESA
  // for glXQueryRendererIntegerMESA() and glXQueryCurrentRendererIntegerMESA()
  #define GLX_RENDERER_VENDOR_ID_MESA                      0x8183
  #define GLX_RENDERER_DEVICE_ID_MESA                      0x8184
  #define GLX_RENDERER_VERSION_MESA                        0x8185
  #define GLX_RENDERER_ACCELERATED_MESA                    0x8186
  #define GLX_RENDERER_VIDEO_MEMORY_MESA                   0x8187
  #define GLX_RENDERER_UNIFIED_MEMORY_ARCHITECTURE_MESA    0x8188
  #define GLX_RENDERER_PREFERRED_PROFILE_MESA              0x8189
  #define GLX_RENDERER_OPENGL_CORE_PROFILE_VERSION_MESA    0x818A
  #define GLX_RENDERER_OPENGL_COMPATIBILITY_PROFILE_VERSION_MESA 0x818B
  #define GLX_RENDERER_OPENGL_ES_PROFILE_VERSION_MESA      0x818C
  #define GLX_RENDERER_OPENGL_ES2_PROFILE_VERSION_MESA     0x818D

  #define GLX_RENDERER_ID_MESA                             0x818E
#endif // GLX_RENDERER_VENDOR_ID_MESA

  typedef int (*glXQueryRendererIntegerMESA_t)(Aspect_XDisplay* theDisplay, int theScreen,
                                               int theRenderer, int theAttribute,
                                               unsigned int* theValue);
  typedef int (*glXQueryCurrentRendererIntegerMESA_t)(int theAttribute, unsigned int* theValue);
  typedef const char* (*glXQueryRendererStringMESA_t)(Aspect_XDisplay* theDisplay, int theScreen,
                                                      int theRenderer, int theAttribute);
  typedef const char* (*glXQueryCurrentRendererStringMESA_t)(int theAttribute);

  glXQueryRendererIntegerMESA_t        glXQueryRendererIntegerMESA;
  glXQueryCurrentRendererIntegerMESA_t glXQueryCurrentRendererIntegerMESA;
  glXQueryRendererStringMESA_t         glXQueryRendererStringMESA;
  glXQueryCurrentRendererStringMESA_t  glXQueryCurrentRendererStringMESA;
#endif

};

#endif // _OpenGl_GlFunctions_Header
