qglfunctions.cpp

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** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtOpenGL module of the Qt Toolkit.
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#include "qglfunctions.h"
#include "qgl_p.h"

QT_BEGIN_NAMESPACE

// Hidden private fields for additional extension data.
struct QGLFunctionsPrivateEx : public QGLFunctionsPrivate
{
    QGLFunctionsPrivateEx(const QGLContext *context = 0)
        : QGLFunctionsPrivate(context)
        , m_features(-1) {}

    int m_features;
};

#if QT_VERSION >= 0x040800
Q_GLOBAL_STATIC(QGLContextGroupResource<QGLFunctionsPrivateEx>, qt_gl_functions_resource)
#else
static void qt_gl_functions_free(void *data)
{
    delete reinterpret_cast<QGLFunctionsPrivateEx *>(data);
}

Q_GLOBAL_STATIC_WITH_ARGS(QGLContextResource, qt_gl_functions_resource, (qt_gl_functions_free))
#endif
static QGLFunctionsPrivateEx *qt_gl_functions(const QGLContext *context = 0)
{
    if (!context)
        context = QGLContext::currentContext();
    Q_ASSERT(context);
    QGLFunctionsPrivateEx *funcs =
        reinterpret_cast<QGLFunctionsPrivateEx *>
            (qt_gl_functions_resource()->value(context));
#if QT_VERSION < 0x040800
    if (!funcs) {
        funcs = new QGLFunctionsPrivateEx();
        qt_gl_functions_resource()->insert(context, funcs);
    }
#endif
    return funcs;
}

QGLFunctions::QGLFunctions()
    : d_ptr(0)
{
}

QGLFunctions::QGLFunctions(const QGLContext *context)
    : d_ptr(qt_gl_functions(context))
{
}

static int qt_gl_resolve_features()
{
#if defined(QT_OPENGL_ES_2)
    int features = QGLFunctions::Multitexture |
                   QGLFunctions::Shaders |
                   QGLFunctions::Buffers |
                   QGLFunctions::Framebuffers |
                   QGLFunctions::BlendColor |
                   QGLFunctions::BlendEquation |
                   QGLFunctions::BlendEquationSeparate |
                   QGLFunctions::BlendFuncSeparate |
                   QGLFunctions::BlendSubtract |
                   QGLFunctions::CompressedTextures |
                   QGLFunctions::Multisample |
                   QGLFunctions::StencilSeparate;
    QGLExtensionMatcher extensions;
    if (extensions.match("GL_OES_texture_npot"))
        features |= QGLFunctions::NPOTTextures;
    if (extensions.match("GL_IMG_texture_npot"))
        features |= QGLFunctions::NPOTTextures;
    return features;
#elif defined(QT_OPENGL_ES)
    int features = QGLFunctions::Multitexture |
                   QGLFunctions::Buffers |
                   QGLFunctions::CompressedTextures |
                   QGLFunctions::Multisample;
    QGLExtensionMatcher extensions;
    if (extensions.match("GL_OES_framebuffer_object"))
        features |= QGLFunctions::Framebuffers;
    if (extensions.match("GL_OES_blend_equation_separate"))
        features |= QGLFunctions::BlendEquationSeparate;
    if (extensions.match("GL_OES_blend_func_separate"))
        features |= QGLFunctions::BlendFuncSeparate;
    if (extensions.match("GL_OES_blend_subtract"))
        features |= QGLFunctions::BlendSubtract;
    if (extensions.match("GL_OES_texture_npot"))
        features |= QGLFunctions::NPOTTextures;
    if (extensions.match("GL_IMG_texture_npot"))
        features |= QGLFunctions::NPOTTextures;
    return features;
#else
    int features = 0;
    QGLFormat::OpenGLVersionFlags versions = QGLFormat::openGLVersionFlags();
    QGLExtensionMatcher extensions;

    // Recognize features by extension name.
    if (extensions.match("GL_ARB_multitexture"))
        features |= QGLFunctions::Multitexture;
    if (extensions.match("GL_ARB_shader_objects"))
        features |= QGLFunctions::Shaders;
    if (extensions.match("GL_EXT_framebuffer_object") ||
            extensions.match("GL_ARB_framebuffer_object"))
        features |= QGLFunctions::Framebuffers;
    if (extensions.match("GL_EXT_blend_color"))
        features |= QGLFunctions::BlendColor;
    if (extensions.match("GL_EXT_blend_equation_separate"))
        features |= QGLFunctions::BlendEquationSeparate;
    if (extensions.match("GL_EXT_blend_func_separate"))
        features |= QGLFunctions::BlendFuncSeparate;
    if (extensions.match("GL_EXT_blend_subtract"))
        features |= QGLFunctions::BlendSubtract;
    if (extensions.match("GL_ARB_texture_compression"))
        features |= QGLFunctions::CompressedTextures;
    if (extensions.match("GL_ARB_multisample"))
        features |= QGLFunctions::Multisample;
    if (extensions.match("GL_ARB_texture_non_power_of_two"))
        features |= QGLFunctions::NPOTTextures;

    // Recognize features by minimum OpenGL version.
    if (versions & QGLFormat::OpenGL_Version_1_2) {
        features |= QGLFunctions::BlendColor |
                    QGLFunctions::BlendEquation;
    }
    if (versions & QGLFormat::OpenGL_Version_1_3) {
        features |= QGLFunctions::Multitexture |
                    QGLFunctions::CompressedTextures |
                    QGLFunctions::Multisample;
    }
    if (versions & QGLFormat::OpenGL_Version_1_4)
        features |= QGLFunctions::BlendFuncSeparate;
    if (versions & QGLFormat::OpenGL_Version_1_5)
        features |= QGLFunctions::Buffers;
    if (versions & QGLFormat::OpenGL_Version_2_0) {
        features |= QGLFunctions::Shaders |
                    QGLFunctions::StencilSeparate |
                    QGLFunctions::BlendEquationSeparate |
                    QGLFunctions::NPOTTextures;
    }
    return features;
#endif
}

QGLFunctions::OpenGLFeatures QGLFunctions::openGLFeatures() const
{
    QGLFunctionsPrivateEx *d = static_cast<QGLFunctionsPrivateEx *>(d_ptr);
    if (!d)
        return 0;
    if (d->m_features == -1)
        d->m_features = qt_gl_resolve_features();
    return QGLFunctions::OpenGLFeatures(d->m_features);
}

bool QGLFunctions::hasOpenGLFeature(QGLFunctions::OpenGLFeature feature) const
{
    QGLFunctionsPrivateEx *d = static_cast<QGLFunctionsPrivateEx *>(d_ptr);
    if (!d)
        return false;
    if (d->m_features == -1)
        d->m_features = qt_gl_resolve_features();
    return (d->m_features & int(feature)) != 0;
}

void QGLFunctions::initializeGLFunctions(const QGLContext *context)
{
    d_ptr = qt_gl_functions(context);
}

#ifndef QT_OPENGL_ES_2

static void qglfResolveActiveTexture(GLenum texture)
{
    typedef void (QGLF_APIENTRYP type_glActiveTexture)(GLenum texture);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->activeTexture = (type_glActiveTexture)
        context->getProcAddress(QLatin1String("glActiveTexture"));
    if (!funcs->activeTexture) {
        funcs->activeTexture = (type_glActiveTexture)
            context->getProcAddress(QLatin1String("glActiveTextureARB"));
    }

    if (funcs->activeTexture)
        funcs->activeTexture(texture);
    else
        funcs->activeTexture = qglfResolveActiveTexture;
}

static void qglfResolveAttachShader(GLuint program, GLuint shader)
{
    typedef void (QGLF_APIENTRYP type_glAttachShader)(GLuint program, GLuint shader);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->attachShader = (type_glAttachShader)
        context->getProcAddress(QLatin1String("glAttachShader"));
    if (!funcs->attachShader) {
        funcs->attachShader = (type_glAttachShader)
            context->getProcAddress(QLatin1String("glAttachObjectARB"));
    }

    if (funcs->attachShader)
        funcs->attachShader(program, shader);
    else
        funcs->attachShader = qglfResolveAttachShader;
}

static void qglfResolveBindAttribLocation(GLuint program, GLuint index, const char* name)
{
    typedef void (QGLF_APIENTRYP type_glBindAttribLocation)(GLuint program, GLuint index, const char* name);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bindAttribLocation = (type_glBindAttribLocation)
        context->getProcAddress(QLatin1String("glBindAttribLocation"));
    if (!funcs->bindAttribLocation) {
        funcs->bindAttribLocation = (type_glBindAttribLocation)
            context->getProcAddress(QLatin1String("glBindAttribLocationARB"));
    }

    if (funcs->bindAttribLocation)
        funcs->bindAttribLocation(program, index, name);
    else
        funcs->bindAttribLocation = qglfResolveBindAttribLocation;
}

static void qglfResolveBindBuffer(GLenum target, GLuint buffer)
{
    typedef void (QGLF_APIENTRYP type_glBindBuffer)(GLenum target, GLuint buffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bindBuffer = (type_glBindBuffer)
        context->getProcAddress(QLatin1String("glBindBuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->bindBuffer) {
        funcs->bindBuffer = (type_glBindBuffer)
            context->getProcAddress(QLatin1String("glBindBufferOES"));
    }
#endif
    if (!funcs->bindBuffer) {
        funcs->bindBuffer = (type_glBindBuffer)
            context->getProcAddress(QLatin1String("glBindBufferEXT"));
    }
    if (!funcs->bindBuffer) {
        funcs->bindBuffer = (type_glBindBuffer)
            context->getProcAddress(QLatin1String("glBindBufferARB"));
    }

    if (funcs->bindBuffer)
        funcs->bindBuffer(target, buffer);
    else
        funcs->bindBuffer = qglfResolveBindBuffer;
}

static void qglfResolveBindFramebuffer(GLenum target, GLuint framebuffer)
{
    typedef void (QGLF_APIENTRYP type_glBindFramebuffer)(GLenum target, GLuint framebuffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bindFramebuffer = (type_glBindFramebuffer)
        context->getProcAddress(QLatin1String("glBindFramebuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->bindFramebuffer) {
        funcs->bindFramebuffer = (type_glBindFramebuffer)
            context->getProcAddress(QLatin1String("glBindFramebufferOES"));
    }
#endif
    if (!funcs->bindFramebuffer) {
        funcs->bindFramebuffer = (type_glBindFramebuffer)
            context->getProcAddress(QLatin1String("glBindFramebufferEXT"));
    }
    if (!funcs->bindFramebuffer) {
        funcs->bindFramebuffer = (type_glBindFramebuffer)
            context->getProcAddress(QLatin1String("glBindFramebufferARB"));
    }

    if (funcs->bindFramebuffer)
        funcs->bindFramebuffer(target, framebuffer);
    else
        funcs->bindFramebuffer = qglfResolveBindFramebuffer;
}

static void qglfResolveBindRenderbuffer(GLenum target, GLuint renderbuffer)
{
    typedef void (QGLF_APIENTRYP type_glBindRenderbuffer)(GLenum target, GLuint renderbuffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bindRenderbuffer = (type_glBindRenderbuffer)
        context->getProcAddress(QLatin1String("glBindRenderbuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->bindRenderbuffer) {
        funcs->bindRenderbuffer = (type_glBindRenderbuffer)
            context->getProcAddress(QLatin1String("glBindRenderbufferOES"));
    }
#endif
    if (!funcs->bindRenderbuffer) {
        funcs->bindRenderbuffer = (type_glBindRenderbuffer)
            context->getProcAddress(QLatin1String("glBindRenderbufferEXT"));
    }
    if (!funcs->bindRenderbuffer) {
        funcs->bindRenderbuffer = (type_glBindRenderbuffer)
            context->getProcAddress(QLatin1String("glBindRenderbufferARB"));
    }

    if (funcs->bindRenderbuffer)
        funcs->bindRenderbuffer(target, renderbuffer);
    else
        funcs->bindRenderbuffer = qglfResolveBindRenderbuffer;
}

static void qglfResolveBlendColor(GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha)
{
    typedef void (QGLF_APIENTRYP type_glBlendColor)(GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->blendColor = (type_glBlendColor)
        context->getProcAddress(QLatin1String("glBlendColor"));
#ifdef QT_OPENGL_ES
    if (!funcs->blendColor) {
        funcs->blendColor = (type_glBlendColor)
            context->getProcAddress(QLatin1String("glBlendColorOES"));
    }
#endif
    if (!funcs->blendColor) {
        funcs->blendColor = (type_glBlendColor)
            context->getProcAddress(QLatin1String("glBlendColorEXT"));
    }
    if (!funcs->blendColor) {
        funcs->blendColor = (type_glBlendColor)
            context->getProcAddress(QLatin1String("glBlendColorARB"));
    }

    if (funcs->blendColor)
        funcs->blendColor(red, green, blue, alpha);
    else
        funcs->blendColor = qglfResolveBlendColor;
}

static void qglfResolveBlendEquation(GLenum mode)
{
    typedef void (QGLF_APIENTRYP type_glBlendEquation)(GLenum mode);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->blendEquation = (type_glBlendEquation)
        context->getProcAddress(QLatin1String("glBlendEquation"));
#ifdef QT_OPENGL_ES
    if (!funcs->blendEquation) {
        funcs->blendEquation = (type_glBlendEquation)
            context->getProcAddress(QLatin1String("glBlendEquationOES"));
    }
#endif
    if (!funcs->blendEquation) {
        funcs->blendEquation = (type_glBlendEquation)
            context->getProcAddress(QLatin1String("glBlendEquationEXT"));
    }
    if (!funcs->blendEquation) {
        funcs->blendEquation = (type_glBlendEquation)
            context->getProcAddress(QLatin1String("glBlendEquationARB"));
    }

    if (funcs->blendEquation)
        funcs->blendEquation(mode);
    else
        funcs->blendEquation = qglfResolveBlendEquation;
}

static void qglfResolveBlendEquationSeparate(GLenum modeRGB, GLenum modeAlpha)
{
    typedef void (QGLF_APIENTRYP type_glBlendEquationSeparate)(GLenum modeRGB, GLenum modeAlpha);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->blendEquationSeparate = (type_glBlendEquationSeparate)
        context->getProcAddress(QLatin1String("glBlendEquationSeparate"));
#ifdef QT_OPENGL_ES
    if (!funcs->blendEquationSeparate) {
        funcs->blendEquationSeparate = (type_glBlendEquationSeparate)
            context->getProcAddress(QLatin1String("glBlendEquationSeparateOES"));
    }
#endif
    if (!funcs->blendEquationSeparate) {
        funcs->blendEquationSeparate = (type_glBlendEquationSeparate)
            context->getProcAddress(QLatin1String("glBlendEquationSeparateEXT"));
    }
    if (!funcs->blendEquationSeparate) {
        funcs->blendEquationSeparate = (type_glBlendEquationSeparate)
            context->getProcAddress(QLatin1String("glBlendEquationSeparateARB"));
    }

    if (funcs->blendEquationSeparate)
        funcs->blendEquationSeparate(modeRGB, modeAlpha);
    else
        funcs->blendEquationSeparate = qglfResolveBlendEquationSeparate;
}

static void qglfResolveBlendFuncSeparate(GLenum srcRGB, GLenum dstRGB, GLenum srcAlpha, GLenum dstAlpha)
{
    typedef void (QGLF_APIENTRYP type_glBlendFuncSeparate)(GLenum srcRGB, GLenum dstRGB, GLenum srcAlpha, GLenum dstAlpha);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->blendFuncSeparate = (type_glBlendFuncSeparate)
        context->getProcAddress(QLatin1String("glBlendFuncSeparate"));
#ifdef QT_OPENGL_ES
    if (!funcs->blendFuncSeparate) {
        funcs->blendFuncSeparate = (type_glBlendFuncSeparate)
            context->getProcAddress(QLatin1String("glBlendFuncSeparateOES"));
    }
#endif
    if (!funcs->blendFuncSeparate) {
        funcs->blendFuncSeparate = (type_glBlendFuncSeparate)
            context->getProcAddress(QLatin1String("glBlendFuncSeparateEXT"));
    }
    if (!funcs->blendFuncSeparate) {
        funcs->blendFuncSeparate = (type_glBlendFuncSeparate)
            context->getProcAddress(QLatin1String("glBlendFuncSeparateARB"));
    }

    if (funcs->blendFuncSeparate)
        funcs->blendFuncSeparate(srcRGB, dstRGB, srcAlpha, dstAlpha);
    else
        funcs->blendFuncSeparate = qglfResolveBlendFuncSeparate;
}

static void qglfResolveBufferData(GLenum target, qgl_GLsizeiptr size, const void* data, GLenum usage)
{
    typedef void (QGLF_APIENTRYP type_glBufferData)(GLenum target, qgl_GLsizeiptr size, const void* data, GLenum usage);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bufferData = (type_glBufferData)
        context->getProcAddress(QLatin1String("glBufferData"));
#ifdef QT_OPENGL_ES
    if (!funcs->bufferData) {
        funcs->bufferData = (type_glBufferData)
            context->getProcAddress(QLatin1String("glBufferDataOES"));
    }
#endif
    if (!funcs->bufferData) {
        funcs->bufferData = (type_glBufferData)
            context->getProcAddress(QLatin1String("glBufferDataEXT"));
    }
    if (!funcs->bufferData) {
        funcs->bufferData = (type_glBufferData)
            context->getProcAddress(QLatin1String("glBufferDataARB"));
    }

    if (funcs->bufferData)
        funcs->bufferData(target, size, data, usage);
    else
        funcs->bufferData = qglfResolveBufferData;
}

static void qglfResolveBufferSubData(GLenum target, qgl_GLintptr offset, qgl_GLsizeiptr size, const void* data)
{
    typedef void (QGLF_APIENTRYP type_glBufferSubData)(GLenum target, qgl_GLintptr offset, qgl_GLsizeiptr size, const void* data);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->bufferSubData = (type_glBufferSubData)
        context->getProcAddress(QLatin1String("glBufferSubData"));
#ifdef QT_OPENGL_ES
    if (!funcs->bufferSubData) {
        funcs->bufferSubData = (type_glBufferSubData)
            context->getProcAddress(QLatin1String("glBufferSubDataOES"));
    }
#endif
    if (!funcs->bufferSubData) {
        funcs->bufferSubData = (type_glBufferSubData)
            context->getProcAddress(QLatin1String("glBufferSubDataEXT"));
    }
    if (!funcs->bufferSubData) {
        funcs->bufferSubData = (type_glBufferSubData)
            context->getProcAddress(QLatin1String("glBufferSubDataARB"));
    }

    if (funcs->bufferSubData)
        funcs->bufferSubData(target, offset, size, data);
    else
        funcs->bufferSubData = qglfResolveBufferSubData;
}

static GLenum qglfResolveCheckFramebufferStatus(GLenum target)
{
    typedef GLenum (QGLF_APIENTRYP type_glCheckFramebufferStatus)(GLenum target);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->checkFramebufferStatus = (type_glCheckFramebufferStatus)
        context->getProcAddress(QLatin1String("glCheckFramebufferStatus"));
#ifdef QT_OPENGL_ES
    if (!funcs->checkFramebufferStatus) {
        funcs->checkFramebufferStatus = (type_glCheckFramebufferStatus)
            context->getProcAddress(QLatin1String("glCheckFramebufferStatusOES"));
    }
#endif
    if (!funcs->checkFramebufferStatus) {
        funcs->checkFramebufferStatus = (type_glCheckFramebufferStatus)
            context->getProcAddress(QLatin1String("glCheckFramebufferStatusEXT"));
    }
    if (!funcs->checkFramebufferStatus) {
        funcs->checkFramebufferStatus = (type_glCheckFramebufferStatus)
            context->getProcAddress(QLatin1String("glCheckFramebufferStatusARB"));
    }

    if (funcs->checkFramebufferStatus)
        return funcs->checkFramebufferStatus(target);
    funcs->checkFramebufferStatus = qglfResolveCheckFramebufferStatus;
    return GLenum(0);
}

static void qglfResolveCompileShader(GLuint shader)
{
    typedef void (QGLF_APIENTRYP type_glCompileShader)(GLuint shader);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->compileShader = (type_glCompileShader)
        context->getProcAddress(QLatin1String("glCompileShader"));
    if (!funcs->compileShader) {
        funcs->compileShader = (type_glCompileShader)
            context->getProcAddress(QLatin1String("glCompileShader"));
    }

    if (funcs->compileShader)
        funcs->compileShader(shader);
    else
        funcs->compileShader = qglfResolveCompileShader;
}

static void qglfResolveCompressedTexImage2D(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const void* data)
{
    typedef void (QGLF_APIENTRYP type_glCompressedTexImage2D)(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const void* data);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->compressedTexImage2D = (type_glCompressedTexImage2D)
        context->getProcAddress(QLatin1String("glCompressedTexImage2D"));
#ifdef QT_OPENGL_ES
    if (!funcs->compressedTexImage2D) {
        funcs->compressedTexImage2D = (type_glCompressedTexImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexImage2DOES"));
    }
#endif
    if (!funcs->compressedTexImage2D) {
        funcs->compressedTexImage2D = (type_glCompressedTexImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexImage2DEXT"));
    }
    if (!funcs->compressedTexImage2D) {
        funcs->compressedTexImage2D = (type_glCompressedTexImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexImage2DARB"));
    }

    if (funcs->compressedTexImage2D)
        funcs->compressedTexImage2D(target, level, internalformat, width, height, border, imageSize, data);
    else
        funcs->compressedTexImage2D = qglfResolveCompressedTexImage2D;
}

static void qglfResolveCompressedTexSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const void* data)
{
    typedef void (QGLF_APIENTRYP type_glCompressedTexSubImage2D)(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const void* data);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->compressedTexSubImage2D = (type_glCompressedTexSubImage2D)
        context->getProcAddress(QLatin1String("glCompressedTexSubImage2D"));
#ifdef QT_OPENGL_ES
    if (!funcs->compressedTexSubImage2D) {
        funcs->compressedTexSubImage2D = (type_glCompressedTexSubImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexSubImage2DOES"));
    }
#endif
    if (!funcs->compressedTexSubImage2D) {
        funcs->compressedTexSubImage2D = (type_glCompressedTexSubImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexSubImage2DEXT"));
    }
    if (!funcs->compressedTexSubImage2D) {
        funcs->compressedTexSubImage2D = (type_glCompressedTexSubImage2D)
            context->getProcAddress(QLatin1String("glCompressedTexSubImage2DARB"));
    }

    if (funcs->compressedTexSubImage2D)
        funcs->compressedTexSubImage2D(target, level, xoffset, yoffset, width, height, format, imageSize, data);
    else
        funcs->compressedTexSubImage2D = qglfResolveCompressedTexSubImage2D;
}

static GLuint qglfResolveCreateProgram()
{
    typedef GLuint (QGLF_APIENTRYP type_glCreateProgram)();

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->createProgram = (type_glCreateProgram)
        context->getProcAddress(QLatin1String("glCreateProgram"));
    if (!funcs->createProgram) {
        funcs->createProgram = (type_glCreateProgram)
            context->getProcAddress(QLatin1String("glCreateProgramObjectARB"));
    }

    if (funcs->createProgram)
        return funcs->createProgram();
    funcs->createProgram = qglfResolveCreateProgram;
    return GLuint(0);
}

static GLuint qglfResolveCreateShader(GLenum type)
{
    typedef GLuint (QGLF_APIENTRYP type_glCreateShader)(GLenum type);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->createShader = (type_glCreateShader)
        context->getProcAddress(QLatin1String("glCreateShader"));
    if (!funcs->createShader) {
        funcs->createShader = (type_glCreateShader)
            context->getProcAddress(QLatin1String("glCreateShaderObjectARB"));
    }

    if (funcs->createShader)
        return funcs->createShader(type);
    funcs->createShader = qglfResolveCreateShader;
    return GLuint(0);
}

static void qglfResolveDeleteBuffers(GLsizei n, const GLuint* buffers)
{
    typedef void (QGLF_APIENTRYP type_glDeleteBuffers)(GLsizei n, const GLuint* buffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->deleteBuffers = (type_glDeleteBuffers)
        context->getProcAddress(QLatin1String("glDeleteBuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->deleteBuffers) {
        funcs->deleteBuffers = (type_glDeleteBuffers)
            context->getProcAddress(QLatin1String("glDeleteBuffersOES"));
    }
#endif
    if (!funcs->deleteBuffers) {
        funcs->deleteBuffers = (type_glDeleteBuffers)
            context->getProcAddress(QLatin1String("glDeleteBuffersEXT"));
    }
    if (!funcs->deleteBuffers) {
        funcs->deleteBuffers = (type_glDeleteBuffers)
            context->getProcAddress(QLatin1String("glDeleteBuffersARB"));
    }

    if (funcs->deleteBuffers)
        funcs->deleteBuffers(n, buffers);
    else
        funcs->deleteBuffers = qglfResolveDeleteBuffers;
}

static void qglfResolveDeleteFramebuffers(GLsizei n, const GLuint* framebuffers)
{
    typedef void (QGLF_APIENTRYP type_glDeleteFramebuffers)(GLsizei n, const GLuint* framebuffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->deleteFramebuffers = (type_glDeleteFramebuffers)
        context->getProcAddress(QLatin1String("glDeleteFramebuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->deleteFramebuffers) {
        funcs->deleteFramebuffers = (type_glDeleteFramebuffers)
            context->getProcAddress(QLatin1String("glDeleteFramebuffersOES"));
    }
#endif
    if (!funcs->deleteFramebuffers) {
        funcs->deleteFramebuffers = (type_glDeleteFramebuffers)
            context->getProcAddress(QLatin1String("glDeleteFramebuffersEXT"));
    }
    if (!funcs->deleteFramebuffers) {
        funcs->deleteFramebuffers = (type_glDeleteFramebuffers)
            context->getProcAddress(QLatin1String("glDeleteFramebuffersARB"));
    }

    if (funcs->deleteFramebuffers)
        funcs->deleteFramebuffers(n, framebuffers);
    else
        funcs->deleteFramebuffers = qglfResolveDeleteFramebuffers;
}

static void qglfResolveDeleteProgram(GLuint program)
{
    typedef void (QGLF_APIENTRYP type_glDeleteProgram)(GLuint program);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->deleteProgram = (type_glDeleteProgram)
        context->getProcAddress(QLatin1String("glDeleteProgram"));
    if (!funcs->deleteProgram) {
        funcs->deleteProgram = (type_glDeleteProgram)
            context->getProcAddress(QLatin1String("glDeleteObjectARB"));
    }

    if (funcs->deleteProgram)
        funcs->deleteProgram(program);
    else
        funcs->deleteProgram = qglfResolveDeleteProgram;
}

static void qglfResolveDeleteRenderbuffers(GLsizei n, const GLuint* renderbuffers)
{
    typedef void (QGLF_APIENTRYP type_glDeleteRenderbuffers)(GLsizei n, const GLuint* renderbuffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->deleteRenderbuffers = (type_glDeleteRenderbuffers)
        context->getProcAddress(QLatin1String("glDeleteRenderbuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->deleteRenderbuffers) {
        funcs->deleteRenderbuffers = (type_glDeleteRenderbuffers)
            context->getProcAddress(QLatin1String("glDeleteRenderbuffersOES"));
    }
#endif
    if (!funcs->deleteRenderbuffers) {
        funcs->deleteRenderbuffers = (type_glDeleteRenderbuffers)
            context->getProcAddress(QLatin1String("glDeleteRenderbuffersEXT"));
    }
    if (!funcs->deleteRenderbuffers) {
        funcs->deleteRenderbuffers = (type_glDeleteRenderbuffers)
            context->getProcAddress(QLatin1String("glDeleteRenderbuffersARB"));
    }

    if (funcs->deleteRenderbuffers)
        funcs->deleteRenderbuffers(n, renderbuffers);
    else
        funcs->deleteRenderbuffers = qglfResolveDeleteRenderbuffers;
}

static void qglfResolveDeleteShader(GLuint shader)
{
    typedef void (QGLF_APIENTRYP type_glDeleteShader)(GLuint shader);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->deleteShader = (type_glDeleteShader)
        context->getProcAddress(QLatin1String("glDeleteShader"));
    if (!funcs->deleteShader) {
        funcs->deleteShader = (type_glDeleteShader)
            context->getProcAddress(QLatin1String("glDeleteObjectARB"));
    }

    if (funcs->deleteShader)
        funcs->deleteShader(shader);
    else
        funcs->deleteShader = qglfResolveDeleteShader;
}

static void qglfResolveDetachShader(GLuint program, GLuint shader)
{
    typedef void (QGLF_APIENTRYP type_glDetachShader)(GLuint program, GLuint shader);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->detachShader = (type_glDetachShader)
        context->getProcAddress(QLatin1String("glDetachShader"));
    if (!funcs->detachShader) {
        funcs->detachShader = (type_glDetachShader)
            context->getProcAddress(QLatin1String("glDetachObjectARB"));
    }

    if (funcs->detachShader)
        funcs->detachShader(program, shader);
    else
        funcs->detachShader = qglfResolveDetachShader;
}

static void qglfResolveDisableVertexAttribArray(GLuint index)
{
    typedef void (QGLF_APIENTRYP type_glDisableVertexAttribArray)(GLuint index);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->disableVertexAttribArray = (type_glDisableVertexAttribArray)
        context->getProcAddress(QLatin1String("glDisableVertexAttribArray"));
    if (!funcs->disableVertexAttribArray) {
        funcs->disableVertexAttribArray = (type_glDisableVertexAttribArray)
            context->getProcAddress(QLatin1String("glDisableVertexAttribArrayARB"));
    }

    if (funcs->disableVertexAttribArray)
        funcs->disableVertexAttribArray(index);
    else
        funcs->disableVertexAttribArray = qglfResolveDisableVertexAttribArray;
}

static void qglfResolveEnableVertexAttribArray(GLuint index)
{
    typedef void (QGLF_APIENTRYP type_glEnableVertexAttribArray)(GLuint index);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->enableVertexAttribArray = (type_glEnableVertexAttribArray)
        context->getProcAddress(QLatin1String("glEnableVertexAttribArray"));
    if (!funcs->enableVertexAttribArray) {
        funcs->enableVertexAttribArray = (type_glEnableVertexAttribArray)
            context->getProcAddress(QLatin1String("glEnableVertexAttribArrayARB"));
    }

    if (funcs->enableVertexAttribArray)
        funcs->enableVertexAttribArray(index);
    else
        funcs->enableVertexAttribArray = qglfResolveEnableVertexAttribArray;
}

static void qglfResolveFramebufferRenderbuffer(GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer)
{
    typedef void (QGLF_APIENTRYP type_glFramebufferRenderbuffer)(GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->framebufferRenderbuffer = (type_glFramebufferRenderbuffer)
        context->getProcAddress(QLatin1String("glFramebufferRenderbuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->framebufferRenderbuffer) {
        funcs->framebufferRenderbuffer = (type_glFramebufferRenderbuffer)
            context->getProcAddress(QLatin1String("glFramebufferRenderbufferOES"));
    }
#endif
    if (!funcs->framebufferRenderbuffer) {
        funcs->framebufferRenderbuffer = (type_glFramebufferRenderbuffer)
            context->getProcAddress(QLatin1String("glFramebufferRenderbufferEXT"));
    }
    if (!funcs->framebufferRenderbuffer) {
        funcs->framebufferRenderbuffer = (type_glFramebufferRenderbuffer)
            context->getProcAddress(QLatin1String("glFramebufferRenderbufferARB"));
    }

    if (funcs->framebufferRenderbuffer)
        funcs->framebufferRenderbuffer(target, attachment, renderbuffertarget, renderbuffer);
    else
        funcs->framebufferRenderbuffer = qglfResolveFramebufferRenderbuffer;
}

static void qglfResolveFramebufferTexture2D(GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level)
{
    typedef void (QGLF_APIENTRYP type_glFramebufferTexture2D)(GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->framebufferTexture2D = (type_glFramebufferTexture2D)
        context->getProcAddress(QLatin1String("glFramebufferTexture2D"));
#ifdef QT_OPENGL_ES
    if (!funcs->framebufferTexture2D) {
        funcs->framebufferTexture2D = (type_glFramebufferTexture2D)
            context->getProcAddress(QLatin1String("glFramebufferTexture2DOES"));
    }
#endif
    if (!funcs->framebufferTexture2D) {
        funcs->framebufferTexture2D = (type_glFramebufferTexture2D)
            context->getProcAddress(QLatin1String("glFramebufferTexture2DEXT"));
    }
    if (!funcs->framebufferTexture2D) {
        funcs->framebufferTexture2D = (type_glFramebufferTexture2D)
            context->getProcAddress(QLatin1String("glFramebufferTexture2DARB"));
    }

    if (funcs->framebufferTexture2D)
        funcs->framebufferTexture2D(target, attachment, textarget, texture, level);
    else
        funcs->framebufferTexture2D = qglfResolveFramebufferTexture2D;
}

static void qglfResolveGenBuffers(GLsizei n, GLuint* buffers)
{
    typedef void (QGLF_APIENTRYP type_glGenBuffers)(GLsizei n, GLuint* buffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->genBuffers = (type_glGenBuffers)
        context->getProcAddress(QLatin1String("glGenBuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->genBuffers) {
        funcs->genBuffers = (type_glGenBuffers)
            context->getProcAddress(QLatin1String("glGenBuffersOES"));
    }
#endif
    if (!funcs->genBuffers) {
        funcs->genBuffers = (type_glGenBuffers)
            context->getProcAddress(QLatin1String("glGenBuffersEXT"));
    }
    if (!funcs->genBuffers) {
        funcs->genBuffers = (type_glGenBuffers)
            context->getProcAddress(QLatin1String("glGenBuffersARB"));
    }

    if (funcs->genBuffers)
        funcs->genBuffers(n, buffers);
    else
        funcs->genBuffers = qglfResolveGenBuffers;
}

static void qglfResolveGenerateMipmap(GLenum target)
{
    typedef void (QGLF_APIENTRYP type_glGenerateMipmap)(GLenum target);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->generateMipmap = (type_glGenerateMipmap)
        context->getProcAddress(QLatin1String("glGenerateMipmap"));
#ifdef QT_OPENGL_ES
    if (!funcs->generateMipmap) {
        funcs->generateMipmap = (type_glGenerateMipmap)
            context->getProcAddress(QLatin1String("glGenerateMipmapOES"));
    }
#endif
    if (!funcs->generateMipmap) {
        funcs->generateMipmap = (type_glGenerateMipmap)
            context->getProcAddress(QLatin1String("glGenerateMipmapEXT"));
    }
    if (!funcs->generateMipmap) {
        funcs->generateMipmap = (type_glGenerateMipmap)
            context->getProcAddress(QLatin1String("glGenerateMipmapARB"));
    }

    if (funcs->generateMipmap)
        funcs->generateMipmap(target);
    else
        funcs->generateMipmap = qglfResolveGenerateMipmap;
}

static void qglfResolveGenFramebuffers(GLsizei n, GLuint* framebuffers)
{
    typedef void (QGLF_APIENTRYP type_glGenFramebuffers)(GLsizei n, GLuint* framebuffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->genFramebuffers = (type_glGenFramebuffers)
        context->getProcAddress(QLatin1String("glGenFramebuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->genFramebuffers) {
        funcs->genFramebuffers = (type_glGenFramebuffers)
            context->getProcAddress(QLatin1String("glGenFramebuffersOES"));
    }
#endif
    if (!funcs->genFramebuffers) {
        funcs->genFramebuffers = (type_glGenFramebuffers)
            context->getProcAddress(QLatin1String("glGenFramebuffersEXT"));
    }
    if (!funcs->genFramebuffers) {
        funcs->genFramebuffers = (type_glGenFramebuffers)
            context->getProcAddress(QLatin1String("glGenFramebuffersARB"));
    }

    if (funcs->genFramebuffers)
        funcs->genFramebuffers(n, framebuffers);
    else
        funcs->genFramebuffers = qglfResolveGenFramebuffers;
}

static void qglfResolveGenRenderbuffers(GLsizei n, GLuint* renderbuffers)
{
    typedef void (QGLF_APIENTRYP type_glGenRenderbuffers)(GLsizei n, GLuint* renderbuffers);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->genRenderbuffers = (type_glGenRenderbuffers)
        context->getProcAddress(QLatin1String("glGenRenderbuffers"));
#ifdef QT_OPENGL_ES
    if (!funcs->genRenderbuffers) {
        funcs->genRenderbuffers = (type_glGenRenderbuffers)
            context->getProcAddress(QLatin1String("glGenRenderbuffersOES"));
    }
#endif
    if (!funcs->genRenderbuffers) {
        funcs->genRenderbuffers = (type_glGenRenderbuffers)
            context->getProcAddress(QLatin1String("glGenRenderbuffersEXT"));
    }
    if (!funcs->genRenderbuffers) {
        funcs->genRenderbuffers = (type_glGenRenderbuffers)
            context->getProcAddress(QLatin1String("glGenRenderbuffersARB"));
    }

    if (funcs->genRenderbuffers)
        funcs->genRenderbuffers(n, renderbuffers);
    else
        funcs->genRenderbuffers = qglfResolveGenRenderbuffers;
}

static void qglfResolveGetActiveAttrib(GLuint program, GLuint index, GLsizei bufsize, GLsizei* length, GLint* size, GLenum* type, char* name)
{
    typedef void (QGLF_APIENTRYP type_glGetActiveAttrib)(GLuint program, GLuint index, GLsizei bufsize, GLsizei* length, GLint* size, GLenum* type, char* name);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getActiveAttrib = (type_glGetActiveAttrib)
        context->getProcAddress(QLatin1String("glGetActiveAttrib"));
    if (!funcs->getActiveAttrib) {
        funcs->getActiveAttrib = (type_glGetActiveAttrib)
            context->getProcAddress(QLatin1String("glGetActiveAttribARB"));
    }

    if (funcs->getActiveAttrib)
        funcs->getActiveAttrib(program, index, bufsize, length, size, type, name);
    else
        funcs->getActiveAttrib = qglfResolveGetActiveAttrib;
}

static void qglfResolveGetActiveUniform(GLuint program, GLuint index, GLsizei bufsize, GLsizei* length, GLint* size, GLenum* type, char* name)
{
    typedef void (QGLF_APIENTRYP type_glGetActiveUniform)(GLuint program, GLuint index, GLsizei bufsize, GLsizei* length, GLint* size, GLenum* type, char* name);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getActiveUniform = (type_glGetActiveUniform)
        context->getProcAddress(QLatin1String("glGetActiveUniform"));
    if (!funcs->getActiveUniform) {
        funcs->getActiveUniform = (type_glGetActiveUniform)
            context->getProcAddress(QLatin1String("glGetActiveUniformARB"));
    }

    if (funcs->getActiveUniform)
        funcs->getActiveUniform(program, index, bufsize, length, size, type, name);
    else
        funcs->getActiveUniform = qglfResolveGetActiveUniform;
}

static void qglfResolveGetAttachedShaders(GLuint program, GLsizei maxcount, GLsizei* count, GLuint* shaders)
{
    typedef void (QGLF_APIENTRYP type_glGetAttachedShaders)(GLuint program, GLsizei maxcount, GLsizei* count, GLuint* shaders);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getAttachedShaders = (type_glGetAttachedShaders)
        context->getProcAddress(QLatin1String("glGetAttachedShaders"));
    if (!funcs->getAttachedShaders) {
        funcs->getAttachedShaders = (type_glGetAttachedShaders)
            context->getProcAddress(QLatin1String("glGetAttachedObjectsARB"));
    }

    if (funcs->getAttachedShaders)
        funcs->getAttachedShaders(program, maxcount, count, shaders);
    else
        funcs->getAttachedShaders = qglfResolveGetAttachedShaders;
}

static int qglfResolveGetAttribLocation(GLuint program, const char* name)
{
    typedef int (QGLF_APIENTRYP type_glGetAttribLocation)(GLuint program, const char* name);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getAttribLocation = (type_glGetAttribLocation)
        context->getProcAddress(QLatin1String("glGetAttribLocation"));
    if (!funcs->getAttribLocation) {
        funcs->getAttribLocation = (type_glGetAttribLocation)
            context->getProcAddress(QLatin1String("glGetAttribLocationARB"));
    }

    if (funcs->getAttribLocation)
        return funcs->getAttribLocation(program, name);
    funcs->getAttribLocation = qglfResolveGetAttribLocation;
    return int(0);
}

static void qglfResolveGetBufferParameteriv(GLenum target, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetBufferParameteriv)(GLenum target, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getBufferParameteriv = (type_glGetBufferParameteriv)
        context->getProcAddress(QLatin1String("glGetBufferParameteriv"));
#ifdef QT_OPENGL_ES
    if (!funcs->getBufferParameteriv) {
        funcs->getBufferParameteriv = (type_glGetBufferParameteriv)
            context->getProcAddress(QLatin1String("glGetBufferParameterivOES"));
    }
#endif
    if (!funcs->getBufferParameteriv) {
        funcs->getBufferParameteriv = (type_glGetBufferParameteriv)
            context->getProcAddress(QLatin1String("glGetBufferParameterivEXT"));
    }
    if (!funcs->getBufferParameteriv) {
        funcs->getBufferParameteriv = (type_glGetBufferParameteriv)
            context->getProcAddress(QLatin1String("glGetBufferParameterivARB"));
    }

    if (funcs->getBufferParameteriv)
        funcs->getBufferParameteriv(target, pname, params);
    else
        funcs->getBufferParameteriv = qglfResolveGetBufferParameteriv;
}

static void qglfResolveGetFramebufferAttachmentParameteriv(GLenum target, GLenum attachment, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetFramebufferAttachmentParameteriv)(GLenum target, GLenum attachment, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getFramebufferAttachmentParameteriv = (type_glGetFramebufferAttachmentParameteriv)
        context->getProcAddress(QLatin1String("glGetFramebufferAttachmentParameteriv"));
#ifdef QT_OPENGL_ES
    if (!funcs->getFramebufferAttachmentParameteriv) {
        funcs->getFramebufferAttachmentParameteriv = (type_glGetFramebufferAttachmentParameteriv)
            context->getProcAddress(QLatin1String("glGetFramebufferAttachmentParameterivOES"));
    }
#endif
    if (!funcs->getFramebufferAttachmentParameteriv) {
        funcs->getFramebufferAttachmentParameteriv = (type_glGetFramebufferAttachmentParameteriv)
            context->getProcAddress(QLatin1String("glGetFramebufferAttachmentParameterivEXT"));
    }
    if (!funcs->getFramebufferAttachmentParameteriv) {
        funcs->getFramebufferAttachmentParameteriv = (type_glGetFramebufferAttachmentParameteriv)
            context->getProcAddress(QLatin1String("glGetFramebufferAttachmentParameterivARB"));
    }

    if (funcs->getFramebufferAttachmentParameteriv)
        funcs->getFramebufferAttachmentParameteriv(target, attachment, pname, params);
    else
        funcs->getFramebufferAttachmentParameteriv = qglfResolveGetFramebufferAttachmentParameteriv;
}

static void qglfResolveGetProgramiv(GLuint program, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetProgramiv)(GLuint program, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getProgramiv = (type_glGetProgramiv)
        context->getProcAddress(QLatin1String("glGetProgramiv"));
    if (!funcs->getProgramiv) {
        funcs->getProgramiv = (type_glGetProgramiv)
            context->getProcAddress(QLatin1String("glGetObjectParameterivARB"));
    }

    if (funcs->getProgramiv)
        funcs->getProgramiv(program, pname, params);
    else
        funcs->getProgramiv = qglfResolveGetProgramiv;
}

static void qglfResolveGetProgramInfoLog(GLuint program, GLsizei bufsize, GLsizei* length, char* infolog)
{
    typedef void (QGLF_APIENTRYP type_glGetProgramInfoLog)(GLuint program, GLsizei bufsize, GLsizei* length, char* infolog);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getProgramInfoLog = (type_glGetProgramInfoLog)
        context->getProcAddress(QLatin1String("glGetProgramInfoLog"));
    if (!funcs->getProgramInfoLog) {
        funcs->getProgramInfoLog = (type_glGetProgramInfoLog)
            context->getProcAddress(QLatin1String("glGetInfoLogARB"));
    }

    if (funcs->getProgramInfoLog)
        funcs->getProgramInfoLog(program, bufsize, length, infolog);
    else
        funcs->getProgramInfoLog = qglfResolveGetProgramInfoLog;
}

static void qglfResolveGetRenderbufferParameteriv(GLenum target, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetRenderbufferParameteriv)(GLenum target, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getRenderbufferParameteriv = (type_glGetRenderbufferParameteriv)
        context->getProcAddress(QLatin1String("glGetRenderbufferParameteriv"));
#ifdef QT_OPENGL_ES
    if (!funcs->getRenderbufferParameteriv) {
        funcs->getRenderbufferParameteriv = (type_glGetRenderbufferParameteriv)
            context->getProcAddress(QLatin1String("glGetRenderbufferParameterivOES"));
    }
#endif
    if (!funcs->getRenderbufferParameteriv) {
        funcs->getRenderbufferParameteriv = (type_glGetRenderbufferParameteriv)
            context->getProcAddress(QLatin1String("glGetRenderbufferParameterivEXT"));
    }
    if (!funcs->getRenderbufferParameteriv) {
        funcs->getRenderbufferParameteriv = (type_glGetRenderbufferParameteriv)
            context->getProcAddress(QLatin1String("glGetRenderbufferParameterivARB"));
    }

    if (funcs->getRenderbufferParameteriv)
        funcs->getRenderbufferParameteriv(target, pname, params);
    else
        funcs->getRenderbufferParameteriv = qglfResolveGetRenderbufferParameteriv;
}

static void qglfResolveGetShaderiv(GLuint shader, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetShaderiv)(GLuint shader, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getShaderiv = (type_glGetShaderiv)
        context->getProcAddress(QLatin1String("glGetShaderiv"));
    if (!funcs->getShaderiv) {
        funcs->getShaderiv = (type_glGetShaderiv)
            context->getProcAddress(QLatin1String("glGetObjectParameterivARB"));
    }

    if (funcs->getShaderiv)
        funcs->getShaderiv(shader, pname, params);
    else
        funcs->getShaderiv = qglfResolveGetShaderiv;
}

static void qglfResolveGetShaderInfoLog(GLuint shader, GLsizei bufsize, GLsizei* length, char* infolog)
{
    typedef void (QGLF_APIENTRYP type_glGetShaderInfoLog)(GLuint shader, GLsizei bufsize, GLsizei* length, char* infolog);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getShaderInfoLog = (type_glGetShaderInfoLog)
        context->getProcAddress(QLatin1String("glGetShaderInfoLog"));
    if (!funcs->getShaderInfoLog) {
        funcs->getShaderInfoLog = (type_glGetShaderInfoLog)
            context->getProcAddress(QLatin1String("glGetInfoLogARB"));
    }

    if (funcs->getShaderInfoLog)
        funcs->getShaderInfoLog(shader, bufsize, length, infolog);
    else
        funcs->getShaderInfoLog = qglfResolveGetShaderInfoLog;
}

static void qglfSpecialGetShaderPrecisionFormat(GLenum shadertype, GLenum precisiontype, GLint* range, GLint* precision)
{
    Q_UNUSED(shadertype);
    Q_UNUSED(precisiontype);
    range[0] = range[1] = precision[0] = 0;
}

static void qglfResolveGetShaderPrecisionFormat(GLenum shadertype, GLenum precisiontype, GLint* range, GLint* precision)
{
    typedef void (QGLF_APIENTRYP type_glGetShaderPrecisionFormat)(GLenum shadertype, GLenum precisiontype, GLint* range, GLint* precision);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getShaderPrecisionFormat = (type_glGetShaderPrecisionFormat)
        context->getProcAddress(QLatin1String("glGetShaderPrecisionFormat"));
#ifdef QT_OPENGL_ES
    if (!funcs->getShaderPrecisionFormat) {
        funcs->getShaderPrecisionFormat = (type_glGetShaderPrecisionFormat)
            context->getProcAddress(QLatin1String("glGetShaderPrecisionFormatOES"));
    }
#endif
    if (!funcs->getShaderPrecisionFormat) {
        funcs->getShaderPrecisionFormat = (type_glGetShaderPrecisionFormat)
            context->getProcAddress(QLatin1String("glGetShaderPrecisionFormatEXT"));
    }
    if (!funcs->getShaderPrecisionFormat) {
        funcs->getShaderPrecisionFormat = (type_glGetShaderPrecisionFormat)
            context->getProcAddress(QLatin1String("glGetShaderPrecisionFormatARB"));
    }

    if (!funcs->getShaderPrecisionFormat)
        funcs->getShaderPrecisionFormat = qglfSpecialGetShaderPrecisionFormat;

    funcs->getShaderPrecisionFormat(shadertype, precisiontype, range, precision);
}

static void qglfResolveGetShaderSource(GLuint shader, GLsizei bufsize, GLsizei* length, char* source)
{
    typedef void (QGLF_APIENTRYP type_glGetShaderSource)(GLuint shader, GLsizei bufsize, GLsizei* length, char* source);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getShaderSource = (type_glGetShaderSource)
        context->getProcAddress(QLatin1String("glGetShaderSource"));
    if (!funcs->getShaderSource) {
        funcs->getShaderSource = (type_glGetShaderSource)
            context->getProcAddress(QLatin1String("glGetShaderSourceARB"));
    }

    if (funcs->getShaderSource)
        funcs->getShaderSource(shader, bufsize, length, source);
    else
        funcs->getShaderSource = qglfResolveGetShaderSource;
}

static void qglfResolveGetUniformfv(GLuint program, GLint location, GLfloat* params)
{
    typedef void (QGLF_APIENTRYP type_glGetUniformfv)(GLuint program, GLint location, GLfloat* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getUniformfv = (type_glGetUniformfv)
        context->getProcAddress(QLatin1String("glGetUniformfv"));
    if (!funcs->getUniformfv) {
        funcs->getUniformfv = (type_glGetUniformfv)
            context->getProcAddress(QLatin1String("glGetUniformfvARB"));
    }

    if (funcs->getUniformfv)
        funcs->getUniformfv(program, location, params);
    else
        funcs->getUniformfv = qglfResolveGetUniformfv;
}

static void qglfResolveGetUniformiv(GLuint program, GLint location, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetUniformiv)(GLuint program, GLint location, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getUniformiv = (type_glGetUniformiv)
        context->getProcAddress(QLatin1String("glGetUniformiv"));
    if (!funcs->getUniformiv) {
        funcs->getUniformiv = (type_glGetUniformiv)
            context->getProcAddress(QLatin1String("glGetUniformivARB"));
    }

    if (funcs->getUniformiv)
        funcs->getUniformiv(program, location, params);
    else
        funcs->getUniformiv = qglfResolveGetUniformiv;
}

static int qglfResolveGetUniformLocation(GLuint program, const char* name)
{
    typedef int (QGLF_APIENTRYP type_glGetUniformLocation)(GLuint program, const char* name);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getUniformLocation = (type_glGetUniformLocation)
        context->getProcAddress(QLatin1String("glGetUniformLocation"));
    if (!funcs->getUniformLocation) {
        funcs->getUniformLocation = (type_glGetUniformLocation)
            context->getProcAddress(QLatin1String("glGetUniformLocationARB"));
    }

    if (funcs->getUniformLocation)
        return funcs->getUniformLocation(program, name);
    funcs->getUniformLocation = qglfResolveGetUniformLocation;
    return int(0);
}

static void qglfResolveGetVertexAttribfv(GLuint index, GLenum pname, GLfloat* params)
{
    typedef void (QGLF_APIENTRYP type_glGetVertexAttribfv)(GLuint index, GLenum pname, GLfloat* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getVertexAttribfv = (type_glGetVertexAttribfv)
        context->getProcAddress(QLatin1String("glGetVertexAttribfv"));
    if (!funcs->getVertexAttribfv) {
        funcs->getVertexAttribfv = (type_glGetVertexAttribfv)
            context->getProcAddress(QLatin1String("glGetVertexAttribfvARB"));
    }

    if (funcs->getVertexAttribfv)
        funcs->getVertexAttribfv(index, pname, params);
    else
        funcs->getVertexAttribfv = qglfResolveGetVertexAttribfv;
}

static void qglfResolveGetVertexAttribiv(GLuint index, GLenum pname, GLint* params)
{
    typedef void (QGLF_APIENTRYP type_glGetVertexAttribiv)(GLuint index, GLenum pname, GLint* params);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getVertexAttribiv = (type_glGetVertexAttribiv)
        context->getProcAddress(QLatin1String("glGetVertexAttribiv"));
    if (!funcs->getVertexAttribiv) {
        funcs->getVertexAttribiv = (type_glGetVertexAttribiv)
            context->getProcAddress(QLatin1String("glGetVertexAttribivARB"));
    }

    if (funcs->getVertexAttribiv)
        funcs->getVertexAttribiv(index, pname, params);
    else
        funcs->getVertexAttribiv = qglfResolveGetVertexAttribiv;
}

static void qglfResolveGetVertexAttribPointerv(GLuint index, GLenum pname, void** pointer)
{
    typedef void (QGLF_APIENTRYP type_glGetVertexAttribPointerv)(GLuint index, GLenum pname, void** pointer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->getVertexAttribPointerv = (type_glGetVertexAttribPointerv)
        context->getProcAddress(QLatin1String("glGetVertexAttribPointerv"));
    if (!funcs->getVertexAttribPointerv) {
        funcs->getVertexAttribPointerv = (type_glGetVertexAttribPointerv)
            context->getProcAddress(QLatin1String("glGetVertexAttribPointervARB"));
    }

    if (funcs->getVertexAttribPointerv)
        funcs->getVertexAttribPointerv(index, pname, pointer);
    else
        funcs->getVertexAttribPointerv = qglfResolveGetVertexAttribPointerv;
}

static GLboolean qglfResolveIsBuffer(GLuint buffer)
{
    typedef GLboolean (QGLF_APIENTRYP type_glIsBuffer)(GLuint buffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->isBuffer = (type_glIsBuffer)
        context->getProcAddress(QLatin1String("glIsBuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->isBuffer) {
        funcs->isBuffer = (type_glIsBuffer)
            context->getProcAddress(QLatin1String("glIsBufferOES"));
    }
#endif
    if (!funcs->isBuffer) {
        funcs->isBuffer = (type_glIsBuffer)
            context->getProcAddress(QLatin1String("glIsBufferEXT"));
    }
    if (!funcs->isBuffer) {
        funcs->isBuffer = (type_glIsBuffer)
            context->getProcAddress(QLatin1String("glIsBufferARB"));
    }

    if (funcs->isBuffer)
        return funcs->isBuffer(buffer);
    funcs->isBuffer = qglfResolveIsBuffer;
    return GLboolean(0);
}

static GLboolean qglfResolveIsFramebuffer(GLuint framebuffer)
{
    typedef GLboolean (QGLF_APIENTRYP type_glIsFramebuffer)(GLuint framebuffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->isFramebuffer = (type_glIsFramebuffer)
        context->getProcAddress(QLatin1String("glIsFramebuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->isFramebuffer) {
        funcs->isFramebuffer = (type_glIsFramebuffer)
            context->getProcAddress(QLatin1String("glIsFramebufferOES"));
    }
#endif
    if (!funcs->isFramebuffer) {
        funcs->isFramebuffer = (type_glIsFramebuffer)
            context->getProcAddress(QLatin1String("glIsFramebufferEXT"));
    }
    if (!funcs->isFramebuffer) {
        funcs->isFramebuffer = (type_glIsFramebuffer)
            context->getProcAddress(QLatin1String("glIsFramebufferARB"));
    }

    if (funcs->isFramebuffer)
        return funcs->isFramebuffer(framebuffer);
    funcs->isFramebuffer = qglfResolveIsFramebuffer;
    return GLboolean(0);
}

static GLboolean qglfSpecialIsProgram(GLuint program)
{
    return program != 0;
}

static GLboolean qglfResolveIsProgram(GLuint program)
{
    typedef GLboolean (QGLF_APIENTRYP type_glIsProgram)(GLuint program);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->isProgram = (type_glIsProgram)
        context->getProcAddress(QLatin1String("glIsProgram"));
    if (!funcs->isProgram) {
        funcs->isProgram = (type_glIsProgram)
            context->getProcAddress(QLatin1String("glIsProgramARB"));
    }

    if (!funcs->isProgram)
        funcs->isProgram = qglfSpecialIsProgram;

    return funcs->isProgram(program);
}

static GLboolean qglfResolveIsRenderbuffer(GLuint renderbuffer)
{
    typedef GLboolean (QGLF_APIENTRYP type_glIsRenderbuffer)(GLuint renderbuffer);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->isRenderbuffer = (type_glIsRenderbuffer)
        context->getProcAddress(QLatin1String("glIsRenderbuffer"));
#ifdef QT_OPENGL_ES
    if (!funcs->isRenderbuffer) {
        funcs->isRenderbuffer = (type_glIsRenderbuffer)
            context->getProcAddress(QLatin1String("glIsRenderbufferOES"));
    }
#endif
    if (!funcs->isRenderbuffer) {
        funcs->isRenderbuffer = (type_glIsRenderbuffer)
            context->getProcAddress(QLatin1String("glIsRenderbufferEXT"));
    }
    if (!funcs->isRenderbuffer) {
        funcs->isRenderbuffer = (type_glIsRenderbuffer)
            context->getProcAddress(QLatin1String("glIsRenderbufferARB"));
    }

    if (funcs->isRenderbuffer)
        return funcs->isRenderbuffer(renderbuffer);
    funcs->isRenderbuffer = qglfResolveIsRenderbuffer;
    return GLboolean(0);
}

static GLboolean qglfSpecialIsShader(GLuint shader)
{
    return shader != 0;
}

static GLboolean qglfResolveIsShader(GLuint shader)
{
    typedef GLboolean (QGLF_APIENTRYP type_glIsShader)(GLuint shader);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->isShader = (type_glIsShader)
        context->getProcAddress(QLatin1String("glIsShader"));
    if (!funcs->isShader) {
        funcs->isShader = (type_glIsShader)
            context->getProcAddress(QLatin1String("glIsShaderARB"));
    }

    if (!funcs->isShader)
        funcs->isShader = qglfSpecialIsShader;

    return funcs->isShader(shader);
}

static void qglfResolveLinkProgram(GLuint program)
{
    typedef void (QGLF_APIENTRYP type_glLinkProgram)(GLuint program);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->linkProgram = (type_glLinkProgram)
        context->getProcAddress(QLatin1String("glLinkProgram"));
    if (!funcs->linkProgram) {
        funcs->linkProgram = (type_glLinkProgram)
            context->getProcAddress(QLatin1String("glLinkProgramARB"));
    }

    if (funcs->linkProgram)
        funcs->linkProgram(program);
    else
        funcs->linkProgram = qglfResolveLinkProgram;
}

static void qglfSpecialReleaseShaderCompiler()
{
}

static void qglfResolveReleaseShaderCompiler()
{
    typedef void (QGLF_APIENTRYP type_glReleaseShaderCompiler)();

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->releaseShaderCompiler = (type_glReleaseShaderCompiler)
        context->getProcAddress(QLatin1String("glReleaseShaderCompiler"));
    if (!funcs->releaseShaderCompiler) {
        funcs->releaseShaderCompiler = (type_glReleaseShaderCompiler)
            context->getProcAddress(QLatin1String("glReleaseShaderCompilerARB"));
    }

    if (!funcs->releaseShaderCompiler)
        funcs->releaseShaderCompiler = qglfSpecialReleaseShaderCompiler;

    funcs->releaseShaderCompiler();
}

static void qglfResolveRenderbufferStorage(GLenum target, GLenum internalformat, GLsizei width, GLsizei height)
{
    typedef void (QGLF_APIENTRYP type_glRenderbufferStorage)(GLenum target, GLenum internalformat, GLsizei width, GLsizei height);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->renderbufferStorage = (type_glRenderbufferStorage)
        context->getProcAddress(QLatin1String("glRenderbufferStorage"));
#ifdef QT_OPENGL_ES
    if (!funcs->renderbufferStorage) {
        funcs->renderbufferStorage = (type_glRenderbufferStorage)
            context->getProcAddress(QLatin1String("glRenderbufferStorageOES"));
    }
#endif
    if (!funcs->renderbufferStorage) {
        funcs->renderbufferStorage = (type_glRenderbufferStorage)
            context->getProcAddress(QLatin1String("glRenderbufferStorageEXT"));
    }
    if (!funcs->renderbufferStorage) {
        funcs->renderbufferStorage = (type_glRenderbufferStorage)
            context->getProcAddress(QLatin1String("glRenderbufferStorageARB"));
    }

    if (funcs->renderbufferStorage)
        funcs->renderbufferStorage(target, internalformat, width, height);
    else
        funcs->renderbufferStorage = qglfResolveRenderbufferStorage;
}

static void qglfResolveSampleCoverage(GLclampf value, GLboolean invert)
{
    typedef void (QGLF_APIENTRYP type_glSampleCoverage)(GLclampf value, GLboolean invert);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->sampleCoverage = (type_glSampleCoverage)
        context->getProcAddress(QLatin1String("glSampleCoverage"));
#ifdef QT_OPENGL_ES
    if (!funcs->sampleCoverage) {
        funcs->sampleCoverage = (type_glSampleCoverage)
            context->getProcAddress(QLatin1String("glSampleCoverageOES"));
    }
#endif
    if (!funcs->sampleCoverage) {
        funcs->sampleCoverage = (type_glSampleCoverage)
            context->getProcAddress(QLatin1String("glSampleCoverageEXT"));
    }
    if (!funcs->sampleCoverage) {
        funcs->sampleCoverage = (type_glSampleCoverage)
            context->getProcAddress(QLatin1String("glSampleCoverageARB"));
    }

    if (funcs->sampleCoverage)
        funcs->sampleCoverage(value, invert);
    else
        funcs->sampleCoverage = qglfResolveSampleCoverage;
}

static void qglfResolveShaderBinary(GLint n, const GLuint* shaders, GLenum binaryformat, const void* binary, GLint length)
{
    typedef void (QGLF_APIENTRYP type_glShaderBinary)(GLint n, const GLuint* shaders, GLenum binaryformat, const void* binary, GLint length);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->shaderBinary = (type_glShaderBinary)
        context->getProcAddress(QLatin1String("glShaderBinary"));
    if (!funcs->shaderBinary) {
        funcs->shaderBinary = (type_glShaderBinary)
            context->getProcAddress(QLatin1String("glShaderBinaryARB"));
    }

    if (funcs->shaderBinary)
        funcs->shaderBinary(n, shaders, binaryformat, binary, length);
    else
        funcs->shaderBinary = qglfResolveShaderBinary;
}

static void qglfResolveShaderSource(GLuint shader, GLsizei count, const char** string, const GLint* length)
{
    typedef void (QGLF_APIENTRYP type_glShaderSource)(GLuint shader, GLsizei count, const char** string, const GLint* length);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->shaderSource = (type_glShaderSource)
        context->getProcAddress(QLatin1String("glShaderSource"));
    if (!funcs->shaderSource) {
        funcs->shaderSource = (type_glShaderSource)
            context->getProcAddress(QLatin1String("glShaderSourceARB"));
    }

    if (funcs->shaderSource)
        funcs->shaderSource(shader, count, string, length);
    else
        funcs->shaderSource = qglfResolveShaderSource;
}

static void qglfResolveStencilFuncSeparate(GLenum face, GLenum func, GLint ref, GLuint mask)
{
    typedef void (QGLF_APIENTRYP type_glStencilFuncSeparate)(GLenum face, GLenum func, GLint ref, GLuint mask);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->stencilFuncSeparate = (type_glStencilFuncSeparate)
        context->getProcAddress(QLatin1String("glStencilFuncSeparate"));
#ifdef QT_OPENGL_ES
    if (!funcs->stencilFuncSeparate) {
        funcs->stencilFuncSeparate = (type_glStencilFuncSeparate)
            context->getProcAddress(QLatin1String("glStencilFuncSeparateOES"));
    }
#endif
    if (!funcs->stencilFuncSeparate) {
        funcs->stencilFuncSeparate = (type_glStencilFuncSeparate)
            context->getProcAddress(QLatin1String("glStencilFuncSeparateEXT"));
    }
    if (!funcs->stencilFuncSeparate) {
        funcs->stencilFuncSeparate = (type_glStencilFuncSeparate)
            context->getProcAddress(QLatin1String("glStencilFuncSeparateARB"));
    }

    if (funcs->stencilFuncSeparate)
        funcs->stencilFuncSeparate(face, func, ref, mask);
    else
        funcs->stencilFuncSeparate = qglfResolveStencilFuncSeparate;
}

static void qglfResolveStencilMaskSeparate(GLenum face, GLuint mask)
{
    typedef void (QGLF_APIENTRYP type_glStencilMaskSeparate)(GLenum face, GLuint mask);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->stencilMaskSeparate = (type_glStencilMaskSeparate)
        context->getProcAddress(QLatin1String("glStencilMaskSeparate"));
#ifdef QT_OPENGL_ES
    if (!funcs->stencilMaskSeparate) {
        funcs->stencilMaskSeparate = (type_glStencilMaskSeparate)
            context->getProcAddress(QLatin1String("glStencilMaskSeparateOES"));
    }
#endif
    if (!funcs->stencilMaskSeparate) {
        funcs->stencilMaskSeparate = (type_glStencilMaskSeparate)
            context->getProcAddress(QLatin1String("glStencilMaskSeparateEXT"));
    }
    if (!funcs->stencilMaskSeparate) {
        funcs->stencilMaskSeparate = (type_glStencilMaskSeparate)
            context->getProcAddress(QLatin1String("glStencilMaskSeparateARB"));
    }

    if (funcs->stencilMaskSeparate)
        funcs->stencilMaskSeparate(face, mask);
    else
        funcs->stencilMaskSeparate = qglfResolveStencilMaskSeparate;
}

static void qglfResolveStencilOpSeparate(GLenum face, GLenum fail, GLenum zfail, GLenum zpass)
{
    typedef void (QGLF_APIENTRYP type_glStencilOpSeparate)(GLenum face, GLenum fail, GLenum zfail, GLenum zpass);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->stencilOpSeparate = (type_glStencilOpSeparate)
        context->getProcAddress(QLatin1String("glStencilOpSeparate"));
#ifdef QT_OPENGL_ES
    if (!funcs->stencilOpSeparate) {
        funcs->stencilOpSeparate = (type_glStencilOpSeparate)
            context->getProcAddress(QLatin1String("glStencilOpSeparateOES"));
    }
#endif
    if (!funcs->stencilOpSeparate) {
        funcs->stencilOpSeparate = (type_glStencilOpSeparate)
            context->getProcAddress(QLatin1String("glStencilOpSeparateEXT"));
    }
    if (!funcs->stencilOpSeparate) {
        funcs->stencilOpSeparate = (type_glStencilOpSeparate)
            context->getProcAddress(QLatin1String("glStencilOpSeparateARB"));
    }

    if (funcs->stencilOpSeparate)
        funcs->stencilOpSeparate(face, fail, zfail, zpass);
    else
        funcs->stencilOpSeparate = qglfResolveStencilOpSeparate;
}

static void qglfResolveUniform1f(GLint location, GLfloat x)
{
    typedef void (QGLF_APIENTRYP type_glUniform1f)(GLint location, GLfloat x);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform1f = (type_glUniform1f)
        context->getProcAddress(QLatin1String("glUniform1f"));
    if (!funcs->uniform1f) {
        funcs->uniform1f = (type_glUniform1f)
            context->getProcAddress(QLatin1String("glUniform1fARB"));
    }

    if (funcs->uniform1f)
        funcs->uniform1f(location, x);
    else
        funcs->uniform1f = qglfResolveUniform1f;
}

static void qglfResolveUniform1fv(GLint location, GLsizei count, const GLfloat* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform1fv)(GLint location, GLsizei count, const GLfloat* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform1fv = (type_glUniform1fv)
        context->getProcAddress(QLatin1String("glUniform1fv"));
    if (!funcs->uniform1fv) {
        funcs->uniform1fv = (type_glUniform1fv)
            context->getProcAddress(QLatin1String("glUniform1fvARB"));
    }

    if (funcs->uniform1fv)
        funcs->uniform1fv(location, count, v);
    else
        funcs->uniform1fv = qglfResolveUniform1fv;
}

static void qglfResolveUniform1i(GLint location, GLint x)
{
    typedef void (QGLF_APIENTRYP type_glUniform1i)(GLint location, GLint x);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform1i = (type_glUniform1i)
        context->getProcAddress(QLatin1String("glUniform1i"));
    if (!funcs->uniform1i) {
        funcs->uniform1i = (type_glUniform1i)
            context->getProcAddress(QLatin1String("glUniform1iARB"));
    }

    if (funcs->uniform1i)
        funcs->uniform1i(location, x);
    else
        funcs->uniform1i = qglfResolveUniform1i;
}

static void qglfResolveUniform1iv(GLint location, GLsizei count, const GLint* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform1iv)(GLint location, GLsizei count, const GLint* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform1iv = (type_glUniform1iv)
        context->getProcAddress(QLatin1String("glUniform1iv"));
    if (!funcs->uniform1iv) {
        funcs->uniform1iv = (type_glUniform1iv)
            context->getProcAddress(QLatin1String("glUniform1ivARB"));
    }

    if (funcs->uniform1iv)
        funcs->uniform1iv(location, count, v);
    else
        funcs->uniform1iv = qglfResolveUniform1iv;
}

static void qglfResolveUniform2f(GLint location, GLfloat x, GLfloat y)
{
    typedef void (QGLF_APIENTRYP type_glUniform2f)(GLint location, GLfloat x, GLfloat y);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform2f = (type_glUniform2f)
        context->getProcAddress(QLatin1String("glUniform2f"));
    if (!funcs->uniform2f) {
        funcs->uniform2f = (type_glUniform2f)
            context->getProcAddress(QLatin1String("glUniform2fARB"));
    }

    if (funcs->uniform2f)
        funcs->uniform2f(location, x, y);
    else
        funcs->uniform2f = qglfResolveUniform2f;
}

static void qglfResolveUniform2fv(GLint location, GLsizei count, const GLfloat* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform2fv)(GLint location, GLsizei count, const GLfloat* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform2fv = (type_glUniform2fv)
        context->getProcAddress(QLatin1String("glUniform2fv"));
    if (!funcs->uniform2fv) {
        funcs->uniform2fv = (type_glUniform2fv)
            context->getProcAddress(QLatin1String("glUniform2fvARB"));
    }

    if (funcs->uniform2fv)
        funcs->uniform2fv(location, count, v);
    else
        funcs->uniform2fv = qglfResolveUniform2fv;
}

static void qglfResolveUniform2i(GLint location, GLint x, GLint y)
{
    typedef void (QGLF_APIENTRYP type_glUniform2i)(GLint location, GLint x, GLint y);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform2i = (type_glUniform2i)
        context->getProcAddress(QLatin1String("glUniform2i"));
    if (!funcs->uniform2i) {
        funcs->uniform2i = (type_glUniform2i)
            context->getProcAddress(QLatin1String("glUniform2iARB"));
    }

    if (funcs->uniform2i)
        funcs->uniform2i(location, x, y);
    else
        funcs->uniform2i = qglfResolveUniform2i;
}

static void qglfResolveUniform2iv(GLint location, GLsizei count, const GLint* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform2iv)(GLint location, GLsizei count, const GLint* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform2iv = (type_glUniform2iv)
        context->getProcAddress(QLatin1String("glUniform2iv"));
    if (!funcs->uniform2iv) {
        funcs->uniform2iv = (type_glUniform2iv)
            context->getProcAddress(QLatin1String("glUniform2ivARB"));
    }

    if (funcs->uniform2iv)
        funcs->uniform2iv(location, count, v);
    else
        funcs->uniform2iv = qglfResolveUniform2iv;
}

static void qglfResolveUniform3f(GLint location, GLfloat x, GLfloat y, GLfloat z)
{
    typedef void (QGLF_APIENTRYP type_glUniform3f)(GLint location, GLfloat x, GLfloat y, GLfloat z);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform3f = (type_glUniform3f)
        context->getProcAddress(QLatin1String("glUniform3f"));
    if (!funcs->uniform3f) {
        funcs->uniform3f = (type_glUniform3f)
            context->getProcAddress(QLatin1String("glUniform3fARB"));
    }

    if (funcs->uniform3f)
        funcs->uniform3f(location, x, y, z);
    else
        funcs->uniform3f = qglfResolveUniform3f;
}

static void qglfResolveUniform3fv(GLint location, GLsizei count, const GLfloat* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform3fv)(GLint location, GLsizei count, const GLfloat* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform3fv = (type_glUniform3fv)
        context->getProcAddress(QLatin1String("glUniform3fv"));
    if (!funcs->uniform3fv) {
        funcs->uniform3fv = (type_glUniform3fv)
            context->getProcAddress(QLatin1String("glUniform3fvARB"));
    }

    if (funcs->uniform3fv)
        funcs->uniform3fv(location, count, v);
    else
        funcs->uniform3fv = qglfResolveUniform3fv;
}

static void qglfResolveUniform3i(GLint location, GLint x, GLint y, GLint z)
{
    typedef void (QGLF_APIENTRYP type_glUniform3i)(GLint location, GLint x, GLint y, GLint z);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform3i = (type_glUniform3i)
        context->getProcAddress(QLatin1String("glUniform3i"));
    if (!funcs->uniform3i) {
        funcs->uniform3i = (type_glUniform3i)
            context->getProcAddress(QLatin1String("glUniform3iARB"));
    }

    if (funcs->uniform3i)
        funcs->uniform3i(location, x, y, z);
    else
        funcs->uniform3i = qglfResolveUniform3i;
}

static void qglfResolveUniform3iv(GLint location, GLsizei count, const GLint* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform3iv)(GLint location, GLsizei count, const GLint* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform3iv = (type_glUniform3iv)
        context->getProcAddress(QLatin1String("glUniform3iv"));
    if (!funcs->uniform3iv) {
        funcs->uniform3iv = (type_glUniform3iv)
            context->getProcAddress(QLatin1String("glUniform3ivARB"));
    }

    if (funcs->uniform3iv)
        funcs->uniform3iv(location, count, v);
    else
        funcs->uniform3iv = qglfResolveUniform3iv;
}

static void qglfResolveUniform4f(GLint location, GLfloat x, GLfloat y, GLfloat z, GLfloat w)
{
    typedef void (QGLF_APIENTRYP type_glUniform4f)(GLint location, GLfloat x, GLfloat y, GLfloat z, GLfloat w);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform4f = (type_glUniform4f)
        context->getProcAddress(QLatin1String("glUniform4f"));
    if (!funcs->uniform4f) {
        funcs->uniform4f = (type_glUniform4f)
            context->getProcAddress(QLatin1String("glUniform4fARB"));
    }

    if (funcs->uniform4f)
        funcs->uniform4f(location, x, y, z, w);
    else
        funcs->uniform4f = qglfResolveUniform4f;
}

static void qglfResolveUniform4fv(GLint location, GLsizei count, const GLfloat* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform4fv)(GLint location, GLsizei count, const GLfloat* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform4fv = (type_glUniform4fv)
        context->getProcAddress(QLatin1String("glUniform4fv"));
    if (!funcs->uniform4fv) {
        funcs->uniform4fv = (type_glUniform4fv)
            context->getProcAddress(QLatin1String("glUniform4fvARB"));
    }

    if (funcs->uniform4fv)
        funcs->uniform4fv(location, count, v);
    else
        funcs->uniform4fv = qglfResolveUniform4fv;
}

static void qglfResolveUniform4i(GLint location, GLint x, GLint y, GLint z, GLint w)
{
    typedef void (QGLF_APIENTRYP type_glUniform4i)(GLint location, GLint x, GLint y, GLint z, GLint w);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform4i = (type_glUniform4i)
        context->getProcAddress(QLatin1String("glUniform4i"));
    if (!funcs->uniform4i) {
        funcs->uniform4i = (type_glUniform4i)
            context->getProcAddress(QLatin1String("glUniform4iARB"));
    }

    if (funcs->uniform4i)
        funcs->uniform4i(location, x, y, z, w);
    else
        funcs->uniform4i = qglfResolveUniform4i;
}

static void qglfResolveUniform4iv(GLint location, GLsizei count, const GLint* v)
{
    typedef void (QGLF_APIENTRYP type_glUniform4iv)(GLint location, GLsizei count, const GLint* v);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniform4iv = (type_glUniform4iv)
        context->getProcAddress(QLatin1String("glUniform4iv"));
    if (!funcs->uniform4iv) {
        funcs->uniform4iv = (type_glUniform4iv)
            context->getProcAddress(QLatin1String("glUniform4ivARB"));
    }

    if (funcs->uniform4iv)
        funcs->uniform4iv(location, count, v);
    else
        funcs->uniform4iv = qglfResolveUniform4iv;
}

static void qglfResolveUniformMatrix2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value)
{
    typedef void (QGLF_APIENTRYP type_glUniformMatrix2fv)(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniformMatrix2fv = (type_glUniformMatrix2fv)
        context->getProcAddress(QLatin1String("glUniformMatrix2fv"));
    if (!funcs->uniformMatrix2fv) {
        funcs->uniformMatrix2fv = (type_glUniformMatrix2fv)
            context->getProcAddress(QLatin1String("glUniformMatrix2fvARB"));
    }

    if (funcs->uniformMatrix2fv)
        funcs->uniformMatrix2fv(location, count, transpose, value);
    else
        funcs->uniformMatrix2fv = qglfResolveUniformMatrix2fv;
}

static void qglfResolveUniformMatrix3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value)
{
    typedef void (QGLF_APIENTRYP type_glUniformMatrix3fv)(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniformMatrix3fv = (type_glUniformMatrix3fv)
        context->getProcAddress(QLatin1String("glUniformMatrix3fv"));
    if (!funcs->uniformMatrix3fv) {
        funcs->uniformMatrix3fv = (type_glUniformMatrix3fv)
            context->getProcAddress(QLatin1String("glUniformMatrix3fvARB"));
    }

    if (funcs->uniformMatrix3fv)
        funcs->uniformMatrix3fv(location, count, transpose, value);
    else
        funcs->uniformMatrix3fv = qglfResolveUniformMatrix3fv;
}

static void qglfResolveUniformMatrix4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value)
{
    typedef void (QGLF_APIENTRYP type_glUniformMatrix4fv)(GLint location, GLsizei count, GLboolean transpose, const GLfloat* value);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->uniformMatrix4fv = (type_glUniformMatrix4fv)
        context->getProcAddress(QLatin1String("glUniformMatrix4fv"));
    if (!funcs->uniformMatrix4fv) {
        funcs->uniformMatrix4fv = (type_glUniformMatrix4fv)
            context->getProcAddress(QLatin1String("glUniformMatrix4fvARB"));
    }

    if (funcs->uniformMatrix4fv)
        funcs->uniformMatrix4fv(location, count, transpose, value);
    else
        funcs->uniformMatrix4fv = qglfResolveUniformMatrix4fv;
}

static void qglfResolveUseProgram(GLuint program)
{
    typedef void (QGLF_APIENTRYP type_glUseProgram)(GLuint program);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->useProgram = (type_glUseProgram)
        context->getProcAddress(QLatin1String("glUseProgram"));
    if (!funcs->useProgram) {
        funcs->useProgram = (type_glUseProgram)
            context->getProcAddress(QLatin1String("glUseProgramObjectARB"));
    }

    if (funcs->useProgram)
        funcs->useProgram(program);
    else
        funcs->useProgram = qglfResolveUseProgram;
}

static void qglfResolveValidateProgram(GLuint program)
{
    typedef void (QGLF_APIENTRYP type_glValidateProgram)(GLuint program);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->validateProgram = (type_glValidateProgram)
        context->getProcAddress(QLatin1String("glValidateProgram"));
    if (!funcs->validateProgram) {
        funcs->validateProgram = (type_glValidateProgram)
            context->getProcAddress(QLatin1String("glValidateProgramARB"));
    }

    if (funcs->validateProgram)
        funcs->validateProgram(program);
    else
        funcs->validateProgram = qglfResolveValidateProgram;
}

static void qglfResolveVertexAttrib1f(GLuint indx, GLfloat x)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib1f)(GLuint indx, GLfloat x);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib1f = (type_glVertexAttrib1f)
        context->getProcAddress(QLatin1String("glVertexAttrib1f"));
    if (!funcs->vertexAttrib1f) {
        funcs->vertexAttrib1f = (type_glVertexAttrib1f)
            context->getProcAddress(QLatin1String("glVertexAttrib1fARB"));
    }

    if (funcs->vertexAttrib1f)
        funcs->vertexAttrib1f(indx, x);
    else
        funcs->vertexAttrib1f = qglfResolveVertexAttrib1f;
}

static void qglfResolveVertexAttrib1fv(GLuint indx, const GLfloat* values)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib1fv)(GLuint indx, const GLfloat* values);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib1fv = (type_glVertexAttrib1fv)
        context->getProcAddress(QLatin1String("glVertexAttrib1fv"));
    if (!funcs->vertexAttrib1fv) {
        funcs->vertexAttrib1fv = (type_glVertexAttrib1fv)
            context->getProcAddress(QLatin1String("glVertexAttrib1fvARB"));
    }

    if (funcs->vertexAttrib1fv)
        funcs->vertexAttrib1fv(indx, values);
    else
        funcs->vertexAttrib1fv = qglfResolveVertexAttrib1fv;
}

static void qglfResolveVertexAttrib2f(GLuint indx, GLfloat x, GLfloat y)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib2f)(GLuint indx, GLfloat x, GLfloat y);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib2f = (type_glVertexAttrib2f)
        context->getProcAddress(QLatin1String("glVertexAttrib2f"));
    if (!funcs->vertexAttrib2f) {
        funcs->vertexAttrib2f = (type_glVertexAttrib2f)
            context->getProcAddress(QLatin1String("glVertexAttrib2fARB"));
    }

    if (funcs->vertexAttrib2f)
        funcs->vertexAttrib2f(indx, x, y);
    else
        funcs->vertexAttrib2f = qglfResolveVertexAttrib2f;
}

static void qglfResolveVertexAttrib2fv(GLuint indx, const GLfloat* values)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib2fv)(GLuint indx, const GLfloat* values);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib2fv = (type_glVertexAttrib2fv)
        context->getProcAddress(QLatin1String("glVertexAttrib2fv"));
    if (!funcs->vertexAttrib2fv) {
        funcs->vertexAttrib2fv = (type_glVertexAttrib2fv)
            context->getProcAddress(QLatin1String("glVertexAttrib2fvARB"));
    }

    if (funcs->vertexAttrib2fv)
        funcs->vertexAttrib2fv(indx, values);
    else
        funcs->vertexAttrib2fv = qglfResolveVertexAttrib2fv;
}

static void qglfResolveVertexAttrib3f(GLuint indx, GLfloat x, GLfloat y, GLfloat z)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib3f)(GLuint indx, GLfloat x, GLfloat y, GLfloat z);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib3f = (type_glVertexAttrib3f)
        context->getProcAddress(QLatin1String("glVertexAttrib3f"));
    if (!funcs->vertexAttrib3f) {
        funcs->vertexAttrib3f = (type_glVertexAttrib3f)
            context->getProcAddress(QLatin1String("glVertexAttrib3fARB"));
    }

    if (funcs->vertexAttrib3f)
        funcs->vertexAttrib3f(indx, x, y, z);
    else
        funcs->vertexAttrib3f = qglfResolveVertexAttrib3f;
}

static void qglfResolveVertexAttrib3fv(GLuint indx, const GLfloat* values)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib3fv)(GLuint indx, const GLfloat* values);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib3fv = (type_glVertexAttrib3fv)
        context->getProcAddress(QLatin1String("glVertexAttrib3fv"));
    if (!funcs->vertexAttrib3fv) {
        funcs->vertexAttrib3fv = (type_glVertexAttrib3fv)
            context->getProcAddress(QLatin1String("glVertexAttrib3fvARB"));
    }

    if (funcs->vertexAttrib3fv)
        funcs->vertexAttrib3fv(indx, values);
    else
        funcs->vertexAttrib3fv = qglfResolveVertexAttrib3fv;
}

static void qglfResolveVertexAttrib4f(GLuint indx, GLfloat x, GLfloat y, GLfloat z, GLfloat w)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib4f)(GLuint indx, GLfloat x, GLfloat y, GLfloat z, GLfloat w);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib4f = (type_glVertexAttrib4f)
        context->getProcAddress(QLatin1String("glVertexAttrib4f"));
    if (!funcs->vertexAttrib4f) {
        funcs->vertexAttrib4f = (type_glVertexAttrib4f)
            context->getProcAddress(QLatin1String("glVertexAttrib4fARB"));
    }

    if (funcs->vertexAttrib4f)
        funcs->vertexAttrib4f(indx, x, y, z, w);
    else
        funcs->vertexAttrib4f = qglfResolveVertexAttrib4f;
}

static void qglfResolveVertexAttrib4fv(GLuint indx, const GLfloat* values)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttrib4fv)(GLuint indx, const GLfloat* values);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttrib4fv = (type_glVertexAttrib4fv)
        context->getProcAddress(QLatin1String("glVertexAttrib4fv"));
    if (!funcs->vertexAttrib4fv) {
        funcs->vertexAttrib4fv = (type_glVertexAttrib4fv)
            context->getProcAddress(QLatin1String("glVertexAttrib4fvARB"));
    }

    if (funcs->vertexAttrib4fv)
        funcs->vertexAttrib4fv(indx, values);
    else
        funcs->vertexAttrib4fv = qglfResolveVertexAttrib4fv;
}

static void qglfResolveVertexAttribPointer(GLuint indx, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const void* ptr)
{
    typedef void (QGLF_APIENTRYP type_glVertexAttribPointer)(GLuint indx, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const void* ptr);

    const QGLContext *context = QGLContext::currentContext();
    QGLFunctionsPrivate *funcs = qt_gl_functions(context);

    funcs->vertexAttribPointer = (type_glVertexAttribPointer)
        context->getProcAddress(QLatin1String("glVertexAttribPointer"));
    if (!funcs->vertexAttribPointer) {
        funcs->vertexAttribPointer = (type_glVertexAttribPointer)
            context->getProcAddress(QLatin1String("glVertexAttribPointerARB"));
    }

    if (funcs->vertexAttribPointer)
        funcs->vertexAttribPointer(indx, size, type, normalized, stride, ptr);
    else
        funcs->vertexAttribPointer = qglfResolveVertexAttribPointer;
}

#endif // !QT_OPENGL_ES_2

QGLFunctionsPrivate::QGLFunctionsPrivate(const QGLContext *)
{
#ifndef QT_OPENGL_ES_2
    activeTexture = qglfResolveActiveTexture;
    attachShader = qglfResolveAttachShader;
    bindAttribLocation = qglfResolveBindAttribLocation;
    bindBuffer = qglfResolveBindBuffer;
    bindFramebuffer = qglfResolveBindFramebuffer;
    bindRenderbuffer = qglfResolveBindRenderbuffer;
    blendColor = qglfResolveBlendColor;
    blendEquation = qglfResolveBlendEquation;
    blendEquationSeparate = qglfResolveBlendEquationSeparate;
    blendFuncSeparate = qglfResolveBlendFuncSeparate;
    bufferData = qglfResolveBufferData;
    bufferSubData = qglfResolveBufferSubData;
    checkFramebufferStatus = qglfResolveCheckFramebufferStatus;
    compileShader = qglfResolveCompileShader;
    compressedTexImage2D = qglfResolveCompressedTexImage2D;
    compressedTexSubImage2D = qglfResolveCompressedTexSubImage2D;
    createProgram = qglfResolveCreateProgram;
    createShader = qglfResolveCreateShader;
    deleteBuffers = qglfResolveDeleteBuffers;
    deleteFramebuffers = qglfResolveDeleteFramebuffers;
    deleteProgram = qglfResolveDeleteProgram;
    deleteRenderbuffers = qglfResolveDeleteRenderbuffers;
    deleteShader = qglfResolveDeleteShader;
    detachShader = qglfResolveDetachShader;
    disableVertexAttribArray = qglfResolveDisableVertexAttribArray;
    enableVertexAttribArray = qglfResolveEnableVertexAttribArray;
    framebufferRenderbuffer = qglfResolveFramebufferRenderbuffer;
    framebufferTexture2D = qglfResolveFramebufferTexture2D;
    genBuffers = qglfResolveGenBuffers;
    generateMipmap = qglfResolveGenerateMipmap;
    genFramebuffers = qglfResolveGenFramebuffers;
    genRenderbuffers = qglfResolveGenRenderbuffers;
    getActiveAttrib = qglfResolveGetActiveAttrib;
    getActiveUniform = qglfResolveGetActiveUniform;
    getAttachedShaders = qglfResolveGetAttachedShaders;
    getAttribLocation = qglfResolveGetAttribLocation;
    getBufferParameteriv = qglfResolveGetBufferParameteriv;
    getFramebufferAttachmentParameteriv = qglfResolveGetFramebufferAttachmentParameteriv;
    getProgramiv = qglfResolveGetProgramiv;
    getProgramInfoLog = qglfResolveGetProgramInfoLog;
    getRenderbufferParameteriv = qglfResolveGetRenderbufferParameteriv;
    getShaderiv = qglfResolveGetShaderiv;
    getShaderInfoLog = qglfResolveGetShaderInfoLog;
    getShaderPrecisionFormat = qglfResolveGetShaderPrecisionFormat;
    getShaderSource = qglfResolveGetShaderSource;
    getUniformfv = qglfResolveGetUniformfv;
    getUniformiv = qglfResolveGetUniformiv;
    getUniformLocation = qglfResolveGetUniformLocation;
    getVertexAttribfv = qglfResolveGetVertexAttribfv;
    getVertexAttribiv = qglfResolveGetVertexAttribiv;
    getVertexAttribPointerv = qglfResolveGetVertexAttribPointerv;
    isBuffer = qglfResolveIsBuffer;
    isFramebuffer = qglfResolveIsFramebuffer;
    isProgram = qglfResolveIsProgram;
    isRenderbuffer = qglfResolveIsRenderbuffer;
    isShader = qglfResolveIsShader;
    linkProgram = qglfResolveLinkProgram;
    releaseShaderCompiler = qglfResolveReleaseShaderCompiler;
    renderbufferStorage = qglfResolveRenderbufferStorage;
    sampleCoverage = qglfResolveSampleCoverage;
    shaderBinary = qglfResolveShaderBinary;
    shaderSource = qglfResolveShaderSource;
    stencilFuncSeparate = qglfResolveStencilFuncSeparate;
    stencilMaskSeparate = qglfResolveStencilMaskSeparate;
    stencilOpSeparate = qglfResolveStencilOpSeparate;
    uniform1f = qglfResolveUniform1f;
    uniform1fv = qglfResolveUniform1fv;
    uniform1i = qglfResolveUniform1i;
    uniform1iv = qglfResolveUniform1iv;
    uniform2f = qglfResolveUniform2f;
    uniform2fv = qglfResolveUniform2fv;
    uniform2i = qglfResolveUniform2i;
    uniform2iv = qglfResolveUniform2iv;
    uniform3f = qglfResolveUniform3f;
    uniform3fv = qglfResolveUniform3fv;
    uniform3i = qglfResolveUniform3i;
    uniform3iv = qglfResolveUniform3iv;
    uniform4f = qglfResolveUniform4f;
    uniform4fv = qglfResolveUniform4fv;
    uniform4i = qglfResolveUniform4i;
    uniform4iv = qglfResolveUniform4iv;
    uniformMatrix2fv = qglfResolveUniformMatrix2fv;
    uniformMatrix3fv = qglfResolveUniformMatrix3fv;
    uniformMatrix4fv = qglfResolveUniformMatrix4fv;
    useProgram = qglfResolveUseProgram;
    validateProgram = qglfResolveValidateProgram;
    vertexAttrib1f = qglfResolveVertexAttrib1f;
    vertexAttrib1fv = qglfResolveVertexAttrib1fv;
    vertexAttrib2f = qglfResolveVertexAttrib2f;
    vertexAttrib2fv = qglfResolveVertexAttrib2fv;
    vertexAttrib3f = qglfResolveVertexAttrib3f;
    vertexAttrib3fv = qglfResolveVertexAttrib3fv;
    vertexAttrib4f = qglfResolveVertexAttrib4f;
    vertexAttrib4fv = qglfResolveVertexAttrib4fv;
    vertexAttribPointer = qglfResolveVertexAttribPointer;
#endif // !QT_OPENGL_ES_2
}

QT_END_NAMESPACE