source: trunk/src/opengl/qglextensions.cpp@ 715

/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation ([email protected])
**
** This file is part of the QtOpenGL module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
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** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
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** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
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** If you have questions regarding the use of this file, please contact
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#include "qgl_p.h"

QT_BEGIN_NAMESPACE

static void *qt_gl_getProcAddress_search
    (QGLContext *ctx, const char *name1, const char *name2,
     const char *name3, const char *name4)
{
    void *addr;

    addr = ctx->getProcAddress(QLatin1String(name1));
    if (addr)
        return addr;

    addr = ctx->getProcAddress(QLatin1String(name2));
    if (addr)
        return addr;

    addr = ctx->getProcAddress(QLatin1String(name3));
    if (addr)
        return addr;

    if (name4)
        return ctx->getProcAddress(QLatin1String(name4));

    return 0;
}

// Search for an extension function starting with the most likely
// function suffix first, and then trying the other variations.
#if defined(QT_OPENGL_ES)
#define qt_gl_getProcAddress(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name, name "OES", name "EXT", name "ARB")
#define qt_gl_getProcAddressEXT(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "OES", name, name "EXT", name "ARB")
#define qt_gl_getProcAddressARB(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "OES", name, name "ARB", name "EXT")
#define qt_gl_getProcAddressOES(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "OES", name, name "EXT", name "ARB")
#else
#define qt_gl_getProcAddress(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name, name "ARB", name "EXT", 0)
#define qt_gl_getProcAddressEXT(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "EXT", name, name "ARB", 0)
#define qt_gl_getProcAddressARB(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "ARB", name, name "EXT", 0)
#define qt_gl_getProcAddressOES(ctx,name) \
    qt_gl_getProcAddress_search((ctx), name "OES", name, name "EXT", name "ARB")
#endif

bool qt_resolve_framebufferobject_extensions(QGLContext *ctx)
{
#if defined(QT_OPENGL_ES_2)
    static bool have_resolved = false;
    if (have_resolved)
        return true;
    have_resolved = true;
#else
    if (glIsRenderbuffer != 0)
        return true;
#endif

    if (ctx == 0) {
        qWarning("QGLFramebufferObject: Unable to resolve framebuffer object extensions -"
                 " make sure there is a current context when creating the framebuffer object.");
        return false;
    }


    glBlitFramebufferEXT = (_glBlitFramebufferEXT) qt_gl_getProcAddressEXT(ctx, "glBlitFramebuffer");
    glRenderbufferStorageMultisampleEXT =
        (_glRenderbufferStorageMultisampleEXT) qt_gl_getProcAddressEXT(ctx, "glRenderbufferStorageMultisample");

#if !defined(QT_OPENGL_ES_2)
    glIsRenderbuffer = (_glIsRenderbuffer) qt_gl_getProcAddressEXT(ctx, "glIsRenderbuffer");
    if (!glIsRenderbuffer)
        return false;   // Not much point searching for anything else.
    glBindRenderbuffer = (_glBindRenderbuffer) qt_gl_getProcAddressEXT(ctx, "glBindRenderbuffer");
    glDeleteRenderbuffers = (_glDeleteRenderbuffers) qt_gl_getProcAddressEXT(ctx, "glDeleteRenderbuffers");
    glGenRenderbuffers = (_glGenRenderbuffers) qt_gl_getProcAddressEXT(ctx, "glGenRenderbuffers");
    glRenderbufferStorage = (_glRenderbufferStorage) qt_gl_getProcAddressEXT(ctx, "glRenderbufferStorage");
    glGetRenderbufferParameteriv =
        (_glGetRenderbufferParameteriv) qt_gl_getProcAddressEXT(ctx, "glGetRenderbufferParameteriv");
    glIsFramebuffer = (_glIsFramebuffer) qt_gl_getProcAddressEXT(ctx, "glIsFramebuffer");
    glBindFramebuffer = (_glBindFramebuffer) qt_gl_getProcAddressEXT(ctx, "glBindFramebuffer");
    glDeleteFramebuffers = (_glDeleteFramebuffers) qt_gl_getProcAddressEXT(ctx, "glDeleteFramebuffers");
    glGenFramebuffers = (_glGenFramebuffers) qt_gl_getProcAddressEXT(ctx, "glGenFramebuffers");
    glCheckFramebufferStatus = (_glCheckFramebufferStatus) qt_gl_getProcAddressEXT(ctx, "glCheckFramebufferStatus");
    glFramebufferTexture2D = (_glFramebufferTexture2D) qt_gl_getProcAddressEXT(ctx, "glFramebufferTexture2D");
    glFramebufferRenderbuffer = (_glFramebufferRenderbuffer) qt_gl_getProcAddressEXT(ctx, "glFramebufferRenderbuffer");
    glGetFramebufferAttachmentParameteriv =
        (_glGetFramebufferAttachmentParameteriv) qt_gl_getProcAddressEXT(ctx, "glGetFramebufferAttachmentParameteriv");
    glGenerateMipmap = (_glGenerateMipmap) qt_gl_getProcAddressEXT(ctx, "glGenerateMipmap");

    return glIsRenderbuffer != 0;
#else
    return true;
#endif
}

#if !defined(QT_OPENGL_ES_2)
bool qt_resolve_version_1_3_functions(QGLContext *ctx)
{
    if (glMultiTexCoord4f != 0)
        return true;

    QGLContext cx(QGLFormat::defaultFormat());
    glMultiTexCoord4f = (_glMultiTexCoord4f) ctx->getProcAddress(QLatin1String("glMultiTexCoord4f"));

    glActiveTexture = (_glActiveTexture) ctx->getProcAddress(QLatin1String("glActiveTexture"));
    return glMultiTexCoord4f && glActiveTexture;
}
#endif

#if !defined(QT_OPENGL_ES_2)
bool qt_resolve_stencil_face_extension(QGLContext *ctx)
{
    if (glActiveStencilFaceEXT != 0)
        return true;

    QGLContext cx(QGLFormat::defaultFormat());
    glActiveStencilFaceEXT = (_glActiveStencilFaceEXT) ctx->getProcAddress(QLatin1String("glActiveStencilFaceEXT"));

    return glActiveStencilFaceEXT;
}
#endif


#if !defined(QT_OPENGL_ES_2)
bool qt_resolve_frag_program_extensions(QGLContext *ctx)
{
    if (glProgramStringARB != 0)
        return true;

    // ARB_fragment_program
    glProgramStringARB = (_glProgramStringARB) ctx->getProcAddress(QLatin1String("glProgramStringARB"));
    glBindProgramARB = (_glBindProgramARB) ctx->getProcAddress(QLatin1String("glBindProgramARB"));
    glDeleteProgramsARB = (_glDeleteProgramsARB) ctx->getProcAddress(QLatin1String("glDeleteProgramsARB"));
    glGenProgramsARB = (_glGenProgramsARB) ctx->getProcAddress(QLatin1String("glGenProgramsARB"));