/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtOpenGL module of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** 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.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

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**

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**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#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"));

    glProgramLocalParameter4fvARB = (_glProgramLocalParameter4fvARB) ctx->getProcAddress(QLatin1String("glProgramLocalParameter4fvARB"));

    return glProgramStringARB

        && glBindProgramARB

        && glDeleteProgramsARB

        && glGenProgramsARB

        && glProgramLocalParameter4fvARB;

}

#endif

bool qt_resolve_buffer_extensions(QGLContext *ctx)

{

    if (glMapBufferARB && glUnmapBufferARB

#if !defined(QT_OPENGL_ES_2)

        && glBindBuffer && glDeleteBuffers && glGenBuffers && glBufferData

#endif

        )

        return true;

#if !defined(QT_OPENGL_ES_2)

    glBindBuffer = (_glBindBuffer) qt_gl_getProcAddressARB(ctx, "glBindBuffer");

    glDeleteBuffers = (_glDeleteBuffers) qt_gl_getProcAddressARB(ctx, "glDeleteBuffers");

    glGenBuffers = (_glGenBuffers) qt_gl_getProcAddressARB(ctx, "glGenBuffers");

    glBufferData = (_glBufferData) qt_gl_getProcAddressARB(ctx, "glBufferData");

#endif

    glMapBufferARB = (_glMapBufferARB) qt_gl_getProcAddressARB(ctx, "glMapBuffer");

    glUnmapBufferARB = (_glUnmapBufferARB) qt_gl_getProcAddressARB(ctx, "glUnmapBuffer");

    return glMapBufferARB

        && glUnmapBufferARB

#if !defined(QT_OPENGL_ES_2)

        && glBindBuffer

        && glDeleteBuffers

        && glGenBuffers

        && glBufferData

#endif

        ;

}

bool qt_resolve_glsl_extensions(QGLContext *ctx)

{

#if defined(QT_OPENGL_ES_2)

    // The GLSL shader functions are always present in OpenGL/ES 2.0.

    // The only exceptions are glGetProgramBinaryOES and glProgramBinaryOES.

    if (!QGLContextPrivate::extensionFuncs(ctx).qt_glslResolved) {

        glGetProgramBinaryOES = (_glGetProgramBinaryOES) ctx->getProcAddress(QLatin1String("glGetProgramBinaryOES"));

        glProgramBinaryOES = (_glProgramBinaryOES) ctx->getProcAddress(QLatin1String("glProgramBinaryOES"));

        QGLContextPrivate::extensionFuncs(ctx).qt_glslResolved = true;

    }

    return true;

#else

    if (glCreateShader)

        return true;

    glCreateShader = (_glCreateShader) ctx->getProcAddress(QLatin1String("glCreateShader"));

    if (glCreateShader) {

        glShaderSource = (_glShaderSource) ctx->getProcAddress(QLatin1String("glShaderSource"));

        glShaderBinary = (_glShaderBinary) ctx->getProcAddress(QLatin1String("glShaderBinary"));

        glCompileShader = (_glCompileShader) ctx->getProcAddress(QLatin1String("glCompileShader"));

        glDeleteShader = (_glDeleteShader) ctx->getProcAddress(QLatin1String("glDeleteShader"));

        glIsShader = (_glIsShader) ctx->getProcAddress(QLatin1String("glIsShader"));

        glCreateProgram = (_glCreateProgram) ctx->getProcAddress(QLatin1String("glCreateProgram"));

        glAttachShader = (_glAttachShader) ctx->getProcAddress(QLatin1String("glAttachShader"));

        glDetachShader = (_glDetachShader) ctx->getProcAddress(QLatin1String("glDetachShader"));

        glLinkProgram = (_glLinkProgram) ctx->getProcAddress(QLatin1String("glLinkProgram"));

        glUseProgram = (_glUseProgram) ctx->getProcAddress(QLatin1String("glUseProgram"));

        glDeleteProgram = (_glDeleteProgram) ctx->getProcAddress(QLatin1String("glDeleteProgram"));

        glIsProgram = (_glIsProgram) ctx->getProcAddress(QLatin1String("glIsProgram"));

        glGetShaderInfoLog = (_glGetShaderInfoLog) ctx->getProcAddress(QLatin1String("glGetShaderInfoLog"));

        glGetShaderiv = (_glGetShaderiv) ctx->getProcAddress(QLatin1String("glGetShaderiv"));

        glGetShaderSource = (_glGetShaderSource) ctx->getProcAddress(QLatin1String("glGetShaderSource"));

        glGetProgramiv = (_glGetProgramiv) ctx->getProcAddress(QLatin1String("glGetProgramiv"));

        glGetProgramInfoLog = (_glGetProgramInfoLog) ctx->getProcAddress(QLatin1String("glGetProgramInfoLog"));

        glGetUniformLocation = (_glGetUniformLocation) ctx->getProcAddress(QLatin1String("glGetUniformLocation"));

        glUniform4fv = (_glUniform4fv) ctx->getProcAddress(QLatin1String("glUniform4fv"));

        glUniform3fv = (_glUniform3fv) ctx->getProcAddress(QLatin1String("glUniform3fv"));

        glUniform2fv = (_glUniform2fv) ctx->getProcAddress(QLatin1String("glUniform2fv"));

        glUniform1fv = (_glUniform1fv) ctx->getProcAddress(QLatin1String("glUniform1fv"));

        glUniform1i = (_glUniform1i) ctx->getProcAddress(QLatin1String("glUniform1i"));

        glUniform1iv = (_glUniform1iv) ctx->getProcAddress(QLatin1String("glUniform1iv"));

        glUniformMatrix2fv = (_glUniformMatrix2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2fv"));

        glUniformMatrix3fv = (_glUniformMatrix3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3fv"));

        glUniformMatrix4fv = (_glUniformMatrix4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4fv"));

        glUniformMatrix2x3fv = (_glUniformMatrix2x3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2x3fv"));

        glUniformMatrix2x4fv = (_glUniformMatrix2x4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2x4fv"));

        glUniformMatrix3x2fv = (_glUniformMatrix3x2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3x2fv"));

        glUniformMatrix3x4fv = (_glUniformMatrix3x4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3x4fv"));

        glUniformMatrix4x2fv = (_glUniformMatrix4x2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4x2fv"));

        glUniformMatrix4x3fv = (_glUniformMatrix4x3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4x3fv"));

        glBindAttribLocation = (_glBindAttribLocation) ctx->getProcAddress(QLatin1String("glBindAttribLocation"));

        glGetAttribLocation = (_glGetAttribLocation) ctx->getProcAddress(QLatin1String("glGetAttribLocation"));

        glVertexAttrib1fv = (_glVertexAttrib1fv) ctx->getProcAddress(QLatin1String("glVertexAttrib1fv"));

        glVertexAttrib2fv = (_glVertexAttrib2fv) ctx->getProcAddress(QLatin1String("glVertexAttrib2fv"));

        glVertexAttrib3fv = (_glVertexAttrib3fv) ctx->getProcAddress(QLatin1String("glVertexAttrib3fv"));

        glVertexAttrib4fv = (_glVertexAttrib4fv) ctx->getProcAddress(QLatin1String("glVertexAttrib4fv"));

        glVertexAttribPointer = (_glVertexAttribPointer) ctx->getProcAddress(QLatin1String("glVertexAttribPointer"));

        glDisableVertexAttribArray = (_glDisableVertexAttribArray) ctx->getProcAddress(QLatin1String("glDisableVertexAttribArray"));

        glEnableVertexAttribArray = (_glEnableVertexAttribArray) ctx->getProcAddress(QLatin1String("glEnableVertexAttribArray"));

    } else {

        // We may not have the standard shader functions, but we might

        // have the older ARB functions instead.

        glCreateShader = (_glCreateShader) ctx->getProcAddress(QLatin1String("glCreateShaderObjectARB"));

        glShaderSource = (_glShaderSource) ctx->getProcAddress(QLatin1String("glShaderSourceARB"));

        glShaderBinary = (_glShaderBinary) ctx->getProcAddress(QLatin1String("glShaderBinaryARB"));

        glCompileShader = (_glCompileShader) ctx->getProcAddress(QLatin1String("glCompileShaderARB"));

        glDeleteShader = (_glDeleteShader) ctx->getProcAddress(QLatin1String("glDeleteObjectARB"));

        glIsShader = 0;

        glCreateProgram = (_glCreateProgram) ctx->getProcAddress(QLatin1String("glCreateProgramObjectARB"));

        glAttachShader = (_glAttachShader) ctx->getProcAddress(QLatin1String("glAttachObjectARB"));

        glDetachShader = (_glDetachShader) ctx->getProcAddress(QLatin1String("glDetachObjectARB"));

        glLinkProgram = (_glLinkProgram) ctx->getProcAddress(QLatin1String("glLinkProgramARB"));

        glUseProgram = (_glUseProgram) ctx->getProcAddress(QLatin1String("glUseProgramObjectARB"));

        glDeleteProgram = (_glDeleteProgram) ctx->getProcAddress(QLatin1String("glDeleteObjectARB"));

        glIsProgram = 0;

        glGetShaderInfoLog = (_glGetShaderInfoLog) ctx->getProcAddress(QLatin1String("glGetInfoLogARB"));

        glGetShaderiv = (_glGetShaderiv) ctx->getProcAddress(QLatin1String("glGetObjectParameterivARB"));

        glGetShaderSource = (_glGetShaderSource) ctx->getProcAddress(QLatin1String("glGetShaderSourceARB"));

        glGetProgramiv = (_glGetProgramiv) ctx->getProcAddress(QLatin1String("glGetObjectParameterivARB"));

        glGetProgramInfoLog = (_glGetProgramInfoLog) ctx->getProcAddress(QLatin1String("glGetInfoLogARB"));

        glGetUniformLocation = (_glGetUniformLocation) ctx->getProcAddress(QLatin1String("glGetUniformLocationARB"));

        glUniform4fv = (_glUniform4fv) ctx->getProcAddress(QLatin1String("glUniform4fvARB"));

        glUniform3fv = (_glUniform3fv) ctx->getProcAddress(QLatin1String("glUniform3fvARB"));

        glUniform2fv = (_glUniform2fv) ctx->getProcAddress(QLatin1String("glUniform2fvARB"));

        glUniform1fv = (_glUniform1fv) ctx->getProcAddress(QLatin1String("glUniform1fvARB"));

        glUniform1i = (_glUniform1i) ctx->getProcAddress(QLatin1String("glUniform1iARB"));

        glUniform1iv = (_glUniform1iv) ctx->getProcAddress(QLatin1String("glUniform1ivARB"));

        glUniformMatrix2fv = (_glUniformMatrix2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2fvARB"));

        glUniformMatrix3fv = (_glUniformMatrix3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3fvARB"));

        glUniformMatrix4fv = (_glUniformMatrix4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4fvARB"));

        glUniformMatrix2x3fv = (_glUniformMatrix2x3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2x3fvARB"));

        glUniformMatrix2x4fv = (_glUniformMatrix2x4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix2x4fvARB"));

        glUniformMatrix3x2fv = (_glUniformMatrix3x2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3x2fvARB"));

        glUniformMatrix3x4fv = (_glUniformMatrix3x4fv) ctx->getProcAddress(QLatin1String("glUniformMatrix3x4fvARB"));

        glUniformMatrix4x2fv = (_glUniformMatrix4x2fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4x2fvARB"));

        glUniformMatrix4x3fv = (_glUniformMatrix4x3fv) ctx->getProcAddress(QLatin1String("glUniformMatrix4x3fvARB"));

        glBindAttribLocation = (_glBindAttribLocation) ctx->getProcAddress(QLatin1String("glBindAttribLocationARB"));

        glGetAttribLocation = (_glGetAttribLocation) ctx->getProcAddress(QLatin1String("glGetAttribLocationARB"));

        glVertexAttrib1fv = (_glVertexAttrib1fv) ctx->getProcAddress(QLatin1String("glVertexAttrib1fvARB"));

        glVertexAttrib2fv = (_glVertexAttrib2fv) ctx->getProcAddress(QLatin1String("glVertexAttrib2fvARB"));

        glVertexAttrib3fv = (_glVertexAttrib3fv) ctx->getProcAddress(QLatin1String("glVertexAttrib3fvARB"));

        glVertexAttrib4fv = (_glVertexAttrib4fv) ctx->getProcAddress(QLatin1String("glVertexAttrib4fvARB"));

        glVertexAttribPointer = (_glVertexAttribPointer) ctx->getProcAddress(QLatin1String("glVertexAttribPointerARB"));

        glDisableVertexAttribArray = (_glDisableVertexAttribArray) ctx->getProcAddress(QLatin1String("glDisableVertexAttribArrayARB"));

        glEnableVertexAttribArray = (_glEnableVertexAttribArray) ctx->getProcAddress(QLatin1String("glEnableVertexAttribArrayARB"));

    }

    // Note: glShaderBinary(), glIsShader(), glIsProgram(), and

    // glUniformMatrixNxMfv() are optional, but all other functions

    // are required.

    return glCreateShader &&

        glShaderSource &&

        glCompileShader &&

        glDeleteProgram &&

        glCreateProgram &&

        glAttachShader &&

        glDetachShader &&

        glLinkProgram &&

        glUseProgram &&

        glDeleteProgram &&

        glGetShaderInfoLog &&

        glGetShaderiv &&

        glGetShaderSource &&

        glGetProgramiv &&

        glGetProgramInfoLog &&

        glGetUniformLocation &&

        glUniform1fv &&

        glUniform2fv &&

        glUniform3fv &&

        glUniform4fv &&

        glUniform1i &&

        glUniform1iv &&

        glUniformMatrix2fv &&

        glUniformMatrix3fv &&

        glUniformMatrix4fv &&

        glBindAttribLocation &&

        glGetAttribLocation &&

        glVertexAttrib1fv &&

        glVertexAttrib2fv &&

        glVertexAttrib3fv &&

        glVertexAttrib4fv &&

        glVertexAttribPointer &&

        glDisableVertexAttribArray &&

        glEnableVertexAttribArray;

#endif

}

#if !defined(QT_OPENGL_ES_2)

bool qt_resolve_version_2_0_functions(QGLContext *ctx)

{

    bool gl2supported = true;

    if (!qt_resolve_glsl_extensions(ctx))

        gl2supported = false;

    if (!qt_resolve_version_1_3_functions(ctx))

        gl2supported = false;

    if (!qt_resolve_framebufferobject_extensions(ctx))

        gl2supported = false;

    if (glStencilOpSeparate)

        return gl2supported;

    glBlendColor = (_glBlendColor) ctx->getProcAddress(QLatin1String("glBlendColor"));

    glStencilOpSeparate = (_glStencilOpSeparate) ctx->getProcAddress(QLatin1String("glStencilOpSeparate"));

    if (!glBlendColor || !glStencilOpSeparate)

        gl2supported = false;

    return gl2supported;

}

#endif

QT_END_NAMESPACE