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// Copyright (C) 2013 Klaralvdalens Datakonsult AB (KDAB)
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
/***************************************************************************
** This file was generated by glgen version 0.1
** Command line was: glgen
**
** glgen is Copyright (C) 2013 Klaralvdalens Datakonsult AB (KDAB)
**
** This is an auto-generated file.
** Do not edit! All changes made to it will be lost.
**
****************************************************************************/
#include "qopenglversionfunctions.h"
#include "qopenglcontext.h"
#include "qdebug.h"
QT_BEGIN_NAMESPACE
QOpenGLVersionFunctionsBackend *QAbstractOpenGLFunctionsPrivate::functionsBackend(QOpenGLContext *context,
const QOpenGLVersionStatus &v)
{
Q_ASSERT(context);
return context->functionsBackend(v);
}
void QAbstractOpenGLFunctionsPrivate::insertFunctionsBackend(QOpenGLContext *context,
const QOpenGLVersionStatus &v,
QOpenGLVersionFunctionsBackend *backend)
{
Q_ASSERT(context);
context->insertFunctionsBackend(v, backend);
}
void QAbstractOpenGLFunctionsPrivate::removeFunctionsBackend(QOpenGLContext *context, const QOpenGLVersionStatus &v)
{
Q_ASSERT(context);
context->removeFunctionsBackend(v);
}
/*!
\class QAbstractOpenGLFunctions
\inmodule QtGui
\since 5.1
\brief The QAbstractOpenGLFunctions class is the base class of a family of
classes that expose all functions for each OpenGL version and
profile.
OpenGL implementations on different platforms are able to link to a variable
number of OpenGL functions depending upon the OpenGL ABI on that platform.
For example, on Microsoft Windows only functions up to those in OpenGL 1.1
can be linked to at build time. All other functions must be resolved at
runtime. The traditional solution to this has been to use either
QOpenGLContext::getProcAddress() or QOpenGLFunctions. The former is tedious
and error prone and means dealing directly with function pointers. The
latter only exposes those functions common to OpenGL ES 2 and desktop
OpenGL. There is however much new OpenGL functionality that is useful when
writing real world OpenGL applications.
Qt now provides a family of classes which all inherit from
QAbstractOpenGLFunctions which expose every core OpenGL function by way of a
corresponding member function. There is a class for every valid combination
of OpenGL version and profile. Each class follows the naming convention
QOpenGLFunctions_<MAJOR VERSION>_<MINOR VERSION>[_PROFILE].
For OpenGL versions 1.0 through to 3.0 there are no profiles, leading to the
classes:
\list
\li QOpenGLFunctions_1_0
\li QOpenGLFunctions_1_1
\li QOpenGLFunctions_1_2
\li QOpenGLFunctions_1_3
\li QOpenGLFunctions_1_4
\li QOpenGLFunctions_1_5
\li QOpenGLFunctions_2_0
\li QOpenGLFunctions_2_1
\li QOpenGLFunctions_3_0
\endlist
where each class inherits from QAbstractOpenGLFunctions.
OpenGL version 3.1 removed many deprecated functions leading to a much
simpler and generic API.
With OpenGL 3.2 the concept of profiles was introduced. Two profiles are
currently defined for OpenGL: Core and Compatibility.
The Core profile does not include any of the functions that were removed
in OpenGL 3.1. The Compatibility profile contains all functions in the
Core profile of the same version plus all of the functions that were
removed in OpenGL 3.1. In this way the Compatibility profile classes allow
use of newer OpenGL functionality but also allows you to keep using your
legacy OpenGL code. For new OpenGL code the Core profile should be
preferred.
Please note that some vendors, notably Apple, do not implement the
Compatibility profile. Therefore if you wish to target new OpenGL features
on OS X then you should ensure that you request a Core profile context via
QSurfaceFormat::setProfile().
Qt provides classes for all version and Core and Compatibility profile
combinations. The classes for OpenGL versions 3.1 through to 4.3 are:
\list
\li QOpenGLFunctions_3_1
\li QOpenGLFunctions_3_2_Core
\li QOpenGLFunctions_3_2_Compatibility
\li QOpenGLFunctions_3_3_Core
\li QOpenGLFunctions_3_3_Compatibility
\li QOpenGLFunctions_4_0_Core
\li QOpenGLFunctions_4_0_Compatibility
\li QOpenGLFunctions_4_1_Core
\li QOpenGLFunctions_4_1_Compatibility
\li QOpenGLFunctions_4_2_Core
\li QOpenGLFunctions_4_2_Compatibility
\li QOpenGLFunctions_4_3_Core
\li QOpenGLFunctions_4_3_Compatibility
\endlist
where each class inherits from QAbstractOpenGLFunctions.
A pointer to an object of the class corresponding to the version and
profile of OpenGL in use can be obtained from
QOpenGLFunctions::versionFunctions(). If obtained in this way, note that
the QOpenGLContext retains ownership of the object. This is so that only
one instance need be created.
Before calling any of the exposed OpenGL functions you must ensure that the
object has resolved the function pointers to the OpenGL functions. This
only needs to be done once per instance with initializeOpenGLFunctions().
Once initialized, the object can be used to call any OpenGL function for
the corresponding version and profile. Note that initializeOpenGLFunctions()
can fail in some circumstances so check the return value. Situations in
which initialization can fail are if you have a functions object for a version
or profile that contains functions that are not part of the context being
used to resolve the function pointers.
If you exclusively use function objects then you will get compile time
errors if you attempt to use a function not included in that version and
profile. This is obviously a lot easier to debug than undefined behavior
at run time.
\sa QOpenGLContext::versionFunctions()
*/
QAbstractOpenGLFunctions::QAbstractOpenGLFunctions()
: d_ptr(new QAbstractOpenGLFunctionsPrivate)
{
}
QAbstractOpenGLFunctions::~QAbstractOpenGLFunctions()
{
delete d_ptr;
}
bool QAbstractOpenGLFunctions::initializeOpenGLFunctions()
{
Q_D(QAbstractOpenGLFunctions);
d->initialized = true;
return true;
}
bool QAbstractOpenGLFunctions::isInitialized() const
{
Q_D(const QAbstractOpenGLFunctions);
return d->initialized;
}
void QAbstractOpenGLFunctions::setOwningContext(const QOpenGLContext *context)
{
Q_D(QAbstractOpenGLFunctions);
d->owningContext = const_cast<QOpenGLContext*>(context);
}
QOpenGLContext *QAbstractOpenGLFunctions::owningContext() const
{
Q_D(const QAbstractOpenGLFunctions);
return d->owningContext;
}
#if !QT_CONFIG(opengles2)
