Add OpenGLInfo attached type

[ChangeLog][QtQuick] Introduced OpenGLInfo attached type that
provides information about the currently used OpenGL version.

Change-Id: Ibdf365decf9d6331cf91c0bf541e493ced02a417
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>

5 files changed, 330 insertions, 2 deletions

diff --git a/src/quick/items/items.pri b/src/quick/items/items.pri
index 87e2212dd3..0b98782566 100644
--- a/src/quick/items/items.pri
+++ b/src/quick/items/items.pri
@@ -78,7 +78,8 @@ HEADERS += \
     $$PWD/qquickframebufferobject.h \
     $$PWD/qquickitemgrabresult.h \
     $$PWD/qquickrendercontrol.h \
-    $$PWD/qquickrendercontrol_p.h
+    $$PWD/qquickrendercontrol_p.h \
+    $$PWD/qquickopenglinfo_p.h
 
 SOURCES += \
     $$PWD/qquickevents.cpp \
@@ -133,7 +134,8 @@ SOURCES += \
     $$PWD/qquickwindowattached.cpp \
     $$PWD/qquickframebufferobject.cpp \
     $$PWD/qquickitemgrabresult.cpp \
-    $$PWD/qquickrendercontrol.cpp
+    $$PWD/qquickrendercontrol.cpp \
+    $$PWD/qquickopenglinfo.cpp
 
 SOURCES += \
     $$PWD/qquickshadereffect.cpp \
diff --git a/src/quick/items/qquickitemsmodule.cpp b/src/quick/items/qquickitemsmodule.cpp
index d8671390af..b325158165 100644
--- a/src/quick/items/qquickitemsmodule.cpp
+++ b/src/quick/items/qquickitemsmodule.cpp
@@ -83,6 +83,7 @@
 #include "qquickdrag_p.h"
 #include "qquickdroparea_p.h"
 #include "qquickmultipointtoucharea_p.h"
+#include "qquickopenglinfo_p.h"
 #include <private/qqmlmetatype_p.h>
 #include <QtQuick/private/qquickaccessibleattached_p.h>
 
@@ -273,6 +274,7 @@ static void qt_quickitems_defineModule(const char *uri, int major, int minor)
     qmlRegisterType<QQuickListView, 2>(uri, 2, 4, "ListView");
     qmlRegisterType<QQuickMouseArea, 1>(uri, 2, 4, "MouseArea");
     qmlRegisterType<QQuickShaderEffect, 1>(uri, 2, 4, "ShaderEffect");
+    qmlRegisterUncreatableType<QQuickOpenGLInfo>(uri, 2, 4,"OpenGLInfo", QQuickOpenGLInfo::tr("OpenGLInfo is only available via attached properties"));
 }
 
 static void initResources()
diff --git a/src/quick/items/qquickopenglinfo.cpp b/src/quick/items/qquickopenglinfo.cpp
new file mode 100644
index 0000000000..dbaa92abe1
--- /dev/null
+++ b/src/quick/items/qquickopenglinfo.cpp
@@ -0,0 +1,200 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 BlackBerry Ltd.
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** 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, Digia gives you certain additional
+** rights.  These rights are described in the Digia 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qquickopenglinfo_p.h"
+#include "qopenglcontext.h"
+#include "qquickwindow.h"
+#include "qquickitem.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmltype OpenGLInfo
+    \instantiates QQuickOpenGLInfo
+    \inqmlmodule QtQuick
+    \ingroup qtquick-effects
+    \since 5.4
+    \brief Provides information about the used OpenGL version
+
+    The OpenGLInfo attached type provides information about the OpenGL
+    version being used to render the surface of the attachee item.
+
+    If the attachee item is not currently associated with any graphical
+    surface, the properties are set to the values of the default surface
+    format. When it becomes associated with a surface, all properties
+    will update.
+
+    \sa ShaderEffect
+ */
+QQuickOpenGLInfo::QQuickOpenGLInfo(QQuickItem *item)
+    : QObject(item)
+    , m_window(0)
+    , m_majorVersion(2)
+    , m_minorVersion(0)
+    , m_profile(NoProfile)
+    , m_renderableType(Unspecified)
+{
+    connect(item, SIGNAL(windowChanged(QQuickWindow*)), this, SLOT(setWindow(QQuickWindow*)));
+    setWindow(item->window());
+}
+
+/*!
+    \qmlproperty int QtQuick::OpenGLInfo::majorVersion
+
+    This property holds the major OpenGL version.
+
+    The default version is \c 2.0.
+
+    \sa minorVersion, profile
+ */
+int QQuickOpenGLInfo::majorVersion() const
+{
+    return m_majorVersion;
+}
+
+/*!
+    \qmlproperty int QtQuick::OpenGLInfo::minorVersion
+
+    This property holds the minor OpenGL version.
+
+    The default version is \c 2.0.
+
+    \sa majorVersion, profile
+ */
+int QQuickOpenGLInfo::minorVersion() const
+{
+    return m_minorVersion;
+}
+
+/*!
+    \qmlproperty enumeration QtQuick::OpenGLInfo::profile
+
+    This property holds the configured OpenGL context profile.
+
+    The possible values are:
+    \list
+    \li OpenGLInfo.NoProfile (default) - OpenGL version is lower than 3.2.
+    \li OpenGLInfo.CoreProfile - Functionality deprecated in OpenGL version 3.0 is not available.
+    \li OpenGLInfo.CompatibilityProfile - Functionality from earlier OpenGL versions is available.
+    \endlist
+
+    Reusable QML components will typically use this property in bindings in order to
+    choose between core and non core profile compatible shader sources.
+
+    \sa majorVersion, minorVersion
+ */
+QQuickOpenGLInfo::ContextProfile QQuickOpenGLInfo::profile() const
+{
+    return m_profile;
+}
+
+/*!
+    \qmlproperty enumeration QtQuick::OpenGLInfo::renderableType
+
+    This property holds the renderable type.
+
+    The possible values are:
+    \list
+    \li OpenGLInfo.Unspecified (default) - Unspecified rendering method
+    \li OpenGLInfo.OpenGL - Desktop OpenGL rendering
+    \li OpenGLInfo.OpenGLES - OpenGL ES rendering
+    \endlist
+ */
+QQuickOpenGLInfo::RenderableType QQuickOpenGLInfo::renderableType() const
+{
+    return m_renderableType;
+}
+
+QQuickOpenGLInfo *QQuickOpenGLInfo::qmlAttachedProperties(QObject *object)
+{
+    if (QQuickItem *item = qobject_cast<QQuickItem *>(object))
+        return new QQuickOpenGLInfo(item);
+    return 0;
+}
+
+void QQuickOpenGLInfo::updateFormat()
+{
+    QOpenGLContext *context = 0;
+    if (m_window)
+        context = m_window->openglContext();
+    QSurfaceFormat format = context ? context->format() : QSurfaceFormat::defaultFormat();
+
+    if (m_majorVersion != format.majorVersion()) {
+        m_majorVersion = format.majorVersion();
+        emit majorVersionChanged();
+    }
+
+    if (m_minorVersion != format.minorVersion()) {
+        m_minorVersion = format.minorVersion();
+        emit minorVersionChanged();
+    }
+
+    ContextProfile profile = static_cast<ContextProfile>(format.profile());
+    if (m_profile != profile) {
+        m_profile = profile;
+        emit profileChanged();
+    }
+
+    RenderableType renderableType = static_cast<RenderableType>(format.renderableType());
+    if (m_renderableType != renderableType) {
+        m_renderableType = renderableType;
+        emit renderableTypeChanged();
+    }
+}
+
+void QQuickOpenGLInfo::setWindow(QQuickWindow *window)
+{
+    if (m_window != window) {
+        if (m_window) {
+            disconnect(m_window, SIGNAL(sceneGraphInitialized()), this, SLOT(updateFormat()));
+            disconnect(m_window, SIGNAL(sceneGraphInvalidated()), this, SLOT(updateFormat()));
+        }
+        if (window) {
+            connect(window, SIGNAL(sceneGraphInitialized()), this, SLOT(updateFormat()));
+            connect(window, SIGNAL(sceneGraphInvalidated()), this, SLOT(updateFormat()));
+        }
+        m_window = window;
+    }
+    updateFormat();
+}
+
+QT_END_NAMESPACE
diff --git a/src/quick/items/qquickopenglinfo_p.h b/src/quick/items/qquickopenglinfo_p.h
new file mode 100644
index 0000000000..70684a2f40
--- /dev/null
+++ b/src/quick/items/qquickopenglinfo_p.h
@@ -0,0 +1,122 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 BlackBerry Ltd.
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** 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, Digia gives you certain additional
+** rights.  These rights are described in the Digia 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQUICKOPENGLINFO_P_H
+#define QQUICKOPENGLINFO_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qobject.h>
+#include <QtCore/qpointer.h>
+#include <QtGui/qsurfaceformat.h>
+#include <QtQml/qqml.h>
+
+QT_BEGIN_NAMESPACE
+
+class QQuickItem;
+class QQuickWindow;
+
+class QQuickOpenGLInfo : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(int majorVersion READ majorVersion NOTIFY majorVersionChanged FINAL)
+    Q_PROPERTY(int minorVersion READ minorVersion NOTIFY minorVersionChanged FINAL)
+    Q_PROPERTY(ContextProfile profile READ profile NOTIFY profileChanged FINAL)
+    Q_PROPERTY(RenderableType renderableType READ renderableType NOTIFY renderableTypeChanged FINAL)
+    Q_ENUMS(ContextProfile RenderableType)
+
+public:
+    QQuickOpenGLInfo(QQuickItem *item = 0);
+
+    int majorVersion() const;
+    int minorVersion() const;
+
+    // keep in sync with QSurfaceFormat::OpenGLContextProfile
+    enum ContextProfile {
+        NoProfile = QSurfaceFormat::NoProfile,
+        CoreProfile = QSurfaceFormat::CoreProfile,
+        CompatibilityProfile = QSurfaceFormat::CompatibilityProfile
+    };
+    ContextProfile profile() const;
+
+    // keep in sync with QSurfaceFormat::RenderableType
+    enum RenderableType {
+        Unspecified = QSurfaceFormat::DefaultRenderableType,
+        OpenGL = QSurfaceFormat::OpenGL,
+        OpenGLES = QSurfaceFormat::OpenGLES
+    };
+    RenderableType renderableType() const;
+
+    static QQuickOpenGLInfo *qmlAttachedProperties(QObject *object);
+
+Q_SIGNALS:
+    void majorVersionChanged();
+    void minorVersionChanged();
+    void profileChanged();
+    void renderableTypeChanged();
+
+private Q_SLOTS:
+    void updateFormat();
+    void setWindow(QQuickWindow *window);
+
+private:
+    QPointer<QQuickWindow> m_window;
+    int m_majorVersion;
+    int m_minorVersion;
+    ContextProfile m_profile;
+    RenderableType m_renderableType;
+};
+
+QT_END_NAMESPACE
+
+QML_DECLARE_TYPEINFO(QQuickOpenGLInfo, QML_HAS_ATTACHED_PROPERTIES)
+
+#endif // QQUICKOPENGLINFO_P_H
diff --git a/src/quick/items/qquickshadereffect.cpp b/src/quick/items/qquickshadereffect.cpp
index 9dfce3fb28..148c33d2cd 100644
--- a/src/quick/items/qquickshadereffect.cpp
+++ b/src/quick/items/qquickshadereffect.cpp
@@ -651,6 +651,8 @@ void QQuickShaderEffectCommon::propertyChanged(QQuickItem *item, int mappedId,
 
     \note Scene Graph textures have origin in the top-left corner rather than
     bottom-left which is common in OpenGL.
+
+    For information about the GLSL version being used, see \l QtQuick::OpenGLInfo.
 */
 
 QQuickShaderEffect::QQuickShaderEffect(QQuickItem *parent)