eglfs: Move reusable functionality to eglconvenience

The cursor implementation is generic GL(ES) code that should be shared
by all the present and future egl-based embedded platform
plugins. Follow the pattern of QEGLPlatformContext and move this class
into eglconvenience as QEGLPlatformCursor.

Similarly, the common bits from the context implementation context are
moved back to EGLPlatformContext.

eglconvenience has now base classes for integration, screen, window,
etc. too. By using these, eglfs becomes much smaller and cleaner. This
also paves the way for creating new, separate EGL-based platform
plugins for Android, embedded Linux, etc.

Also added some documentation to each of the base classes.

devicediscovery is now fixed to be usable on any platform. The
implementation in this case is naturally a dummy one. This finally
allows using it from anywhere without myriads of ugly ifdefs.

Change-Id: I02946e360c04e02de7fe234a23a08320eff4ccf5
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>

1 files changed, 110 insertions, 0 deletions

diff --git a/src/platformsupport/eglconvenience/qeglplatformscreen.cpp b/src/platformsupport/eglconvenience/qeglplatformscreen.cpp
new file mode 100644
index 0000000000..72e7f6a6df
--- /dev/null
+++ b/src/platformsupport/eglconvenience/qeglplatformscreen.cpp
@@ -0,0 +1,110 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins 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 "qeglcompositor_p.h"
+#include "qeglplatformscreen_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QEGLPlatformScreen
+    \brief Base class for EGL-based platform screen implementations.
+    \since 5.2
+    \internal
+    \ingroup qpa
+
+    This class provides a lightweight base for QPlatformScreen
+    implementations. It covers basic window stack management which is
+    necessary when compositing multiple raster (widget-based) windows
+    together into one single native surface.
+
+    Reimplementing the virtuals are essential when using
+    QEGLPlatformBackingStore. The context and the window returned from
+    these are the ones that are used when compositing the textures
+    generated from the raster (widget) based windows.
+
+    \note It is up to the QEGLPlatformWindow subclasses to use the
+    functions, like addWindow(), removeWindow(), etc., provided here.
+ */
+
+QEGLPlatformScreen::QEGLPlatformScreen(EGLDisplay dpy)
+    : m_dpy(dpy)
+{
+}
+
+QEGLPlatformScreen::~QEGLPlatformScreen()
+{
+    QEGLCompositor::destroy();
+}
+
+void QEGLPlatformScreen::addWindow(QEGLPlatformWindow *window)
+{
+    if (!m_windows.contains(window)) {
+        m_windows.append(window);
+        topWindowChanged(window);
+    }
+}
+
+void QEGLPlatformScreen::removeWindow(QEGLPlatformWindow *window)
+{
+    m_windows.removeOne(window);
+    if (!m_windows.isEmpty())
+        topWindowChanged(m_windows.last());
+}
+
+void QEGLPlatformScreen::moveToTop(QEGLPlatformWindow *window)
+{
+    m_windows.removeOne(window);
+    m_windows.append(window);
+    topWindowChanged(window);
+}
+
+void QEGLPlatformScreen::changeWindowIndex(QEGLPlatformWindow *window, int newIdx)
+{
+    int idx = m_windows.indexOf(window);
+    if (idx != -1 && idx != newIdx) {
+        m_windows.move(idx, newIdx);
+        if (newIdx == m_windows.size() - 1)
+            topWindowChanged(m_windows.last());
+    }
+}
+
+QT_END_NAMESPACE