Make GLX and EGL dynamic dependencies for xcb

[ChangeLog][QPA][Xcb] GLX and EGL code paths are now dynamically
resolved, making it possible for one build of a plugin to use both code
paths. Default is to use the GLX code path if available. This can be
overwritten by specifying QT_XCB_GL_INTEGRATION=xcb_egl as an
evnironment variable. Enable qt.xcb.glintegration.debug to get debug log
output of what integration is used

Change-Id: Ia9fa95fcca3d901b91dadb8c98a695fea0ae3b1e
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>

1 files changed, 104 insertions, 0 deletions

diff --git a/src/plugins/platforms/xcb/gl_integrations/xcb_egl/qxcbeglcontext.h b/src/plugins/platforms/xcb/gl_integrations/xcb_egl/qxcbeglcontext.h
new file mode 100644
index 0000000000..0dce728019
--- /dev/null
+++ b/src/plugins/platforms/xcb/gl_integrations/xcb_egl/qxcbeglcontext.h
@@ -0,0 +1,104 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QXCBEGLCONTEXT_H
+#define QXCBEGLCONTEXT_H
+
+#include "qxcbeglwindow.h"
+#include <QtPlatformSupport/private/qeglplatformcontext_p.h>
+#include <QtPlatformSupport/private/qeglpbuffer_p.h>
+#include <QtPlatformHeaders/QEGLNativeContext>
+
+QT_BEGIN_NAMESPACE
+
+//####todo remove the noops (looks like their where there in the initial commit)
+class QXcbEglContext : public QEGLPlatformContext
+{
+public:
+    QXcbEglContext(const QSurfaceFormat &glFormat, QPlatformOpenGLContext *share,
+                           EGLDisplay display, QXcbConnection *c, const QVariant &nativeHandle)
+        : QEGLPlatformContext(glFormat, share, display, 0, nativeHandle)
+        , m_connection(c)
+    {
+        Q_XCB_NOOP(m_connection);
+    }
+
+    void swapBuffers(QPlatformSurface *surface)
+    {
+        Q_XCB_NOOP(m_connection);
+        QEGLPlatformContext::swapBuffers(surface);
+        Q_XCB_NOOP(m_connection);
+    }
+
+    bool makeCurrent(QPlatformSurface *surface)
+    {
+        Q_XCB_NOOP(m_connection);
+        bool ret = QEGLPlatformContext::makeCurrent(surface);
+        Q_XCB_NOOP(m_connection);
+        return ret;
+    }
+
+    void doneCurrent()
+    {
+        Q_XCB_NOOP(m_connection);
+        QEGLPlatformContext::doneCurrent();
+        Q_XCB_NOOP(m_connection);
+    }
+
+    EGLSurface eglSurfaceForPlatformSurface(QPlatformSurface *surface)
+    {
+        if (surface->surface()->surfaceClass() == QSurface::Window)
+            return static_cast<QXcbEglWindow *>(surface)->eglSurface();
+        else
+            return static_cast<QEGLPbuffer *>(surface)->pbuffer();
+    }
+
+    QVariant nativeHandle() const {
+        return QVariant::fromValue<QEGLNativeContext>(QEGLNativeContext(eglContext(), eglDisplay()));
+    }
+
+private:
+    QXcbConnection *m_connection;
+};
+
+QT_END_NAMESPACE
+#endif //QXCBEGLCONTEXT_H
+