Move eglconvenience to QtGui

Task-number: QTBUG-83255
Change-Id: I8a008d8906308dd73a0793db5b88d3a1b6fdaf5c
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 108 insertions, 0 deletions

diff --git a/src/gui/opengl/platform/egl/qeglpbuffer.cpp b/src/gui/opengl/platform/egl/qeglpbuffer.cpp
new file mode 100644
index 0000000000..55e199a6ad
--- /dev/null
+++ b/src/gui/opengl/platform/egl/qeglpbuffer.cpp
@@ -0,0 +1,108 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui/qoffscreensurface.h>
+#include "qeglpbuffer_p.h"
+#include "qeglconvenience_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QEGLPbuffer
+    \brief A pbuffer-based implementation of QPlatformOffscreenSurface for EGL.
+    \since 5.2
+    \internal
+    \ingroup qpa
+
+    To use this implementation in the platform plugin simply
+    reimplement QPlatformIntegration::createPlatformOffscreenSurface()
+    and return a new instance of this class.
+*/
+
+QEGLPbuffer::QEGLPbuffer(EGLDisplay display, const QSurfaceFormat &format, QOffscreenSurface *offscreenSurface,
+                         QEGLPlatformContext::Flags flags)
+    : QPlatformOffscreenSurface(offscreenSurface)
+    , m_format(format)
+    , m_display(display)
+    , m_pbuffer(EGL_NO_SURFACE)
+{
+    m_hasSurfaceless = !flags.testFlag(QEGLPlatformContext::NoSurfaceless)
+        && q_hasEglExtension(display, "EGL_KHR_surfaceless_context");
+
+    // Disable surfaceless contexts on Mesa for now. As of 10.6.0 and Intel at least, some
+    // operations (glReadPixels) are unable to work without a surface since they at some
+    // point temporarily unbind the current FBO and then later blow up in some seemingly
+    // safe operations, like setting the viewport, that apparently need access to the
+    // read/draw surface in the Intel backend.
+    const char *vendor = eglQueryString(display, EGL_VENDOR); // hard to check for GL_ strings here, so blacklist all Mesa
+    if (vendor && strstr(vendor, "Mesa"))
+        m_hasSurfaceless = false;
+
+    if (m_hasSurfaceless)
+        return;
+
+    EGLConfig config = q_configFromGLFormat(m_display, m_format, false, EGL_PBUFFER_BIT);
+
+    if (config) {
+        const EGLint attributes[] = {
+            EGL_WIDTH, offscreenSurface->size().width(),
+            EGL_HEIGHT, offscreenSurface->size().height(),
+            EGL_LARGEST_PBUFFER, EGL_FALSE,
+            EGL_NONE
+        };
+
+        m_pbuffer = eglCreatePbufferSurface(m_display, config, attributes);
+
+        if (m_pbuffer != EGL_NO_SURFACE)
+            m_format = q_glFormatFromConfig(m_display, config);
+    }
+}
+
+QEGLPbuffer::~QEGLPbuffer()
+{
+    if (m_pbuffer != EGL_NO_SURFACE)
+        eglDestroySurface(m_display, m_pbuffer);
+}
+
+bool QEGLPbuffer::isValid() const
+{
+    return m_pbuffer != EGL_NO_SURFACE || m_hasSurfaceless;
+}
+
+QT_END_NAMESPACE