Split QQnxWindow into QQnxEglWindow and QQnxRasterWindow

Change-Id: I2fb4096ccca54fa6631aa16c9b8d1308b0a6b918
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Reviewed-by: Thomas McGuire <thomas.mcguire@kdab.com>
Reviewed-by: Kevin Krammer <kevin.krammer@kdab.com>

1 files changed, 234 insertions, 0 deletions

diff --git a/src/plugins/platforms/qnx/qqnxrasterwindow.cpp b/src/plugins/platforms/qnx/qqnxrasterwindow.cpp
new file mode 100644
index 0000000000..fa54b341a5
--- /dev/null
+++ b/src/plugins/platforms/qnx/qqnxrasterwindow.cpp
@@ -0,0 +1,234 @@
+/***************************************************************************
+**
+** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
+** 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 "qqnxrasterwindow.h"
+#include "qqnxscreen.h"
+
+#include <QDebug>
+
+#include <errno.h>
+
+#if defined(QQNXRASTERWINDOW_DEBUG)
+#define qRasterWindowDebug qDebug
+#else
+#define qRasterWindowDebug QT_NO_QDEBUG_MACRO
+#endif
+
+QT_BEGIN_NAMESPACE
+
+QQnxRasterWindow::QQnxRasterWindow(QWindow *window, screen_context_t context) :
+    QQnxWindow(window, context),
+    m_currentBufferIndex(-1),
+    m_previousBufferIndex(-1)
+{
+    initWindow();
+}
+
+void QQnxRasterWindow::post(const QRegion &dirty)
+{
+    // How double-buffering works
+    // --------------------------
+    //
+    // The are two buffers, the previous one and the current one.
+    // The previous buffer always contains the complete, full image of the whole window when it
+    // was last posted.
+    // The current buffer starts with the complete, full image of the second to last posting
+    // of the window.
+    //
+    // During painting, Qt paints on the current buffer. Thus, when Qt has finished painting, the
+    // current buffer contains the second to last image plus the newly painted regions.
+    // Since the second to last image is too old, we copy over the image from the previous buffer, but
+    // only for those regions that Qt didn't paint (because that would overwrite what Qt has just
+    // painted). This is the copyPreviousToCurrent() call below.
+    //
+    // After the call to copyPreviousToCurrent(), the current buffer contains the complete, full image of the
+    // whole window in its current state, and we call screen_post_window() to make the new buffer
+    // available to libscreen (called "posting"). There, only the regions that Qt painted on are
+    // posted, as nothing else has changed.
+    //
+    // After that, the previous and the current buffers are swapped, and the whole cycle starts anew.
+
+    // Check if render buffer exists and something was rendered
+    if (m_currentBufferIndex != -1 && !dirty.isEmpty()) {
+        qRasterWindowDebug() << Q_FUNC_INFO << "window =" << window();
+        QQnxBuffer &currentBuffer = m_buffers[m_currentBufferIndex];
+
+        // Copy unmodified region from old render buffer to new render buffer;
+        // required to allow partial updates
+        QRegion preserve = m_previousDirty - dirty - m_scrolled;
+        blitPreviousToCurrent(preserve, 0, 0);
+
+        // Calculate region that changed
+        QRegion modified = preserve + dirty + m_scrolled;
+        QRect rect = modified.boundingRect();
+        int dirtyRect[4] = { rect.x(), rect.y(), rect.x() + rect.width(), rect.y() + rect.height() };
+
+        // Update the display with contents of render buffer
+        errno = 0;
+        int result = screen_post_window(nativeHandle(), currentBuffer.nativeBuffer(), 1, dirtyRect, 0);
+        if (result != 0)
+            qFatal("QQnxWindow: failed to post window buffer, errno=%d", errno);
+
+        // Advance to next nender buffer
+        m_previousBufferIndex = m_currentBufferIndex++;
+        if (m_currentBufferIndex >= MAX_BUFFER_COUNT)
+            m_currentBufferIndex = 0;
+
+        // Save modified region and clear scrolled region
+        m_previousDirty = dirty;
+        m_scrolled = QRegion();
+        // Notify screen that window posted
+        if (screen() != 0)
+            screen()->onWindowPost(this);
+    }
+}
+
+void QQnxRasterWindow::scroll(const QRegion &region, int dx, int dy, bool flush)
+{
+    qRasterWindowDebug() << Q_FUNC_INFO << "window =" << window();
+    blitPreviousToCurrent(region, dx, dy, flush);
+    m_scrolled += region;
+}
+
+QQnxBuffer &QQnxRasterWindow::renderBuffer()
+{
+    qRasterWindowDebug() << Q_FUNC_INFO << "window =" << window();
+
+    // Check if render buffer is invalid
+    if (m_currentBufferIndex == -1) {
+        // Get all buffers available for rendering
+        errno = 0;
+        screen_buffer_t buffers[MAX_BUFFER_COUNT];
+        int result = screen_get_window_property_pv(nativeHandle(), SCREEN_PROPERTY_RENDER_BUFFERS, (void **)buffers);
+        if (result != 0)
+            qFatal("QQnxRasterWindow: failed to query window buffers, errno=%d", errno);
+
+        // Wrap each buffer and clear
+        for (int i = 0; i < MAX_BUFFER_COUNT; ++i) {
+            m_buffers[i] = QQnxBuffer(buffers[i]);
+
+            // Clear Buffer
+            errno = 0;
+            int bg[] = { SCREEN_BLIT_COLOR, 0x00000000, SCREEN_BLIT_END };
+            result = screen_fill(screen()->nativeContext(), buffers[i], bg);
+            if (result != 0)
+                qFatal("QQnxWindow: failed to clear window buffer, errno=%d", errno);
+        }
+
+        errno = 0;
+        result = screen_flush_blits(screen()->nativeContext(), 0);
+        if (result != 0)
+            qFatal("QQnxWindow: failed to flush blits, errno=%d", errno);
+
+        // Use the first available render buffer
+        m_currentBufferIndex = 0;
+        m_previousBufferIndex = -1;
+    }
+
+    return m_buffers[m_currentBufferIndex];
+}
+
+int QQnxRasterWindow::pixelFormat() const
+{
+    return screen()->nativeFormat();
+}
+
+void QQnxRasterWindow::resetBuffers()
+{
+    // Buffers were destroyed; reacquire them
+    m_currentBufferIndex = -1;
+    m_previousDirty = QRegion();
+    m_scrolled = QRegion();
+}
+
+void QQnxRasterWindow::blitPreviousToCurrent(const QRegion &region, int dx, int dy, bool flush)
+{
+    qRasterWindowDebug() << Q_FUNC_INFO << "window =" << window();
+
+    // Abort if previous buffer is invalid or if nothing to copy
+    if (m_previousBufferIndex == -1 || region.isEmpty())
+        return;
+
+    QQnxBuffer &currentBuffer = m_buffers[m_currentBufferIndex];
+    QQnxBuffer &previousBuffer = m_buffers[m_previousBufferIndex];
+
+    // Break down region into non-overlapping rectangles
+    const QVector<QRect> rects = region.rects();
+    for (int i = rects.size() - 1; i >= 0; i--) {
+        // Clip rectangle to bounds of target
+        const QRect rect = rects[i].intersected(currentBuffer.rect());
+
+        if (rect.isEmpty())
+            continue;
+
+        // Setup blit operation
+        int attribs[] = { SCREEN_BLIT_SOURCE_X, rect.x(),
+                          SCREEN_BLIT_SOURCE_Y, rect.y(),
+                          SCREEN_BLIT_SOURCE_WIDTH, rect.width(),
+                          SCREEN_BLIT_SOURCE_HEIGHT, rect.height(),
+                          SCREEN_BLIT_DESTINATION_X, rect.x() + dx,
+                          SCREEN_BLIT_DESTINATION_Y, rect.y() + dy,
+                          SCREEN_BLIT_DESTINATION_WIDTH, rect.width(),
+                          SCREEN_BLIT_DESTINATION_HEIGHT, rect.height(),
+                          SCREEN_BLIT_END };
+
+        // Queue blit operation
+        errno = 0;
+        const int result = screen_blit(m_screenContext, currentBuffer.nativeBuffer(),
+                                       previousBuffer.nativeBuffer(), attribs);
+        if (result != 0)
+            qFatal("QQnxWindow: failed to blit buffers, errno=%d", errno);
+    }
+
+    // Check if flush requested
+    if (flush) {
+        // Wait for all blits to complete
+        errno = 0;
+        const int result = screen_flush_blits(m_screenContext, SCREEN_WAIT_IDLE);
+        if (result != 0)
+            qFatal("QQnxWindow: failed to flush blits, errno=%d", errno);
+
+        // Buffer was modified outside the CPU
+        currentBuffer.invalidateInCache();
+    }
+}
+
+QT_END_NAMESPACE