Simplify texture pooling logic in GL graphics system.

Remove ugly TemporarilyCachedBindOption and use QGLTexture
objects as texture pool entries instead of QGLPixmapData.
Make texture pooling totally Symbian specific, remove
VG like texture pooling code and use common texture binding
path which is used on other platforms also on Symbian.
QGLPixmapData should be only used to bind SgImage based
textures (will be implemented by another commit).

Task-number: QTBUG-19180
Reviewed-by: Samuel Rødal

1 files changed, 891 insertions, 0 deletions

diff --git a/src/opengl/qpixmapdata_symbiangl.cpp b/src/opengl/qpixmapdata_symbiangl.cpp
new file mode 100644
index 0000000..8c3d61a
--- /dev/null
+++ b/src/opengl/qpixmapdata_symbiangl.cpp
@@ -0,0 +1,891 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtOpenGL module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** 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, Nokia gives you certain additional
+** rights. These rights are described in the Nokia 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.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qpixmap.h"
+#include "qglframebufferobject.h"
+
+#include <private/qpaintengine_raster_p.h>
+
+#include "qpixmapdata_gl_p.h"
+
+#include <private/qgl_p.h>
+#include <private/qdrawhelper_p.h>
+#include <private/qimage_p.h>
+#include <private/qnativeimagehandleprovider_p.h>
+
+#include <private/qpaintengineex_opengl2_p.h>
+
+#include <qdesktopwidget.h>
+#include <qfile.h>
+#include <qimagereader.h>
+#include <qbuffer.h>
+
+#include "qgltexturepool_p.h"
+
+QT_BEGIN_NAMESPACE
+
+Q_OPENGL_EXPORT extern QGLWidget* qt_gl_share_widget();
+
+static inline int areaDiff(const QSize &size, const QGLFramebufferObject *fbo)
+{
+    return qAbs(size.width() * size.height() - fbo->width() * fbo->height());
+}
+
+extern int qt_next_power_of_two(int v);
+
+static inline QSize maybeRoundToNextPowerOfTwo(const QSize &sz)
+{
+#ifdef QT_OPENGL_ES_2
+    QSize rounded(qt_next_power_of_two(sz.width()), qt_next_power_of_two(sz.height()));
+    if (rounded.width() * rounded.height() < 1.20 * sz.width() * sz.height())
+        return rounded;
+#endif
+    return sz;
+}
+
+
+QGLFramebufferObject *QGLFramebufferObjectPool::acquire(const QSize &requestSize, const QGLFramebufferObjectFormat &requestFormat, bool strictSize)
+{
+    QGLFramebufferObject *chosen = 0;
+    QGLFramebufferObject *candidate = 0;
+    for (int i = 0; !chosen && i < m_fbos.size(); ++i) {
+        QGLFramebufferObject *fbo = m_fbos.at(i);
+
+        if (strictSize) {
+            if (fbo->size() == requestSize && fbo->format() == requestFormat) {
+                chosen = fbo;
+                break;
+            } else {
+                continue;
+            }
+        }
+
+        if (fbo->format() == requestFormat) {
+            // choose the fbo with a matching format and the closest size
+            if (!candidate || areaDiff(requestSize, candidate) > areaDiff(requestSize, fbo))
+                candidate = fbo;
+        }
+
+        if (candidate) {
+            m_fbos.removeOne(candidate);
+
+            const QSize fboSize = candidate->size();
+            QSize sz = fboSize;
+
+            if (sz.width() < requestSize.width())
+                sz.setWidth(qMax(requestSize.width(), qRound(sz.width() * 1.5)));
+            if (sz.height() < requestSize.height())
+                sz.setHeight(qMax(requestSize.height(), qRound(sz.height() * 1.5)));
+
+            // wasting too much space?
+            if (sz.width() * sz.height() > requestSize.width() * requestSize.height() * 4)
+                sz = requestSize;
+
+            if (sz != fboSize) {
+                delete candidate;
+                candidate = new QGLFramebufferObject(maybeRoundToNextPowerOfTwo(sz), requestFormat);
+            }
+
+            chosen = candidate;
+        }
+    }
+
+    if (!chosen) {
+        if (strictSize)
+            chosen = new QGLFramebufferObject(requestSize, requestFormat);
+        else
+            chosen = new QGLFramebufferObject(maybeRoundToNextPowerOfTwo(requestSize), requestFormat);
+    }
+
+    if (!chosen->isValid()) {
+        delete chosen;
+        chosen = 0;
+    }
+
+    return chosen;
+}
+
+void QGLFramebufferObjectPool::release(QGLFramebufferObject *fbo)
+{
+    if (fbo)
+        m_fbos << fbo;
+}
+
+
+QPaintEngine* QGLPixmapGLPaintDevice::paintEngine() const
+{
+    return data->paintEngine();
+}
+
+void QGLPixmapGLPaintDevice::beginPaint()
+{
+    if (!data->isValid())
+        return;
+
+    // QGLPaintDevice::beginPaint will store the current binding and replace
+    // it with m_thisFBO:
+    m_thisFBO = data->m_renderFbo->handle();
+    QGLPaintDevice::beginPaint();
+
+    Q_ASSERT(data->paintEngine()->type() == QPaintEngine::OpenGL2);
+
+    // QPixmap::fill() is deferred until now, where we actually need to do the fill:
+    if (data->needsFill()) {
+        const QColor &c = data->fillColor();
+        float alpha = c.alphaF();
+        glDisable(GL_SCISSOR_TEST);
+        glClearColor(c.redF() * alpha, c.greenF() * alpha, c.blueF() * alpha, alpha);
+        glClear(GL_COLOR_BUFFER_BIT);
+    }
+    else if (!data->isUninitialized()) {
+        // If the pixmap (GL Texture) has valid content (it has been
+        // uploaded from an image or rendered into before), we need to
+        // copy it from the texture to the render FBO.
+
+        glDisable(GL_DEPTH_TEST);
+        glDisable(GL_SCISSOR_TEST);
+        glDisable(GL_BLEND);
+
+#if !defined(QT_OPENGL_ES_2)
+        glMatrixMode(GL_MODELVIEW);
+        glLoadIdentity();
+
+        glMatrixMode(GL_PROJECTION);
+        glLoadIdentity();
+        glOrtho(0, data->width(), data->height(), 0, -999999, 999999);
+#endif
+
+        glViewport(0, 0, data->width(), data->height());
+
+        // Pass false to bind so it doesn't copy the FBO into the texture!
+        context()->drawTexture(QRect(0, 0, data->width(), data->height()), data->bind(false));
+    }
+}
+
+void QGLPixmapGLPaintDevice::endPaint()
+{
+    if (!data->isValid())
+        return;
+
+    data->copyBackFromRenderFbo(false);
+
+    // Base's endPaint will restore the previous FBO binding
+    QGLPaintDevice::endPaint();
+
+    qgl_fbo_pool()->release(data->m_renderFbo);
+    data->m_renderFbo = 0;
+}
+
+QGLContext* QGLPixmapGLPaintDevice::context() const
+{
+    data->ensureCreated();
+    return data->m_ctx;
+}
+
+QSize QGLPixmapGLPaintDevice::size() const
+{
+    return data->size();
+}
+
+bool QGLPixmapGLPaintDevice::alphaRequested() const
+{
+    return data->m_hasAlpha;
+}
+
+void QGLPixmapGLPaintDevice::setPixmapData(QGLPixmapData* d)
+{
+    data = d;
+}
+
+int qt_gl_pixmap_serial = 0;
+
+QGLPixmapData::QGLPixmapData(PixelType type)
+    : QPixmapData(type, OpenGLClass)
+    , m_renderFbo(0)
+    , m_engine(0)
+    , m_ctx(0)
+    , nativeImageHandleProvider(0)
+    , nativeImageHandle(0)
+    , m_dirty(false)
+    , m_hasFillColor(false)
+    , m_hasAlpha(false)
+{
+    setSerialNumber(++qt_gl_pixmap_serial);
+    m_glDevice.setPixmapData(this);
+}
+
+QGLPixmapData::~QGLPixmapData()
+{
+    delete m_engine;
+}
+
+QPixmapData *QGLPixmapData::createCompatiblePixmapData() const
+{
+    return new QGLPixmapData(pixelType());
+}
+
+bool QGLPixmapData::isValid() const
+{
+    return w > 0 && h > 0;
+}
+
+bool QGLPixmapData::isValidContext(const QGLContext *ctx) const
+{
+    // On Symbian, we usually want to treat QGLPixmapData as
+    // raster pixmap data because that's well known and tested
+    // execution path which is used on other platforms as well.
+    // That's why if source pixels are valid we return false
+    // to simulate raster pixmaps. Only QPixmaps created from
+    // SgImage will enable usage of QGLPixmapData.
+    return false;
+}
+
+void QGLPixmapData::resize(int width, int height)
+{
+    if (width == w && height == h)
+        return;
+
+    if (width <= 0 || height <= 0) {
+        width = 0;
+        height = 0;
+    }
+
+    w = width;
+    h = height;
+    is_null = (w <= 0 || h <= 0);
+    d = pixelType() == QPixmapData::PixmapType ? 32 : 1;
+
+    destroyTexture();
+
+    m_source = QVolatileImage();
+    m_dirty = isValid();
+    setSerialNumber(++qt_gl_pixmap_serial);
+}
+
+void QGLPixmapData::ensureCreated() const
+{
+    if (!m_dirty)
+        return;
+
+    m_dirty = false;
+
+    if (nativeImageHandleProvider && !nativeImageHandle)
+        const_cast<QGLPixmapData *>(this)->createFromNativeImageHandleProvider();
+
+    QGLShareContextScope ctx(qt_gl_share_widget()->context());
+    m_ctx = ctx;
+
+    const GLenum internal_format = m_hasAlpha ? GL_RGBA : GL_RGB;
+#ifdef QT_OPENGL_ES_2
+    const GLenum external_format = internal_format;
+#else
+    const GLenum external_format = qt_gl_preferredTextureFormat();
+#endif
+    const GLenum target = GL_TEXTURE_2D;
+
+    GLenum type = GL_UNSIGNED_BYTE;
+    // Avoid conversion when pixmap is created from CFbsBitmap of EColor64K.
+    if (!m_source.isNull() && m_source.format() == QImage::Format_RGB16)
+        type = GL_UNSIGNED_SHORT_5_6_5;
+
+    if (!m_texture.id) {
+        m_texture.id = QGLTexturePool::instance()->createTexture(
+                                                                target,
+                                                                0, internal_format,
+                                                                w, h,
+                                                                external_format,
+                                                                type,
+                                                                &m_texture);
+        if (!m_texture.id) {
+            m_texture.failedToAlloc = true;
+            return;
+        }
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+        m_texture.inTexturePool = true;
+    } else if (m_texture.inTexturePool) {
+        glBindTexture(target, m_texture.id);
+        QGLTexturePool::instance()->useTexture(&m_texture);
+    }
+
+    if (!m_source.isNull() && m_texture.id) {
+        if (external_format == GL_RGB) {
+            m_source.beginDataAccess();
+            QImage tx;
+            if (type == GL_UNSIGNED_BYTE)
+                tx = m_source.imageRef().convertToFormat(QImage::Format_RGB888).mirrored(false, true);
+            else if (type == GL_UNSIGNED_SHORT_5_6_5)
+                tx = m_source.imageRef().mirrored(false, true);
+            m_source.endDataAccess(true);
+
+            glBindTexture(target, m_texture.id);
+            if (!tx.isNull())
+                glTexSubImage2D(target, 0, 0, 0, w, h, external_format,
+                                type, tx.constBits());
+            else
+                qWarning("QGLPixmapData: Failed to create GL_RGB image of size %dx%d", w, h);
+        } else {
+            // do byte swizzling ARGB -> RGBA
+            m_source.beginDataAccess();
+            const QImage tx = ctx->d_func()->convertToGLFormat(m_source.imageRef(), true, external_format);
+            m_source.endDataAccess(true);
+            glBindTexture(target, m_texture.id);
+            if (!tx.isNull())
+                glTexSubImage2D(target, 0, 0, 0, w, h, external_format,
+                                type, tx.constBits());
+            else
+                qWarning("QGLPixmapData: Failed to create GL_RGBA image of size %dx%d", w, h);
+        }
+
+        if (useFramebufferObjects())
+            m_source = QVolatileImage();
+    }
+}
+
+
+void QGLPixmapData::fromImage(const QImage &image,
+                              Qt::ImageConversionFlags flags)
+{
+    QImage img = image;
+    createPixmapForImage(img, flags, false);
+}
+
+void QGLPixmapData::fromImageReader(QImageReader *imageReader,
+                                 Qt::ImageConversionFlags flags)
+{
+    QImage image = imageReader->read();
+    if (image.isNull())
+        return;
+
+    createPixmapForImage(image, flags, true);
+}
+
+bool QGLPixmapData::fromFile(const QString &filename, const char *format,
+                             Qt::ImageConversionFlags flags)
+{
+    if (pixelType() == QPixmapData::BitmapType)
+        return QPixmapData::fromFile(filename, format, flags);
+    QFile file(filename);
+    if (file.open(QIODevice::ReadOnly)) {
+        QByteArray data = file.peek(64);
+        bool alpha;
+        if (m_texture.canBindCompressedTexture
+                (data.constData(), data.size(), format, &alpha)) {
+            resize(0, 0);
+            data = file.readAll();
+            file.close();
+            QGLShareContextScope ctx(qt_gl_share_widget()->context());
+            QSize size = m_texture.bindCompressedTexture
+                (data.constData(), data.size(), format);
+            if (!size.isEmpty()) {
+                w = size.width();
+                h = size.height();
+                is_null = false;
+                d = 32;
+                m_hasAlpha = alpha;
+                m_source = QVolatileImage();
+                m_dirty = isValid();
+                return true;
+            }
+            return false;
+        }
+    }
+
+    QImage image = QImageReader(filename, format).read();
+    if (image.isNull())
+        return false;
+
+    createPixmapForImage(image, flags, true);
+
+    return !isNull();
+}
+
+bool QGLPixmapData::fromData(const uchar *buffer, uint len, const char *format,
+                             Qt::ImageConversionFlags flags)
+{
+    bool alpha;
+    const char *buf = reinterpret_cast<const char *>(buffer);
+    if (m_texture.canBindCompressedTexture(buf, int(len), format, &alpha)) {
+        resize(0, 0);
+        QGLShareContextScope ctx(qt_gl_share_widget()->context());
+        QSize size = m_texture.bindCompressedTexture(buf, int(len), format);
+        if (!size.isEmpty()) {
+            w = size.width();
+            h = size.height();
+            is_null = false;
+            d = 32;
+            m_hasAlpha = alpha;
+            m_source = QVolatileImage();
+            m_dirty = isValid();
+            return true;
+        }
+    }
+
+    QByteArray a = QByteArray::fromRawData(reinterpret_cast<const char *>(buffer), len);
+    QBuffer b(&a);
+    b.open(QIODevice::ReadOnly);
+    QImage image = QImageReader(&b, format).read();
+    if (image.isNull())
+        return false;
+
+    createPixmapForImage(image, flags, true);
+
+    return !isNull();
+}
+
+QImage::Format QGLPixmapData::idealFormat(QImage &image, Qt::ImageConversionFlags flags)
+{
+    QImage::Format format = QImage::Format_RGB32;
+    if (qApp->desktop()->depth() == 16)
+        format = QImage::Format_RGB16;
+
+    if (image.hasAlphaChannel()
+        && ((flags & Qt::NoOpaqueDetection)
+            || const_cast<QImage &>(image).data_ptr()->checkForAlphaPixels()))
+        format = QImage::Format_ARGB32_Premultiplied;
+
+    return format;
+}
+
+void QGLPixmapData::createPixmapForImage(QImage &image, Qt::ImageConversionFlags flags, bool inPlace)
+{
+    if (image.size() == QSize(w, h))
+        setSerialNumber(++qt_gl_pixmap_serial);
+
+    resize(image.width(), image.height());
+
+    if (pixelType() == BitmapType) {
+        QImage convertedImage = image.convertToFormat(QImage::Format_MonoLSB);
+        if (image.format() == QImage::Format_MonoLSB)
+            convertedImage.detach();
+
+        m_source = QVolatileImage(convertedImage);
+
+    } else {
+        QImage::Format format = idealFormat(image, flags);
+
+        if (inPlace && image.data_ptr()->convertInPlace(format, flags)) {
+            m_source = QVolatileImage(image);
+        } else {
+            QImage convertedImage = image.convertToFormat(format);
+
+            // convertToFormat won't detach the image if format stays the same.
+            if (image.format() == format)
+                convertedImage.detach();
+
+            m_source = QVolatileImage(convertedImage);
+        }
+    }
+
+    m_dirty = true;
+    m_hasFillColor = false;
+
+    m_hasAlpha = m_source.hasAlphaChannel();
+    w = image.width();
+    h = image.height();
+    is_null = (w <= 0 || h <= 0);
+    d = m_source.depth();
+
+    destroyTexture();
+}
+
+bool QGLPixmapData::scroll(int dx, int dy, const QRect &rect)
+{
+    Q_UNUSED(dx);
+    Q_UNUSED(dy);
+    Q_UNUSED(rect);
+    return false;
+}
+
+void QGLPixmapData::copy(const QPixmapData *data, const QRect &rect)
+{
+    if (data->classId() != QPixmapData::OpenGLClass || !static_cast<const QGLPixmapData *>(data)->useFramebufferObjects()) {
+        QPixmapData::copy(data, rect);
+        return;
+    }
+
+    const QGLPixmapData *other = static_cast<const QGLPixmapData *>(data);
+    if (other->m_renderFbo) {
+        QGLShareContextScope ctx(qt_gl_share_widget()->context());
+
+        resize(rect.width(), rect.height());
+        m_hasAlpha = other->m_hasAlpha;
+        ensureCreated();
+
+        if (!ctx->d_ptr->fbo)
+            glGenFramebuffers(1, &ctx->d_ptr->fbo);
+
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, ctx->d_ptr->fbo);
+        glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                GL_TEXTURE_2D, m_texture.id, 0);
+
+        if (!other->m_renderFbo->isBound())
+            glBindFramebuffer(GL_READ_FRAMEBUFFER_EXT, other->m_renderFbo->handle());
+
+        glDisable(GL_SCISSOR_TEST);
+        if (ctx->d_ptr->active_engine && ctx->d_ptr->active_engine->type() == QPaintEngine::OpenGL2)
+            static_cast<QGL2PaintEngineEx *>(ctx->d_ptr->active_engine)->invalidateState();
+
+        glBlitFramebufferEXT(rect.x(), rect.y(), rect.x() + rect.width(), rect.y() + rect.height(),
+                0, 0, w, h,
+                GL_COLOR_BUFFER_BIT,
+                GL_NEAREST);
+
+        glBindFramebuffer(GL_FRAMEBUFFER_EXT, ctx->d_ptr->current_fbo);
+    } else {
+        QPixmapData::copy(data, rect);
+    }
+}
+
+void QGLPixmapData::fill(const QColor &color)
+{
+    if (!isValid())
+        return;
+
+    bool hasAlpha = color.alpha() != 255;
+    if (hasAlpha && !m_hasAlpha) {
+        if (m_texture.id) {
+            destroyTexture();
+            m_dirty = true;
+        }
+        m_hasAlpha = color.alpha() != 255;
+    }
+
+    if (useFramebufferObjects()) {
+        m_source = QVolatileImage();
+        m_hasFillColor = true;
+        m_fillColor = color;
+    } else {
+        forceToImage();
+
+        if (m_source.depth() == 32) {
+            m_source.fill(PREMUL(color.rgba()));
+
+        } else if (m_source.depth() == 1) {
+            if (color == Qt::color1)
+                m_source.fill(1);
+            else
+                m_source.fill(0);
+        }
+    }
+}
+
+bool QGLPixmapData::hasAlphaChannel() const
+{
+    return m_hasAlpha;
+}
+
+QImage QGLPixmapData::fillImage(const QColor &color) const
+{
+    QImage img;
+    if (pixelType() == BitmapType) {
+        img = QImage(w, h, QImage::Format_MonoLSB);
+
+        img.setColorCount(2);
+        img.setColor(0, QColor(Qt::color0).rgba());
+        img.setColor(1, QColor(Qt::color1).rgba());
+
+        if (color == Qt::color1)
+            img.fill(1);
+        else
+            img.fill(0);
+    } else {
+        img = QImage(w, h,
+                m_hasAlpha
+                ? QImage::Format_ARGB32_Premultiplied
+                : QImage::Format_RGB32);
+        img.fill(PREMUL(color.rgba()));
+    }
+    return img;
+}
+
+extern QImage qt_gl_read_texture(const QSize &size, bool alpha_format, bool include_alpha);
+
+QImage QGLPixmapData::toImage() const
+{
+    if (!isValid())
+        return QImage();
+
+    if (m_renderFbo) {
+        copyBackFromRenderFbo(true);
+    } else if (!m_source.isNull()) {
+        // QVolatileImage::toImage() will make a copy always so no check
+        // for active painting is needed.
+        QImage img = m_source.toImage();
+        if (img.format() == QImage::Format_MonoLSB) {
+            img.setColorCount(2);
+            img.setColor(0, QColor(Qt::color0).rgba());
+            img.setColor(1, QColor(Qt::color1).rgba());
+        }
+        return img;
+    } else if (m_dirty || m_hasFillColor) {
+        return fillImage(m_fillColor);
+    } else {
+        ensureCreated();
+    }
+
+    QGLShareContextScope ctx(qt_gl_share_widget()->context());
+    glBindTexture(GL_TEXTURE_2D, m_texture.id);
+    return qt_gl_read_texture(QSize(w, h), true, true);
+}
+
+struct TextureBuffer
+{
+    QGLFramebufferObject *fbo;
+    QGL2PaintEngineEx *engine;
+};
+
+Q_GLOBAL_STATIC(QGLFramebufferObjectPool, _qgl_fbo_pool)
+QGLFramebufferObjectPool* qgl_fbo_pool()
+{
+    return _qgl_fbo_pool();
+}
+
+void QGLPixmapData::copyBackFromRenderFbo(bool keepCurrentFboBound) const
+{
+    if (!isValid())
+        return;
+
+    m_hasFillColor = false;
+
+    const QGLContext *share_ctx = qt_gl_share_widget()->context();
+    QGLShareContextScope ctx(share_ctx);
+
+    ensureCreated();
+
+    if (!ctx->d_ptr->fbo)
+        glGenFramebuffers(1, &ctx->d_ptr->fbo);
+
+    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, ctx->d_ptr->fbo);
+    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+        GL_TEXTURE_2D, m_texture.id, 0);
+
+    const int x0 = 0;
+    const int x1 = w;
+    const int y0 = 0;
+    const int y1 = h;
+
+    if (!m_renderFbo->isBound())
+        glBindFramebuffer(GL_READ_FRAMEBUFFER_EXT, m_renderFbo->handle());
+
+    glDisable(GL_SCISSOR_TEST);
+
+    glBlitFramebufferEXT(x0, y0, x1, y1,
+            x0, y0, x1, y1,
+            GL_COLOR_BUFFER_BIT,
+            GL_NEAREST);
+
+    if (keepCurrentFboBound) {
+        glBindFramebuffer(GL_FRAMEBUFFER_EXT, ctx->d_ptr->current_fbo);
+    } else {
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, m_renderFbo->handle());
+        ctx->d_ptr->current_fbo = m_renderFbo->handle();
+    }
+}
+
+bool QGLPixmapData::useFramebufferObjects() const
+{
+    // We don't use FBOs on Symbian for now
+    return false;
+}
+
+QPaintEngine* QGLPixmapData::paintEngine() const
+{
+    if (!isValid())
+        return 0;
+
+    if (m_renderFbo)
+        return m_engine;
+
+    if (useFramebufferObjects()) {
+        extern QGLWidget* qt_gl_share_widget();
+
+        if (!QGLContext::currentContext())
+            qt_gl_share_widget()->makeCurrent();
+        QGLShareContextScope ctx(qt_gl_share_widget()->context());
+
+        QGLFramebufferObjectFormat format;
+        format.setAttachment(QGLFramebufferObject::CombinedDepthStencil);
+        format.setSamples(4);
+        format.setInternalTextureFormat(GLenum(m_hasAlpha ? GL_RGBA : GL_RGB));
+
+        m_renderFbo = qgl_fbo_pool()->acquire(size(), format);
+
+        if (m_renderFbo) {
+            if (!m_engine)
+                m_engine = new QGL2PaintEngineEx;
+            return m_engine;
+        }
+
+        qWarning() << "Failed to create pixmap texture buffer of size " << size() << ", falling back to raster paint engine";
+    }
+
+    // If the application wants to paint into the QPixmap, we first
+    // force it to QImage format and then paint into that.
+    // This is simpler than juggling multiple GL contexts.
+    const_cast<QGLPixmapData *>(this)->forceToImage();
+
+    if (m_hasFillColor) {
+        m_source.fill(PREMUL(m_fillColor.rgba()));
+        m_hasFillColor = false;
+    }
+    return m_source.paintEngine();
+}
+
+extern QRgb qt_gl_convertToGLFormat(QRgb src_pixel, GLenum texture_format);
+
+// If copyBack is true, bind will copy the contents of the render
+// FBO to the texture (which is not bound to the texture, as it's
+// a multisample FBO).
+GLuint QGLPixmapData::bind(bool copyBack) const
+{
+    if (m_renderFbo && copyBack) {
+        copyBackFromRenderFbo(true);
+    } else {
+        ensureCreated();
+    }
+
+    GLuint id = m_texture.id;
+    glBindTexture(GL_TEXTURE_2D, id);
+
+    if (m_hasFillColor) {
+        if (!useFramebufferObjects()) {
+            m_source = QVolatileImage(w, h, QImage::Format_ARGB32_Premultiplied);
+            m_source.fill(PREMUL(m_fillColor.rgba()));
+        }
+
+        m_hasFillColor = false;
+
+        GLenum format = qt_gl_preferredTextureFormat();
+        QImage tx(w, h, QImage::Format_ARGB32_Premultiplied);
+        tx.fill(qt_gl_convertToGLFormat(m_fillColor.rgba(), format));
+        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, w, h, format, GL_UNSIGNED_BYTE, tx.constBits());
+    }
+
+    return id;
+}
+
+QGLTexture* QGLPixmapData::texture() const
+{
+    return &m_texture;
+}
+
+Q_GUI_EXPORT int qt_defaultDpiX();
+Q_GUI_EXPORT int qt_defaultDpiY();
+
+int QGLPixmapData::metric(QPaintDevice::PaintDeviceMetric metric) const
+{
+    if (w == 0)
+        return 0;
+
+    switch (metric) {
+    case QPaintDevice::PdmWidth:
+        return w;
+    case QPaintDevice::PdmHeight:
+        return h;
+    case QPaintDevice::PdmNumColors:
+        return 0;
+    case QPaintDevice::PdmDepth:
+        return d;
+    case QPaintDevice::PdmWidthMM:
+        return qRound(w * 25.4 / qt_defaultDpiX());
+    case QPaintDevice::PdmHeightMM:
+        return qRound(h * 25.4 / qt_defaultDpiY());
+    case QPaintDevice::PdmDpiX:
+    case QPaintDevice::PdmPhysicalDpiX:
+        return qt_defaultDpiX();
+    case QPaintDevice::PdmDpiY:
+    case QPaintDevice::PdmPhysicalDpiY:
+        return qt_defaultDpiY();
+    default:
+        qWarning("QGLPixmapData::metric(): Invalid metric");
+        return 0;
+    }
+}
+
+// Force the pixmap data to be backed by some valid data.
+void QGLPixmapData::forceToImage()
+{
+    if (!isValid())
+        return;
+
+    if (m_source.isNull()) {
+        QImage::Format format = QImage::Format_ARGB32_Premultiplied;
+        if (pixelType() == BitmapType)
+            format = QImage::Format_MonoLSB;
+        m_source = QVolatileImage(w, h, format);
+    }
+
+    m_dirty = true;
+}
+
+void QGLPixmapData::destroyTexture()
+{
+    // Destroy SgImage texture
+}
+
+void QGLPixmapData::detachTextureFromPool()
+{
+    QGLTexturePool::instance()->detachTexture(&m_texture);
+}
+
+void QGLPixmapData::hibernate()
+{
+    destroyTexture();
+}
+
+void QGLPixmapData::reclaimTexture()
+{
+    if (!m_texture.inTexturePool)
+        return;
+
+    forceToImage();
+
+    destroyTexture();
+}
+
+QGLPaintDevice *QGLPixmapData::glDevice() const
+{
+    return &m_glDevice;
+}
+
+QT_END_NAMESPACE