qpicture.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qpicture.h"
#include <private/qpicture_p.h>
 
#ifndef QT_NO_PICTURE
 
#include <private/qfactoryloader_p.h>
#include <private/qpaintengine_pic_p.h>
#include <private/qfont_p.h>
#include <qguiapplication.h>
 
#include "qdatastream.h"
#include "qfile.h"
#include "qimage.h"
#include "qmutex.h"
#include "qpainter.h"
#include "qpainterpath.h"
#include "qpixmap.h"
#include "qregion.h"
#include "qdebug.h"
#include <QtCore/private/qlocking_p.h>
 
#include <algorithm>
 
QT_BEGIN_NAMESPACE
 
void qt_format_text(const QFont &fnt, const QRectF &_r,
                    int tf, const QTextOption *opt, const QString& str, QRectF *brect,
                    int tabstops, int *, int tabarraylen,
                    QPainter *painter);
 
const char  *qt_mfhdr_tag = "QPIC"; // header tag
static const quint16 mfhdr_maj = QDataStream::Qt_DefaultCompiledVersion; // major version #
static const quint16 mfhdr_min = 0; // minor version #
 
QPicture::QPicture(int formatVersion)
    : QPaintDevice(),
      d_ptr(new QPicturePrivate)
{
    Q_D(QPicture);
 
    if (formatVersion == 0)
        qWarning("QPicture: invalid format version 0");
 
    // still accept the 0 default from before Qt 3.0.
    if (formatVersion > 0 && formatVersion != (int)mfhdr_maj) {
        d->formatMajor = formatVersion;
        d->formatMinor = 0;
        d->formatOk = false;
    } else {
        d->resetFormat();
    }
}
 
QPicture::QPicture(const QPicture &pic)
    : QPaintDevice(), d_ptr(pic.d_ptr)
{
}
 
QPicture::QPicture(QPicturePrivate &dptr)
    : QPaintDevice(),
      d_ptr(&dptr)
{
}
 
QPicture::~QPicture()
{
}
 
int QPicture::devType() const
{
    return QInternal::Picture;
}
 
bool QPicture::isNull() const
{
    return d_func()->pictb.buffer().isNull();
}
 
uint QPicture::size() const
{
    return d_func()->pictb.buffer().size();
}
 
const char* QPicture::data() const
{
    return d_func()->pictb.buffer();
}
 
void QPicture::detach()
{
    d_ptr.detach();
}
 
bool QPicture::isDetached() const
{
    return d_func()->ref.loadRelaxed() == 1;
}
 
void QPicture::setData(const char* data, uint size)
{
    detach();
    d_func()->pictb.setData(data, size);
    d_func()->resetFormat();                                // we'll have to check
}
 
 
bool QPicture::load(const QString &fileName)
{
    QFile f(fileName);
    if (!f.open(QIODevice::ReadOnly)) {
        operator=(QPicture());
        return false;
    }
    return load(&f);
}
 
bool QPicture::load(QIODevice *dev)
{
    detach();
    QByteArray a = dev->readAll();
 
    d_func()->pictb.setData(a);                        // set byte array in buffer
    return d_func()->checkFormat();
}
 
bool QPicture::save(const QString &fileName)
{
    if (paintingActive()) {
        qWarning("QPicture::save: still being painted on. "
                  "Call QPainter::end() first");
        return false;
    }
 
    QFile f(fileName);
    if (!f.open(QIODevice::WriteOnly))
        return false;
    return save(&f);
}
 
bool QPicture::save(QIODevice *dev)
{
    if (paintingActive()) {
        qWarning("QPicture::save: still being painted on. "
                  "Call QPainter::end() first");
        return false;
    }
 
    dev->write(d_func()->pictb.buffer(), d_func()->pictb.buffer().size());
    return true;
}
 
QRect QPicture::boundingRect() const
{
    Q_D(const QPicture);
    // Use override rect where possible.
    if (!d->override_rect.isEmpty())
        return d->override_rect;
 
    if (!d->formatOk)
        d_ptr->checkFormat();
 
    return d->brect;
}
 
void QPicture::setBoundingRect(const QRect &r)
{
    d_func()->override_rect = r;
}
 
bool QPicture::play(QPainter *painter)
{
    Q_D(QPicture);
 
    if (d->pictb.size() == 0)                        // nothing recorded
        return true;
 
    if (!d->formatOk && !d->checkFormat())
        return false;
 
    d->pictb.open(QIODevice::ReadOnly);                // open buffer device
    QDataStream s;
    s.setDevice(&d->pictb);                        // attach data stream to buffer
    s.device()->seek(10);                        // go directly to the data
    s.setVersion(d->formatMajor == 4 ? 3 : d->formatMajor);
 
    quint8  c, clen;
    quint32 nrecords;
    s >> c >> clen;
    Q_ASSERT(c == QPicturePrivate::PdcBegin);
    // bounding rect was introduced in ver 4. Read in checkFormat().
    if (d->formatMajor >= 4) {
        qint32 dummy;
        s >> dummy >> dummy >> dummy >> dummy;
    }
    s >> nrecords;
    if (!exec(painter, s, nrecords)) {
        qWarning("QPicture::play: Format error");
        d->pictb.close();
        return false;
    }
    d->pictb.close();
    return true;                                // no end-command
}
 
 
//
// QFakeDevice is used to create fonts with a custom DPI
//
class QFakeDevice : public QPaintDevice
{
public:
    QFakeDevice() { dpi_x = qt_defaultDpiX(); dpi_y = qt_defaultDpiY(); }
    void setDpiX(int dpi) { dpi_x = dpi; }
    void setDpiY(int dpi) { dpi_y = dpi; }
    QPaintEngine *paintEngine() const override { return nullptr; }
    int metric(PaintDeviceMetric m) const override
    {
        switch(m) {
            case PdmPhysicalDpiX:
            case PdmDpiX:
                return dpi_x;
            case PdmPhysicalDpiY:
            case PdmDpiY:
                return dpi_y;
            default:
                return QPaintDevice::metric(m);
        }
    }
 
private:
    int dpi_x;
    int dpi_y;
};
 
bool QPicture::exec(QPainter *painter, QDataStream &s, int nrecords)
{
    Q_D(QPicture);
#if defined(QT_DEBUG)
    int                strm_pos;
#endif
    quint8     c;                      // command id
    quint8     tiny_len;               // 8-bit length descriptor
    qint32     len;                    // 32-bit length descriptor
    qint16     i_16, i1_16, i2_16;     // parameters...
    qint8      i_8;
    quint32    ul;
    double     dbl;
    bool       bl;
    QByteArray  str1;
    QString     str;
    QPointF     p, p1, p2;
    QPoint      ip, ip1, ip2;
    QRect       ir;
    QRectF      r;
    QPolygonF   a;
    QPolygon    ia;
    QColor      color;
    QFont       font;
    QPen        pen;
    QBrush      brush;
    QRegion     rgn;
    qreal       wmatrix[6];
    QTransform  matrix;
 
    QTransform worldMatrix = painter->transform();
    worldMatrix.scale(qreal(painter->device()->logicalDpiX()) / qreal(qt_defaultDpiX()),
                      qreal(painter->device()->logicalDpiY()) / qreal(qt_defaultDpiY()));
    painter->setTransform(worldMatrix);
 
    while (nrecords-- && !s.atEnd()) {
        s >> c;                 // read cmd
        s >> tiny_len;          // read param length
        if (tiny_len == 255)    // longer than 254 bytes
            s >> len;
        else
            len = tiny_len;
#if defined(QT_DEBUG)
        strm_pos = s.device()->pos();
#endif
        switch (c) {            // exec cmd
        case QPicturePrivate::PdcNOP:
            break;
        case QPicturePrivate::PdcDrawPoint:
            if (d->formatMajor <= 5) {
                s >> ip;
                painter->drawPoint(ip);
            } else {
                s >> p;
                painter->drawPoint(p);
            }
            break;
        case QPicturePrivate::PdcDrawPoints:
// ## implement me in the picture paint engine
//                 s >> a >> i1_32 >> i2_32;
//                 painter->drawPoints(a.mid(i1_32, i2_32));
            break;
        case QPicturePrivate::PdcDrawPath: {
            QPainterPath path;
            s >> path;
            painter->drawPath(path);
            break;
        }
        case QPicturePrivate::PdcDrawLine:
            if (d->formatMajor <= 5) {
                s >> ip1 >> ip2;
                painter->drawLine(ip1, ip2);
            } else {
                s >> p1 >> p2;
                painter->drawLine(p1, p2);
            }
            break;
        case QPicturePrivate::PdcDrawRect:
            if (d->formatMajor <= 5) {
                s >> ir;
                painter->drawRect(ir);
            } else {
                s >> r;
                painter->drawRect(r);
            }
            break;
        case QPicturePrivate::PdcDrawRoundRect:
            if (d->formatMajor <= 5) {
                s >> ir >> i1_16 >> i2_16;
                painter->drawRoundedRect(ir, i1_16, i2_16, Qt::RelativeSize);
            } else {
                s >> r >> i1_16 >> i2_16;
                painter->drawRoundedRect(r, i1_16, i2_16, Qt::RelativeSize);
            }
            break;
        case QPicturePrivate::PdcDrawEllipse:
            if (d->formatMajor <= 5) {
                s >> ir;
                painter->drawEllipse(ir);
            } else {
                s >> r;
                painter->drawEllipse(r);
            }
            break;
        case QPicturePrivate::PdcDrawArc:
            if (d->formatMajor <= 5) {
                s >> ir;
                r = ir;
            } else {
                s >> r;
            }
            s >> i1_16 >> i2_16;
            painter->drawArc(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawPie:
            if (d->formatMajor <= 5) {
                s >> ir;
                r = ir;
            } else {
                s >> r;
            }
            s >> i1_16 >> i2_16;
            painter->drawPie(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawChord:
            if (d->formatMajor <= 5) {
                s >> ir;
                r = ir;
            } else {
                s >> r;
            }
            s >> i1_16 >> i2_16;
            painter->drawChord(r, i1_16, i2_16);
            break;
        case QPicturePrivate::PdcDrawLineSegments:
            s >> ia;
            painter->drawLines(ia);
            ia.clear();
            break;
        case QPicturePrivate::PdcDrawPolyline:
            if (d->formatMajor <= 5) {
                s >> ia;
                painter->drawPolyline(ia);
                ia.clear();
            } else {
                s >> a;
                painter->drawPolyline(a);
                a.clear();
            }
            break;
        case QPicturePrivate::PdcDrawPolygon:
            if (d->formatMajor <= 5) {
                s >> ia >> i_8;
                painter->drawPolygon(ia, i_8 ? Qt::WindingFill : Qt::OddEvenFill);
                ia.clear();
            } else {
                s >> a >> i_8;
                painter->drawPolygon(a, i_8 ? Qt::WindingFill : Qt::OddEvenFill);
                a.clear();
            }
            break;
        case QPicturePrivate::PdcDrawCubicBezier: {
            s >> ia;
            QPainterPath path;
            Q_ASSERT(ia.size() == 4);
            path.moveTo(ia.value(0));
            path.cubicTo(ia.value(1), ia.value(2), ia.value(3));
            painter->strokePath(path, painter->pen());
            ia.clear();
        }
            break;
        case QPicturePrivate::PdcDrawText:
            s >> ip >> str1;
            painter->drawText(ip, QString::fromLatin1(str1));
            break;
        case QPicturePrivate::PdcDrawTextFormatted:
            s >> ir >> i_16 >> str1;
            painter->drawText(ir, i_16, QString::fromLatin1(str1));
            break;
        case QPicturePrivate::PdcDrawText2:
            if (d->formatMajor <= 5) {
                s >> ip >> str;
                painter->drawText(ip, str);
            } else {
                s >> p >> str;
                painter->drawText(p, str);
            }
            break;
        case QPicturePrivate::PdcDrawText2Formatted:
            s >> ir;
            s >> i_16;
            s >> str;
            painter->drawText(ir, i_16, str);
            break;
        case QPicturePrivate::PdcDrawTextItem: {
            s >> p >> str >> font >> ul;
 
            // the text layout direction is not used here because it's already
            // aligned when QPicturePaintEngine::drawTextItem() serializes the
            // drawText() call, therefore ul is unsed in this context
 
            if (d->formatMajor >= 9) {
                s >> dbl;
                QFont fnt(font);
                if (dbl != 1.0) {
                    QFakeDevice fake;
                    fake.setDpiX(qRound(dbl*qt_defaultDpiX()));
                    fake.setDpiY(qRound(dbl*qt_defaultDpiY()));
                    fnt = QFont(font, &fake);
                }
 
                qreal justificationWidth;
                s >> justificationWidth;
 
                int flags = Qt::TextSingleLine | Qt::TextDontClip | Qt::TextForceLeftToRight;
 
                QSizeF size(1, 1);
                if (justificationWidth > 0) {
                    size.setWidth(justificationWidth);
                    flags |= Qt::TextJustificationForced;
                    flags |= Qt::AlignJustify;
                }
 
                QFontMetrics fm(fnt);
                QPointF pt(p.x(), p.y() - fm.ascent());
                qt_format_text(fnt, QRectF(pt, size), flags, /*opt*/nullptr,
                               str, /*brect=*/nullptr, /*tabstops=*/0, /*...*/nullptr, /*tabarraylen=*/0, painter);
            } else {
                qt_format_text(font, QRectF(p, QSizeF(1, 1)), Qt::TextSingleLine | Qt::TextDontClip, /*opt*/nullptr,
                               str, /*brect=*/nullptr, /*tabstops=*/0, /*...*/nullptr, /*tabarraylen=*/0, painter);
            }
 
            break;
        }
        case QPicturePrivate::PdcDrawPixmap: {
            QPixmap pixmap;
            if (d->formatMajor < 4) {
                s >> ip >> pixmap;
                painter->drawPixmap(ip, pixmap);
            } else if (d->formatMajor <= 5) {
                s >> ir >> pixmap;
                painter->drawPixmap(ir, pixmap);
            } else {
                QRectF sr;
                if (d->in_memory_only) {
                    int index;
                    s >> r >> index >> sr;
                    Q_ASSERT(index < d->pixmap_list.size());
                    pixmap = d->pixmap_list.value(index);
                } else {
                    s >> r >> pixmap >> sr;
                }
                painter->drawPixmap(r, pixmap, sr);
            }
        }
            break;
        case QPicturePrivate::PdcDrawTiledPixmap: {
            QPixmap pixmap;
            if (d->in_memory_only) {
                int index;
                s >> r >> index >> p;
                Q_ASSERT(index < d->pixmap_list.size());
                pixmap = d->pixmap_list.value(index);
            } else {
                s >> r >> pixmap >> p;
            }
            painter->drawTiledPixmap(r, pixmap, p);
        }
            break;
        case QPicturePrivate::PdcDrawImage: {
            QImage image;
            if (d->formatMajor < 4) {
                s >> p >> image;
                painter->drawImage(p, image);
            } else if (d->formatMajor <= 5){
                s >> ir >> image;
                painter->drawImage(ir, image, QRect(0, 0, ir.width(), ir.height()));
            } else {
                QRectF sr;
                if (d->in_memory_only) {
                    int index;
                    s >> r >> index >> sr >> ul;
                    Q_ASSERT(index < d->image_list.size());
                    image = d->image_list.value(index);
                } else {
                    s >> r >> image >> sr >> ul;
                }
                painter->drawImage(r, image, sr, Qt::ImageConversionFlags(ul));
            }
        }
            break;
        case QPicturePrivate::PdcBegin:
            s >> ul;                        // number of records
            if (!exec(painter, s, ul))
                return false;
            break;
        case QPicturePrivate::PdcEnd:
            if (nrecords == 0)
                return true;
            break;
        case QPicturePrivate::PdcSave:
            painter->save();
            break;
        case QPicturePrivate::PdcRestore:
            painter->restore();
            break;
        case QPicturePrivate::PdcSetBkColor:
            s >> color;
            painter->setBackground(color);
            break;
        case QPicturePrivate::PdcSetBkMode:
            s >> i_8;
            painter->setBackgroundMode((Qt::BGMode)i_8);
            break;
        case QPicturePrivate::PdcSetROP: // NOP
            s >> i_8;
            break;
        case QPicturePrivate::PdcSetBrushOrigin:
            if (d->formatMajor <= 5) {
                s >> ip;
                painter->setBrushOrigin(ip);
            } else {
                s >> p;
                painter->setBrushOrigin(p);
            }
            break;
        case QPicturePrivate::PdcSetFont:
            s >> font;
            painter->setFont(font);
            break;
        case QPicturePrivate::PdcSetPen:
            if (d->in_memory_only) {
                int index;
                s >> index;
                Q_ASSERT(index < d->pen_list.size());
                pen = d->pen_list.value(index);
            } else {
                s >> pen;
            }
            painter->setPen(pen);
            break;
        case QPicturePrivate::PdcSetBrush:
            if (d->in_memory_only) {
                int index;
                s >> index;
                Q_ASSERT(index < d->brush_list.size());
                brush = d->brush_list.value(index);
            } else {
                s >> brush;
            }
            painter->setBrush(brush);
            break;
        case QPicturePrivate::PdcSetVXform:
            s >> i_8;
            painter->setViewTransformEnabled(i_8);
            break;
        case QPicturePrivate::PdcSetWindow:
            if (d->formatMajor <= 5) {
                s >> ir;
                painter->setWindow(ir);
            } else {
                s >> r;
                painter->setWindow(r.toRect());
            }
            break;
        case QPicturePrivate::PdcSetViewport:
            if (d->formatMajor <= 5) {
                s >> ir;
                painter->setViewport(ir);
            } else {
                s >> r;
                painter->setViewport(r.toRect());
            }
            break;
        case QPicturePrivate::PdcSetWXform:
            s >> i_8;
            painter->setWorldMatrixEnabled(i_8);
            break;
        case QPicturePrivate::PdcSetWMatrix:
            if (d->formatMajor >= 8) {
                s >> matrix >> i_8;
            } else {
                s >> wmatrix[0] >> wmatrix[1]
                  >> wmatrix[2] >> wmatrix[3]
                  >> wmatrix[4] >> wmatrix[5] >> i_8;
                matrix = QTransform(wmatrix[0], wmatrix[1],
                                    wmatrix[2], wmatrix[3],
                                    wmatrix[4], wmatrix[5]);
            }
            // i_8 is always false due to updateXForm() in qpaintengine_pic.cpp
            painter->setTransform(matrix * worldMatrix, i_8);
            break;
        case QPicturePrivate::PdcSetClip:
            s >> i_8;
            painter->setClipping(i_8);
            break;
        case QPicturePrivate::PdcSetClipRegion:
            s >> rgn >> i_8;
            if (d->formatMajor >= 9) {
                painter->setClipRegion(rgn, Qt::ClipOperation(i_8));
            } else {
                painter->setClipRegion(rgn);
            }
            break;
        case QPicturePrivate::PdcSetClipPath:
            {
                QPainterPath path;
                s >> path >> i_8;
                painter->setClipPath(path, Qt::ClipOperation(i_8));
                break;
            }
        case QPicturePrivate::PdcSetRenderHint:
            s >> ul;
            painter->setRenderHint(QPainter::Antialiasing,
                                   bool(ul & QPainter::Antialiasing));
            painter->setRenderHint(QPainter::SmoothPixmapTransform,
                                   bool(ul & QPainter::SmoothPixmapTransform));
            painter->setRenderHint(QPainter::NonCosmeticBrushPatterns,
                                   bool(ul & QPainter::NonCosmeticBrushPatterns));
            break;
        case QPicturePrivate::PdcSetCompositionMode:
            s >> ul;
            painter->setCompositionMode((QPainter::CompositionMode)ul);
            break;
        case QPicturePrivate::PdcSetClipEnabled:
            s >> bl;
            painter->setClipping(bl);
            break;
        case QPicturePrivate::PdcSetOpacity:
            s >> dbl;
            painter->setOpacity(qreal(dbl));
            break;
        default:
            qWarning("QPicture::play: Invalid command %d", c);
            if (len > 0)                    // skip unknown command
                s.device()->seek(s.device()->pos()+len);
        }
#if defined(QT_DEBUG)
        //qDebug("device->at(): %i, strm_pos: %i len: %i", (int)s.device()->pos(), strm_pos, len);
        Q_ASSERT(qint32(s.device()->pos() - strm_pos) == len);
#endif
    }
    return false;
}
 
int QPicture::metric(PaintDeviceMetric m) const
{
    int val;
    QRect brect = boundingRect();
    switch (m) {
        case PdmWidth:
            val = brect.width();
            break;
        case PdmHeight:
            val = brect.height();
            break;
        case PdmWidthMM:
            val = int(25.4/qt_defaultDpiX()*brect.width());
            break;
        case PdmHeightMM:
            val = int(25.4/qt_defaultDpiY()*brect.height());
            break;
        case PdmDpiX:
        case PdmPhysicalDpiX:
            val = qt_defaultDpiX();
            break;
        case PdmDpiY:
        case PdmPhysicalDpiY:
            val = qt_defaultDpiY();
            break;
        case PdmNumColors:
            val = 16777216;
            break;
        case PdmDepth:
            val = 24;
            break;
        case PdmDevicePixelRatio:
            val = 1;
            break;
        case PdmDevicePixelRatioScaled:
            val = 1 * QPaintDevice::devicePixelRatioFScale();
            break;
        default:
            val = 0;
            qWarning("QPicture::metric: Invalid metric command");
    }
    return val;
}
 
QPicture& QPicture::operator=(const QPicture &p)
{
    d_ptr = p.d_ptr;
    return *this;
}
 
QPicturePrivate::QPicturePrivate()
    : in_memory_only(false)
{
}
 
QPicturePrivate::QPicturePrivate(const QPicturePrivate &other)
    : trecs(other.trecs),
      formatOk(other.formatOk),
      formatMinor(other.formatMinor),
      brect(other.brect),
      override_rect(other.override_rect),
      in_memory_only(false)
{
    pictb.setData(other.pictb.data(), other.pictb.size());
    if (other.pictb.isOpen()) {
        pictb.open(other.pictb.openMode());
        pictb.seek(other.pictb.pos());
    }
}
 
void QPicturePrivate::resetFormat()
{
    formatOk = false;
    formatMajor = mfhdr_maj;
    formatMinor = mfhdr_min;
}
 
 
bool QPicturePrivate::checkFormat()
{
    resetFormat();
 
    // can't check anything in an empty buffer
    if (pictb.size() == 0 || pictb.isOpen())
        return false;
 
    pictb.open(QIODevice::ReadOnly);                        // open buffer device
    QDataStream s;
    s.setDevice(&pictb);                        // attach data stream to buffer
 
    char mf_id[4];                                // picture header tag
    s.readRawData(mf_id, 4);                        // read actual tag
    int bufSize = pictb.buffer().size();
    if (memcmp(mf_id, qt_mfhdr_tag, 4) != 0 || bufSize < 12) {   // wrong header id or size
        qWarning("QPicturePaintEngine::checkFormat: Incorrect header");
        pictb.close();
        return false;
    }
 
    int cs_start = sizeof(quint32);                // pos of checksum word
    int data_start = cs_start + sizeof(quint16);
    quint16 cs,ccs;
    const QByteArray buf = pictb.buffer();        // pointer to data
 
    s >> cs;                                // read checksum
    ccs = (quint16) qChecksum(QByteArrayView(buf.constData() + data_start, buf.size() - data_start));
    if (ccs != cs) {
        qWarning("QPicturePaintEngine::checkFormat: Invalid checksum %x, %x expected",
                  ccs, cs);
        pictb.close();
        return false;
    }
 
    quint16 major, minor;
    s >> major >> minor;                        // read version number
    if (major > mfhdr_maj) {                // new, incompatible version
        qWarning("QPicturePaintEngine::checkFormat: Incompatible version %d.%d",
                  major, minor);
        pictb.close();
        return false;
    }
    s.setVersion(major != 4 ? major : 3);
 
    quint8  c, clen;
    s >> c >> clen;
    if (c == QPicturePrivate::PdcBegin) {
        if (!(major >= 1 && major <= 3)) {
            qint32 l, t, w, h;
            s >> l >> t >> w >> h;
            brect = QRect(l, t, w, h);
        }
    } else {
        qWarning("QPicturePaintEngine::checkFormat: Format error");
        pictb.close();
        return false;
    }
    pictb.close();
 
    formatOk = true;                        // picture seems to be ok
    formatMajor = major;
    formatMinor = minor;
    return true;
}
 
QPaintEngine *QPicture::paintEngine() const
{
    if (!d_func()->paintEngine)
        const_cast<QPicture*>(this)->d_func()->paintEngine.reset(new QPicturePaintEngine);
    return d_func()->paintEngine.data();
}
 
/*****************************************************************************
  QPicture stream functions
 *****************************************************************************/
 
#ifndef QT_NO_DATASTREAM
QDataStream &operator<<(QDataStream &s, const QPicture &r)
{
    quint32 size = r.d_func()->pictb.buffer().size();
    s << size;
    // null picture ?
    if (size == 0)
        return s;
    // just write the whole buffer to the stream
    s.writeRawData (r.d_func()->pictb.buffer(), r.d_func()->pictb.buffer().size());
    return s;
}
 
QDataStream &operator>>(QDataStream &s, QPicture &r)
{
    QDataStream sr;
 
    // "init"; this code is similar to the beginning of QPicture::cmd()
    sr.setDevice(&r.d_func()->pictb);
    sr.setVersion(r.d_func()->formatMajor);
    quint32 len;
    s >> len;
    QByteArray data;
    if (len > 0) {
        data.resize(len);
        s.readRawData(data.data(), len);
    }
 
    r.d_func()->pictb.setData(data);
    r.d_func()->resetFormat();
    return s;
}
#endif // QT_NO_DATASTREAM
 
QT_END_NAMESPACE
 
#endif // QT_NO_PICTURE