Paint shadow inside an QImage or QGraphicsEffect Shadow... html page doc

patrik08

How can i make a shadow allround one page 4-6 pixel?
QGraphicsEffect is only for widged..?

/// Background image for 1 html page in subclass QAbstractScrollArea A4 or other
static QImage onepageimage( const QRectF big , qreal substract ) {
  QImage qImage(big.size().width() ,big.size().height(),QImage::Format_RGB32);
  qImage.fill(Qt::blue);
  QPainter *p = new QPainter();
  p->begin(&qImage);
  p->setPen(QPen(Qt::black,5, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin)); /// shadow
  p->setBrush(Qt::white);
  /// p->setPen(Qt::NoPen);
  p->drawRect(QRectF(0,0,big.size().width() - substract , big.size().height() - substract ));
  p->save();
  bool bEnd = p->end();
  if (bEnd) {
      return qImage;
    } else {
      return QImage();
    }
}

mrjj

@patrik08 said in Paint shadow inside an QImage or QGraphicsEffect Shadow... html page doc:

QGraphicsEffect

Is for all classes that have setGraphicsEffect
You can cheat
https://stackoverflow.com/questions/3903223/qt4-how-to-blur-qpixmap-image

the posts at the end if for Qt5+

patrik08

Tanks ....
Compiler accept only this way ...... ;-)

#ifdef QT_NO_GRAPHICSEFFECT
QImage applyEffectToPics(QImage src, QGraphicsEffect *effect, int extent = 0)
{
    if(src.isNull()) return QImage();   //No need to do anything else!
    if(!effect) return src;             //No need to do anything else!
    QGraphicsScene scene;
    QGraphicsPixmapItem item;
    item.setPixmap(QPixmap::fromImage(src));
    item.setGraphicsEffect(effect);
    scene.addItem(&item);
    QImage res(src.size()+QSize(extent*2, extent*2), QImage::Format_ARGB32);
    res.fill(Qt::transparent);
    QPainter ptr(&res);
    scene.render(&ptr, QRectF(), QRectF( -extent, -extent, src.width()+extent*2, src.height()+extent*2 ) );
    return res;
}
#endif