void Shadow::draw(QPainter* painter)
{
// if nothing to show outside the item, just draw source
if ((blurRadius() + distance()) <= 0) {
drawSource(painter);
return;
}
PixmapPadMode mode = QGraphicsEffect::PadToEffectiveBoundingRect;
QPoint offset;
const QPixmap px = sourcePixmap(Qt::DeviceCoordinates, &offset, mode);
// return if no source
if (px.isNull())
return;
// save world transform
QTransform restoreTransform = painter->worldTransform();
painter->setWorldTransform(QTransform());
// Calculate size for the background image
QSize szi(px.size().width() + 2 * distance(), px.size().height() + 2 * distance());
QImage tmp(szi, QImage::Format_ARGB32_Premultiplied);
QPixmap scaled = px.scaled(szi);
tmp.fill(0);
QPainter tmpPainter(&tmp);
tmpPainter.setCompositionMode(QPainter::CompositionMode_Source);
tmpPainter.drawPixmap(QPointF(-distance(), -distance()), scaled);
tmpPainter.end();
// blur the alpha channel
QImage blurred(tmp.size(), QImage::Format_ARGB32_Premultiplied);
blurred.fill(0);
QPainter blurPainter(&blurred);
qt_blurImage(&blurPainter, tmp, blurRadius(), false, true);
blurPainter.end();
tmp = blurred;
// blacken the image...
tmpPainter.begin(&tmp);
tmpPainter.setCompositionMode(QPainter::CompositionMode_SourceIn);
tmpPainter.fillRect(tmp.rect(), color());
tmpPainter.end();
// draw the blurred shadow...
painter->drawImage(offset, tmp);
// draw the actual pixmap...
painter->drawPixmap(offset, px, QRectF());
// restore world transform
painter->setWorldTransform(restoreTransform);
}
QT_END_NAMESPACE
void ShadowEffect::draw(QPainter* painter){
if((blurRadius() + distance()) <= 0){
drawSource(painter);
return;
}
PixmapPadMode mode = QGraphicsEffect::PadToEffectiveBoundingRect;
QPoint offset;
const QPixmap px = sourcePixmap(Qt::DeviceCoordinates, &offset, mode);
if(px.isNull())
return;
QTransform restoreTransform = painter->worldTransform();
painter->setWorldTransform(QTransform());
QSize szi(px.size().width() + 2 * distance(), px.size().height() + 2 * distance());
QImage tmp(szi, QImage::Format_ARGB32_Premultiplied);
QPixmap scaled = px.scaled(szi);
tmp.fill(0);
QPainter tmpPainter(&tmp);
tmpPainter.setCompositionMode(QPainter::CompositionMode_Source);
tmpPainter.drawPixmap(QPointF(-distance(), -distance()), scaled);
tmpPainter.end();
QImage blurred(tmp.size(), QImage::Format_ARGB32_Premultiplied);
blurred.fill(0);
QPainter blurPainter(&blurred);
qt_blurImage(&blurPainter, tmp, blurRadius(), false, true);
blurPainter.end();
tmp = blurred;
tmpPainter.begin(&tmp);
tmpPainter.setCompositionMode(QPainter::CompositionMode_SourceIn);
tmpPainter.fillRect(tmp.rect(), color());
tmpPainter.end();
painter->drawImage(offset, tmp);
painter->drawPixmap(offset, px, QRectF());
painter->setWorldTransform(restoreTransform);
}
