diff options
Diffstat (limited to 'src/gui/image/qpixmap.cpp')
-rw-r--r-- | src/gui/image/qpixmap.cpp | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/src/gui/image/qpixmap.cpp b/src/gui/image/qpixmap.cpp index 8684a1b..e563fc9 100644 --- a/src/gui/image/qpixmap.cpp +++ b/src/gui/image/qpixmap.cpp @@ -379,6 +379,56 @@ QPixmap QPixmap::copy(const QRect &rect) const } /*! + \fn QPixmap::scroll(int dx, int dy, int x, int y, int width, int height, QRegion *exposed) + + This convenience function is equivalent to calling QPixmap::scroll(\a dx, + \a dy, QRect(\a x, \a y, \a width, \a height), \a exposed). + + \sa QWidget::scroll(), QGraphicsItem::scroll() +*/ + +/*! + Scrolls the area \a rect of this pixmap by (\a dx, \a dy). The exposed + region is left unchanged. You can optionally pass a pointer to an empty + QRegion to get the region that is \a exposed by the scroll operation. + + \snippet doc/src/snippets/code/src_gui_image_qpixmap.cpp 2 + + You cannot scroll while there is an active painter on the pixmap. + + \sa QWidget::scroll(), QGraphicsItem::scroll() +*/ +void QPixmap::scroll(int dx, int dy, const QRect &rect, QRegion *exposed) +{ + if (isNull() || (dx == 0 && dy == 0)) + return; + QRect dest = rect & this->rect(); + QRect src = dest.translated(-dx, -dy) & dest; + if (src.isEmpty()) { + if (exposed) + *exposed += dest; + return; + } + + detach(); + + if (!data->scroll(dx, dy, src)) { + // Fallback + QPixmap pix = *this; + QPainter painter(&pix); + painter.setCompositionMode(QPainter::CompositionMode_Source); + painter.drawPixmap(src.translated(dx, dy), *this, src); + painter.end(); + *this = pix; + } + + if (exposed) { + *exposed += dest; + *exposed -= src.translated(dx, dy); + } +} + +/*! Assigns the given \a pixmap to this pixmap and returns a reference to this pixmap. |