qwindowsurface_raster.cpp File Reference

#include <qdebug.h>
#include <qglobal.h>
#include <qlibrary.h>
#include <qt_windows.h>
#include <QtGui/qpaintdevice.h>
#include <QtGui/qwidget.h>
#include "private/qwindowsurface_raster_p.h"
#include "private/qnativeimage_p.h"
#include "private/qwidget_p.h"
#include "private/qpixmap_x11_p.h"
#include "private/qt_x11_p.h"
#include "qx11info_x11.h"
#include "private/qdrawhelper_p.h"
#include <private/qt_cocoa_helpers_mac_p.h>
#include <QMainWindow>
#include <private/qmainwindowlayout_p.h>
#include <QToolBar>

Go to the source code of this file.

Classes
class	QRasterWindowSurfacePrivate

Functions
void	qt_scrollRectInImage (QImage &img, const QRect &rect, const QPoint &offset)

Function Documentation

qt_scrollRectInImage()

void qt_scrollRectInImage	(	QImage &	img,
		const QRect &	rect,
		const QPoint &	offset
	)

Definition at line 345 of file qwindowsurface.cpp.

Referenced by QRasterWindowSurface::scroll(), and QRasterWindowSurface::setGeometry().

{
    // make sure we don't detach
    uchar *mem = const_cast<uchar*>(const_cast<const QImage &>(img).bits());

    int lineskip = img.bytesPerLine();
    int depth = img.depth() >> 3;

    const QRect imageRect(0, 0, img.width(), img.height());
    const QRect r = rect & imageRect & imageRect.translated(-offset);
    const QPoint p = rect.topLeft() + offset;

    if (r.isEmpty())
        return;

    const uchar *src;
    uchar *dest;

    if (r.top() < p.y()) {
        src = mem + r.bottom() * lineskip + r.left() * depth;
        dest = mem + (p.y() + r.height() - 1) * lineskip + p.x() * depth;
        lineskip = -lineskip;
    } else {
        src = mem + r.top() * lineskip + r.left() * depth;
        dest = mem + p.y() * lineskip + p.x() * depth;
    }

    const int w = r.width();
    int h = r.height();
    const int bytes = w * depth;

    // overlapping segments?
    if (offset.y() == 0 && qAbs(offset.x()) < w) {
        do {
            ::memmove(dest, src, bytes);
            dest += lineskip;
            src += lineskip;
        } while (--h);
    } else {
        do {
            ::memcpy(dest, src, bytes);
            dest += lineskip;
            src += lineskip;
        } while (--h);
    }
}