how to use bitBlt in QT 3

[garry_3peace]

I have try to use bitBlt but it seems failed. the "buffer" is null. Is there any problem with the code?

QImage hehe("f_rain1m_e5bff66.jpg" );
    QImage buffer;
    bitBlt(&buffer, 4, 5 , &hehe, lstBox->x(), lstBox->y(), lstBox->width(), lstBox->height(), CopyROP);
    lstBox->setPaletteBackgroundPixmap(buffer);
    qWarning("%d",buffer.isNull());

QImage hehe("f_rain1m_e5bff66.jpg" );
    QImage buffer;
    bitBlt(&buffer, 4, 5 , &hehe, lstBox->x(), lstBox->y(), lstBox->width(), lstBox->height(), CopyROP);
    lstBox->setPaletteBackgroundPixmap(buffer);
    qWarning("%d",buffer.isNull());

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NB:
The result in terminal is 1 which mean the buffer is still null, right?

[punit.doshi.85]

hi, did u got the code working ??
can u please send me d code pls, i too need it for seeing the blitting thing n it mite save much of my time. i am using Qt 4.4

thanks in advance,
Punit.

[jacek]

QImage buffer;

You create a null image. Give it some size.

[garry_3peace]

Hm... I see, Ok.. I'll try it later...

[garry_3peace]

Hm... still failed..

I declared it like this:

QImage buffer(200,200, 1); //right?

[jacek]

QImage buffer(200,200, 1); //right?

Why "1"? Shouldn't it be 32?

bitBlt(&buffer, 4, 5 , &hehe, lstBox->x(), lstBox->y(), lstBox->width(), lstBox->height(), CopyROP);

CopyROP is from the Qt::RasterOp enum, not Qt::ImageConversionFlags. Pass 0 as the last argument, if you don't know what to put there.

What are the values of x(), y(), width() and height()?