How to shift pixels of a pixmap efficient in Qt4

Posted by stanleyxu2005 on Stack Overflow See other posts from Stack Overflow or by stanleyxu2005
Published on 2010-04-26T08:29:50Z Indexed on 2010/04/26 8:33 UTC
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Filed under:

qt

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pixmap

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Performance

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marquee

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text

Hello,

I have implemented a marquee text widget using Qt4. I painted the text content onto a pixmap first. And then paint a portion of this pixmap onto a paint device by calling painter.drawTiledPixmap(offsetX, offsetY, myPixmap)

My Imagination is that, Qt will fill the whole marquee text rectangle with the content from myPixmap.

Is there a ever faster way, to shift all existing content to left by 1px and than fill the newly exposed 1px wide and N-px high area with the content from myPixmap?

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