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Thread: How to scroll scanline image data from the left to the right

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    Smile How to scroll scanline image data from the left to the right

    Hi folks

    Can anyone give me some tips on the best way to scroll image data across the screen from the left side of the screen to the right. I can currently draw image data top down using a qgraphicsscene and setting a label with each scanline i read and then calling scroll, but i need to draw vertically from left to right. The image data needs to be built off screen then as more lines are read i need to start scrolling it across the display untill its complete, then make it scroll off the right side of the display. Do i need to rotate the matrix to draw vertically or just swap my x,y cordinants? Also would a QAnimation and Qtimeline be good for the scrolling or would opengl be better as far as speed and looking smooth? Thanks for any help

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    Default Re: How to scroll scanline image data from the left to the right


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    Default Re: How to scroll scanline image data from the left to the right

    You want to scroll the image or move its data?

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    Question Re: How to scroll scanline image data from the left to the right

    I need to scroll the image itself. The image data is received over a socket. The image data is just an array with the pixel values and dimensions, as 16bit bmp. I will get probably 10 lines or so on each payload and i need to append this data to a qimage and begin scrolling it onto the screen as the data is recieved from the left side, once the image is completely built i need it to continue and move across the display till it goes off the display on the right side. Im not sure if qanimation will look smooth enough, and i cant have it flickering but still needs to be somewhat fast. Also wondering if bitblt in a paintevent should be used for this. Thanks

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