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Re: Rescale and copy area of source image into an area of dest image [message #14554 is a reply to message #14547]

Mon, 03 March 2008 17:52

mdelfede
Messages: 1307
Registered: September 2007

Ultimate Contributor

well, partly solved... the bug was not here... for others interested in using Image and Imagebuffer, beware :

ImageBuffer buf;
Draw d = ........
...........
...........
d.DrawImage(buf, .....)

will *not* work, or better, it'll work ONCE.
DrawImage expects an Image& parameter, so buf is converted on the fly onto Image object, loosing its content due to destroy-on-copy behaviour.
The correct code is :

ImageBuffer buf;
Draw d = ........
...........
...........
Image img = buf;
d.DrawImage(img, .....)
buf = img;

quite un-intuitive, indeed. It would be much better to have a different version of DrawImage with an ImageBuffer & as first parameter. Also, allowing such automatic type conversion on objects that have the destroy-on-copy semantics can lead to subtle bugs...

Ciao

Max

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