Image Display Issues on Win XP

J. Landman Gay jacque at hyperactivesw.com
Thu Dec 22 17:33:52 EST 2005


Rob Cozens wrote:
> Bill, Jacque, er al:
> 
> I have been able to achieve acceptable performance by changing the Art 
> Card design so the thumbnails are truly thumbnail imageData that 
> hide/show the full-resolution images and the Photo Index Card design 
> from buttons to thumbnail images.  I also set alwaysBuffer to false for 
> all images...and masked the "jerky" display by adding a visual effect to 
> card-to-card navigation.  All images still reside in the [88 MB] stack 
> file, but the only time an image is resized is when the viewer does it 
> via a "Zoom Bar."
> 
> One mystery arose during the redesign:  Under what conditions will Rev 
> change the loc of an image when its height and/or width is changed?
> 
> This code worked in the old design:
> 
>     set the height of image targetImage to x
>     set the width of image targetImage to trunc(x*1.5)
> 
> with expansion/contraction from the original loc of targetImage.
> 
> Now I have to script:
> 
>     put the loc of image targetImage into imageLoc
>     set the height of image targetImage to x
>     set the width of image targetImage to trunc(x*1.5)
>     set the loc of image targetImage to imageLoc
> 
> or the image moves to a new loc.
> 
> What could cause this...on WinXP & MacOSX?

I noticed the same thing on something I'm working with right now. Images 
  always resize around the center location, so you'd think they would 
always stay put. But I think what's happening is that if the new 
dimension isn't evenly divisible by 2, the engine has to put the extra 
pixel on one side or the other. If you resize by uneven amounts enough 
times, the location will shift.

Don't ask me why it didn't happen in your old design. Haven't a clue.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com



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