Button Basher

Wilhelm Sanke sanke at hrz.uni-kassel.de
Thu Feb 12 14:08:55 EST 2009

On Wed Feb 11, 2009, Richmond Mathewson geradamas at yahoo.com wrote:

> I have found the nature of the earlier problem I wrote about:
> When a template image is chosen for an odd-shaped button, unless the
> card is exited and returned to, the alpha-data from that image is not 
> recognised.
> And, if you understand what that means and why it happens you are
> a better person than me :)
> However, this has meant that I got BADLY DISTRACTED for about 3 days
> remaking PNG images in GIMP - when the whole problem resided with
> Runtime Revolution; Generalised Gnashing of Teeth!
> sincerely, Richmond Mathewson.


I have come across similar or even the same problems. I quote here a 
part from the text of the "discussion" on card "Prefabricated Masks" of 
my sample stacks "MoreAboutMasks" and "MoreAboutMasksRev3":

> "A final observation concerning the creation of masks inside 
> Revolution and using the "import snapshot" format:
> If the resulting mask image is not first saved as an external file and 
> then imported again, meaning if it remains as freshly created inside a 
> stack or was just copied from another mask-producing stack, then this 
> mask image will have a different quality, which we might call a "pre-PNG".
> Pre-PNGs behave somewhat differently than normal PNGs: You cannot 
> transfer its alphamask to the image-to-be-masked when the pre-PNG is 
> hidden, at least not several times with resizing. After you have 
> resized a pre-PNG during the masking process, you might find that it 
> is suddenly "empty", but it can be restored when you copy and paste it 
> (it then appears in its original size and shape).
> A workaround to overcome this problem is to store the mask in a custom 
> property of its own and then to "initialize" the mask each time before 
> it is used in the calling script:
> "put the CPimg of img "transition" into img "transition""
> But of course you can easily convert a pre-PNG to a full PNG by saving 
> the image as an external file."--

The new "shapes" card of your "BB alpha" stack seems to work without 
problems here (Windows XP and Rev 3.0). I see you have achieved the 
functionality you intended, and you could apparently make some use of 
the support offered in the discussion on this empathic list.

Once you haved reached this stage of development, you could now proceed 
to fine-tune your scripts. There seems to be some room to weed out 
I had a look at the script of button "EXPORT BUTTON IMAGES" with its 
about 40 lines of script. You could reduce that script to only 20 lines 
without influencing or changing the any of results when running the script.

If you are interested in details, I could contact you off-list, but 
anyhow your script - as it is - provides the functionality you have 

Best regards,

Wilhelm Sanke

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