Try drawing something other than an image. I have a hunch the alpha-
bitblt is wrong ...
Btw, which platform are you on? Which VM?
- Bert -
On Apr 23, 2007, at 9:32 , Steven Greenberg wrote:
Following Bert's advice, I see that HaloMorph overrides
#drawSubmorphsOn: and calls its Canvas using
asAlphaBlendingCanvas. That seems like a good place to start.
I tried subclassing ImageMorph and adding this method:
drawOn: aCanvas
^ super drawOn: (aCanvas asAlphaBlendingCanvas: alphaValue).
Unfortunately, it didn't display anything at all. I tried alpha
values of 0.5 and 1.0. If I remove the alpha blending stuff, and
simply call:
^ super drawOn: aCanvas.
it works like a normal ImageMorph, so at least I know it isn't
broken someplace else.
Any suggestions on how to get asAlphaBlendingCanvas to blend some
alphas?
On 4/23/07, Steven Greenberg <[EMAIL PROTECTED]> wrote:
Thanks for the pointer! I didn't try that code in the workspace,
but if you enable "haloTransitions" using the Preferences browser
then the halos fade in and out.
Thanks,
Steve
On 4/22/07, Bert Freudenberg <[EMAIL PROTECTED] > wrote:
On Apr 23, 2007, at 0:44 , Steven Greenberg wrote:
> I have a PNG image that I'd like to display fading out. I tried
> the BitBlt method suggested by "Team RAR" to fade the image, but I
> can't make it work.
>
> The image loads properly from a file and displays fine as an
> ImageMorph. I have been able to use a TransformationMorph to
> rotate and scale it, and PNG transparency is working properly.
>
> Is the "Team RAR" BitBlt method the only way, or are there
> alternatives?
>
> I'm running a 3.9 image, and my display depth is set to 32 bits.
>
Normally you would just use an alpha-blending canvas. See HaloMorph
fadeIn/fadeOut and draw methods. To try those halos, enable this:
Preferences enable: #haloTransitions
Now when I tried then the halo icons do not actually show until alpha
is one. No idea why that is.
- Bert -
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