Daryl,
Yes it, would be good to fix this. If I recall correctly, the status of
alpha values for basic graphic file formats are:
JPEG: no alpha information stored
GIF: 1 bit per pixel of alpha information
PNG: 8 bits per pixel of alpha information
So storing 8-bit alpha values will use up a little more memory in the case
of JPEG and GIF images, but it's probably not a big deal. It might be best
to make the default TYPE_INT_ARGB, and then provide a constructor option
that lets you set it to TYPE_INT_RGB in case someone wants to conserve
memory.
If you do want add these alpha values, then you should start with a demo
program that shows how different alpha values will be displayed in
TheMatrix. Indeed, a set of carefully created examples will probably help
explain and clarify these tricky alpha value issues.
I'll add the alpha values issue as a feature for you ...
Toby
On 5/14/05 9:55 AM, "Daryl Van Humbeck" <dva...@sf...> wrote:
> I just realized that TheMatrix isn't saving Alpha values that it's given.
>
> When the BufferedImage is created in utils.Utilities.java, it's created
> with type TYPE_INT_RGB, which doesn't save Alpha values, instead of
> TYPE_INT_ARGB, which does.
>
> Also, to create a Color object from an RGBA packed integer, using new
> Color(int) ignores the Alpha value, when you use new Color(int, boolean
> true) it actually copies it.
>
> Another thing is when you're drawing an image with transparent pixels
> onto another image (see utils.Utilites.java, method BufferedImage
> makeBufferedImage(Image image, int image_type)) it doesn't copy the
> Alpha values, it just blends the pixels with alpha values with the color
> that's already there (usually black), which probably isn't what we want,
> is it?
>
> I found this out by reading the JavaDocs, looking for information for
> another project I'm working on (if you want to know, NQL, Not Quite Liero).
>
> If you want these problems fixed, I think I'd like to volunteer (unless
> you think I'm working on too much already).
>
> Daryl.
>
--
Dr. Toby Donaldson
School of Computing Science
Simon Fraser University
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