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Hello newsgroup!

I am trying to reset a specific area in a BufferedImage that has been
set up using an Alpha chanel (TYPE_INT_ARGB). The idea is that I have
to refresh a certain area an therefore I want to clear it before I
redraw it. Currently I am using the following code:

In the constructor:
this.image = new BufferedImage(this.getWidth(),
this.getHeight(), BufferedImage.TYPE_INT_ARGB);
this.dirtyHack = new BufferedImage(this.getWidth(),
this.getHeight(), BufferedImage.TYPE_INT_ARGB);

In the paintComponent method:
image.setData(dirtyHack.getData(bounds));

This works, but it uses a lot of memory. Is there a cheaper way of
doing this?

Thanks for your help!

charlym wrote:
> I am trying to reset a specific area in a BufferedImage
[...]

> This works, but it uses a lot of memory. Is there a cheaper way of
> doing this?

image.getGraphics().clearRect(...);

Check the API doc for details.

/Thomas
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Thomas & the rest of the newsgroup,

I tried this but it does not do what I expected. I want the rectangle
to be totally transparent. clearRect fills the rectangle with the
backgroundcolor I also tried to change the color using a
transparent color (new Color(0,0,0,0)) but it did not help either.

Any other ideas?

"charlym" <> wrote in message
news: oups.com...
> Thomas & the rest of the newsgroup,
>
> I tried this but it does not do what I expected. I want the rectangle
> to be totally transparent. clearRect fills the rectangle with the
> backgroundcolor I also tried to change the color using a
> transparent color (new Color(0,0,0,0)) but it did not help either.
>
> Any other ideas?

From the javadocs:

<quote>
Beginning with Java 1.1, the background color of offscreen images may be
system dependent. Applications should use setColor followed by fillRect to
ensure that an offscreen image is cleared to a specific color.
</quote>

Did you try that?

- Oliver