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RE: [JAVA2D] Alpha blending performance

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Anonymous

Hello All --

I have what is probably a simple problem to you all, but is so far
baffling me, a statistics guy doing programming. I am hoping that
someone may have actually done what I am trying to do.

At the end of some serious mathematical calculations (logistic
regression) I generate a graph in a JPanel. My problem is that I might
do this a few hundred times for a given run of the program. What I want
to do is save the contents of _each_ graph as a jpeg rather than do lots
of screen captures.

In preparation for coding I have been learning a bit about IMAGEIO,
etc., but am stumped about one aspect of my anticipated process: how do
I get the contents of a content pane into an image format?

I am assuming that I can't just cast it somehow; I am also assuming
that I cannot simply draw to an image the same way that I draw to the
content pane. (These assumptions may be wrong??)

I did run across a forum where someone said that they had not done it,
but it SHOULD work in practice and then gave a strategy for doing it.

Is there anyone who HAS done this and could offer a general strategy?
I am OK with the coding before and after the panel contents --> image
step. (Strategy much appreciated, sample code that works adored!)

References to the literature are fine also...

Thank you in advance.

-- Chris

Chris Olsen
H.S. Math / Assessment Facilitator
Educational Service Center
346 2nd Ave. SW
Cedar Rapids, IA 52404-2099

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Ken Warner

The simple answer is don't draw into the JPanel -- draw into one of Java's
image classes (Image, BufferedImage, etc.) and then draw the Image into
the JPanel. Then save the Image as a jpeg in the usual ways...

Olsen Chris wrote:
> Hello All --
>
> I have what is probably a simple problem to you all, but is so far
> baffling me, a statistics guy doing programming. I am hoping that
> someone may have actually done what I am trying to do.
>
> At the end of some serious mathematical calculations (logistic
> regression) I generate a graph in a JPanel. My problem is that I might
> do this a few hundred times for a given run of the program. What I want
> to do is save the contents of _each_ graph as a jpeg rather than do lots
> of screen captures.
>
> In preparation for coding I have been learning a bit about IMAGEIO,
> etc., but am stumped about one aspect of my anticipated process: how do
> I get the contents of a content pane into an image format?
>
> I am assuming that I can't just cast it somehow; I am also assuming
> that I cannot simply draw to an image the same way that I draw to the
> content pane. (These assumptions may be wrong??)
>
> I did run across a forum where someone said that they had not done it,
> but it SHOULD work in practice and then gave a strategy for doing it.
>
> Is there anyone who HAS done this and could offer a general strategy?
> I am OK with the coding before and after the panel contents --> image
> step. (Strategy much appreciated, sample code that works adored!)
>
> References to the literature are fine also...
>
> Thank you in advance.
>
> -- Chris
>
> Chris Olsen
> H.S. Math / Assessment Facilitator
> Educational Service Center
> 346 2nd Ave. SW
> Cedar Rapids, IA 52404-2099
>
> ===========================================================================
> To unsubscribe, send email to listserv@java.sun.com and include in the body
> of the message "signoff JAVA2D-INTEREST". For general help, send email to
> listserv@java.sun.com and include in the body of the message "help".
>
>

===========================================================================
To unsubscribe, send email to listserv@java.sun.com and include in the body
of the message "signoff JAVA2D-INTEREST". For general help, send email to
listserv@java.sun.com and include in the body of the message "help".