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From: George Weis on 23 Feb 2010 14:50
Makes sense to me. I guess you'd get the same effect by looking at
two mirrors
lined up opposite each other.

As for your words of advice, it just would be nice to something in
pure java,
because the product is supposed to be run on a variety of platforms.
So,
the alternative is to say:

if we're on windows
{
use maximize.exe
}
else if we're on a Mac
{
use whatever they use
}
else if we're on Mandrake
....

that's pretty ugly too.

> Right.  If you're old enough, you might remember a common video effect
> accomplished by pointing the video camera at a monitor showing the image
> captured by the video camera.  They don't use it much these days, but it
> was all the rage in the 70's.  :)
>
> Anyway, the problem is that you are capturing the image from the screen.
>   So of course, once you display the updated scaled image on the screen,
> the next capture includes the scaled image, so that scaled portion is
> scaled again and presented again.  Every time your code recaptures the
> display, this occurs and you get a sort of "tunnel vision" effect.
>
> Depending on what you're trying to do, it's either simple to fix or not.
>   If you're trying to implement a completely general "magnifying" tool
> that will scale arbitrary regions of the computer display, you're in for
> an uphill battle, especially in Java.  You need more control over the
> rendering process than simply doing a screen capture, so that when you
> obtain an image to be scaled, it's the _original_ image, not one that
> includes your scaling.
>
> On the other hand, if you're just trying to scale stuff in your own Java
> application, that's a lot simpler if you're willing to write a custom
> component into which the drawing happens.  In your component's paint()
> method, you can use the transform features of the Graphics instance to
> scale whatever drawing you do in the component.
>
> Even there, you may run into difficulty if you want to scale not only
> your own drawing, but also how built-in Java components draw.  It's
> possible for lightweight controls you might be able to intercept the
> rendering process early enough to scale the output, but for controls
> that are based on platform/OS, forcing those to scale will be trickier,
> if possible at all.
>
> Pete

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