How to do moveable transparent region.

Hello,

I'm fairly new to WPF and am wondering if anyone can give me some
pointers of how to implement the following:

I have a background image and a hidden image superimposed on each other,
but would like to have the effect of a draggable "lens" that as the user
moves it about over the background image, it displays the hidden image
directly underneath it.

Could someone point me in a direction for this?

Thanks

The draggable "lens" should use a VisualBrush. That VisualBrush should be
mapped to your "hidden" image.

"bsmucker" wrote:

> Hello,
>
> I'm fairly new to WPF and am wondering if anyone can give me some
> pointers of how to implement the following:
>
> I have a background image and a hidden image superimposed on each other,
> but would like to have the effect of a draggable "lens" that as the user
> moves it about over the background image, it displays the hidden image
> directly underneath it.
>
> Could someone point me in a direction for this?
>
> Thanks
>

The draggable "lens" should use a VisualBrush. That VisualBrush should be
mapped to your "hidden" image.

"bsmucker" wrote:

> Hello,
>
> I'm fairly new to WPF and am wondering if anyone can give me some
> pointers of how to implement the following:
>
> I have a background image and a hidden image superimposed on each other,
> but would like to have the effect of a draggable "lens" that as the user
> moves it about over the background image, it displays the hidden image
> directly underneath it.
>
> Could someone point me in a direction for this?
>
> Thanks
>

That certainly works, though an alternative is to create a DrawingBrush to
use as an OpacityMask on the background Image which has a transparent hole
in the middle. This will "punch" a hole through the Element with which it
is associated to reveal whatever's behind.

-Adam Smith [MS]

"GeneW" <GeneW@discussions.microsoft.com> wrote in message
news:6B7DE049-08E8-4340-8858-C69FF77E4B89@microsoft.com...
> The draggable "lens" should use a VisualBrush. That VisualBrush should be
> mapped to your "hidden" image.
>
> "bsmucker" wrote:
>
>> Hello,
>>
>> I'm fairly new to WPF and am wondering if anyone can give me some
>> pointers of how to implement the following:
>>
>> I have a background image and a hidden image superimposed on each other,
>> but would like to have the effect of a draggable "lens" that as the user
>> moves it about over the background image, it displays the hidden image
>> directly underneath it.
>>
>> Could someone point me in a direction for this?
>>
>> Thanks
>>

That certainly works, though an alternative is to create a DrawingBrush to
use as an OpacityMask on the background Image which has a transparent hole
in the middle. This will "punch" a hole through the Element with which it
is associated to reveal whatever's behind.

-Adam Smith [MS]

"GeneW" <GeneW@discussions.microsoft.com> wrote in message
news:6B7DE049-08E8-4340-8858-C69FF77E4B89@microsoft.com...
> The draggable "lens" should use a VisualBrush. That VisualBrush should be
> mapped to your "hidden" image.
>
> "bsmucker" wrote:
>
>> Hello,
>>
>> I'm fairly new to WPF and am wondering if anyone can give me some
>> pointers of how to implement the following:
>>
>> I have a background image and a hidden image superimposed on each other,
>> but would like to have the effect of a draggable "lens" that as the user
>> moves it about over the background image, it displays the hidden image
>> directly underneath it.
>>
>> Could someone point me in a direction for this?
>>
>> Thanks
>>