Silverlight Project -Expression Blend
Silverlight2 does not currently support any form of bitmap effects. A workaround for adding bitmap effects to any element of your Silverlight application, such as a shadow shadow copy, you would have to manually create the shadow of the UI element and export it as an image and place it in the Silverlight application as an image.
If you are using Expression Design, all you have to do is copy and paste it into Expression Blend (make sure your clipboard is set to Silverlight XAML) and it will automatically convert the bitmapeffect to a separate image.
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This is now possible in Silverlight 3, which was submitted in beta a few months ago. WPF BitmapEffects were considered too slow to wrap, but there are effects. Two are built in: BlurEffect and DropShadowEffect. In addition, you can write your own pixel shaders in HLSL just like you can in WPF to achieve a wide variety of effects.
Some links: Expression Blend 3 Preview: http://www.microsoft.com/downloads/details.aspx?FamilyID=A04AA0AE-87BE-4201-A65E-E792859122FC&displaylang=en
Some ShaderEffects that run in WPF or Silverlight: http://www.codeplex.com/wpffx/
Silverlight 3 Beta: http://silverlight.net/getstarted/silverlight3/default.aspx
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