GLSL/Shiva style Filter Preview

[Thomas Burdick]

One of the things I never really liked about the way the glsl plugin
worked, was the dialog, and especially the preview.

I almost feel like the preview should be shown on the canvas itself.

Is this a bad idea? Can it be done easily? How would I do it if so?

I suppose Cyrille's Shiva  and this GLSL plugin should probably
preview in a similar manner since they provide similar functionality.

Your thoughts?

-Tom