Okay, I can see that a preview would go a long way toward
making the dialog more usable. I looked over the relevant code,
though, and I'm not sure it would be very easy to set one
up. Previewing libart stroking wouldn't be very hard, because
basically all you need is a set of tiles to do the stroking on.
Previewing paint tool stroking would be more problematic:
it requires either an attached drawable, or massive code
changes. So, as far as I can see, the only way to do it without
massive rewriting would be to create a new temporary layer,
attach it to the image, render the preview onto it, transfer
the preview to the dialog, then remove the temporary layer.
That wouldn't be hard to do, but it seems a bit, um, baroque.
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