Yes, it's called 3D Foam. It typically increases the stitch count vs if it were flat. Not all designs work with it. Very thin and very wide don't work as nice. The foam needs to be close in color to the thread color it's under since some of the foam make peek through the thread. Make sure to use a digitizer who can provide samples of previous work. Usually need to slightly spray tack the foam to the cap after it's done the outline stich, similar to an applique process. The needles might gum up–you can use baby wipes to clean the needles and needle area.
