How very pretty. I had questions so I found this supply list for making one from the Rio Grande Valley Quilt Guild & yes, you use whatever fabric you like & you waterproof it when it's completed. Also, you use an umbrella frame. Looks like fun & would be beautiful in batiks.
https://www.rgvqg.com/uploads/1/2/4/...ella_class.pdf
https://www.rgvqg.com/programs.html