What is a snail shower?
https://www.google.com/search?q=snail+shower&client=fire…
Here’s mostly classic snail showers. You can accomplish the same idea with square walls rather than the fancy curves.
The main idea is that the spray from the shower can’t get out, you don’t need a shower curtain, and the floor is flat or only slightly sloped. With beefier walls (and more room) you can accommodate hand rails or a wheelchair or a fold out seat.
–Peter