Is there a tool or converter to make some of the cool round Sisyphus patterns work for a square table?
You can import the thr files from sisyphus into sandify and then export them to any table.
As for automatically converting the shape of a circle to a square, nope. But it looks good to have the circular pattern in the middle of a square table.
Sandify is open source. But I don’t own the copyrights on any patterns made in it. The patterns themselves are owned by the people who create them. The ones made by sisyphus industries are owned by them. Unless they give you permission to use them (with a license like an open source one), you can’t use them.
That annoying bit of legalese aside, many many patterns are available.