Where does their right to protest end and my right to use the park if I so desire start?

A public space must remain public, it isn't public if someone is camping out there, it becomes private to that structure.

The protesters are also blocking Broadway, a public thoroughfare. They are not allowed to impede the movement of other folks.

Protesters are fighting with the police. I hope the cops knock some heads.

Typical liberal behavior, rights are for liberals but not for anyone else. The liberals treat the 1st amendment the same way when they shout down conservative speakers.