As of now, none of the blocks have functionality, so it is not a usable physics engine yet, rather one in development.
I know that there are other physics engines and collaborations of such and that I should coalesce makes into an existing one rather than start entirely new works from scratch. But at the end of the day, the other physics engines I know are just forgotten. I felt like starting a new one - this, and I promise I will not forget about it. Additionally, my other collaboration, a UI engine, was paused until Snap! 12.
As with my UI engine, the goal of this collaboration is to hopefully be a physics engine that is full-fledged and others can enjoy using it for free!
BTW, I want to add a flag which makes it so that all sprites can automatically step in the physics engine (using a Turtle sprite stepping the rest of the sprites). May I?