Imaginary Skip Rope

26th Jan 2015

Creating Digital Play at the Global Game Jam (GGJ15) with the Lincoln Games Research Group.

We have just participated in Global Game Jam 15. We decided to create an Imaginary Skip Rope game.

We think this is interesting because unlike traditional Skip Rope our game is a little more forgiving - there is a relatively low risk of injury since you can jump to any height, we could introduce dynamic balancing to give new players an advantage, you could play it remotely over the Internet, there's no right and wrong answer (you're not out when you get hit), and best of all, you use your imagination.

We simulate the rope using verlet integration - so the game is authentically reproducing a rope behind the scenes. Players can collide with the rope when it is at the low point in the travel, unless of course they jump.

We integrate to find the position of the blue/red controllers which we use to spin the rope. To detect when the central players have jumped we measure the magnitude of the movement of the white controllers.

Players are given a "rolling start" by letting the end players "arm" the PlayStation Move controllers once players are ready. Each game lasts only twenty seconds - the best player is indicated by giving them a green light, the other, a red light.

What Do We Do Now? was the theme to GGJ15. As players on both sides of the rope - we become a little bit of the game engine - what do we do now? Do we play nice or do we go fast?

This video below shows the verlet integration we used to represent the rope - look for the black line representing the rope. (Scoring a little broke on this one but fixed in the committed version).

And a close up of the physics:

Programmed by Gavin Wood (Newcastle University), and John Shearer (Lincoln University) who was also facilitating the Game Jam.

Thanks to Amber van de Rest and Nick Harbour for playtesting our game. http://thp.io/2010/psmove/ for their PS Move API, and http://games.lincoln.ac.uk for hosting the event.

More games at Lincoln's GGJ page