Projected Lineriders cars follow lines that people draw on the surface with pens, speeding up and slowing down according to a visual annotation language. The cars skid and crash and jump over obstacles like hands, bridging the space between the physical and virtual. The game is open ended, nurturing peoples' own creativity and imagination as they strive to create the perfect track.

Lineriders features 3D toy cars that are projected onto an infrared light box. Players create their own tracks by drawing lines using whiteboard markers. By using different visual patterns, they can control when cars accelerate, break and launch over jumps. Unlike traditional track car toys, players are not limited by the available track. The silhouette image of the track is recored by an infrared camera overhead and car logic updated. Infrared is used over visible light to record the track to avoid feedback from the projector.

Lineriders was a collaborative between Philip Worthington and William Denniss. Philip developed the lineriders concept as part of a Hot Wheels design competition and created a 2D prototype which was showed at the Mattel headquarters in LA. In May 2005, Philip contacted William to help take the game into a three dimensional physics simulation engine. Forty days later the game was displayed at London Royal College of Art interaction design show, in London. The final product ran on a dual-core G5 Mac, used an infrared camera, colour project and custom infrared light box. Not exactly cheaper than plastic track cars, but that wasn't really the point.



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Promotional Postcard

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At the Show


Debugging Mode Screen Captures


Technology Used

Lineriders tallied the following technologies:

3D Rendering - Xith3D
Physics Simulation - Odejava (a java port of ODE)
Image Processing - Processing
Programming Environment - Java