The Trend Is Your Friend!

Headtracking by Florian Krebs
In the installation, visitors slip through an opening in the membrane that is stretched between the projection walls. As they become part of the architectural environment their heads turn into joysticks to navigate through the virtual world. Each player is assigned one specific insect that moves over the projection area in accordance with the head movements. An optical system tracks the viewing direction and sends the data to the game computer.

Functionality
Seven cameras are attached to the ceiling above the players heads. Infrared camera remote controls (Nintendo Wii) are used. They are inexpensive and easily available in toy shops. The cameras have a resolution of 1024x768 pixels each, which is sufficient for our purpose. An integrated processor manages the image processing and sends the coordintate data of the four brightest spots via bluetooth to the tracking computer.
The players wear headbands, with three infrared light-emitting diodes fixed on top that are aquired by the infrared cameras above the players heads. A library written for the realtime programming language Pure Data transforms the 2D-coordinates into a 3D-vector pointing at the viewing direction of the respective player/trader.

Projection Environment TU Graz Institute for Computer Graphics and Vision (ICG)

The multi-projector display of the TIYF! installation is located in a 10x10x3 meters (WxHxD) space. Six projection canvases have been constructed. Each canvas is tilted by 10 to 20 degrees towards the room center and seamlessly connected to its neighboring canvases. The resulting projection surface has a perimeter of almost 20 meters and features a roughly circular shape around the room centre thereby spreading an angle of approx. 270 degrees. The entire surface is lit by eight overlapping projectors. For the detection of the projected geometry, eight cameras are required. Projectors and cameras are all connected with a single PC.

The Deskotheque display system supports the deployment of multi-projector displays on multi-planar surfaces suited for configurations such as described above. We have developed a projector-camera system which enables the usage of consumer hardware for the construction of continuous displays. The parallel usage of cameras allows for observing and detecting distorted projection images. These vision-based calculations finally result in a virtual three-dimensional model of the projection display environment.

The Market Model by Wolfgang Höchtl

The Trend Is Your Friend! examines the behaviours of different actors under artistic and game theoretical aspects. The game tests the players' reactions towards risk, appreciation in value, courage, and indifference. The participants trade with an asymmetrical standard endowment of money and shares. The market model is based on the "double auction" (as formulated by Nobel Laureate Vernon Smith in 1962). In a given time frame of 30 seconds, the traders can emit buy or sell orders. The system allocates the market price from the lowest ask price and the highest bid price. The traders are allowed to trade one share in each period. After clearing the transactions, the portfolios and accounts are updated. Subsequently, the status of the world is determined for the period, and the traders receive a dividend. A new trading period starts. Thus, prices and trade develop and a chart is traced based on the trades.