software principles
The principle by which the viewers' motion is detected is based on statistic
information processing of the Passive InfraRed detectors (PIRs) situated
under the central object of the installation, the Moebius strip.
The System always considers the information received from three neighbouring
sensors. The sensors are not fixed in groups of three, but through reacting
to changes try to capture the impression of the sum of all movement in the
space (as opposed to considering specific trajectories of members of the
audience). This principle was chosen precisely because it does not give a
mechanical set of facts, (based on the laws of causality) for that which is
always possible but creates an impression that is true only once, analogous
to organic impression and reaction. The possibility of wilfully influencing
the installation is therefore excluded.
The System processes the gathered information and creates a dialectic
tension between the predetermined audio-visual flow and the processed
statistic information. The synthesis of the two makes a unique audio-visual
response which is directed personally to each individual spectator.
The software, running on the central computer, checks the state of the PIR
detectors, and then calculates the distribution of segments of images
representing the headlines between the six computers. Because of the
complexity of the projection surface and its aspect ratio, the whole image
is divided into six sections. Every section has its own dedicated computer
that generates the appropriate image segment. All the information is carried
through the network to the other computers. The same information is used to
control sound generation and distribution, also in six computers, each
generating two layers (a 12 speaker sound-system) of the total soundscape.
The sound moves within the 12 speaker sound-system and the thereby created
audio-panorama is genuine and not simulated. The sound materials themselves
are created by overloading electronic instruments - ie. trapping them
within feedback loops and imposing sound patterns based on their hardware
characteristics.
The installation software is written in JAVA programming language (Java2
platform, Standard Edition), with additional packages Java3D and JavaMedia
Framework. The application will run on PCs with Windows9x operating system.
Some of the routines for the acquisition of the state of PIR detectors are
written in another programming language (C), and linked with the main
application through the Java Native Interface.