Towards logic programming based coordination in virtual worlds

  • Paul Tarau
  • Veronica Dahl
  • Koen De Bosschere
Agent-Based Coordination
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1364)


We propose a unified framework for coordination in multiuser Virtual Worlds, based on our experience with LogiMOO, a BinProlog+Linda based programmable shared Virtual World. LogiMOO adopts unification for pattern retrieval while using exclusively deterministic operations, unlike most Prolog based Linda systems. Moving beyond the Linda framework LogiMOO is based on, we describe a coordination logic for agent programming based on ideas from (affine) linear logic and Java's synchronized object system as well as a set of new primitives describing uniformly Linda operation, database updates and hypothetical assumptions.

The main novelty is that our constructs emphasize an ‘object based’ approach, with synchronization information built in ‘container objects’ and allowing more flexible wait/notify negotiations between consumer/producer agent components, as well as inheritance and agent component reuse.

Our experiments with agent coding in LogiMOO and Java and interaction with external visual and logic components, show the practicality of our constructs for real life programming.


coordination languages blackboard-based logic programming distributed programming groupware virtual worlds Internet applications 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Paul Tarau
    • 1
  • Veronica Dahl
    • 2
  • Koen De Bosschere
    • 3
  1. 1.Département d'InformatiqueUniversité de MonctonMonctonCanada
  2. 2.Logic and Functional Programming Group Department of Computing SciencesSimon Fraser UniversityBurnabyCanada
  3. 3.Vakgroep Elektronica en InformatiesystemenUniversiteit GentGentBelgium

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