In this article Daniel Harabor explains path symmetry: a property of uniform-cost grid maps and other regular search domains which can significantly slow down pathfinding. He describes how symmetry manifests itself and discusses approaches that have been tried to improve performance. Finally, two recent ideas from his doctoral research are outlined: Rectangular Symmetry Reduction (RSR) and Jump Point Search (JPS). Both are optimality-preserving techniques that explicitly identify and eliminate symmetry in order to speed up pathfinding by an order of magnitude and more. Their strengths, weaknesses are discussed as well as observed performance on two popular video-game benchmarks.

Every year AiGameDev.com runs its Awards for Game AI, shining the spotlight on the best releases of the past year. There are six different awards, ranging from technology to design and of course overall game of the year. For each, we've included the community vote results as well as the editor's choice.

In two weeks, we'll be releasing some exciting demos that have been in the pipeline and we thought it'd be a great opportunity to share some of the techniques we learned during development. This video tutorial in particular looks into some of the visualizations we built for one of our demos, called RUSHING BASES — including the area map, the hierarchical graph, the navigation view and the influence map.

Storytelling and games have a strange relationship. On the one hand, interminable cut-scenes can distract from gameplay and rigid storylines can constrain it. On the other hand, without some kind of narrative context, most games would be abstract and meaningless, and in the best of games characters and storylines add an immense amount to the experience.

The Paris Game/AI Conference 2011 that took place last month represented a turning point for the field of artificial intelligence in game development. While Game AI has traditionally been associated with non-player character behavior and occasionally opponent strategy, this was the first conference to showcase the newly found breadth of the field — from procedural generation to experience management, including data-mining and physics-based motion.

One month ago, I released a software product called "SimplePath" on the Unity Asset Store. SimplePath is a pathfinding middleware for the Unity game engine, which I recently started using after leaving my full-time job as an AI Programmer at Nihilistic Software, a company focused on the console gaming market. I had never released a piece of software on my own, and I noticed the Unity community's desire for a pathfinding software, so I felt like this was a good opportunity to see what it's like to self-release a small scale product.

In slightly over a week, the game development and artificial intelligence community will descend upon Paris for this year's annual Game/AI Conference 2011! Whether or not you can make it, here's a list of related research from around the web, our very own blog, and the PREMIUM area, to help you prepare for the onslaught of content. :-)