Terrain level of detail in first person-ground perspective simulations

Abstract

The Army Game Project at the Naval Postgraduate School is utilizing Epic's Unreal game engine to create a realistic first person infantry simulation. The project involves both indoor and outdoor spaces, including terrain datasets larger than normally supported by the Epic engine. While there has been extensive research relating to terrain rendering algorithms, they are unsuitable for this system due to hardware requirements, task limitation, or inefficient memory management. These limitations can be addressed by modifying the original terrain algorithm to include multiple levels of detail for complex terrain. This method raises new issues with projected textures, transparent textures, and multi-resolution rendering; therefore the implementation technique includes resolution for these concerns as well. The Epic world editor was also modified to enable world designers to control of these levels of detail. Performance tests have shown that this terrain level of detail system significantly improves display times, thereby allowing greater terrain complexity while maintaining interactive frame rates. Rendering times in environments with small terrains improved almost 40%, while large complex terrain environments (km2 at 1m resolution) fared even better.