ABSTRACT
This chapter looks at obstruction, occlusion, and propagation along with the high-level considerations of a system that implements these methods requires. It helps listener to represent the movable position in the world where the sound is being perceived from. It limits the definition of obstruction to deflection and separates the modeling of transmission through obstacles to occlusion. The primary advantage of using preexisting environment information reduces the amount of work that the sound designers are required to do. However, with the constraint of processing time allocated to audio, using complex geometry like lighting, or even collision meshes, does not prove to be the best choice. No matter how the geometry is provided for the audio systems to use, it is always important to remember that there are exceptions to the rule. The tools for the sound designers makes an exception based on artistic choice, a bug, or optimization is important.
