This page is explains the process and components needed to create a large open world environment on the PS3. The open cities are the size of Manhattan and to pull that off we needed to stream in data on a block my block basis. Each Block is designed to be 128 meters x 128 meters. I defined a system that included lower fidelity assets that stay in persistent memory along with higher fidelity assets that stream in as you move through he open city. If you fly up to the top of the world you can see across the whole city.

The Architecture details such as store fronts, signs, building light fixtures, roof top assets and planters are know as stick-ons. These are higher fidelity assets that stream in 1.5 block radius from you. Below I have the simple building shell highlighted so anything else you see on that block other than the ground tile being the street is streamed in close to you.

The Streaming system also takes into account the vertical distance you are from an asset. The Image below shows rooftop asset drawn in but the street level signs, parking meters, and traffic lights are not.

The Following information is a Document that explains in more detail how this system works and the math needed to to ensure that the streaming sys does not get overloaded. Having strict standards such as these made the development of 2 large cities with 20 environment artist much easier to manage.