Abstract: Ambient occlusion is used widely for improving the realism of real-time lighting simulations. We present a new method for precomputed ambient occlusion where we store and retrieve unprocessed ambient-occlusion values in a three-dimensional grid. Our method is very easy to implement, has a reasonable memory cost, and has a rendering time independent of the complexity of the occluder or the receiving scene. This makes the algorithm highly suitable for games and other real-time applications.