1. A method of generating a lookup table for use in estimating spatial depth in a visual scene, comprising: at an electronic system having one or more processors, and memory storing one or more programs configured for execution by the one or more processors: identifying a plurality of subsets of illuminators of a camera system that has a plurality of image sensors and a plurality of illuminators, wherein the plurality of image sensors are associated with a plurality of pixels; for each pixel, and for each of a plurality of depths from the pixel: simulating a virtual surface at the depth; for each subset of the plurality of subsets of illuminators, simulating illumination of the virtual surface from the subset; determining an expected light intensity at the pixel from light reflected from the virtual surface due to the simulated illumination; forming intensity information from the expected light intensity determined for the pixel for each of the depths and each of the subsets; and constructing a lookup table comprising the intensity information, wherein the lookup table associates the intensity information for each pixel with the respective depths and the respective subsets.