1. A method for augmenting reality, comprising: computing, by one or more computing devices, a real-world depth map using real-world imagery captured by an imaging device; rendering, by the one or more computing devices, a computed depth map based on geographical data retrieved from a server; blending, by the one or more computing devices, the real-world depth map with the computed depth map to generate a composite depth map by: placing, by the one or more computing devices, depth data from the real-world depth map in the composite depth map for locations within a threshold distance between the imaging device and a feature in the real-world imagery captured by the imaging device, and placing, by the one or more computing devices, depth data from the computed depth map in the composite depth map for locations beyond the threshold distance.