In one embodiment, a method includes accessing a first distortion definition for a first color component and a second distortion definition for a second color component; generating, for a pixel, a first ray for the first color component of the pixel and a second ray for the second component of the pixel; defining trajectories for the first and second rays using the first and second distortion definitions, respectively; casting, from a viewpoint in a 3D space, the first and second rays into the 3D space using the defined trajectories; computing, for the first and second rays, a first intersection location and a second intersection location with one or more objects in the 3D space; and determining a color value for the pixel based on the first and second intersection locations.