A display system produces three-dimensional images. The display system includes a waveguide, and a light source that injects light into the waveguide. A switchable grating allows individual positions in the grating in a two-dimensional array to be turned on and off. A controller configured to spatially modulate the switchable grating so as to control where light exits the waveguide. An eye tracking module tracks eye position of a viewer. The controller uses the eye position to control switching of the grating.