1. An input apparatus for a computer device, comprising: a computer processor configured to execute computer executable instructions, wherein the instructions are configured to cause the computer device to: a) obtain an image of a least a portion of a structurally encoded pattern formed on a surface from a camera, wherein the structurally encoded pattern includes a plurality of elements, wherein each element is encoded with information identifying a location and orientation of the element with respect to the surface; and b) identify at least a portion of one or more pattern elements in the image; and c) determine a position of the camera relative to the surface from the information encoded in the one or more pattern elements in the image.