1. A computer-implemented method for producing an interactive virtual movie, which simulates the walking of a user within a real site and exploring the same, comprising: receiving minimal conditions for capturing photographs by a camera attached to a scanning apparatus, wherein the minimal conditions include one or more of: (a) a minimum change in the apparatus's displacement relative to the site floor by a distance D; (b) a minimum change of the apparatus's orientation about an axis essentially perpendicular to the site floor by an angle Δ°; or (c) a minimum change of the camera's orientation relative to the apparatus by an angle of δ°; capturing a plurality of photographs, wherein the plurality of photographs are captured through: sequential route photographing that includes moving the scanning apparatus along a route, determining a change in the values of D and Δ°, and capturing a photograph at least each time the change in D or the change Δ° exceed its respective minimal condition, wherein the measurements of the change of the values D and Δ° are reset after each photograph is captured; or sequential junction photographing that includes, while the apparatus is stationary, determining a change in the value δ° and capturing a photograph at least each time the change in the value δ° exceeds its respective minimal condition; forming open chains, wherein each open chain including those photographs captured during a sequential route photographing session, and wherein each open chain is defined by an end photograph at each of the start and finish of a route; forming closed chains, wherein each closed chain including those photographs captured during a sequential junction photographing; and for at least a portion of the open chains with a respective end photograph that is captured adjacent to a junction: determining, from among the closed chain photographs that correspond to the junction, a connecting photograph that meets a similarity threshold with the respective end photograph, wherein the similarity threshold is determined using a criteria of highest correlation or a closest field of view direction; and associating the respective end photograph with the connecting photograph.