|This image was created for a flyer .|
|The viewer initially see the image of the closed strongbox .|
|When he opens a leaf of paper that simulates the door|
|then it's shown the inner of the strongbox empty.|
|The job required to create the inner of the strongbox as well as the "door"|
|using the existing texture of the closed door from the original picture.|
|In order to predict the exact direction of the shadow casted|
inside the box a 3D image was rendered as reference.