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=Image 7Image 5A webcam was placed on top of the screen,and a laptop running ARToolkit (http://www.hitl.washington.edu/artoolkit) was mountedon the back of the screen. A large marker wasplaced near the sculpture as a reference pointfor ARToolkit.Now it was time to create the 3d models of theextra couple and environment. The studentsworking on this part of the project didn’t havemuch experience with 3d animation, and therewasn’t much time to teach them, so manuallymodeling the sculptures would be a difficult task.Soon options such as 3d scanning the sculpturewere opted, but it still needs quite some skillto actually prepare a 3d scan for AugmentedReality usage. We will talk more about that ina coming issue of this magazine.But when we look carefully at our setup (image5) we can draw some interesting conclusions.Our screen is immobile, we will always see ouradded 3d model from the same angle. So sincewe will never be able to see the back of the 3dmodel there is no need to actually model thispart. This is a common practice while making 3dmodels, you can compare it with set constructionfor Hollywood movies where they also onlyactually build what the camera will see. This willalready save us quite some work. We can alsosee the screen is positioned quite far away fromthe sculpture, and when an object is viewedfrom a distance it will optically lose its depth.When you are one meter away from an objectand take one step aside you will see the side ofthe object, but if the same object is a hundredmeter away you will hardly see a change in perspectivewhen changing your position (see image6). From that distance people will hardly see thedifference between an actual 3d model and aplain 2d image. This means we could actually usephotographs or drawings instead of a complex 3dmodel, making the whole process easier again.We decided to follow this route.Image 6Image 8Image 9Image 10Image 113839