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The Lab collaborated in this project with students from different departmentsof the KABK: Ferenc Molnar, Mit Koevoets, Jing Foon Yu, MarcelKerkmans and Alrik Stelling. The AR Lab team consisted of: YolandeKolstee, Wim van Eck, Melissa Coleman en Pawel Pokutycki, supported byMartin Sjardijn and Joachim Rotteveel.Original photograph by Klaas A. MulderImage 12To be able to place the photograph of thesculpture in our 3d scene we have to assignit to a placeholder, a single polygon, image 7shows how this could look.This actually looks quite awful, we see thestatue but also all the white around it from theimage. To solve this we need to make usage ofsomething called an alpha channel, an optionyou can find in every 3d animation package(image 8 shows where it is located in the materialeditor of Cinema 4d). An alpha channel isa grayscale image which declares which partsof an image are visible, white is opaque, blackis transparent. Detailed tutorials about alphachannels are easily found on the internet.As you can see this looks much better (image 9).We followed the same procedure for the secondstatue and the grass (image 10), using manyseparate polygons to create enough randomnessfor the grass. As long as you see these modelsfrom the right angle they look quite realistic(image 11). In this case this 2.5d approach probablygives even better results than a ‘normal’ 3dmodel, and it is much easier to create. Anotheradvantage is that the 2.5d approach is very easyto compute since it uses few polygons, so youdon’t need a very powerful computer to run itor you can have many models on screen at thesame time. Image 12 shows the final setup.For the iglo sculpture by Mario Merz we useda similar approach. A graphic design studentimagined what could be living inside the iglo,and started drawing a variety of plants andcreatures. Using the same 2.5d approach asdescribed before we used these drawings andplaced them around the iglo, and an animationwas shown of a plant growing out of the iglo(image 12).We can conclude that it is good practice toanalyze your scene before you start making your3d models. You don’t always need to model allthe detail, and using photographs or drawingscan be a very good alternative. The next issueof AR[t] will feature a new ‘How did we do it’, incase you have any questions you can contact meat w.vaneck@kabk.nl40 41