progression of CT scan of skull to a symetrical lo-poly model to be flattened in Blender

“Projection Mapped” Mirror Skull

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I was asked one evening by the Endless Reach guys if I would like to VJ at a halloween party, something subtle and psychedelic. Frankly the idea of spending 8 hours behind a laptop while everyone else has fun wasn’t too appealing.

As a compromise I suggested building a distorted mirror to play a long loop or even horror film at. The result would hopefully be exaggerated distortions thrown around the room.

A little more back and forth chat and I had persuaded myself to build faceted mirrorball skull, 2 meters high, for £50.  WOOPS!

 After a little mental RnD, I found a nice CT scan of a real human skull and set to work stripping it down and reducing the millions of polygons to a manageable quantity. This was then cut in half as a way to both make a symmetrical object and also save costs on pattern printing as all I would have to do is turn the sheet over. From here I needed to flatten the 3d into 2d polygons. Thanks to the guys at Inition and Devin who was sitting next to me at the time, we did a great three way research effort and found a plugin for Blender that would do the job for me. So I cracked open another bit of software and spat out the most horrifying array of triangles. Back to reducing the polygons again, and again and finally something that wasnt too scary.
paperfold skull
The Blender plugin had reduced my model to the minimum of islands and had annotated tabs for re-assembly, bloody marvellous. Unfortunately is was a terribly inefficient use of paper space for my pattern so I divided and reorganised the islands and annotated each polygon, just in case.
Flattened (A1 width) pattern for one half of the skull

Flattened (A1 width) pattern for one half of the skull

From here it was just a case of cutting the pattern (with a little help from Mike Kee), laminating some mylar mirror film to mount board, cutting the pattern out of that and then crying in the corner of the room, surrounded by triangular mirrors.

After regaining my composure it was just a task for some gaffa tape and some ingenious rigging to get the job done and assembled in the party space.

Pattern Cutting

This project had a certain production value from the outset so my “projection mapping” was going to reflect this. A quick photo on my phone of how the projection looked from the viewpoint of the projector lens and straight back to the computer to cut out all the background and white tape.

Photograph from the projector lens as a base to start constructing the matte.

Photograph from the projector lens as a base to start constructing the matte.

Would have loved to have spent longer mapping the beast and to have had a much brighter projector so I could have mapped the lux to each polygon, but for £70 spend, I was ecstatic with the results and even got a remote controlled smoke machine in its mouth. What’s not to love?

Skull is up. Mapping is a bit off due to long throw projector. Looks mental.

Click the pick to see a (very) short video.

Now as if this post wasn’t long enough, I had enough scrap mylar to make myself an outfit.

How do I look?

If you would like to make one yourself, just download the second picture on this post, scale it to A4 and cut it out. This will give you the pattern to make one half of the mask, its up to you what material you use, just make sure it has a bit of stiffness (anything over 300gsm should be fine.)

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