The Mary Queen of Scots Channel Anamorphosis: A 3D Simulation | Hacker News Reader

The Mary Queen of Scots Channel Anamorphosis: A 3D Simulation

charlespetzold.com

80 pointswarrenm14 comments

I wondered how the original was made. Did they paint the whole thing at once and then pleat it? Or was it made of two paintings that were cut up?

It seems to be much simpler than that; the prisms were solid and removable. So you just put them in a rack so all of one side is flat, and paint directly on them. When that painting is done, you rotate all the prisms to the next side and do the second painting.

https://en.wikipedia.org/wiki/Tabula_scalata

> The artist is unknown but the date of composition is given as 1580, which is several years before Mary was executed, so the transformation into a skull seems a little premature.

Mary Queen of Scots was imprisoned by the English for about 19 years before her execution and was pretty unpopular in Scotland during that period. So it is entirely possible that her morphing into a skull was intentional.

It seems hard to believe it was not intentional!

Yes, wrong word. I meant it accurately reflected sentiment at the time.

Thought the name seemed familiar; he wrote a number of the early MS .NET 2000's era of C#, VB.Net and other Microsoft Press books. Warms the heart to see an industry mentor bang out goofy stuff for curiosity and fun.

He wrote Programming Windows 3.1 which was the classic reference for Windows programming in the 90s and just known as ‘Petzold’. All Win16 and C. The managed languages are much later.

For a moment I was really confused about this purported achievement of late Mary Stuart before my brain made the right connection.

Now that he’s got it in a computer, it might be interesting to ask questions like: what’s the geometry that has the sharpest transition, while also preserving some sort of “good view” of the two subjects from a lot of viewing angles. I think this is not even a good phrasing of the problem yet, but phrasing the problem well is part of the fun.

I guess this could be interestingly image-dependent. In particular she’s quite pale, so I wonder how many surfaces could be shared between the two images.

That'd be pretty easy to throw into an optimizer. For each configuration, you could calculate the "fitness" by just sampling the anamorphic rendering at various angles and do pixel by pixel comparisons to ground truth rendered single-image portraits of the two images rendered at the same angle. Could use nearly any metaheuristic super easy with that setup.

isn't likely that these art works were built to be viewed at a specific distance, perhaps while hand held, and that the full effect is experienced useing binocular vision while shifting ones view point, and that it is impossible to digitise that

Interesting and fun read, but I kept waiting for it to come back to logarithms. Seems there might be something there in the prisms?

The Brothers Quay did a fantastic (and predictably nightmarish) stop-motion exposition of anamorphosis: https://www.youtube.com/watch?v=cEfwbnMf3jM

Neat, it's like lenticular printing, but without the lens sheet

Neat!

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