LICHTMAN: And, you know, I mean, that's the one thing that Kelly mentioned, that it takes a long time to render this kind of stuff, right? Can you give us a sense of how long it takes to actually output a shake of the head?ĭEROSE: Well, the outputting isn't so time-consuming, but doing the light simulation of how light interacts with all the hair and how the hair shadows each other, that's extremely computationally intensive.įLATOW: Give us a how long. But if you can capture the essential motion of about 100 hairs or so or 200, then you can kind of do in-betweening for the hair and get the basic motion at dramatically lower simulation cost. There are many more on an otter.įLATOW: Is that why we don't see many otter movies?ĭEROSE: That's why we don't see many otter movies - yeah. TONY DEROSE: As you said, there are about 100,000 hairs on a human head. But, you know - is the problem that they bump into each other and the static? I mean, how do you think about this problem of hair movement?ĭR.

I think Tony DeRose could probably talk about this better than I could. In this movie, they look at - they sort of boil it down to over 100, but even that is a really complicated question. So we have over 100,000 strands of hair on our real heads.

LICHTMAN: It's a - yeah, it's a really complicated question, it turns out. And then she found out that Disney was making this movie about Rapunzel, and it was like the dream fairytale ending for a student of hair modeling.įLATOW: So it was the film 'Tangled' and she - and in your video pick, she talks to you about how she had to mathematically model the hair and different. And I didn't even know this was a field you could study, but it just sort of gets to what we were talking about - become really good at something. And we talked with Kelly Ward, who's a senior software designer for Disney, and she had studied hair modeling in school. It's about the physics of Rapunzel's hair, is the topic of this week's video pick. I'm just going to fill it with bad jokes.

We have our Video Pick of the Week today, sort of an oldie goldie, right? Joining us now is our multimedia editor Flora Lichtman who is - welcome to SCIENCE FRIDAY, of course.įLATOW: We'll have a backend.

Barbie as rapunzel transcript