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Support springs

Now we'll explore a method to develop curly looking hair.

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  • hopper jumping style avatar for user Snylon
    Is it like bézier curves while before it was linear interpolation?
    (5 votes)
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  • leafers ultimate style avatar for user kerin
    How did the team built up the function of parameters? How did they calculate the net force?
    (5 votes)
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  • winston default style avatar for user ethan.wang
    how does support springs even work?
    (2 votes)
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    • hopper happy style avatar for user noam freeman
      The support spings make the points they connect on the hair "want to stay close".

      :et's think about only one support string:
      Without it, the only force on the hair is the gravity , so "it wants" to fall straight down.
      With one support spring, there is a force pulling the two connected point together. So te hair wont fall straight down, but would make some arc between the 2 points.

      Now, with many support springs, we have many arcs.

      I beliave they used another layer of support strings connecting the first one (or even more), so all the arc continue one another in a smooth way.
      (5 votes)
  • blobby green style avatar for user merrek.klein
    I don't understand this very well but what if you were able to add a compound that would keep the hair curly without needing spring support
    (2 votes)
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  • orange juice squid orange style avatar for user [ | ŪnørthdöxBôx | ]
    Did you know that pausing the video gives you points easily? I didn’t
    (2 votes)
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  • blobby green style avatar for user robert.lloyd
    why is the video stuck at half waY??
    (2 votes)
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  • winston default style avatar for user NANI
    great work so far we build up a model of hair using a series of damped Springs this gives us a more realistic behavior like this style I came up with but remember the art department once Merida's hair to be curly sometimes it curls up while moving but it doesn't hold that curly shape while at rest here's an idea what if we put some smaller Springs in between the larger Springs to pull them together let's call them support Springs we already have a mathematical model of the spring so this is easy to test out if I connect a support spring between the larger Springs I'd get something like this if I hide the support Springs you'll notice the hair comes to rest in a curly shape that's much better adding these support Springs results in new parameters we can control the stiffness and length of the support Springs shorter support Springs will give us smaller curls while really long support Springs give us bigger ones and if we make the support Springs have a higher stiffness the curl pops up like this kind of like we applied hairspray compare this to support Springs with lower stiffness in this case the curls relax a bit and fall downwards in a natural way now let's try this with a bunch of hairs now that's starting to look more like Merida this isn't exactly the method we use on Merida for the movie but it's close in this next interactive you can try this out with all the parameters we've introduced the two new parameters are support spring stiffness and support spring length see what you can come up with
    (2 votes)
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    • spunky sam orange style avatar for user Elder Fauth
      great work so far we build up a model of hair using a series of damped Springs this gives us a more realistic behavior like this style I came up with but remember the art department once Merida's hair to be curly sometimes it curls up while moving but it doesn't hold that curly shape while at rest here's an idea what if we put some smaller Springs in between the larger Springs to pull them together let's call them support Springs we already have a mathematical model of the spring so this is easy to test out if I connect a support spring between the larger Springs I'd get something like this if I hide the support Springs you'll notice the hair comes to rest in a curly shape that's much better adding these support Springs results in new parameters we can control the stiffness and length of the support Springs shorter support Springs will give us smaller curls while really long support Springs give us bigger ones and if we make the support Springs have a higher stiffness the curl pops up like this kind of like we applied hairspray compare this to support Springs with lower stiffness in this case the curls relax a bit and fall downwards in a natural way now let's try this with a bunch of hairs now that's starting to look more like Merida this isn't exactly the method we use on Merida for the movie but it's close in this next interactive you can try this out with all the parameters we've introduced the two new parameters are support spring stiffness and support spring length see what you can come up with
      (1 vote)
  • duskpin tree style avatar for user rehbemad000
    so how do you create the hair?
    (1 vote)
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  • blobby green style avatar for user sizemoree
    wowzers! These effects are pretty epic! [Cool Face Emoji]
    (1 vote)
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  • leaf green style avatar for user crazy train
    so what was the method that was actually used in the movie :D ;
    (1 vote)
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Video transcript

(jumping, bouncing) (light switches on) - Great work. So far we've built up a model of hair using a series of damped springs. This gives us a more realistic behavior, like this style I came up with. But remember, the art department wants Merida's hair to be curly. Sometimes it curls up while moving but it doesn't hold that curly shape while at rest. Here's an idea. What if we put some smaller springs in between the larger springs to pull them together? Let's call them support springs. We already have a mathematical model of the spring so this is easy to test out. If I connect a support spring between the larger springs, I get something like this. If I hide the support springs, you'll notice the hair comes to a rest in a curly shape. That's much better. Adding these support springs results in new parameters we can control. The stiffness and length of the support springs. Shorter support springs will give us smaller curls, while really long support springs give us bigger ones. And if we make the support springs have a higher stiffness the curl pops up like this. Kind of like we applied hairspray. Compare this to support springs with lower stiffness. In this case, the curls relax a bit and fall downwards in a natural way. Now, let's try this with a bunch of hairs. Now that's starting to look more like Merida. This isn't exactly the method we used on Merida for the movie, but it's close. In this next interactive you can try this out with all the parameters we've introduced. The two new parameters are support spring stiffness and support spring length. See what you can come up with.