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Pixar in a Box
Course: Pixar in a Box > Unit 4
Lesson 1: Hair simulation 101Case study: The Good Dinosaur
Find out how hair simulation tools were used in the film the Good Dinosaur.
Want to join the conversation?
- Is there only on kind of animators, are there different kinds? And if so, who are they and what are their jobs?(8 votes)
- There are many different kinds of animators including:
Texture Artists - These people make the images that are applied to the surface of 3D shapes (i.e. skin texture, dirt, clothing colors, and just about all color you see in a movie) and may define how a surface reacts with light (will it be shiny or defuse, emit light or absorb it, seem rough or smooth, etc.)
Modelers - These people create the 3D shapes used throughout the movies (cars, characters, landscapes, etc), these artists create the forms that the texture artists apply color to.
Simulation Artists - These people create things that move, not indivitualy by animators, but whose actions are calculated by computer programs, these things would include fire, smoke, water splashes (a lot of smooth water or simple waves can be calculated using less intense methods), sea spray, sand, and many MANY other things.
Animators - These people make the modeled and textured objects move. They could be doing anything from making character's arms move, to making the wheels and pistons on a steam train move realistically.
There are also many other "animation" jobs which may be considered subcatagories of ones I have already listed such as rigging, sculpting, lighting, and many more.(24 votes)
- Atwhy is Spot's family's hair all white, and his is brown? 3:08(6 votes)
- Oh, that happened in the movie.
I think it is because the moved on to a new age.
Notice they had fur clothes while he wore leaves.
It was just another way of differentiating.(14 votes)
- Who makes the colors for the pixar movies?(8 votes)
- For your question i'm assuming that you're talking about the setting, characters, etc. The idea for the movies come first, then they start sketching the design, and when they're happy then they plan the colours.(8 votes)
- What I want to know is who worked on the water in The Good Dinosaur?(6 votes)
- Why is my video not turning on.(5 votes)
- Do you think the next lesson would be fine for me as a 13-year-old?(3 votes)
- yeah im 14 and doing all the lessons(3 votes)
- they are preety good at this(3 votes)
- Did you watch that movie before ?(2 votes)
- For the background, we use different kinds of light to make colors. For the character, artist and sculptor can paint color and then use computer programming to make colors. (I think)(2 votes)
- Is the modeling software shown in the video for making the clumps of hair RenderMan?(1 vote)
Video transcript
- So far we've been exploring
what a software engineer does at Pixar, which is
creating the tools used in the filmmaking process,
such as a hair simulator and all the parameters
artists can't control. The person actually using
these tools in each film is known at Pixar as
the Technical Director. To better understand this kind of work, we've invited Jacob Brooks,
a technical director who has used hair simulation in our films. Hey Jacob. - Hey, how are you? - Pretty good, so you worked
on Spot for The Good Dinosaur, - I did, I did, yeah. - So were the artistic goals for Spot's hair? - Well Spot was one of those
characters that you knew we wanted to fall in love with right away. So he had a lot of appeal in him, but he also kind of
straddles that world of being in the wilderness so he's gotta
wild and a little unkempt. So with his hair we were
able to kind of bridge those two worlds so that you
can still get that feeling of kind of a matted tangled,
kind of wild animal feel to him but also get that appeal of like, just a child that wakes up in the morning and has adorable bed head. So it's just super familiar to us. So for the hair, as far
as the texture goes, we knew we were gonna have to have strands that were intertwining
and felt like they hadn't been washed in a while, not
going towards that gross factor but something that definitely feels entangled and unkempt,
but also just kind of hit those shapes that we knew
that we'd want to just frame his face nicely and be appealing, so that he does have that
genuine appeal in the film. - So how did you model the
hair to meet these artistic goals? - Well before we can
actually simulate the hair on a character that's moving,
like Spot as he's running around in the film, we actually
have to groom the hair, we have to model that shape, and for Spot, it was an interesting
challenge because his hair is so tangled it becomes
a very important thing to make sure those hairs aren't
intersecting in weird ways and that you can feel that
the hairs are actually twisting around one another,
in order to do that, we ended up using a
technique that was developed at Disney Animation where
we're using geometric tubes to shape gross shapes in his hair, so that you can really get the appeal of individual clumps of hair,
and see how it tapers along towards the end of the
hair, so with those tubes, once they're shaped in a certain way, we fill those tubes with
curves, and those are the curves that we end up simulating
as we go forward. - Now that you had the
shape that you wanted, how did you set up the
hair simulation to get the look that you wanted? - The sim of the hair for him is obviously a little bit different as
well because you've got this mangled mass of hair, it
needs to hold that shape, and it doesn't move like
even your hair would or someone with straighter
hair, so it doesn't hang with gravity like you would
think, as a whole for Spot, his hair is a little tighter
than most of our hair, the springs are a little bit
tighter so that you don't get quite as much sag
and it really does feel like it's been teased and
frazzled and kind of holds up and defies gravity a little
bit more than natural like longer hair would be. - [Interviewer] So Spot
had variation for his hair. Like when he was wet, so how
were you able to do that? - Because he was in the
wilderness and we knew there was a bunch of weather
changes where sometimes it's starting to rain,
sometimes it's in the middle of the rain where it's getting heavier, and sometimes he's soaking wet
'cause he gets in the river, my colleague David Liley and
I worked on something to where we started thinking
hey, wouldn't it be cool if we just changed simulation
parameters to get the hair that he started with to
be the hair as it changes. And so he started on the
soaked version of the groom, and by changing things like
the stiffness of the springs we could lose that groomed
shape that was all spirally, it would make it kind of flattened out, we would turn up the
gravity so that it hanged a little bit tighter to his face. So what that allowed us to
do was change the simulation parameters a little bit at a time, so maybe gravity would
get a little bit stronger or the springs would
get a little bit looser, so that you can get a
variation of that transition from dry to wet, but you had
various stages in the middle that you could get which
normally if we were just doing independent grooms, we
would have more of this kind of on and off switch, of
like, it's dry, it's wet, now we can get a nice
blend through that range. - That's pretty cool,
thanks Jacob for coming by. And now onto lesson two.