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Course: Pixar in a Box > Unit 11
Lesson 1: Modeling grass with parabolas- Start here!
- Introduction to parabolic arcs
- 1. String art
- String art construction
- 2. Midpoint formula
- Midpoint formula
- 3. Parabolic arcs
- Parabolic curve matching
- 4. Modeling grass
- Design challenge: Modeling grass
- 5. Animating grass
- Design challenge: Animating grass
- Getting to know Tony DeRose
- Hands-on activity
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Start here!
Overview of modeling grass with parabolas
Welcome to environment modeling!
In this topic we're going to explore how realistic blades of grass are modeled using parabolic arcs.
This topic contains two lessons:
- Appropriate for grades five and up
- Design your own blade of grass using midpoints and simulate it as a flowing field.
- Appropriate for grades nine to 12
- Discover the equation used at Pixar to efficiently draw parabolic arcs.
Have fun!
Want to join the conversation?
what is/are parabolic arcs?(60 votes)
A parabolic arc is a section of a parabola. A parabola is a curve whose equation is in the form y = ax^2 + bx + c
You can learn more about parabolas here: https://www.khanacademy.org/math/algebra/quadratics(66 votes)
Is it possible to code a parabolic arc like the one shown above using one or two for loops and a line?(19 votes)- Yes, you can do with a single for loop. You can see a version here: https://www.khanacademy.org/pixar/parabolic-interpolation/5746702332723200
(Lines 110 - 116). You can change the RESOLUTION variable to make the line more or less smooth.(23 votes)
Is this how people to animation? Its cool!(11 votes)- Mathematics are used throughout the Pixar in a Box course, and computers have the capability to convert math equations into full-scale movies. ;)(13 votes)
This page says that lesson 2 is appropriate for the high school level. Why is that? Is there anything I need to learn especially for that lesson?(15 votes)
probably because there might be some math that you learn in 9th to 12th grade which you might need here(1 vote)
What grade would be considered high school level for lesson 2?(8 votes)
The first part of lesson 2 is appropriate for all ages, the second lesson is closer to a grade 9 level. Remember you can do these lessons in any order as well!(8 votes)
What point are you guys making here in this article and besides it only tells of the blades of grass using parabolic arcs?(3 votes)
Probably as in that scene the grass is waving in the wind, front and back, so they need to use parabolic arcs for the movement of the grass(2 votes)
This is soooo awsome. I am gonna work at walt disney animation studios in a few years after high school and college and was wondering how many years of computer studies do you have to have?(3 votes)
I think it depend on your knowledge and adoption of the knowledge.(3 votes)
- what are parabolic arcs(3 votes)
- I'm confused about this(3 votes)
Why are parabolas important?(3 votes)