Project 4 : Basic Motion

Date Assigned: Wednesday, February 11
Tutorials Due: Wednesday, February 18
Project Due: Wednesday, February 25

Reading: Kerlow, Chapters 9 and 10, Section 11.1
Learning Alias Lessons 15 and 16: (Learn about the Action Window.)


This assignment is about timing, weight, and squash-and-stretch. Your task is to animate a bouncing ball three times, emphasizing the difference in weight between each of three types of ball. You will work in a new group, giving each other feedback as you go. By the date this project is due, everyone in your group should be comfortable with Alias' keyframe animation interface and the basic principles of cartoon physics.


What to do

1. bouncing ball
Create a sphere with the default shading and lighting. Create three similar short animations (less than 4 seconds each) that show the difference between the following types of balls bouncing:
  1. A normal rubber ball.
  2. A beach ball.
  3. A bowling ball.
(Each group member should animate one of the above.)

2. expressive motion (optional)
Turn one of the balls above into a character with intent. Have the ball change its mind about what it's doing. Convey that mental decision using only the ball's motion.


What we're looking for

  1. This is a warm-up to get you thinking about weight, timing, and squash-and-stretch. Each animation should unmistakeably convey the type of ball using only its motion. Each of you should choose one ball to animate. Compare notes with your teammates as you go: discuss the different kinds of motion, and try to figure out the single most important aspect that distinguishes one ball from another.

    You will be turning in a flipbook of the bouncing ball with both shading and wireframe turned on. However, do NOT create any textures or render your scene as anything other than a playblast! The resolution should be low: around 360x240 pixels. The animation should play back at a rate of 24 FPS: be sure to set the frame rate every time you start Alias!

  2. For this part, try to think of a reason for the ball's action. If it suddenly decides to bounce in another direction, is it because it sees something it likes, or something it's afraid of? Also, think about how the ball feels about what it's doing. Is it excited, bored, exhausted? You may use a simple set for this part if it helps tell the story, but again you may NOT use extra lights or textures.

Turn in

Before class on Wednesday, February 25, make a group directory in /home/cse458/critique/basic_motion and put the following in it:

  1. README file.
  2. Animations of bouncing balls: rubber_ball.bk, beach_ball.bk, bowling_ball.bk.
  3. Animation of the expressive bouncing ball: living_ball.bk (optional).