Assignment #2: Bouncing Ball Obstacle Course

Assigned: Thursday, October 4th, 2012
Due: Thursday, October 11th @ 3:00 PM

Resources:

• Obstacle course and ball rig.
• Animation Exercises:
  1. Basic Animation Exercise
  2. Graph Editor Exercise
  3. Animation Principles

You will be animating a single bouncing ball with forward momentum from an orthographic side view in Maya, using the planning sheet you drew at the end of last week as a starting point. The ball falls into an obstacle course and eventually bounces/rolls to a halt. Before proceeding with the assignment, read through exercises 1 and 2 above. They will go over the basics of keyframe animation in Maya.

Setting Up

Open up the provided Maya file. You will see that the scene consists of both an obstacle course set and a ball rig. As with your planning sheet, the ball must begin its movement at the predefined starting position. Also note that all of the contstraints listed last week are still in effect.

It can be treated as if it is a ping pong ball, bowling ball, or anything inbetween. However, whatever physical properties you choose the ball must not be overly squishy nor can it be floaty like a partially deflated balloon. At a minimum the ball should fall into the lower level of the obstacle course and react appropriately to anything it touches. Draw the ball up to the point at which it comes to a rest.

Extra Credit: Remember that you can add an obstacle and animate your ball contacting it (wall, ramp, swinging arm, etc). If this was not included last week, you may still add it in.

Animation Workflow

There are two controls on the provided rig: the "ball_anim" is for both movement and rotation, while the "squash_anim" allows you to modify the direction and magnitude of the squash and stretch independent of the ball's position and rotation. This means that it is much easier to add/adjust squash and stretch without negatively impacting other portions of your animation. You should always key both controls on a given frame, and not just one without the other.

Use your planning sheet as reference for a first pass of poses. As you work in Maya and play back your animation you may find that adjustments will need to be made. Ultimately, you are not required to follow the exact path and timing of the planning sheet. If you find that deviating will result in a better final product, by all means do so!

Think about the animation principles, particularly squash and stretch, ease-in ease-out, timing, and arcs. For this assignment you shouldn't see squash and stretch on the ball when playing at full speed but you should be still be able to feel it. Squash and stretch that spans too many frames will make the ball look like it is willing itself to jump. In general just use one or two frames for squash.

General Animation and Maya Tips

• Start with your "extreme" poses first! Get those right, then add breakdowns (poses further defining the motion between your extremes) as you need them.
• When defining poses for your ball you will want to key both controls on the same frame. If you stagger their keys (meaning, for example, that the ball_anim's keys don't line up with the squash_anim's keys), figuring out which key goes to which pose will become frustrating later and slow down the workflow. Keying all controls on the same frame is an important habit to start now, as the number of controls per rig will only increase from here.
• Make sure keys don't land on partial frames (for example, frame 3.14). If this happens it is usually the result of key scaling. To fix partial framed keys, select all of the problem keys in the timeline, right-click hold on the selection, and choose "Snap".
• Try not to spend too much time in the Graph Editor. Focus on what your animation looks like, not what the curves look like. Don't be afraid to add more keys or breakdowns.
• Save iterations! You especially want to save an iteration when all of your key poses are set, before moving on to clean up the graph editor and adding in-betweens (basically another word for breakdowns).
• The default playblast resolution is 1280x720, but for temporary playblasts it may be faster to lower the resolution to 640x360. The easiest way to do this is to keep the Scale at "0.50" in the Playblast Settings. Just be sure to change it back to the original resolution before turn in.
  
  

Turn-in Checklist

• MOTION CHECK-IN:
  • First iteration of the bouncing ball, stepped poses are fine (already playblasted!) Also this is when you need to indicate the type of ball you are animating (ping pong, bowling, rubber, etc.)
    
    
• Use .ma and not .mb
• Please name your files lastname_firstname_assignmentnumber_filename.* (example:
  doe_john_a1_bouncing_ball.ma)
• Turn your files into production1/cse459_au12_turn_in/assignment_2
• One 1280x720 playblast of the render_cam orthographic side view.
• One Maya file for your bouncing ball.