Alice: A Free 3D Animation
World for Teaching
Programming
Barbara Ericson [email protected]
Georgia Institute of Technology
Oct 2005
What is Alice?
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
Free 3d animation software
 From Carnegie Mellon University
 Available from http://www.alice.org
Used to teach
 Programming concepts
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Objects and classes
Methods, functions, and properties
Conditionals (if and else)
Iteration (looping)
Recursion
Event-driven programming
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Alice Requirements
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Modern Computer
 500 MHz CPU or better
 128 MB RAM or better
 Video resolution of 1024 by 768 or better
 VGA graphics card with 16 bit or better color
 A sound card
Does work on windows and macs
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Why Learn to Program?

Number of CS Majors is down 40%


Predicted to be one of the fastest growing fields
through 2012


US Dept of Labor
The number of jobs in computing is now greater
than in 2001


Since 2001
And growing
We are facing a massive shortage of people

With knowledge of computing
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Why don’t Students want to Program?

Myth: all the jobs are going overseas

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Myth: You have to be a nerd or geek

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Less than 1% have
Programming won’t turn you into a nerd or geek
Students perception of programming:
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Too hard
Not interesting
Not relevant
Not creative
Not social
Too math based
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Why Use Alice?
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Students find using Alice
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Easier than textual programming

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Motivating
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Students are used to 3d games and animated movies
Creative
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People love to tell stories
Relevant

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No syntax errors
Like being the director of a movie or play
Social

Share what was created
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Getting Started

Install Alice

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Start Alice


Copy folder from CD
Double Click on Icon
(Alice.exe)
Wait for Alice to start

Can take a few minutes
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Pick a World

Click on the Examples
tab

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And click on a world to
open it
You might need to scroll
down to see this world
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Playing the Movie

To play a saved movie

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Click the Play button
The movie or game will
start to play in a
separate window

Click on target to play
this movie

Most example worlds will
just start to play
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Create Your Own Movie

Click on File

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Then New World
Click on a template

Background and ground
type
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Add Objects To the World
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Click the Add Objects
button
Select an Object
Category from the
Local Gallery
Select Local Gallery
to get back from a
category

To the list of categories
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Add Objects to the World

Select an object to add

Click on object to select

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Click Add Instance to
world Button
Or drag the object and
drop it into position in the
world
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Position an Object in the World

Once the object is in
the world

You can move it by



Dragging it with the
mouse
Or using the mouse
controls
Click the Undo button
to undo the last action
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Mouse Controls

Use mouse control buttons (from left to right)
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To move object left, right, forward, back
Up and down
Turn left or right
Turn forward or backwards
Tumble the object (free rotation)
Resize object
Copy the object
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Deleting an Object

Click on the object you
want to delete
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
The object will be
displayed with a
bounding box around it
Click the right mouse
button

Select delete from the
pop-up menu
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Posing an Object

You can move just a
part of an object

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Select a part to move
with the mouse
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Click affect subparts box
under mouse controls
Mouse controls will affect
just that part
Or use the object tree

To pick the part to move
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Ask Objects to do Things in Methods
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In object-oriented
programming we ask
objects to do things
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They can refuse
They ‘know’ how to do
things
In Alice we will do this
in a method

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Please
clean your
room
Sure
A named set of requests
to objects
The play button executes

world.my first method
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Viewing Methods


Click the Done button
to stop adding objects
to your scene
Click the object that you
want to do something


In the object tree
Click on the Methods
tab

To see the methods this
object already knows
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Use Methods

Drag method names
from the details window
Methods area


to world.my first method
Can Group Methods

Do in order

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One after the other
Or Do together

At the same time
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Moving and Deleting a Method

You can pick up a
method and move it
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Click on left (dotted)
edge and drag it
Legal places to drop it
will have a green line
To delete move to the
trash can

Or right click and pick
delete from the popup
menu
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Posing an Object using the Menu

You can also use a
popup menu to pose an
object

Right click on an object in
the object tree to bring up
the methods


Select a method to
execute it
Click on the Undo button
to undo this action
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Quad View
Click here to see Quad View

Use the Quad View to
get multiple views of
your objects
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Normal camera view
From the top
From the right
From the front
Can zoom
And move the view
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Camera Controls
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Use camera controls to
change the starting
camera view
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Move up, down, left, right
Drive forwards,
backwards, rotate left,
rotate right
Tilt (rotate) camera
forwards or backwards
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Saving a World


Click on File and Save
World
Tell it where you want
to save it


Give it a name
To open a saved world

Click on File, Open World

Pick the saved world
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Creating a Method

To teach an object to
do a new thing

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Create a new method
Name the method
Drag other methods into
the new method
When you are done use
the new method in
world.my first method
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Creating a Class
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A class can ‘inherit’ from an existing class

Right click on object in object tree and rename it
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Create copies of the object using mouse controls
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Right click and select save object (really save class)
Know the same methods
To make the methods work on any object of the
class
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Add a parameter for the object that it is invoked on
To move sub-parts need part named function

Be careful typing the name of the part
 Case sensitive
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Creating People

You can use the she
builder and he builder
to build custom people

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In the people category
Control the skin color,
hair, eyes, body, and
clothes
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Saving a Position
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Click the more
controls button
Drop a dummy
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At the camera
Or at an object
Can move the
camera to a dummy
Can set an object to
the dummy’s
position
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What can you teach with Alice?

Basics of Object-Oriented Programming
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Objects and Classes
Methods and Parameters
Inheritance (the concept of it)
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Alice doesn’t fully support inheritance
Iteration (looping)
Conditionals
Recursion
Lists and list processing
Arrays
Algorithm design, implementation, and testing
Basics of Event-driven programming
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Alice Tutorials
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Click on File then Open
World
Click on the Tutorial tab
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And then click on a
tutorial to run
When you finish with one
tutorial do the next the
same way
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Resources
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Web site
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Book: Learning to Program with Alice
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Wanda Dann, Stephen Cooper, Randy Pausch
Short Workshops at Georgia Tech
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http://www.alice.org
Check web site for teacher workshops
http://coweb.cc.gatech.edu/ice-gt/
Summer 2-day workshops across the country
Curricular materials

http://aliceprogramming.net/
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