Fall 2008 ACS-1805 Ron McFadyen 1

ACS-1805

Introduction to Programming

using Alice 2.0

Ron McFadyenCourse Outline

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Alice 2.0, an introduction

• Alice 2.0 is a modern programming environment with:

• 3-D graphics

• 3-D models of objects

• Text: Learning to program with Alice; contains CD with software

• Latest version available at www.alice.org

• Originated, and development continues, at Carnegie Mellon University

• A similar environment, Panda3d, exists for the more advanced programmer. Pand3d was originally developed at Disney.

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Alice 3.0

• CMU and Electronic Arts are developing Alice 3.0 to provide objects from "The Sims" in a complete Java environment.

• 2008 (?)

2.0 vs 3.0

An aside (a point of interest)

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Alice 2.0• Virtual worlds

• Start a program by playing a virtual world

• Can play like a movie, or play like an interactive game

• Developing a world begins with a template (e.g. ground & sky)

• Objects

• Objects are added to the world (e.g. a person, a robot, a ball)

• Objects are chosen from a gallery of 3D models

• Object-oriented

• objects can do things – we send them messages commanding them to do what is necessary for an animation (e.g. move, turn, speak)

• Commands are contained in methods

• Event-driven

• User can interact with a world using the mouse or keyboard

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Alice 2.0

• Emphasizes programming fundamentals

• Programs are composed of methods

• Methods contain Alice instructions

• Objects are asked to do things they know how to do

• Events can trigger execution of program components

• Programs always run

• Alice has a smart editor with visual drag & drop (you tend to use the mouse more than the keyboard)

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Demo1: running an example

• Start Alice

• Load and run a world

• snowLove (from Examples worlds)

• Pause, Restart, Stop

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Demo2: create a world

• Create a new world

• File New

• Select the Templates tab

• Choose a template

• Later on… remember to save your world

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Demo2: Adding objects• Adding

objects• Click the

Add Objects button

• Click on Home, Local Gallery, Animals

• Click and drag an animal to the world

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Demo2: Adding objects• Manipulating

a scene• Use your

mouse to move objects about

• Move the camera to get a different angle

• Switch to quad view to more precisely move objects about

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Classes• Objects are categorized/organized into classes

• e.g. Frog

• An object is an instance of the class.

• e.g frog1, george, mary

Frog

frog1marygeorge

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Object Parts• Objects may be complex

• aliceLiddell has a rightArm

• The rightArm comprises a shoulder, and forearm, and the forearm has subparts too.

• A “+” means there are subparts that can be listed by clicking on the “+”

• A “-” means the subparts are listed. To suppress the listing of subparts click the “-”

• The picture on the right is showing the objects in a “tree” view

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Object Parts

aliceLiddell

rightArm leftArm neck lowerBody

shoulder forearm

hand

thumb

fingerTips

fingers

forearm

hand

thumb

fingerTips

fingers

shoulder

Consider the aliceLiddell object to the right. A computer scientist typically uses tree diagrams for complex hierarchical structures. Can you complete this for neck and lowerBody?

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