1. Introduction to Alice Alice is named in honor of Lewis Carroll’s Alice in Wonderland

2. Alice A modern programming tool 3-D graphics 3-D models of objects Animation Objects can be made to move around the virtual world (a video game or simulation implemented in 3-D) Two kinds of animations: Movie: passive user watches the animation Interactive: active user clicks on mouse, types a key on keyboard … Actions of user are called events

3. Demo: Getting started Starting Alice Load and run a world FairyCourt(movie) HelicopterSimulation(interactive) First program: Alice and WhiteRabbit welcome us to their world (movie)

4. 4 Getting and Running Alice Alice software is freely distributed Downloading Alice Go to the website: http://www.alice.org http://www.alice.org Click the link Get Alice 2.2 Click download link specific to your operating system Save Alice.zip (or Alice.dmg ) to your PC Installing and running Alice Extract Alice from Alice.zip (or Alice.dmg ) file Create desktop shortcut (alias) to Alice.exe Double-click Alice icon to launch Alice application

5. 5 The Alice Tutorials (continued) Go through the tutorials to learn the basics of Alice

6. Alice in Action with Java6 Program Design We don’t start with writing program code, very much the same as filmmaker don’t start with filming, rocket scientists don’t start with building rockets We start with design! Design is very important and affects the correctness and efficiency of the solution Design needs to revised, improved…

7. Alice in Action with Java7 User Stories Contain Basic description of what happens when program runs Nouns in sotry (Alice, the White Rabbit) correspond to objects Verbs correspond to actions, responses to messages Chronological flow describes the sequence of the actions When the program begins, Alice and the White Rabbit are facing each other, Alice on the left and the White Rabbit on the right. Alice turns her head and then greets us. The White Rabbit also turns and then greets us. Alice and the White Rabbit introduce themselves. Simultaneously, Alice and the White Rabbit say “Welcome to our world.”

8. Alice in Action with Java8 The Flow of User Story A numbered sequence of objects and actions 1. Alice turns her head toward the user 2. Alice greets the user 3. The white rabbit turns toward the user 4. The white rabbit greets the user 5. Alice introduces herself 6. The white rabbit introduces himself 7. Simultaneously, Alice and the white rabbit say “Welcome to our world.”

9. Alice in Action with Java9 Algorithms An algorithm is a sequence of step to solve a problem or perform a task Example algorithms: The flow of a user story Driving directions Cooking instructions Installation instructions Algorithms for search of records in phonebook, database, web… Algorithms for displaying, editing, animating pictures… Algorithms are generally not tied to programming languages Their implementations do

10. Alice in Action with Java10 Program Design For a given user story plan scents and shots Scene: a piece of the story usually set in one location Shot: part of scene told with camera in one position Create storyboards

11. Alice in Action with Java11 Transition Diagrams Link the multiple storyboard-sketches In a movie, transition diagram is a linear sequence In the first Alice program, there will be 7 actions

12. Alice in Action with Java12 Programming Implementation in Alice Templates provide a basic world environment Sample program is based on the “grass” Template Areas in the Alice window Menus: includes File, Edit, Tools, and Help Buttons: includes Play, Undo, and Redo Object tree: lists all world objects; e.g., ground Details area: includes properties, methods, functions World window: displays graphic objects in a program Editing area: includes editing space and controls Events area: contains actions responding to events

13. Alice in Action with Java13 Programming Implementation in Alice (continued)

14. Alice in Action with Java14 Program Style Change program display styles in Preferences How to access Preferences dialog box Click the Edit menu Click the Preferences choice Selecting a display style in Preferences dialog Click next to “display my program” in General tab Select a style Style recommended for course: Java Style in Color

15. Alice in Action with Java15 Program Style (continued)

16. Alice in Action with Java16 Adding Objects to Alice Class: blueprint for an object How to populate Alice world with objects Click Add Objects button in world window Locate class specifying the object in the Alice Gallery Right-click class and select “Add instance to world” Objects in sample world: aliceLiddell and whiteRabbit Naming conventions for objects and classes Class: capitalize all words; e.g., AliceLiddell Object: capitalize all but first word; e.g., aliceLiddell Objects can be renamed from the object tree

17. Alice in Action with Java17 Adding Objects to Alice (continued)

18. Alice in Action with Java18 Accessing Object Subparts Bounding box: encloses any Alice object Impact of selecting an object in the object tree Bounding box is drawn around object in world window Details area adapts to the selected object First action to program: Alice turns head to user First set of programming steps Select + sign next to aliceLiddell in object tree Select + sign next to neck subpart Select head (bounding box is drawn, details change) Drag doInOrder control to top of editing window

19. Alice in Action with Java19 Accessing Object Subparts (continued)

20. Alice in Action with Java20 Accessing Object Subparts (continued)

21. Alice in Action with Java21 Sending Messages Alice programs rely on sending messages to objects Objects’ methods deliver actions in response to messages Programming Alice’s head to turn Select Alice Liddell’s head in the object tree Scan through the methods in the details area Click on pointAt() Drag pointAt() to the editing area and drop it Specify camera as the target

22. Alice in Action with Java22 Sending Messages (continued)

23. Alice in Action with Java23 Testing and Debugging Bug: error interfering with normal program functions Debugging: process of removing program bugs Click the Play button to test Alice Liddell application Alice Liddell’s head will turn toward the user

24. Alice in Action with Java24 Testing and Debugging (continued)

25. Alice in Action with Java25 Coding the Other Actions say() message Displays dialog for an object Text can be customized by selecting other… Task: complete first Alice Liddell application Add Alice Liddell’s initial greeting Point the white rabbit to the user Have Alice Liddell introduce herself Have the white rabbit introduce himself Customize messages by selecting from more… Example: adjust fontSize of message text to 25

26. Alice in Action with Java26 Coding the Other Actions (continued)

27. Alice in Action with Java27 Statements/Instructions Statement/instruction: a line or control structure in a program that executes (is carried out by computer at runtime) Program: a set of instructions that tell the computer what to do Basic format of a line in an Alice program object.message(value); more... Control structures manage other statements Example: doInOrder contains other statements

28. Alice in Action with Java28 The Final Action Sequential execution Actions are performed consecutively Example: actions executed in doInOrder structures Simultaneous execution Actions are performed in parallel Example: actions performed in doTogether structure Finishing the first program Add doTogether control structure to application Send say( ) to aliceLiddell and whiteRabbit Message value: Welcome to our world

29. Alice in Action with Java29 The Final Action (continued)

30. Alice in Action with Java30 Final Testing First set of actions are performed separately Final actions are performed simultaneously

31. Alice in Action with Java31 Final Testing (continued)

32. Alice in Action with Java32 The Software Engineering Process A methodical, disciplined approach to constructing programs Multiple parts (problem specification,) design, implementation, testing (, revising..) Elements of software design Write the user story Organize nouns and verbs into an algorithm Create storyboard-sketches and the transition diagram Elements of software implementation and testing For each noun in the story, add an object to Alice world Match message to verb and send message to object Test message to determine if it produces desired action

33. Alice in Action with Java33 Alice’s Details Area Reflects attributes and behaviors of selected object Three panes: properties, methods, and functions

34. Alice in Action with Java34 The properties Pane Includes attributes such as color, opacity, visibility Change values to alter object appearance/behavior Example: make the White Rabbit disappear Click opacity in the properties pane Drag opacity to the editing area Set opacity to 0 Change the duration to 2 seconds How a program changes when a property is altered New message is added to editing area In the example above, a set () message is added

35. Alice in Action with Java35 The properties Pane (continued)

36. Alice in Action with Java36 The methods Pane Provides a list of behavior-generating messages In Object Oriented Programming, an instruction targeting an object is said to be a method. To get an object to perform a behavior, send that object a message that asks it to produce that behavior E.g. aliceLiddle.say(…)

37. Alice in Action with Java37 Methods Alice Objects have predefined methods for basic tasks Additional methods may also be created by Alice developers Two reasons for building your own methods To organize your story into more manageable pieces To provide an object with additional behaviors

38. Alice in Action with Java38 The methods Pane

39. Alice in Action with Java39 The functions Pane Provides list of information returning messages Differentiate functions from methods Functions return data, messages produce behavior Type of information returned by functions Proximity to another object Size in terms of height, width, or depth Spatial relation to another object Point of view (position and orientation in the world) Subparts world object responds to different set of functions

40. Alice in Action with Java40 The functions Pane (continued)

41. Alice in Action with Java41 Alice Tip: Positioning Objects Using Quad View Actions performed after pressing ADD OBJECTS Navigate the Alice Gallery Locate classes Use classes to add objects to the world Two views: single view and quad view quad view World window View from the top View from the right View from the front

42. Alice in Action with Java42 Alice Tip: Positioning Objects Using Quad View (continued)

43. Techniques and Tools Mouse is used to approximately position objects in the scene Camera Navigation is used to set the camera point of view Drop-down menu methods are used to resize objects more precisely position objects in the scene Quadview is used to position one object relative to another object

44. Alice in Action with Java44 Summary Alice: software tool used to create virtual worlds User story: prose description of program form the user’s point of view Shot: component of a scene with the camera at one viewpoint Algorithm: flow of actions that solves a problem Storyboard-sketch: drawing of a distinct screen in a computer application

45. Alice in Action with Java45 Summary (continued) Alice window: menus, buttons, object tree, details area, world window, editing area, and events area Class: blueprint for an object Method: behavior-producing message Function: message that returns information Software engineering encompasses software design, and implementation and testing

46. Assignment Read Chapter 1 Finish the programming assignments Farm scene Alice Book Prog. Project 1.9 or 1.10 (due by next Tuesday, demo on next Lab) Lab exercises and projects require you to demonstrate the code and execution of your programs to the instructor or a TA, in order to receive credits.

47. Lab Appendix A, Getting Started – Parts I & II Exercises from Chapter 1 Notes: Lab exercises and projects require that you demonstrate the code and execution of your programs to the instructor or the TA Your lab sheet must have the signature of the instructor or TA for each assigned exercise and/or project. Otherwise, you will not get credit for having completed the lab!

48. Demo: A new world Create a new world File  New Choose template

49. Demo: Adding objects

50. Objects An "object" is any thing that can be identified as unique from other things How is an object unique? has a name has properties: width, height, color, location can perform actions (methods): associated actions it can perform tasks it can carry out

51. Object Parts Objects may be composed of parts

52. Class Objects are categorized into classes Each object is an instance of the class. All objects in a class have similar properties and generally can perform the same tasks. Person Dogs peter mary paul spike scottie fluffy

53. Galleries Classes (3D models) are found in the galleries Local gallery (installed with the software) Minimum or complete options CD Gallery (only if CD is in the machine) Web gallery

54. Demo: Saving a world Writing and testing an animation is an intense load on the computing system – a crash can occur. Best solution: save your world every 15 minutes (Or at least every half hour) also save to a backup system (for example, a zip disk or memory key)