Creating a 3D Interactive Story Prof. Susan Rodger Duke University Feb. 24, 2007

Now Create an Alice World Start Alice Select “File”, “New World” Click on Snow picture Click on “Open”

Find SnowPeople objects Click on “add objects” Scroll over to “people” folder and click on it Scroll over to Snowman and snowWoman

Add Snowman to World Click on snowman and you will see: Click on “Add instance” Snowman appears in world

Add SnowWoman to world and adjust Click on SnowWoman and add her to the world Click on arrow key Click and hold on snowman to move him left and back Click and hold on snowWoman and move her to the right Scene should look like

Save World Save world Type in a name such as: snowPeople and then “save” Alice will remind you to save your work every 15 minutes

Now Ready to program! Click on done Should now see myFirstMethod

Write code to move the snowman This is the object tree, a list of all your objects in the world Now click on the word “snowman” to highlight it You should see methods below it (things the snowman can do) such as move, turn, roll, … Scroll down til you see “turn to face”

Write code to move the snowman (2) Click left mouse button on “snowman turn to face” AND HOLD IT DOWN, then Drag it over and release the mouse button Click on “snowWoman” “the entire snowWoman”

Write code to move the snowman (3) Code appears Click on Play

Have the snowman talk Drag over “Snowman Say” Select “other” and type a greeting such as “Hello there! Code is now: Play again

Now SnowWoman will act Click on snowWoman to see her methods Drag over code and drop below other code Play!

Now write a NEW snowman method Click on snowman Should see snowman’s methods Click on “create new method” and enter name “getAttention” Empty method is created, ready for you to enter code

Write GetAttention Method Add the following code to this method Note you now have two methods: Click on myFirstMethod to get back to it

Add getAttention method to program – to myFirstMethod Click on play

Repetition Sometimes you want to repeat commands Let’s repeat “getAttention” three times Click on “loop” and drag and drop at the end of our code, below getAttention –Select “other” and type 3 –Click on left tab of “getAttention and move it inside the loop –Now Play!

Create snowman method - popHat Click on snowman in objectTree select “create new method” and name it popHat

Want the “topHat” part of snowman Click on + by snowman Click on + by head click on tophat to highlight it

Now we will move just the tophat Drag over the “move” command twice to make the tophat move up and then down the same amount

Make an Event We want the hat to move up and down whenever we press the “H” key Create a new event and select “when a key is typed” Click on “any key” and select the “letters” then “H” Click on “nothing” and select “snowman” “popHat”

Making an Event happen Play your world Whenever you want the hat to pop up and down, just press the key “H”

Add more code to myFirstMethod At the end of your code in myFirstMethod –Add code to have the snowWoman turn toward the snowman, say “I said hello” and turn back Remember to click on the word snowWoman in the objectTree to get snowWoman methods

Here is one possible way

Turn SnowWoman’s Head red In addition to methods, each object also has properties you can drag and change Select “SnowWoman’s Head in the object tree Select the Properties tab

Turn SnowWoman’s Head Red (2) Click on color, hold and drag to right before snowWoman says “I said hello” Select color “red” and release, results in:

At end, turn head back to “no color” Here are the two color statements added to the code (note: “no color shows as white”) Play your world

Write a snowman Flip method Make sure you select “snowman” in the objectTree Create the method named “flip” Have the snowman do the following –Move up 1 meter –Roll left 2 revolutions –Move down 1 meter Add code at the end of myFirstMethod –Snowman says “Watch what I can do” –SnowWoman turns to look at him –Call the snowman flip method Play your world

Write a snowWoman flip method Make sure you select “snowWoman” in the objectTree, then create the method “flip” Have the snowWoman do the following –Move up 1 meter –Drag up a DoTogether from the bottom

Write a snowWoman flip method (2) Inside the DoTogether you can put commands that will happen at the same time Inside this DoTogether have the snowWoman do the following: –Turn forward 1 revolution –Resize by half Below drop in another DoTogether with: –Turn forward 1 revolution –Resize by 2 (back to the right size) Add one more command to move snowWoman down 1 meter

Now let’s call the SnowWoman flip method Add code at the bottom of myFirstWorld –SnowWoman should say “Watch what I can do” –Call the snowWoman flip method Play your world

Here is what flip should look like

Add two new events Add an event so the snowman flips when M is pressed Add an event so the snowWoman flips when W is pressed Play the world, press M and W anytime

Add more objects to the world First let’s add two more objects Click on “Add objects”, find the “nature folder” and add any tree to the world Click on it and push it far back Find the “vehicles” folder and find the scooter, add it to the world (you may have to look in the Web gallery to find the scooter)

Adjust the scooter Click on the third control and try turning the scooter around to face this direction Then click on the first control (the arrow) and push the scooter back between the tree and the snowWoman

Write the SnowWoman method driveAway First select the snowWoman in the objectTree and create a new method named “driveAway” Now let’s add code to this method First have the snowWoman turn to face the backRightFloor (or may be called RightFloor) part of the scooter

Move SnowWoman to the scooter It will be handy to test this method as we build it, look at the event “When the world starts” Click on the white arrow and select “snowWoman.driveAway” Now when the world starts, only this method will play – Click Play and see

Write snowWoman driveAway (2) We want the snowWoman to move to the scooter.backRightFloor, but we don’t know how far it is Have the snowWoman move forward 1 meter and Play it It’s not quite far enough

Write snowWoman driveAway (3) We can use a snowWoman function to drop in the distance to the scooter.backRightFloor Click on SnowWoman functions Drag “distance to” and drop on “1 meter” when it turns green, then select “scooter.backRightFloor”

Write snowWoman driveAway (4) Play the world It is hard to tell, but she goes right into the scooter. We’d like her to stop in front of the scooter. Click on the last arrow and select “math”, then “minus” then “0.5” Now she stops 0.5 meters in front of it

Write snowWoman driveAway (5) Next, have the snowWoman doTogether –move up 0.2 meters –Move forward 0.5 meters We’d like the scooter to move and have the snowWoman move with it We can set the vehicle property of the snowWoman to be the scooter

Write snowWoman driveAway (6) Click on snowWoman’s properties Drag over “vehicle” and select “scooter”

Write snowWoman driveAway (7) Almost done, add a few more commands In a DoTogether –The snowWoman says “Bye” –The scooter moves forward 10 meters –The snowman’s head turns ¼ turn to the left (make sure you select snowman in the objectTree) One more command after the DoTogether –Snowman’s head turns back ¼ turn to the right

snowWoman driveAway – final code

Call snowWoman driveAway Back in myFirstMethod, add a call at the end of your code to call the method snowWoman.driveAway Fix the first event so that when the world starts, world.myFirstMethod is called Play

Write a snowman melt method Add a snowman method named “melt” The code should repeat 12 times –Move the snowman down a little (0.1 meters) –Wait 0.5 seconds (drag the “wait” tile up from the bottom) At the end of myFirstMethod, call melt Play the world

Almost Done – add title Click on “add objects” and go to the right end of the local gallery and find 3D text Click on it and add a short title such as “Life as SnowPeople” You’ll have to use the control keys to move it up, back, and turn it to face the right way (use first three controls)

Title only in the beginning Notice the title is an object in the objectTree - Click on it We would like it to disappear after the snowman says “hello there” Drag over the “isShowing” property and set it to false

Add “The End” Add another 3D text that says “The End” and position it over the title Click on THE END in the objectTree In properties, click on “true” of “isShowing” and select “false” – The End will disappear

Make “The End” Reappear Make “The End” visible before the snowman melts

You are now done! Play your world! You can download Alice for free at My web page