Game Programming I

1
Game Programming I

• MULT 110
• Week 5
• All About ActionScript! Again.

2
Review - Question 1

• You have a Dynamic Text field in Flash named
  feedback_txt
• How do you set it to display the message
• Youve Won! Play again?

3
Review - Question 1

• You have a Dynamic Text field in Flash named
  feedback_txt
• How do you set it to display the message
• Youve Won! Play again?

feedback_txt.text Youve Won! Play again?
4
Review - Question 2

• You have a variable names totalPoints which
  stores how many points a player has earned in
  your game.
• If theyve earned more then 50 they have won the
  game.
• How do you code to check whether or not they have
  won?

5
Review - Question 2

• if (totalPoints 50)
• //They Win
• Do Something
• else
• //They Lose
• Do Something

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if Statement

• if (condition)

• Example
• if (answer "Option 2")
• gotoAndPlay("CorrectAnswer", 1)
• else
• gotoAndPlay("IncorrectAnswer", 1)

7
miniLab1 - 5 Minute Lab

• Create a flash Movie
• In frame 1 create an input text box
• Use a button from the common library
• When the button is clicked evaluate if the number
  in the text box is greater then 5
• Use traces to check your work

8
Review Question 3

• The Switch Statement
• What is it?
• Why do we need it?
• How does it work?

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Review Question 3

• switch (condition)
• case value
• actions
• break
• case value
• actions
• break
• default
• actions

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miniLab2 - 5 Minute Lab

• Duplicate your scene from miniLab1
• Replace the if statement with a switch statement
  that evaluates if red, blue or green was entered
  the text box.
• If anything else was entered have the trace
  display you didnt enter the right color

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Review Question 4

• What is this?
• What is it doing?
• What is i?

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miniLab3 - 5 Minute Lab

• Duplicate your scene from miniLab2
• Create a loop that runs 25 times when the button
  is clicked
• Every time the loop runs display a random number
  with the trace function
• Now add text to the trace that says x I am
  random number n2 I am random number 10

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Review Question 5

• Objects
• Methods
• Properties
• Event Methods

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miniLab4 - 5 Minute Lab

• Create a new scene
• Create a new movie clip symbol
• Create an onEnterFrame event that pulls a random
  number

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Arrays

• A collection or set of information that has some
  relationship
• All of these items are named the same and
  arranged in a list
• Each item, called an element, is accessed by its
  location in the list.
• The location is a number called the index.

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Example of an Array

• Name the array PlayerNames
• Lets put 4 names into the list
• Jane PlayerNames0
• Wayne PlayerNames1
• Dane PlayerNames2
• Lane PlayerNames3
• Visually
• PlayerNames

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The Array Object

• An Object preset with methods and properties
• To declare an array, generate a new object
• myArray new Array(4)
• To populate an array, name or assign the elements
• myArray Jane, Wayne, Dane, Lane
• or
• myArray0 Jane
• myArray2 Dane
• myArray3 Lane
• myArray1 Wayne

Note that the order of assignment matters here,
but not here.
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Array Object Methods

• Items may be collected into a single string
• myArray.join( )
• Easy way to test your arrays
• trace(myArray.join( ))
• Items in the array may be sorted
• myArray.sort( )
• Length of the array may be queried
• numberElements myArray.length

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Dynamic Arrays

• Need not declare the number of elements in an
  array
• dynamicArray new Array( )
• Add elements with a push
• dynamicArray.push(new one, another new one )
• Elements are added on to the end of the array
• Number of elements is passed back as a value
• Delete elements with a pop
• dynamicArray.pop( )
• Last element is deleted but passed back as a
  value.

20
miniLab5 - 5 Minute Lab

• Create a new scene
• Declare an Array called players
• Populate the array with 4 player names
• Randomly select a play and display the name using
  a trace
• Try other Methods see what happens
• How can you display the each element in the
  array?

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Matrix A Multidimensional Array

• You create multidimensional arrays in
  ActionScript by constructing an array, the
  elements of which are also arrays.

myMatrix12 holds Score 2
MyMatrix
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Matrix A Multidimensional Array

• A list of lists An array within an array
• myMatrix new Array( )
• myPlayers new Array(4)
• myScores new Array(4)
• myMatrix myPlayers, myScores
• myMatrix which arraywhich element

MyMatrix
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Matrix A Multidimensional Array

• To access elements of a multidimensional array,
  you can nest the array access operator with
  itself, as in the following
• // create the array
• var chessboard new Array()
• for (var i0 i
• chessboard.push(new Array(8))
• // reference the array
• function getContentsOfSquare(row, column)
• chessboardrowcolumn

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Example with Deck of Cards

• suits new Array(4)
• values new Array(13)
• // assign values
• suit "Clubs", "Diamonds", "Hearts",
  "Spades"
• value "2","3","4","5","6","7","8","9","10","J"
  ,"Q","K","A"
• cards new Array()
• // create matrix for deck of cards, 4 suits of
  13 cards
• for (i0 i
• cards.push(new Array(13))

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Chapter 8 and Individual Games

• We are going to look at the game samples in
  Chapter 8.
• Pick your favorite one and modify for your
  individual game
• Modifications must be done to the actionScript as
  well as Visual.
• Ideas
• Scoring
• Levels
• Cursors
• Audio
• Fix broken games
• Create New Game Based on engine