Lingo Programming in Directors Language

1
Lingo Programming in Directors Language

• TECH2001 EPP2
• Jon Ivins

2
Reading for this lecture

• This is a stand-alone topic
• Read Chapter 1 of Peuple et al

3
Overview

• What is Lingo?
• Lingo Terms
• Verbose syntax
• Dot syntax
• THIS LECTURE IS AN INTRODUCTION TO LINGO NOT A
  PROGRAMMING COURSE!

4
LINGO

• Part of Director
• In-built programming language
• Own syntax
• Own semantics
• Code is attached to objects on screen, on the
  score or the cast
• This code can be simple or complicated!

5
LINGO TERMS (taken from Director Help File)

• Commands are terms that instruct a movie to do
  something while the movie is playing.
• Constants are elements that dont change.
• Events are actions that occur while a movie is
  playing.
• Expressions are any part of a statement that
  produces a value. For example, 2 2 is an
  expression.

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LINGO TERMS (taken from Director Help File)

• Functions are terms that return a value. For
  example, the date() function returns the current
  date set in the computer. The key() function
  returns the key that was pressed last.
  Parentheses occur at the end of a function.
• Handlers are sets of Lingo statements within a
  script that run when a specific event occurs in a
  movie. For example, the following statements
  comprise a handler that plays a beep sound when
  the mouse is clicked
• on mouseDown
• beep
• end

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LINGO TERMS (taken from Director Help File)

• Keywords are reserved words that have a special
  meaning. For example, end indicates the end of a
  handler.
• Lists are ordered sets of values used to track
  and update an array of data, such as a series of
  names or the values assigned to a set of
  variables. A simple example is a list of numbers
  such as 1, 4, 2.
• Messages are notices that Director sends to
  scripts when specific events occur in a movie.
  For example, when the playback head enters a
  specific frame, the enterFrame event occurs and
  Directors sends an enterFrame message. If a
  script contains an on enterFrame handler, the
  statements within that handler will run, because
  the handler received the enterFrame message.

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LINGO TERMS (taken from Director Help File)

• Operators are terms that calculate a new value
  from one or more values. For example, the
  addition () operator adds two or more values
  together to produce a new value.
• Properties are attributes that define an object.
  For example, picture is a property of a bitmap
  cast member.
• Statements are valid instructions that Director
  can execute. For example, go to frame 23 is a
  statement.
• Variables are elements used to store and update
  values. To assign values to variables or change
  the values of many properties, you use the equals
  () operator or the set command. For example, the
  statement set startValue 0 places a value of 0
  into a variable named startVal
• Variables can be local or global

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Scripts

• These are pieces of program code written in Lingo
• They are self-contained
• They can act on individual objects, groups of
  objects or over the whole movie
• Behaviour library is a collection of useful
  scripts

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Scripts

• Two types
• Verbose
• very much like English, easy to understand
  individual lines
• Hard to debug complicated scripts as lot of text
  to read
• x 2 2
• put string(x) into member "The Answer"
• Dot syntax
• Abbreviated format so easier to type
• Can switch between Verbose Dot as you wish
• Some commands only exist in Dot Syntax

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Verbose Syntax Examples

• set the stageColor to 255
• put the text of member "Instructions" after
• member "Introduction"
• if x5 then
• go to frame 22
• end if

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Dot Syntax example

• VERBOSE
• set the forecolor of sprite 12 to 155
• DOT
• sprite(12).forecolor 155

13
Testing Scripts ..if then else loops

• if the mouseMember memberNum("map 1") then
• go to "Cairo"
• else if the mouseMember member ("map 2") then
• go to "Nairobi"
• else
• alert "Youre lost."
• end if

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Testing Scripts..Cases

• on keyDown
• case (the key) of
• "A" go to frame "Apple"
• "B", "C"
• puppetTransition 99
• go to frame "Oranges"
• otherwise beep
• end case
• end keyDown

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More Cases

• This case statement tests whether the cursor is
  over sprite 1, 2, or 3 and runs the corresponding
  Lingo if it is
• case the rollOver of
• 1 puppetSound "Horn"
• 2 puppetSound "Drum"
• 3 puppetSound "Bongos"
• end case

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Tips to start programming

• Think about the order that the script has to do
  things
• Write down what you want to do in English then
  convert it to Lingo
• Make use of the help file most answers are in
  there!!
• Hierarchy charts, Flowcharts, Pseudo-code,
  decision trees tables are useful tools for code
  design

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References

• The Director Help File
• Macromedias knowledge base accessed from
  www.macromedia.com
• There are several good books in the library but
  none are recommended in their entirety