Global variables in Construct 3 are like containers that store information that can be accessed and modified throughout your entire game project. They hold data that you want to be available to different parts of your game (unlike local variables that are specific to a single event or instant variables which apply to a single instance).
Global variables are used to hold information such as:
- In a counting game we might use a global variable to keep track of the numbers as the player counts up.
- We might use a global area to run an end-of-game sequence, ie delete objects and create the ‘play again’ button.
- In an addition game we may have two global variables, one with the total, the other with the number the player has entered, and the two are compared to see if they player has the correct answer.
Here’s a more detailed breakdown of global variables:
- Scope: As the name suggests, they are global in the sense that they can be accessed and changed from any layout or event sheet in your project. This makes them useful for storing information that needs to be shared across different parts of the game.
- Data Types: Global variables can hold various data types like numbers (for scores, health points), text (for player names, level titles), or even booleans (true/false values for flags or switches).
- Add/Subtract: We can add and subtract to numbers in variables, change the variable or set the variable.
Here are some common use cases for global variables:
- Game State: Tracking the current score, health points, level number, or other gameplay-related data that needs to be consistent throughout the game.
- Configuration Settings: Storing options like sound volume, difficulty level, or player preferences that can be adjusted during gameplay.
- Flags and Triggers: Using boolean variables to indicate if certain events have happened (e.g., a challenge completed) to influence gameplay logic.
Here are some additional things to keep in mind about global variables:
- Overuse Caution: While convenient, using too many global variables can make your game logic complex and harder to manage. Consider local variables for information specific to a particular layout or event sheet.
- Naming Conventions: Use clear and descriptive names for your global variables to improve readability and maintainability of your code. Make use of the description box to remind you of how the variable is to be used. Read more about naming conventions HERE!
For a more in-depth look at creating and using global variables in Construct 3, you can refer to the official documentation: https://www.construct.net/en/forum/construct-classic/help-support-using-construct-38/global-variables-38846