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Control the execution of code with common logic structures 

Level 1 Application Scripting

Joy Horvath

Instructional Designer

This quiz will assess your understanding of the concepts covered in the Create with Code 2 Mission.

Implement simple logic in code by using if and if-else statements

Control the execution of code by using logical operators such as AND and OR in conditional statements

Control how many times certain lines of code run by using for loops, foreach loops, and while loops

Control the order and timing of executed code by using coroutines

Control the execution of code by using switch statements

Modify the values of numeric variables by using mathematical operators

Control the execution of code with common logic structures

Select the appropriate common Unity methods to use, e.g., Awake, Start, Update, FixedUpdate, Collision, and Trigger Events, given a desired feature to code

Achieve a desired result by using Unity API methods, given Unity’s script documentation

Achieve a desired result with different parameters by using various method overloads

Distinguish a correct use of any given Unity API method from an incorrect use

Control or trigger the state of components, such as an Animator Controller, Light, AudioSource, or User Interface element by using appropriate methods

Construct an input listener, given a scenario where a specific type of input is required

Print a message consisting of concatenated strings and variable values to the console by using Unity's Debug.Log method

Compose scripts that utilize various APIs

Initialize variables of a given data type, including ints, floats, doubles, bools, strings, arrays, lists, and dictionaries

Select the correct data type for a variable in a given situation

Select appropriate variable modifiers including public, private, static, protected, and const

Implement appropriate data types

Deduce the purpose and expected result of a given block of code

Accomplish a specific task by constructing a viable method declaration, given a list of keywords and syntax elements

Structure methods by using void and return

Demonstrate ability to implement a given feature in code by recommending data types and logic flow for a new method

Write code that integrates into an existing system

Given a particular feature description (e.g. an object spawner, a difficulty select menu, a loading screen, etc.), recommend an appropriate high-level system for its implementation (e.g. what data types would be required, what would be the logic flow, etc.)

Evaluate the efficacy of a finished prototype based on its design criteria

Prototype new concepts

Reduce redundancy and improve code's readability by correctly naming variables and methods

Describe common naming conventions including PascalCase and camelCase

Cultivate a code style that is efficient and easy to read

Use common logic structures to control the execution of code. 

Write code that utilizes the various Unity APIs

Choose and correctly implement appropriate data types 

Use a code style that is efficient and easy to read

 Recognize object-oriented vs data-oriented code

Diagnose and fix code that compiles, but fails to perform as expected

Diagnose and fix compilation bugs related to Unity’s Scripting API

Diagnose and fix the cause of an exception

What debug message would be logged to the console if Random.Range returned a value of 8?

int randomInt = Random.Range(0,10);
if(randomInt <= 3)
{
   Debug.Log("Low");
}
else if(randomInt > 8)
{
   Debug.Log("High");
}
else
{
   Debug.Log("Medium");
}

What debug message would be logged to the console if Random.Range returned a value of 8?  int randomInt = Random.Range(0,10);
if(randomInt <= 3)
{
   Debug.Log("Low");
}
else if(randomInt > 8)
{
   Debug.Log("High");
}
else
{
   Debug.Log("Medium");
}  

Since the value of 8 is NOT lower or equal to 3 (<= 3) and 8 is NOT greater than 8 (> 8), the final “else” statement would be true and “Medium” would be logged to the console.

Which of the following conditions would successfully print “Success”?

if (true && !false) { print(“Success”); }

if (true || false) { print(“Success”); }

if (true && !true) { print(“Success”); }

if (false || !true) { print(“Success”); }

Which of the following conditions would successfully print “Success”?  if (true && !false) { print(“Success”); } if (true || false) { print(“Success”); } if (true && !true) { print(“Success”); } if (false || !true) { print(“Success”); }  

For an && condition to be true, both booleans must be true. For an || condition, only one boolean of the two must be true. The NOT operator (!) flips the value of the boolean.

What code should go in the blank below in order to make the console print “First String” “Second string” “Third string”?

string[] strings = new string[3];
 
strings[0] = "First string";
strings[1] = "Second string";
strings[2] = "Third string";
 
foreach (__________)
{
    print (item);
}

What code should go in the blank below in order to make the console print “First String” “Second string” “Third string”?  string[] strings = new string[3];
 
strings[0] = "First string";
strings[1] = "Second string";
strings[2] = "Third string";
 
foreach (__________)
{
    print (item);
}  

In order to use a foreach loop, you need to reference the type (string), then declare a new name for that variable (item), then reference the actual list or array variable name (“strings”).

What will appear in the console if the following code is run?

void Start()
{
    StartCoroutine(MyCoroutine());
}

private IEnumerator MyCoroutine()
{
 yield return new WaitForSeconds(5);
    Debug.Log("Test");
   StartCoroutine(MyCoroutine());
}

What will appear in the console if the following code is run?  void Start()
{
    StartCoroutine(MyCoroutine());
}

private IEnumerator MyCoroutine()
{
 yield return new WaitForSeconds(5);
    Debug.Log("Test");
   StartCoroutine(MyCoroutine());
}  


“Test” will never appear because of an error in the code

“Test” will appear at start and then after 3 seconds.

“Test” will appear after 5 seconds and will continue to appear every 5 seconds after that.

The Coroutine is called at start, which then waits 5 seconds, logs “Test” and then calls the Coroutine again. This will start the cycle again to log “Test” every 5 seconds indefinitely.

What code would you use to fill in the blank in order to print “Incorrect dialogue value” to the console? 

int dialogue = 3;

void Start()
{
   _______________
   {
      case 2:
         print("Goodbye, old friend");
         break;
      case 1:
         print("Hello there");
         break;
      default:
         print("Incorrect dialogue value");
         break;
   }
}

What code would you use to fill in the blank in order to print “Incorrect dialogue value” to the console?   int dialogue = 3;

void Start()
{
   _______________
   {
      case 2:
         print("Goodbye, old friend");
         break;
      case 1:
         print("Hello there");
         break;
      default:
         print("Incorrect dialogue value");
         break;
   }
}  

A switch statement begins with the keyword “switch” and then the variable name that dictates the case in parentheses (dialogue). 

When the player object collides with a coin object, the coin object should instantly disappear without impacting the player object’s physics. Which event function should you use to detect the collision between these two objects in order to destroy the coin?

Since the coin would be a trigger, not responding to physics, OnTriggerEnter would detect the first collision between the player and the coin.

According to Unity’s scripting API, the following are valid options for the Component.GetComponent method:

public Component GetComponent(Type type);
public Component GetComponent(string type);

Which of the following would be a correct implementation of this method?

According to Unity’s scripting API, the following are valid options for the Component.GetComponent method:  public Component GetComponent(Type type);
public Component GetComponent(string type);  Which of the following would be a correct implementation of this method?  

A valid option for this method is to pass a single string parameter, as in  (“Player”);. If you want to specify a type, it would have to be between angle bracket <> and be followed by parentheses, as in <Player>();

According to the Unity Scripting API, the following are valid options for the Transform.Translate method:

public void Translate(Vector3 translation);
public void Translate(Vector3 translation, Transform relativeTo);
public void Translate(float x, float y, float z);
public void Translate(float x, float y, float z, Transform relativeTo);

Which of the following method calls would result in an error?

According to the Unity Scripting API, the following are valid options for the Transform.Translate method:  public void Translate(Vector3 translation);
public void Translate(Vector3 translation, Transform relativeTo);
public void Translate(float x, float y, float z);
public void Translate(float x, float y, float z, Transform relativeTo); Which of the following method calls would result in an error?  

transform.Translate(0f, 0f, 90f, gameObject.transform);

There is no method overload that would allow for the parameters (Vector3, float), which is the one that would cause an error (Vector3.up, 90f). All the other parameter combinations are listed.

Given the animation transition shown below, which code will make the character transition from the “Idle” state to the “Walk” state?

You can see in the inspector that the condition for this transition is that “Speed_f is greater than 0.25”. You can tell it’s a float because it uses decimal points and it must be higher than 0.25.

According to Unity’s Scripting API, the following is a valid option for the Input.GetButtonDown method:

public static bool GetButtonDown(string buttonName);

Let’s say you wanted to launch a projectile when the user presses the “Fire1” button, what would you put in the blank below:

public GameObject projectile;
void Update()
{
  if (__________) 
    Instantiate(projectile, transform.position, transform.rotation);
}

According to Unity’s Scripting API, the following is a valid option for the Input.GetButtonDown method:  public static bool GetButtonDown(string buttonName);  Let’s say you wanted to launch a projectile when the user presses the “Fire1” button, what would you put in the blank below:  public GameObject projectile;
void Update()
{
  if (__________) 
    Instantiate(projectile, transform.position, transform.rotation);
}  

To access the method within the Input class, you must first type Input.___. The GetButtonDown method accepts a single string parameter, such as “Fire1”.

The script below is attached to the Player GameObject in the scene. What would be displayed in the Console as a result of the code below?

public class PlayerManager : MonoBehaviour
{
 string playerName = "Frank";
 void Start()
  {
    Debug.Log("Hello: " + gameObject.name + playerName);
  }
}

The script below is attached to the Player GameObject in the scene. What would be displayed in the Console as a result of the code below?  public class PlayerManager : MonoBehaviour
{
 string playerName = "Frank";
 void Start()
  {
    Debug.Log("Hello: " + gameObject.name + playerName);
  }
}  

The code “gameObject.name” will return the name of the object that the script is on, which in this case, is “Player”. Since there is no space between gameObject.name and playerName, the result would be “PlayerFrank”

Which of the following is NOT true about data types?

bools can only have two values: true or false.

It is easier to increase the size of an array at runtime than it is for lists.

Using a dictionary, you can look up elements with strings, but with arrays or lists, you can only look up elements with integers.

It is actually much easier to increase the size of a list at runtime than it is for an array.

Which of the following variables is NOT initialized correctly?

List<GameObject> objectList = new List<GameObject>();

GameObject[] objectArray = new GameObject[];

Dictionary<string, GameObject> objectDict = new Dictionary<string, GameObject>();

Which of the following variables is NOT initialized correctly?  List<GameObject> objectList = new List<GameObject>(); GameObject[] objectArray = new GameObject[]; Dictionary<string, GameObject> objectDict = new Dictionary<string, GameObject>(); bool isTrue = true;  

When initializing a new array, you need to specify the size of the array within the square brackets, so it would need to be something like “= new GameObject[5];”

Which of the following is NOT true about variable modifiers?

Constant (const) variables cannot be modified after they have been initialized.

Private variables cannot be accessed from other classes.

Protected variables can only be accessed from static classes.


Public variables can be accessed from any class.

Protected variables can only be accessed by the containing class or classes that derive from that class.

What would be the result of the following code?

public class ExampleClass : MonoBehaviour
{
 void Start()
  {       
   SceneManager.LoadScene(Random.Range(0, SceneManager.sceneCount));
  }
}

What would be the result of the following code?  public class ExampleClass : MonoBehaviour
{
 void Start()
  {       
   SceneManager.LoadScene(Random.Range(0, SceneManager.sceneCount));
  }
}  

Provide a random number for the currently loaded scene.

Load a random range of scenes from all available scenes

Randomly arrange the scenes within the Scene Manager

Load a random scene from all currently loaded scenes

Random.Range is generating a random number between 0 and the total number of loaded scenes. The LoadScene method is then using that random number to load the scene.

In order to construct a method that takes a number and returns a duplicate of that number rounded to the nearest integer, what code would you put in the following blanks, in order of appearance:

_____ DuplicateNumber(float _____)
{
  number *= 2;
 int newNumber = Mathf.RoundToInt(number);
  _____ newNumber;
}

In order to construct a method that takes a number and returns a duplicate of that number rounded to the nearest integer, what code would you put in the following blanks, in order of appearance:  _____ DuplicateNumber(float _____)
{
  number *= 2;
 int newNumber = Mathf.RoundToInt(number);
  _____ newNumber;
}  

The first blank is “int”, since it should return an “int” value. The second blank is “number”, since this is the name of float variable that is then used in the method. The third blank is “return”, since you need to return that int variable.

What should be the method declaration to fill in the blank below, which should return the higher of two imputed float values?

_____________________
{
 float result;
 if (num1 > num2)
    result = num1;
 else
    result = num2;
 return result;
}

What should be the method declaration to fill in the blank below, which should return the higher of two imputed float values?  _____________________
{
 float result;
 if (num1 > num2)
    result = num1;
 else
    result = num2;
 return result;
}  

It returns a float so the first word (return type) should be “float.” The method takes two float type parameters named “num1” and “num2”, so within the parentheses, it requires “float num1, float numfloat num1, float num2”.

You want to create a loading scene sequence that works as follows. On a level select screen, there are a number of buttons, each corresponding to a different level. When the user clicks a level, you want to bring up a new loading screen, which displays the level number you selected, and after 5 seconds loads the scene corresponding to that level. How would you implement this, at a high level?

When the user clicks a button, store the level number as a private float variable, then load the loading scene. In the loading scene, use the InvokeRepeating method to delay the loading of the level using that integer variable.

When the user clicks a button, store the level number as a public integer variable, then load the loading scene. In the loading scene, use a Coroutine to delay the loading of the level using that integer variable.

When the user clicks a button, add the level number to a private list, then load the loading scene. In the loading scene, use the DontDestroyOnLoad method to delay the loading of the level.

For level numbers, it makes sense to store them in a public integer variable, since they do not require decimals and needs to be accessed from the loading screen. Coroutines allow you to delay the running of code by a number of seconds, so it makes sense to use a Coroutine to delay the loading of the selected level.

Which of the following guidelines about the use of variables and methods is NOT true?

Variable names should be longer and include complete words rather than being shorter (e.g. “int secondsElapsed” would be better than “int secElpsd”).

Methods names should usually include a verb or action in them (e.g. “void GenerateRandomObject” would be better than “RandomObject”).

Methods should usually do two or three things - if there are methods that only do one thing each, it makes sense to combine them. 

When naming booleans, use common words like ”is”, “has”, and “can” (e.g. “isRaining”, “hasStarted”, “canMove”) to indicate that it is a boolean.

Which of the following guidelines about the use of variables and methods is NOT true? Variable names should be longer and include complete words rather than being shorter (e.g. “int secondsElapsed” would be better than “int secElpsd”). Methods names should usually include a verb or action in them (e.g. “void GenerateRandomObject” would be better than “RandomObject”). Methods should usually do two or three things - if there are methods that only do one thing each, it makes sense to combine them.  When naming booleans, use common words like ”is”, “has”, and “can” (e.g. “isRaining”, “hasStarted”, “canMove”) to indicate that it is a boolean.  

As a rule, methods should usually only do one thing each.

The code snippet below is using Unity’s Entity Component System (ECS) as opposed to the more standard object-oriented framework.

using System;
using Unity.Entities;

namespace Shooter.ECS
{
    [Serializable]
    public struct MoveSpeed : IComponentData
    {
        public float Value;
    }

    public class MoveSpeedComponent : ComponentDataWrapper<MoveSpeed> { }
}

True or False:  The code snippet below is using Unity’s Entity Component System (ECS) as opposed to the more standard object-oriented framework.  using System;
using Unity.Entities;

namespace Shooter.ECS
{
    [Serializable]
    public struct MoveSpeed : IComponentData
    {
        public float Value;
    }

    public class MoveSpeedComponent : ComponentDataWrapper<MoveSpeed> { }
}  

You can tell this class is using ECS because its use of the Unity.Entities namespace, its implementing of IComponentData, and its structuring of code around data like MoveSpeed rather than objects. 

Quiz: Create with Code 2

Scripting

Aaron Sharp

For an && condition to be true, both booleans must be true. The NOT operator (!) flips the value of the boolean.

if (true && false) { print(“Success”); }

if (false && !true) { print(“Success”); }

In order to use a for loop, you need to reference the array variable name (“strings”) and access each element by its index variable (“i”) inside square brackets.

In an if / else if / else statement, the computer checks each condition in order. If none of the if or else if conditions are true, then the code inside the else block will execute.

Unity Version 6.0