Popcorn Hacks:

Develop a basic combat system that allows characters to engage in battles with enemies. This will help you practice using functions, conditionals, and basic game mechanics in JavaScript.

Popcorn Hack Part 1 - 1: Using initializeData Function
  1. Add speed to the initializeData(data = null) function and give it a default value.
  2. Add seed to the HTML output.
  3. Add speed to the JSON data.
  4. Test calling initializeData with no argument, and then using a data JSON object as an argument.
%%html

<output id="output1"></output>

<script>
function intializeData(data = null) {
    // Define default values
    let scaleFactor = 9/16;
    let animationRate = 1;
    let position = [0, 0];
    // add speed with default value 0
    let speed = 1;

    // Check if data is provided
    if (data) {
        scaleFactor = data.SCALE_FACTOR || scaleFactor;
        animationRate = data.ANIMATION_RATE || animationRate;
        position = data.INIT_POSITION || position;
        speed = data.SPEED || speed;
        
    }

    document.getElementById("output1").innerHTML = `
        <p>Scale Factor: ${scaleFactor}</p>
        <p>Animation Rate: ${animationRate}</p>
        <p>Initial Position: ${position}</p>
        <p>Initial Speed: ${speed}</p>
    `;
}

var data = {
    SCALE_FACTOR: 1/1,
    ANIMATION_RATE: 25,
    INIT_POSITION: [100, 100],
    SPEED: 10
}

// Uncomment one of the following lines to test the if statement in the function
//intializeData();
intializeData(data);

</script>
Popcorn Hack Part 1 - 2: Adding IJKL Key Conditions in handleKeyDown
  1. Add a case statement for each of the IJKL keys in the handleKeyDown({ keyCode }) switch statement.
  2. Send the key code for each IJKL key to the gameObject.handleKeyDown method.
  3. Use console.log() to output gameObject.
%%javascript

class GameObject {
    constructor() {
        this.velocity = { x: 0, y: 0 };
        this.direction = '';
        this.xVelocity = 1;
        this.yVelocity = 1;
    }

    handleKeyDown({ keyCode }) {
        switch (keyCode) {
            case 73: // 'I' key
                this.direction = 'up';
                break;
            case 74: // 'J' key
                this.direction = 'left';
                break;
            case 75: // 'K' key
                this.direction = 'down';
                break;
            case 76: // 'L' key
                this.direction = 'right';
                break;
        }
    }
}

// Example usage
const gameObject = new GameObject();
console.log('Initial State:', gameObject);

gameObject.handleKeyDown({ keyCode: 73 }); // Simulate 'I' key press
console.log('After I Key Press:', gameObject);

gameObject.handleKeyDown({ keyCode: 74 }); // Simulate 'J' key press
console.log('After J Key Press:', gameObject);

gameObject.handleKeyDown({ keyCode: 75 }); // Simulate 'K' key press
console.log('After K Key Press:', gameObject);

gameObject.handleKeyDown({ keyCode: 76 }); // Simulate 'L' key press
console.log('After L Key Press:', gameObject);

<IPython.core.display.Javascript object>
Popcorn Hack 2: Creating a Simple Attack System
  1. Add a boolean variable named canAttack, and set it to false.
  2. Use an if statement to check if the player can attack.
  3. If canAttack is false, output “Can’t attack.”
  4. Use Math.random() to determine if the player is allowed to attack. (Tip: Use ChatGPT for help with Math.random() if needed!)
  5. This will pick a random number to decide if the attack can happen.
  6. Use console.log() for all outputs.
%%js
let canAttack = false
if (canAttack){
    console.log("Can Attack")
}
else{
    console.log("Can't Attack")
}
canAttack = Math.random() < 0.5 ? true : false


if (canAttack){
    console.log("Can Attack")
}
else{
    console.log("Can't Attack")
} 

<IPython.core.display.Javascript object>
Popcorn Hack 3: Level Requirement Check
  1. Use the ternary operator to create an output if the player meets the level requirements.
  2. If not, output a message telling the player they are under-leveled.
  3. Use console.log() to print your output.
%%js
//No code provided so creating new sample code
//Random number is used to generate boolean flag using ternary operator
let metLevelRequirement = Math.random() < 0.5? true: false
if (metLevelRequirement){
    console.log("Met level requirement")
}
else {
    console.log("Did not meet level requirement")
}

<IPython.core.display.Javascript object>

Homework:

Objectives


Option 1: Create a simple combat system.

  • Allow characters to fight enemies.
  • Use basic functions and conditionals in JavaScript.
  • Focus on making it easy to understand how battles work.


Option 2: Make a dialogue system for your NPC (Non-Player Character).

  • Use the prompt() function to ask the player for a response (choose a number from 1 to 4).
  • This dialogue should appear when the player gets close to the NPC and presses a button.

</span>

Additional Tips:

  • For Option 1:
    • Start by writing down what the characters and enemies will be. Create simple names and attributes (like health).
    • Use console.log() to print out what's happening at each step. This will help you understand the flow of your code.
    • Look for example code online to see how others have created combat systems. Don't be afraid to borrow ideas!
  • For Option 2:
    • Plan out the dialogue options before you start coding. Write them down in a list.
    • Use comments in your code to remind yourself what each part does. For example, // Ask the player for a response.
    • Test your code frequently. After writing a few lines, run it to see if it works before adding more.
// NPC Dialogue System

// NPC initial dialogue when the player approaches
function npcDialogue() {
    // The dialogue options for the player to choose from
    const dialogues = [
        "Greetings, adventurer! Are you seeking knowledge or fortune?",
        "These parts are not for the faint-hearted. Are you well-prepared?",
        "Legends speak of a hidden treasure nearby. Are you interested?",
        "Be wary of strangers. Not everyone is as friendly as I am!"
    ];

    // NPC initial message
    alert("NPC: Ah, a new face in these lands! You look like someone with a story to tell.");

    // Display dialogue options to the player
    const response = prompt(
        "Choose a response:\n" +
        "1. 'I'm looking for adventure!'\n" +
        "2. 'I could use some guidance.'\n" +
        "3. 'Tell me more about this treasure!'\n" +
        "4. 'Thanks for the advice, I'll be careful.'"
    );

    // Handle the player's response based on their choice
    switch (response) {
        case "1":
            alert("NPC: Adventure awaits around every corner here. Keep your wits about you!");
            break;
        case "2":
            alert("NPC: The path ahead is treacherous. Seek the old sage in the village for wisdom.");
            break;
        case "3":
            alert("NPC: Rumor has it that the treasure lies beneath the ancient oak, guarded by puzzles.");
            break;
        case "4":
            alert("NPC: Wise choice. Trust only those you know. Good luck, traveler.");
            break;
        default:
            alert("NPC: Hmm, I didn’t quite catch that.");
    }
}

// Simulate the player getting close to the NPC and pressing a button
document.addEventListener("keydown", function(event) {
    // Assuming "E" key is the interaction key
    if (event.key === "E" || event.key === "e") {
        npcDialogue();
    }
});

  Cell In[1], line 1
    // NPC Dialogue System
    ^
SyntaxError: invalid syntax