1. Quick Recap: Ricochet

What we built last time

What We Learned

The Next Step

This is the missing piece for Pong — how does the ball know it hit a paddle?

2. New Node: Area2D

How do we know when two things touch?

What is Area2D?

CollisionShape2D

Area2D needs a shape to know its boundaries

Common shapes: RectangleShape2D, CircleShape2D, CapsuleShape2D

We'll use RectangleShape2D — it matches our sprites

Node2D vs Area2D

Rule of thumb: if it needs to detect contact with something, use Area2D

3. Part A: The Basket

The player-controlled catcher

Basket Scene Tree

Same idea, but Area2D replaces Node2D and we add a CollisionShape2D

Step-by-Step Setup

1. Create new scene → root node: Area2D
2. Rename to Basket
3. Add child: Sprite2D → assign basket texture
4. Add child: CollisionShape2D
5. In Inspector: Shape → New RectangleShape2D
6. Resize rectangle to match sprite
7. Save as basket.tscn

The $ Shorthand

Getting Sprite Size

How wide/tall is my sprite on screen?

# Raw texture size (pixels in the image file)
var tex_w = $Sprite2D.texture.get_width()
var tex_h = $Sprite2D.texture.get_height()

# Actual display size (accounts for scale!)
var display_w = tex_w * $Sprite2D.scale.x
var display_h = tex_h * $Sprite2D.scale.y

Basket Script

extends Area2D

var speed = 400

func _process(delta):
    if Input.is_action_pressed("ui_left"):
        position.x = position.x - speed * delta
    if Input.is_action_pressed("ui_right"):
        position.x = position.x + speed * delta

    var half_w = $Sprite2D.texture.get_width() * $Sprite2D.scale.x / 2   # display half-width
    var screen_w = get_viewport_rect().size.x                           # viewport width
    position.x = clamp(position.x, half_w, screen_w - half_w)          # keep edges on screen

Look familiar? This is the Wanderer pattern!

• extends Area2D instead of extends Node2D
• Same Input.is_action_pressed() polling
• Same clamp() to stay on screen

Pattern Recognition

Learn once, use everywhere

4. Part B: The Fruit

The falling collectible

Fruit Scene Tree

Same structure as the Basket — Area2D with a shape and sprite

Both need Area2D because both need to detect overlap with each other

Fruit Script

extends Area2D

var speed = 200                                                         # pixels per second

func _ready():
    add_to_group("fruits")                                              # tag for collision check

func _process(delta):
    position.y = position.y + speed * delta                              # fall downward

    var half_h = $Sprite2D.texture.get_height() * $Sprite2D.scale.y / 2 # display half-height
    var screen_h = get_viewport_rect().size.y                           # viewport height
    if position.y > screen_h + half_h:                                  # fully below screen?
        queue_free()                                                    # destroy this fruit

New Concept: queue_free()

• Removes the node from the scene tree
• Frees the memory it was using
• "Queue" = happens safely at end of frame (not mid-process)
• Without this, off-screen fruits pile up forever → memory leak!

In Ricochet, logos bounced back. In Fruit Frenzy, missed fruits are destroyed.

5. Signals

Godot's Event System

What Are Signals?

Signals decouple the sender (what happened) from the receiver (what to do about it)

Signal Flow: Fruit Meets Basket

The area parameter is the other Area2D that entered — in our case, the Fruit

Connecting Signals in the Editor

1. Select the Basket node in the scene
2. Go to the Node panel (right side, next to Inspector)
3. Click the Signals tab
4. Double-click area_entered(area: Area2D)
5. Connect to Basket → method: _on_area_entered

Groups: Tagging Nodes

add_to_group("fruits")       # in _ready(): tag this node as a fruit
area.is_in_group("fruits")   # later: ask "is this node a fruit?"

The Handler Function

func _on_area_entered(area):
    if area.is_in_group("fruits"):                                      # is it a fruit?
        area.queue_free()                                               # destroy it
        get_parent().add_score()                                        # tell Game we scored

get_parent() Communication

This works because the Basket knows its parent has an add_score() function

6. Game Scene: Spawning + Score

Putting it all together

Game Scene Tree

1. New scene → root: Node2D → rename to Game
2. Drag basket.tscn into scene → position at (400, 550)
3. Add child: Label → rename to ScoreLabel → text: Score: 0
4. Add child: Timer → rename to SpawnTimer
5. Save as game.tscn

New Node: Timer

• wait_time — seconds between each tick
• start() — begin the countdown
• timeout signal — emitted every time the timer fires

Perfect for spawning a fruit every second!

Game Script

extends Node2D

var fruit_scene = preload("res://fruit.tscn")                           # load once at startup
var score = 0

func _ready():
    $SpawnTimer.wait_time = 1.0                                         # spawn every 1 second
    $SpawnTimer.start()                                                 # begin the countdown
    $SpawnTimer.timeout.connect(_on_spawn_timer_timeout)                # signal → function

func _on_spawn_timer_timeout():
    var fruit = fruit_scene.instantiate()                               # create a new fruit
    var screen_w = get_viewport_rect().size.x                           # viewport width
    var margin = 50                                                     # edge padding
    fruit.position = Vector2(randf_range(margin, screen_w - margin), -20) # random x, above screen
    add_child(fruit)                                                    # add to scene, starts falling

func add_score():                                                       # called by Basket on catch
    score = score + 1
    $ScoreLabel.text = "Score: " + str(score)                           # update the UI

Code Walkthrough

preload("res://fruit.tscn") — load the fruit scene (from Ricochet!)

$SpawnTimer.wait_time = 1.0 — spawn every 1 second

$SpawnTimer.timeout.connect(...) — connect signal in code (alternative to editor)

fruit_scene.instantiate() — create a new fruit copy (from Ricochet!)

Vector2(randf_range(50, screen_w - 50), -20) — random x, just above screen

add_child(fruit) — add to scene tree, fruit starts falling

$ScoreLabel.text = "Score: " + str(score) — update the UI

Two Ways to Connect Signals

We used the editor for Basket's area_entered

We used code for Timer's timeout

Both do the same thing — connect a signal to a function

Run It!

Fruits fall. Catch them. Score goes up.

A complete game in ~30 lines of code!

7. Bonus: Fruit Variety

Adding visual flair

Random Colors & Speeds

Add to the Fruit script's _ready():

func _ready():
    add_to_group("fruits")                                              # tag for collision check
    $Sprite2D.modulate = Color(randf(), randf(), randf())               # random color tint
    speed = randf_range(150, 350)                                       # random fall speed

• $Sprite2D.modulate — same trick from Ricochet's color bonus!
• randf_range(150, 350) — each fruit falls at a different speed
• Each instantiate() calls _ready() → unique fruit every time

Summary: What We Learned

New Concepts

The Journey So Far

Exercises

Try these on your own!

Beginner

1. Speed Experiment: Change the fruit's fall speed from 200 to 400, then 100. What makes the game fun? What about the basket speed?
2. Miss Counter: Add a misses variable to the Game script. When a fruit calls queue_free() because it went off screen (not caught), tell the game. Display "Missed: X" in a second label.
3. Spawn Rate: Make fruits spawn faster over time. Every 10 seconds, reduce $SpawnTimer.wait_time by 0.1 (minimum 0.3). Hint: use a second Timer.

Intermediate

4. Fruit Types: Create 3 different fruit scenes with different colors and point values. Red = 1 point, gold = 3 points, rainbow = 5 points. Randomly pick which to spawn.
5. Power-Up: Every 15 seconds, spawn a special "growth" item. When caught, the basket's CollisionShape2D gets 50% wider for 5 seconds. Hint: use $CollisionShape2D.shape.size

Advanced

6. Falling Bombs: Spawn red "bomb" Area2Ds alongside fruits. Catching a bomb subtracts 3 points. Hint: add bombs to a "bombs" group and check area.is_in_group("bombs")
7. Game Over: Add 3 lives. Missing a fruit loses a life. At 0 lives, stop the spawn timer and show "Game Over" text. Add a restart button using _input(event).