跳转到内容

Creating collectibles in top-down scrolling games

此内容尚不支持你的语言。

💡 Having trouble with Scratch block assembly? Don’t know how to implement code logic? 🚀 Get Help Now

GD

GameDevExplorer

Posted on July 22, 2025 • Advanced

🎮 Mystery solved: Collectibles in top-down scrollers!

I’ve been working on a massive Zelda-style RPG and hit a wall with collectibles. Why don’t I see cloned collectibles in top-down scrolling games? Is it even possible?

I’ve studied tons of RPGs and Zelda remakes, but none seem to use cloning for collectibles like rupees. Even ChatGPT couldn’t help me figure this out! 😅

The main challenge is making collectibles scroll properly with the background while using clones. Regular collision detection works fine, but the scrolling mechanics break everything.

Has anyone cracked this code? I really want to create the first top-down scrolling RPG with properly cloned collectibles! Any insights would be amazing! 🙏

SM

ScrollMaster_Dev

Replied 3 hours later • ⭐ Best Answer

@GameDevExplorer I’ve actually solved this exact problem! The key is understanding how scrolling coordinates work with clones. Here’s the complete solution:

🗺️ Scrolling Collectibles System

Here’s how the system works:

flowchart TD A[🚀 Game Start] --> B[Create Collectible Clones] B --> C[Set World Positions] C --> D[🎮 Game Loop] D --> E[Update Scroll Position] E --> F[Calculate Screen Position] F --> G{Clone on Screen?} G -->|Yes| H[Show Clone] G -->|No| I[Hide Clone] H --> J{Player Touching?} J -->|Yes| K[💰 Collect Item] J -->|No| L[Continue Loop] K --> M[Play Sound] M --> N[Add to Inventory] N --> O[Delete Clone] I --> L O --> L L --> D style A fill:#e1f5fe style B fill:#f3e5f5 style K fill:#e8f5e8 style O fill:#ffebee

🔧 Step 1: Collectible Sprite Setup

First, create your collectible sprite with these sprite-only variables:

  • world_x - The item’s fixed world position
  • world_y - The item’s fixed world position
  • collected - Whether this clone was collected
    when flag clicked
set [clone_id v] to [0]
repeat [50] // Create 50 collectibles
change [clone_id v] by [1]
create clone of [myself v]
end
hide

💎 Step 2: Clone Initialization

Each clone needs to know its world position:

    when I start as a clone
set [world_x v] to (pick random [-2000] to [2000])
set [world_y v] to (pick random [-1500] to [1500])
set [collected v] to [false]
show

forever
// Calculate screen position based on camera scroll
set x to ((world_x) - (camera_x))
set y to ((world_y) - (camera_y))

// Hide if off-screen for performance
if <<(x position) < [-300]> or <(x position) > [300]>> then
hide
else
if <<(y position) < [-250]> or <(y position) > [250]>> then
hide
else
if <(collected) = [false]> then
show
end
end
end

// Check for collection
if <<touching [Player v]?> and <(collected) = [false]>> then
set [collected v] to [true]
change [rupees v] by [1]
play sound [collect v]
hide
stop [this script v]
end
end

🎮 Step 3: Camera/Scroll System

Your main game needs these global variables for camera control:

    // In your main game sprite or stage
when flag clicked
set [camera_x v] to [0]
set [camera_y v] to [0]

forever
// Follow player with camera
change [camera_x v] by (((player_x) - (camera_x)) / [10])
change [camera_y v] by (((player_y) - (camera_y)) / [10])
end

🚀 Step 4: Advanced Features

For even better performance and features:

Persistent Collection (Save System):

    // Save collected items to a list
when I receive [item collected v]
add (join (world_x) (join [,] (world_y))) to [collected_items v]

// Check if item was already collected
when I start as a clone
set [item_key v] to (join (world_x) (join [,] (world_y)))
if <[collected_items v] contains (item_key)?> then
set [collected v] to [true]
hide
end

Different Collectible Types:

    when I start as a clone
set [item_type v] to (pick random [1] to [3])
if <(item_type) = [1]> then
switch costume to [rupee v]
set [value v] to [1]
else
if <(item_type) = [2]> then
switch costume to [heart v]
set [value v] to [5]
else
switch costume to [key v]
set [value v] to [1]
end
end

The secret is treating world coordinates separately from screen coordinates! Each clone remembers where it belongs in the world, then calculates where to appear on screen based on the camera position. 🎯

GD

GameDevExplorer

Replied 45 minutes later

@ScrollMaster_Dev HOLY MOLY! 🤯 This is exactly what I needed!

I was trying to make the clones move with the scroll, but you’re right - keeping world coordinates separate from screen coordinates is genius! Testing this right now…

Update: IT WORKS PERFECTLY! My Zelda RPG finally has proper rupee collection! You’re a lifesaver! 🎉

RP

RPGMaster_Alex

Replied 2 hours later

This is why I love this community! 💪 @ScrollMaster_Dev just solved one of the trickiest problems in Scratch game development.

Pro tip: You can also use this same technique for enemies, NPCs, and interactive objects. The world/screen coordinate separation is the foundation of any good scrolling game!

Can’t wait to see your Zelda RPG @GameDevExplorer! 🗡️

VB

Vibelf_Community

Pinned Message • Moderator

🎮 Advanced Scrolling Game Development

Excellent problem-solving everyone! For those working on complex scrolling games, our tutors can help you master:

  • 🗺️ Advanced camera systems
  • 🎯 Efficient collision detection
  • 💾 Save/load systems
  • 🏰 Level design techniques
  • ⚡ Performance optimization

📚 Related Topics

Ready to create the next amazing Scratch RPG? Get expert guidance from our game development tutors!