Item System & Inventory - Godot 4

Introduction

This tutorial focuses on creating a drag-and-drop grid-based inventory system in Godot 4. By following these steps, you'll learn how to implement an item system using various assets and code snippets. This tutorial is particularly useful for game developers looking to manage items effectively in their games.

Step 1: Setting Up Your Project

• Open Godot 4 and create a new project.
• Set up the project structure by creating folders for scenes, scripts, and assets.
• Import the required assets:
  • Download the free RPG icon pack for armor and weapons from Clockwork Raven's itch.io page.

Step 2: Creating the Inventory Scene

• Create a new scene and name it Inventory.
• Add a Control node as the root node.
• Inside the Control node, add a GridContainer to manage the item slots.
• Set the GridContainer properties:
  • Column Count: Set the number of columns you need for your inventory.
  • Customizing the size of each slot based on your item dimensions.

Step 3: Designing Item Slots

• Create a new scene for the item slot and name it ItemSlot.
• Add a Control node as the root and include a TextureRect for the item icon.
• Add a Label to display item names.
• Save the ItemSlot scene and instance it in the GridContainer of the Inventory scene.

Step 4: Implementing the Item System

• Create a script for the ItemSlot that handles item data:
  • Define properties such as item_name, item_icon, and item_type.

extends Control

var item_name: String
var item_icon: Texture
var item_type: String

• Add a method to set the item data and update the UI accordingly.

Step 5: Drag-and-Drop Functionality

• Implement drag-and-drop in the ItemSlot script:
  • Use the InputEvent to detect mouse clicks and drags.
  • Allow items to be swapped between slots when dropped.

func _input(event):
    if event is InputEventMouseButton and event.is_pressed():
        # Start drag operation
    elif event is InputEventMouseMotion:
        # Handle dragging visual

Step 6: Managing Inventory Data

• Create a JSON database to store item information.
• Load the database in your main inventory script.

var inventory_data = load_json("res://path_to_your_json_file.json")

• Populate the inventory slots using the loaded data.

Step 7: Connecting the UI and Logic

• Create a UI script that handles inventory interactions.
• Connect the inventory UI with the item system to handle item pickups, drops, and updates.

Conclusion

You have now set up a grid-based inventory system in Godot 4, complete with drag-and-drop functionality and a structured item management system. As next steps, consider enhancing the inventory with features such as item sorting or categorization. You can also explore further customization of UI elements and additional item properties. Happy developing!