godot-gdscript

name	godot-gdscript
description	Godot game development — GDScript/C# patterns, scene system, signals, and Godot 4 best practices
allowed-tools	["Read","Write","Bash","Grep"]
effort	medium

When to activate

• Building games with Godot 4 engine
• Designing scene trees and node compositions
• Using GDScript or C# for game logic
• Implementing Godot's signal-based event system
• Working with Godot's built-in editor and export pipeline

When NOT to use

• For Unity or Unreal development
• For non-game Godot applications
• For Godot 3.x (API has changed significantly)

Instructions

1. Scene system. Scenes are node trees. Compose complex scenes from smaller scenes. Use PackedScene.instantiate().
2. Node patterns. @onready for cached nodes. _ready() for init. _process() for per-frame, _physics_process() for fixed-rate.
3. Signals. Decouple with signals: signal health_changed(new_value). Connect in editor or code. Use await for signal sequences.
4. Export variables. @export var speed: float = 200.0 for editor-editable. @export_range, @export_enum for constraints.
5. State machines. Use child nodes as states. TransitionTo("running") pattern. Consider LimboHSM plugin for complex FSMs.
6. Performance. Object pooling with @onready var pool: Array. Avoid _process on inactive objects. Use call_deferred for expensive ops.
7. Export. Configure export presets per platform. Use Export Debug to catch issues. Test on target hardware regularly.

Example

# Character controller with state machine
extends CharacterBody2D

@export var speed: float = 200.0
@export var jump_force: float = -400.0
@export var gravity: float = 980.0

@onready var anim_player: AnimationPlayer = $AnimationPlayer

signal state_changed(new_state: String)

func _physics_process(delta: float) -> void:
    # Apply gravity
    if not is_on_floor():
        velocity.y += gravity * delta
    
    # Handle jump
    if Input.is_action_just_pressed("jump") and is_on_floor():
        velocity.y = jump_force
    
    # Horizontal movement
    var direction = Input.get_axis("move_left", "move_right")
    velocity.x = direction * speed
    
    move_and_slide()