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Diffstat (limited to 'gdscript.html.markdown')
| -rw-r--r-- | gdscript.html.markdown | 123 |
1 files changed, 84 insertions, 39 deletions
diff --git a/gdscript.html.markdown b/gdscript.html.markdown index 3312e2e3..ffc08b14 100644 --- a/gdscript.html.markdown +++ b/gdscript.html.markdown @@ -2,13 +2,14 @@ language: GDScript contributors: - ["Wichamir", "https://github.com/Wichamir/"] + - ["zacryol", "https://github.com/zacryol"] filename: learngdscript.gd --- -GDScript is a dynamically typed scripting language made specifically for -free and open source game engine Godot. GDScript's syntax is similar to -Python's. Its main advantages are ease of use and tight integration with -the engine. It's a perfect fit for game development. +GDScript is a dynamically and statically typed scripting language +for the free and open source game engine Godot. Its syntax is vaguely +similar to Python's. Its main advantages are ease of use and tight +integration with the engine. It's a perfect fit for game development. ## Basics @@ -20,9 +21,16 @@ the engine. It's a perfect fit for game development. are written using - docstrings. + triple + quoted + strings """ +# Doc Comments can add a decription to classes and fields +# which can be viewed in the in-engine docs. + +## This class is a demonstration of GDScript + # Script file is a class in itself and you can optionally define a name for it. class_name MyClass @@ -41,8 +49,13 @@ var d = { "key" : "value", 42 : true } # Dictionary holds key-value pairs. -var p_arr = PoolStringArray(["Hi", "there", "!"]) # Pool arrays can - # only hold a certain type. +var p_arr = PackedStringArray(["Hi", "there", "!"]) # Packed Arrays can + # only hold a certain type. + +# Doc comments can apply to properties + +## How many times this object has jumped +var jump_count = 0 # Built-in vector types: var v2 = Vector2(1, 2) @@ -57,10 +70,15 @@ enum { ZERO, ONE , TWO, THREE } enum NamedEnum { ONE = 1, TWO, THREE } # Exported variables are visible in the inspector. -export(int) var age -export(float) var height -export var person_name = "Bob" # Export type hints are unnecessary - # if you set a default value. +# +# Either a type hint (explained later) or a default value are needed in order +# for the editor to know what options to give +@export var age: int +@export var height: float +@export var person_name = "Bob" +# But both is also acceptable +@export var favorite_color: String = "Green" +@export var favorite_food := "Pizza" # Functions func foo(): @@ -69,6 +87,12 @@ func foo(): func add(first, second): return first + second +# Doc Comments on functions + +## Increases the Jump Count +func jump(): + jump_count += 1 + # Printing values func printing(): print("GDScript ", "is ", " awesome.") @@ -76,6 +100,11 @@ func printing(): printt("These", "words", "are", "divided", "by", "tabs.") printraw("This gets printed to system console.") + # Lambdas + var my_lambda = func(): print("hello from lambda!") + + my_lambda.call() + # Math func doing_math(): var first = 8 @@ -97,14 +126,14 @@ func control_flow(): y = 2 # y was originally a float, # but we can change its type to int # using the power of dynamic typing! - + if x < y: print("x is smaller than y") elif x > y: print("x is bigger than y") else: print("x and y are equal") - + var a = true var b = false var c = false @@ -119,7 +148,7 @@ func control_flow(): for i in ["two", 3, 1.0]: # iterating over an array print(i) - + while x > y: printt(x, y) y += 1 @@ -147,7 +176,7 @@ func control_flow(): continue _: print("Underscore is a default case.") - + # ternary operator (one line if-else statement) prints("x is", "positive" if x >= 0 else "negative") @@ -191,7 +220,7 @@ func _physics_process(delta): # like here: func get_children(): # Do some additional things here. - var r = .get_children() # call parent's implementation + var r = super() # call parent's implementation return r # Inner class @@ -220,19 +249,19 @@ func _ready() -> void: # Create NodePath by passing String to its constructor: var path1 = NodePath("path/to/something") # Or by using NodePath literal: - var path2 = @"path/to/something" + var path2 = ^"path/to/something" # NodePath examples: - var path3 = @"Sprite" # relative path, immediate child of the current node - var path4 = @"Timers/Firerate" # relative path, child of the child - var path5 = @".." # current node's parent - var path6 = @"../Enemy" # current node's sibling - var path7 = @"/root" # absolute path, equivalent to get_tree().get_root() - var path8 = @"/root/Main/Player/Sprite" # absolute path to Player's Sprite - var path9 = @"Timers/Firerate:wait_time" # accessing properties - var path10 = @"Player:position:x" # accessing subproperties + var path3 = ^"Sprite" # relative path, immediate child of the current node + var path4 = ^"Timers/Firerate" # relative path, child of the child + var path5 = ^".." # current node's parent + var path6 = ^"../Enemy" # current node's sibling + var path7 = ^"/root" # absolute path, equivalent to get_tree().get_root() + var path8 = ^"/root/Main/Player/Sprite" # absolute path to Player's Sprite + var path9 = ^"Timers/Firerate:wait_time" # accessing properties + var path10 = ^"Player:position:x" # accessing subproperties # Finally, to get a reference use one of these: - sprite = get_node(@"Sprite") as Sprite # always cast to the type you expect + sprite = get_node(^"Sprite") as Sprite # always cast to the type you expect sprite = get_node("Sprite") as Sprite # here String gets # implicitly casted to NodePath sprite = get_node(path3) as Sprite @@ -243,14 +272,17 @@ func _process(delta): # Now we can reuse the reference in other places. prints("Sprite has global_position of", sprite.global_position) -# Use onready keyword to assign a value to +# Use @onready annotation to assign a value to # a variable just before _ready executes. # This is a commonly used syntax sugar. -onready var tween = $Tween as Tween +@onready var other_sprite = $Sprite as Sprite # You can export NodePath, so you can assign it within the inspector. -export var nodepath = @"" -onready var reference = get_node(nodepath) as Node +@export var nodepath = ^"" +@onready var reference = get_node(nodepath) as Node + +# Or export Node directly +@export var other_reference: Node ``` ## Signals @@ -263,27 +295,34 @@ class_name Player extends Node2D var hp = 10 +# Doc comments can go on signals too + +## Emitted when the player dies signal died() # define signal signal hurt(hp_old, hp_new) # signals can take arguments func apply_damage(dmg): var hp_old = hp hp -= dmg - emit_signal("hurt", hp_old, hp) # emit signal and pass arguments + hurt.emit(hp_old, hp) # emit signal and pass arguments if hp <= 0: - emit_signal("died") + died.emit() func _ready(): # connect signal "died" to function "_on_death" defined in self - self.connect("died", self, "_on_death") + died.connect(_on_death) + # Alternate way + # needed if the target object is not self + # died.connect(Callable(self, &"_on_death")) func _on_death(): - self.queue_free() # destroy Player on death + queue_free() # destroy Player on death ``` ## Type hints -GDScript can optionally use static typing. +GDScript can optionally use static typing, for both code clarity and +performance benefits. ```gdscript extends Node @@ -292,15 +331,23 @@ var x: int # define typed variable var y: float = 4.2 var z := 1.0 # infer type based on default value using := operator -onready var node_ref_typed := $Child as Node +var a: Array[int] = [1, 2, 3] # Array can also have its type content specified -export var speed := 50.0 +enum NamedEnum { ONE = 1, TWO, THREE } +var n: NamedEnum = NamedEnum.ONE # Enums can be used as types as well + +@onready var node_ref_typed := $Child as Node + +@export var speed := 50.0 const CONSTANT := "Typed constant." +signal example(arg: int) + func _ready() -> void: # function returns nothing x = "string" # ERROR! Type can't be changed! + a.append("q") # ERROR! Array[int] can't hold strings! return func join(arg1: String, arg2: String) -> String: @@ -310,8 +357,6 @@ func join(arg1: String, arg2: String) -> String: func get_child_at(index: int) -> Node: # function takes an int and returns a Node return get_children()[index] - -signal example(arg: int) # ERROR! Signals can't take typed arguments! ``` ## Further Reading |