Game Maker to Godot dictionary

This document is for game maker devs like me that are moving their games or engine from GM:S to Godot. You can you your browser's search functionality to find GML functions and their equivalent in GDScript.

Index

Events
Scripts
Globals
Drawing functions
Instance functions
Strings
Random functions
Game functions
Window functions

Events

On Game Maker when you need to code logic inside an object you use Events. There are many kinds of events but the most used ones are: create, step, draw.

Create Event

When you need to declare variables for an object in GMS you do it inside the Create Event. The equivalent in Godot is a function called _ready(). The main difference here is that on GMS, the Create Event declares variables that are accesible from everywhere. In Godot if you want your variables to be exposed to other functions or Nodes (objects) you need to declare them outside of the _ready() function at the top of the document.

Imagine that we want to set the variable player_speed to 10 but if there are monsters present, you want it to be 5. In Game Maker you can code all this inside the Create Event:

GML Create Event

player_speed = 10;
monsters = instance_number(obj_monster);

if (monsters) {
    player_speed = 5;
}

In Godot you will have to code it like this:

GDScript _ready()

extends Node

var player_speed = 10

func _ready():
    var monsters = get_tree().get_nodes_in_group("MONSTERS").size();
    if monsters:
        player_speed = 5

Step Event

Simple Step Event function for moving an object.

GML Step Event

x += player_speed;

GDScript _process()

func _process(delta):
    position.x += player_speed

Draw Event

Simple Step Event function for moving an object.

GML Draw Event

draw_rectangle(100, 120, 132, 152, false);

GDScript _draw()

func _draw():
    draw_rect(Rect2, Color, bool filled=true)

Destroy event

There is not an equivalent event for the Destroy Event but it can easily be coded in GDScript. Instead of destroying that node with the usual queue_free() you create a function called destroy() and execute some code before self deleting.

GDScript destroy()

func destroy():
    # Here you write whatever you want to 
    # run before removing the node
    self.queue_free()

Scripts

In game maker you can create scripts that you can call from any object in your project. In Godot, the so called "scripts" are called functions and you can declare all the custom functions that you want inside any node.

To compare between the two you can see this simple "script" that will add two numbers:

GML: Create new script called add_numbers

return argument0 + argument1;

GDScript: Inside a node's code

func add_numbers(argument0, argument1):
    return argument0 + argument1

In Godot instead of using the names argumentX it is recommended that you use a more descriptive name. Every argument named when you declare the function will create a variable that you can use from inside of it.

func add_numbers(number_one, number_two):
    return number_one + number_two

Globals

In Game Maker you can declare globals very easy by just adding global. at the start of a variable. In Godot you can create a similar kind of variables via the Singletons (AutoLoad) feature.

I recommend you to read the entry of the Godot documentation but to get a quick equivalent you can do the following:

First of all, create a global.gd script.
Then, Select Project > Project Settings from the menu, switch to the AutoLoad tab
Add a new entry with name “global” that points to this file:

Now, whenever you run any of your scenes, the script is always loaded. The variables declared inside global.gd can be accesed or modified the same way you would do in GML: global.variable_name.

The cool thing about godot is that you can also declare functions inside the global.gd file that you can use from any other instance inside your game.

Drawing functions

On game maker you can only use the drawing functions inside the draw event of an instance. On Godot you have to call the drawing functions inside a func _draw() of a CanvasItem.

Making colors

GML

// These values are taken as being between 0 and 255
make_colour_rgb(red, green, blue);

And you also have the colors like c_white, c_blue, etc..

GDScript

# Constructs a color from an RGB profile using values between 0 and 1 (float)
Color(0.2, 1.0, .7)
# You can also set the color alpha by adding an aditional value
Color(0.2, 1.0, .7, 0.5)

You can also create a color from standardised color names with ColorN. See the full list here.

Drawing a rectangle

GML

draw_rectangle(x1, y1, x2, y2, outline);

GDScript

draw_rect(Rect2, Color, bool filled=true)

Example:

To draw the same rectangle on both engines:

GML

draw_set_color(c_red);
draw_rectangle(100, 120, 132, 152, false);

GDScript

draw_rect(Rect2(Vector2(100, 120), Vector2(32, 32)), ColorN("red"), true)

Drawing text

Drawing text is a bit more tricky in Godot. Make sure you declare the font resource outside of the _draw() function.

GML

draw_text(x, y, string);

GDScript

draw_string(font,Vector2(x,y),string,color,separation)

Example:

To draw the same rectangle on both engines:

GML

draw_set_font(fn_bitter);
draw_set_font(make_color_rgb(0,0,0));
draw_text(140, 100, "Hello world");

GDScript

var font = load('res://fonts/Bitter.tres')
func _draw():
	draw_string(Bitter,Vector2(140,100),"Hello world", Color(0,0,0,1),-1)

Visibility

GML

visible = true;
visible = false;

GDScript

self.show()
self.hide()

Instance functions

Instance destroy

GML

instance_destroy();

GDScript

self.queue_free()

Strings

String functions are a little bit different because in game maker everything is a function but in Godot they are methods. You can also treat Strings in godot like arrays.

String Length

GML

string_length(string);

GDScript

string.length

String Char At

GML

string_char_at(string, index);

GDScript

string[index]

String Upper/Lower

GML

string_upper(string);
string_lower(string);

GDScript

string.to_upper()
string.to_lower()

String Delete

GML

string_delete(string, index, count);

GDScript

string.erase(index, count)

Random functions

Choose

GML

var value = choose(1, 2, 3);

In order to achieve something similar in Godot you have to first create an array with all the options and then get a random value from that array.

GDScript

var options = [1, 2, 3]
var value = options[randi() % options.size()])

Game functions

Game end

With this function you can quit the game.

GML

game_end();

GDScript

get_tree().quit()

Window functions

Set caption

GML

window_set_caption(string);

GDScript

OS.set_window_title(string)

Sources

Game Maker docs
Godot documentation

< Written by Emilio Coppola >

Special thanks to a lot of poor souls that helped me answering questions on Discord, Reddit and Twitter.

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

readme.md

readme.md

Game Maker to Godot dictionary

Index

Events

Create Event

Step Event

Draw Event

Destroy event

Scripts

Globals

Drawing functions

Making colors

Drawing a rectangle

Example:

Drawing text

Example:

Visibility

Instance functions

Instance destroy

Strings

String Length

String Char At

String Upper/Lower

String Delete

Random functions

Choose

Game functions

Game end

Window functions

Set caption

Sources

< Written by Emilio Coppola >

Files

readme.md

Latest commit

History

readme.md

File metadata and controls

Game Maker to Godot dictionary

Index

Events

Create Event

Step Event

Draw Event

Destroy event

Scripts

Globals

Drawing functions

Making colors

Drawing a rectangle

Example:

Drawing text

Example:

Visibility

Instance functions

Instance destroy

Strings

String Length

String Char At

String Upper/Lower

String Delete

Random functions

Choose

Game functions

Game end

Window functions

Set caption

Sources

< Written by Emilio Coppola >