A drag 'n drop Godot 3 example

README.md

This is a drag 'n drop Godot 3 example.

Example

You found 4 pieces of paper and now you have to arrange them in order to read the message on it.

Instructions

1. Add a scene with a Node2D element.
2. Connect ShapeMinigame.gd script to it.
3. Add multiple KinematicBody2D elements with a Rectangular CollisionShape2D and, if you want, a Sprite.
4. Connect DragElement.gd script to it.
5. Set targetPosition per KinematicBody2D element.
6. Create a SuccessLabel, which will be shown as soon as all elements have reached target position.
7. Have fun!

DragElement.gd

extends KinematicBody2D

signal has_reached_target_position

export var targetPosition = Vector2(-1, -1)

var isDragging: bool = false
var hasReachedTargetPosition: bool = false


func _ready() -> void:
    add_to_group("Draggables")
    input_pickable = true


func _process(_delta) -> void:
    if hasReachedTargetPosition: return

    if isDragging:
        z_index = 2 # So draggable element is always on top
        position = get_viewport().get_mouse_position()
    else:
        z_index = 0


func _on_input_event(_viewport, event, _shape_idx) -> void:
    if hasReachedTargetPosition: return

    if event is InputEventMouseButton:
        if event.button_index == BUTTON_LEFT and event.pressed:
            isDragging = true
        elif event.button_index == BUTTON_LEFT and not event.pressed:
            _on_drag_end()
    elif event is InputEventScreenTouch:
        if event.pressed and event.get_index() == 0:
            position = event.get_position()


func _on_drag_end() -> void:
    isDragging = false

    # Check if target position was reached
    if position.ceil() == targetPosition:
        _on_target_position_reached()


func _on_target_position_reached() -> void:
    hasReachedTargetPosition = true
    emit_signal('has_reached_target_position')
    z_index = 0

ShapeMinigame.gd

extends Node2D

var dragElements = []
var numDragElementsHaveReachedTargetPosition = 0


func _ready() -> void:
    dragElements = get_tree().get_nodes_in_group("Draggables")

    for node in dragElements:
        node.connect("has_reached_target_position", self, "_on_element_has_reached_target_position")


func _on_element_has_reached_target_position() -> void:
    numDragElementsHaveReachedTargetPosition += 1

    if numDragElementsHaveReachedTargetPosition == dragElements.size():
        $SuccessLabel.show()