I'm trying to make a bird that follows a Position2D node attached to the character.(The Position2D node is in group called birdpos) When I run the game as soon as the bird is on screen (screendetector) it goes to the Position2D node. However once it reaches its destination it gives me the error "Invalid get index '1' (on base: 'Array')." (im also getting jittering when it reaches position) Im sure this is an easy fix, here is my code
extends KinematicBody2D
export(int) var SPEED: int = 100
var velocity: Vector2 = Vector2.ZERO
var path: Array = []
var levelNavigation: Navigation2D = null
var birdpos = null
onready var line2d = $Line2D #shows pathing
func _ready():
var tree = get_tree()
$flyingsprite1/AnimationPlayer.play("flying")
if tree.has_group("LevelNavigation"):
levelNavigation = tree.get_nodes_in_group("LevelNavigation")[0]
func move():
velocity = move_and_slide(velocity)
func _on_screenchecker_area_entered(area):
$Timer.start()
print("ligma")
yield(get_tree(), "idle_frame")
var tree = get_tree()
if tree.has_group("LevelNavigation"): #navigation node
levelNavigation = tree.get_nodes_in_group("LevelNavigation")[0]
if tree.has_group("birdpos"): #Position2D that is attached to player
birdpos = tree.get_nodes_in_group("birdpos")[0]
func _on_screenchecker_area_exited(area):
print("liga")
$Timer.stop()
var birdpos = null
var levelNavigation: Navigation2D = null
func _on_Timer_timeout():
line2d.global_position = Vector2.ZERO
if birdpos and levelNavigation:
generate_path()
func _physics_process(delta):
if Global.player.facing_right == true:
$flyingsprite1.scale.x = -1
else:
$flyingsprite1.scale.x = 1
if birdpos and levelNavigation:
navigate()
move()
func generate_path():
if levelNavigation != null and birdpos != null:
path = levelNavigation.get_simple_path(global_position, birdpos.global_position, false)
line2d.points = path
func navigate():
if path.size() > 0:
velocity = global_position.direction_to(path[1]) * SPEED
if global_position == path[0]:
path.pop_front()
edit: Updated Code
extends KinematicBody2D
export(int) var SPEED: int = 200
var velocity: Vector2 = Vector2.ZERO
var path: Array = []
var levelNavigation: Navigation2D = null
var birdpos = null
onready var line2d = $Line2D
func _ready():
# speed is distance over time
var tree = get_tree()
$flyingsprite1/AnimationPlayer.play("flying")
#if tree.has_group("Player"):
#player = tree.get_nodes_in_group("Player")[0]
func _on_screenchecker_area_exited(area):
$Timer.stop()
var birdpos = null
var levelNavigation: Navigation2D = null
func _on_Timer_timeout():
line2d.global_position = Vector2.ZERO
if birdpos and levelNavigation:
generate_path()
func _physics_process(delta):
if path.size() == 0:
return
var levelNavigation: Navigation2D = null
var birdpos = null
var next := global_position.move_toward(path[0], SPEED * delta)
var displacement := next - global_position
# And divide by it delta to get velocity:
move_and_slide(displacement/delta)
if Global.player.facing_right == true:
$flyingsprite1.scale.x = -1
else:
$flyingsprite1.scale.x = 1
if birdpos and levelNavigation:
navigate()
move()
func _input(event):
if Input.is_key_pressed(KEY_Q):
var tree = get_tree()
func _on_screenchecker_area_entered(area):
$Timer.start()
yield(get_tree(), "idle_frame")
var tree = get_tree()
if tree.has_group("LevelNavigation"):
levelNavigation = tree.get_nodes_in_group("LevelNavigation")[0]
if tree.has_group("birdpos"):
birdpos = tree.get_nodes_in_group("birdpos")[0]
func generate_path():
if levelNavigation != null and birdpos != null:
if is_instance_valid(birdpos):
path = levelNavigation.get_simple_path(global_position, birdpos.global_position, false)
line2d.points = path
func navigate():
if path.size() > 1:
velocity = global_position.direction_to(path[1]) * SPEED
if path.size() == 0:
path.pop_front()
func move():
if path.size() == 0:
return
velocity = move_and_slide(velocity)
The error
In this code:
if path.size() > 0:
velocity = global_position.direction_to(path[1]) * SPEED
if global_position == path[0]:
path.pop_front()
You check if the path has more than 0 points with path.size() > 0. That is, you are checking if the path has at least 1 point.
But to access path[1], the path must have at least 2 points.
Thus, if the path has exactly 1 point, it will pass the check path.size() > 0 and fail when reading path[1].
I don't know when the path would have exactly one point. It is not documented how this could happen, and it could be a problem with the navigation, it could even be a bug in Godot. But, as far as I can tell it is happening for you.
Presumably you want to reach path[0] instead of path[1] since that is what you are checking against to remove points.
If you do in fact want path[1], then check if the path has at least 2 points with path.size() > 1 (or path.size() >= 2 if you prefer).
The jitter
I'm assuming here that path[0] is the target.
I believe it is three things:
You cannot trust vector equality
Vector equality boils down to equality of the components. Which is float equality. And thus Vector equality has all the problems of float equality.
So, to compare to your current target use is_equal_approx. For example global_position.is_equal_approx(path[0]).
You don't want to move if you reached the target
This is easy enough: If there are no more points in path, don't move. That is, you can add this at the start of move:
if path.size() == 0:
return
If you will have the code in _physics_process instead of move, remember to check there.
You don't want to overshoot
So, move_and_slide will move the object as much as it should given the time between physics frames (delta). But that might be more than necessary to reach the target. As consequence, it is very likely to overshoot the target. As a result, the next physics frame it will have to move in the opposite direction, and overshoot again, and so on… Jitter!
I'll give you three solutions:
Don't use move_and_slide (with the caveat that you would be forgoing physics collisions):
# you can use move_toward
global_position = global_position.move_toward(path[0], SPEED * delta)
Let us keep move_and_slide, but compute the displacement we want.
# you can use move_toward
var next := global_position.move_toward(path[0], SPEED * delta)
# Then compute the displacement
var displacement := next - global_position
# And divide by it delta to get velocity:
move_and_slide(displacement/delta)
Again, using move_and_slide, but this time we figure out the maximum speed to not overshoot:
# speed is distance over time
var max_speed := global_position.distance_to(path[0])/delta
# And we clamp!
move_and_slide(velocity.clamped(max_speed))
For the versions of the code that use delta you can either put the code in _physics_process, or pass delta to move as a parameter. Also don't forget the check for path.size() mentioned in the prior point.
Addendum If you use path[0] as target, but it was equal to the current position, you would get about no velocity, and have to waste a physics frame. Consider this rewrite:
if path.size() > 0 and global_position.is_equal_approx(path[0]):
path.pop_front()
if path.size() > 0:
velocity = global_position.direction_to(path[0]) * SPEED
Related
I have a game I'm making in Godot, 2D
I have a progres sbar called "Healthbar"
I'm trying to set it's value to the players HP value
the full code is as follows
extends KinematicBody2D
var health: float = 100
func ready():
pass
export var movespeed : int
export var batteryspeed: int
var battery = preload("res://Bullet.tscn")
func _physics_process(delta):
get_tree().get_root().find_node("HealthBar").value = health
var motion = Vector2()
if (health <= 0):
gameover()
if(Input.is_action_pressed("MoveUp")):
motion.y -= 1
if(Input.is_action_pressed("MoveLeft")):
motion.x -= 1
if(Input.is_action_pressed("MoveDown")):
motion.y += 1
if(Input.is_action_pressed("MoveRight")):
motion.x += 1
motion = motion.normalized()
motion = move_and_slide(motion * movespeed)
if(Input.is_action_just_pressed("Fire")):
fire()
look_at(get_global_mouse_position())
func fire():
var batteryInstance = battery.instance()
batteryInstance.position = position
batteryInstance.rotation_degrees = rotation_degrees
batteryInstance.apply_impulse(Vector2(), Vector2(batteryspeed, 0).rotated(rotation))
get_tree().get_root().call_deferred("add_child", batteryInstance)
func gameover():
get_tree().reload_current_scene()
func _on_Area2D_body_entered(body):
if "Enemy" in body.name:
health -= 10
and the part I'm having issues with, I suspect is
get_tree().get_root().find_node("HealthBar").value = health
What do I do to set the progressbar value to the health variable?
It turns out you must use the function
{Progress Bar}.set_value({value})
I found this code to push a rigidbody with a kinematic body in godot:
for index in get_slide_count():
var collision = get_slide_collision(index)
if collision.collider.is_in_group("bodies"):
collision.collider.apply_central_impulse(-collision.normal * push)
This code works but when the player stand on rigidbody can't jump!!
P.S. I have set the infinite_inertia to false. All code is this:
extends KinematicBody2D
onready var animation = $AnimationPlayer
export (int, 0, 200) var push = 30
var velocity :=Vector2.ZERO
var gravity := 30
var speed := 50
var jumpforce = 300
func _physics_process(delta) -> void:
#Push()
if Input.is_action_pressed("right"):
$Sprite.flip_h=false
velocity.x += speed
animation.play("Walk")
elif Input.is_action_pressed("left"):
$Sprite.flip_h=true
velocity.x -= speed
animation.play("Walk")
else:
animation.play("Idle")
if Input.is_action_just_pressed("jump") and is_on_floor():
velocity.y =- jumpforce
animation.play("Idle")
velocity.y += gravity
Push()
velocity=move_and_slide(velocity,Vector2.UP, false, 4, PI/4, false)
velocity.x= lerp(velocity.x,0,0.2)
func Push():
for index in get_slide_count():
var collision = get_slide_collision(index)
if collision.collider.is_in_group("bodies"):
collision.collider.apply_central_impulse(-collision.normal * push)
I found the solution to this problem!!! I set the rigitbody 's mass property from editor to 2 instead 1 . Is working now :)
I'm trying to game a game using the Godot Engine but I'm stuck at the beginning! I can't make my KinematicBody2D move!
This is my Player.GD script
extends KinematicBody2D
var velocity = Vector2.ZERO
var move_speed = 480
var gravity = 1200
var jump_force = -720
var right = Input.is_action_pressed("move_right")
var left = Input.is_action_pressed("move_left")
var jump = Input.is_action_pressed("jump")
func _ready():
pass
func _physics_process(_delta):
var move_direction = int(right) - int(left)
velocity.x = move_speed * move_direction
move_and_collide(velocity)
Can someone, please, help me?
All this code will run when the KinematicBody2D is initialized:
var velocity = Vector2.ZERO
var move_speed = 480
var gravity = 1200
var jump_force = -720
var right = Input.is_action_pressed("move_right")
var left = Input.is_action_pressed("move_left")
var jump = Input.is_action_pressed("jump")
In consequence, it will not be taking input in real time. Instead you want the last three lines here:
func _physics_process(_delta):
var right = Input.is_action_pressed("move_right")
var left = Input.is_action_pressed("move_left")
var jump = Input.is_action_pressed("jump")
# …
Those are boolean, by the way. You can get a float from 0.0 to 1.0 if you use Input.get_action_strength instead. Which will also let your code ready for analog input.
I also want to point out that move_and_collide does not take a velocity, but a displacement vector. So to call it correctly, you want to multiply the velocity by delta:
func _physics_process(delta):
# …
move_and_collide(velocity * delta)
Or use move_and_slide, which does take a velocity. By the way, the up parameter that move_and_slide takes is to discern between floor, ceiling, and walls. Without, everything is considered a wall.
I'm trying to make a 2d platformer where you spawn an object and try to jump on it in the air before it falls.
the problem is when I try to spawn the tile it doesn't spawn where Is the cursor at
it adds a relative value to the position that I don't know how to get rid of it.
you see when I try to instance a scene it takes the cursor position and viewport value into account but then something happens and I fount the object spawning way too far.
see where is the cursor at and where did the tile spawn
, same thing here
, and here
-here is how I'm grouping the nodes and scenes-
and this is the script I'm using, it's in the player1 scene
extends KinematicBody2D
#
var score : int = 0
export var speed : int = 200
export var jumpforce : int = 600
export var gravity : int = 800
onready var AB1 = preload("res://player1AB.tscn")
var vel :Vector2 = Vector2()
onready var sprite : Sprite = get_node("sprite_idile")
onready var ui : Node = get_node("/root/mainscene1/CanvasLayer/ui")
onready var audioplayer : Node = get_node("/root/mainscene1/Camera2D/audio_player")
func _physics_process(delta):
vel.x = 0
# movement inputs
if Input.is_action_pressed("move_left"):
vel.x -= speed
if Input.is_action_pressed("move_right"):
vel.x += speed
# applying the velcoty
vel = move_and_slide(vel,Vector2.UP)
#apllying gravty
vel.y += gravity * delta
#jump input
if Input.is_action_just_pressed("jump") and is_on_floor():
vel.y -= jumpforce
# where the sprite facing
if vel.x < 0:
sprite.flip_h = true
if vel.x > 0:
sprite.flip_h = false
if Input.is_action_just_pressed("restart"):
death()
func death ():
get_tree().reload_current_scene()
func collect_coin (value):
score += value
ui.set_score_text(score)
audioplayer.play_coin_sfx()
func _input(event):
if event.is_action_pressed("click"):
var ABT1 = AB1.instance()
add_child(ABT1)
var XN = null
XN = get_viewport().get_mouse_position()
ABT1.position = XN
important stuff
onready var AB1 = preload("res://player1AB.tscn")
func _input(event):
if event.is_action_pressed("click"):
var ABT1 = AB1.instance()
add_child(ABT1)
var XN = null
XN = get_viewport().get_mouse_position()
ABT1.position = XN
this the same problem in Godot form check it out if possible in case someone answered there
https://godotforums.org/discussion/27007/my-get-viewport-get-mouse-position-isnt-working-right#latest
If you don't have an extra Viewport
My first intuition is to get get_global_mouse_position and set global_position. That way you don't have to deal with any relative positioning:
ABT1.global_position = get_global_mouse_position()
Alternatively, you can check if the event is InputEventMouse, make it local with make_input_local, and get InputEventMouse.position from it:
func _input(event):
if event is InputEventMouse and event.is_action_pressed("click"):
var ABT1 = AB1.instance()
add_child(ABT1)
event = make_input_local(event)
ABT1.position = event.position
This approach would make it easier to then add touch support, because it does not rely on any function that gives you the mouse position. See my answer for Holding screen touch in godot.
If you have an extra Viewport
First of all, make sure you put your Viewport inside a ViewportContainer (otherwise it does not get input, see _input not called for a node inside a Viewport). Then we can use that ViewportContainer to get our coordinates.
Something like this:
func _input(event):
if event is InputEventMouse and event.is_action_pressed("click"):
var ABT1 = AB1.instance()
add_child(ABT1)
var container = find_parent("ViewportContainer") as ViewportContainer
if container != null:
event = container.make_input_local(event)
event = make_input_local(event)
ABT1.position = event.position
Notice there I'm using the function find_parent. It matches by name of the Node, not by type. Another approach you can try is using get_viewport().get_parent().
And yes, that should work regardless of stretch mode.
Rewritten and Edited for clarity. Assume that I have a 2d platformer like the following example:
https://github.com/godotengine/godot-demo-projects/blob/master/2d/kinematic_character/player.gd
Now... Say I have the player location (vector2) and the enemy location (vector2). The enemy movement works just like the player in the above example. I use get_simple_path to build an array of pre-existing points that lead from the enemy location to the player location. How do I use that array with move_and_slide to get the enemy from point A to point B?
You could try the following:
const GRAVITY = 1000
const SLOPE_SLIDE_STOP = false
var speed = 250
var velocity = Vector2()
var points = [Vector2(100, 200), Vector2(200, 400), Vector2(400, 800)]
var current_point = null
func _physics_process(delta):
if points and current_point is null:
current_point = points.pop_front()
if current_point:
if current_point.distance_to(position) > 0:
target_direction = (position - current_point).normalized()
velocity.y += delta * GRAVITY
velocity = lerp(velocity, target_speed, 0.1)
velocity = move_and_slide(velocity, target_direction, SLOPE_SLIDE_STOP)
else:
current_point = null