Topic was automatically imported from the old Question2Answer platform.
Asked By
Benjamin S.
Old Version
Published before Godot 3 was released.
Hey,
i want to increase the value of the rotation from the current rotation value to a certainly value slowly (so that it looks like an animation or so. Here is my code:
set_rot uses radians, you need a tiny value to make a small movement or use rotd in degrees, also you have to add to the previous rotation value. rotate adds to the current rotation.
If rotating during (any) _process, you can use an integrator method to get smooth movement, in short, think on how fast should rotate in a second and multiply by the time between process.
All that means, inside process:
rotate(ammount_in_radians*delta)
or
set_rot(get_rot()+ammount_in_radians*delta)
or
set_rotd(get_rotd()+ammount_in_degrees*delta)
You may need to read about basic motion control in games to understand more what is all about (mostly basic math and physics applied to games).
You want to interpolate the angle. Vectors have an angle_to() method that does the work of having to write a utility function to calculate the difference between two angles.
From there you want to multiply in some amount between 0 and 1 to get yourself a slice of that angle difference. Then add that to the current rotation.
This is done in radians, so be mindful of that, as the other poster pointed out. If you prefer degrees, and don’t have to worry about overhead, then there is the deg2rad() function that can be helpful.
If you’re doing this as a continuous effect, then you will want to pick some turning speed, and maybe adjust it. If you’re doing animation, then you can use tweening and easing algorithms to provide you with a “t” (time) value.
I recently wrote an example for myself to do this for some other application. Maybe you will find this helpful.
extends Node2D
var turning_speed = .04
var orientation = Vector2(0,1)
var line_distance = Vector2(0,0)
var sprite = Sprite.new()
var sprite_pos
func _ready():
var screen_size = get_viewport().get_visible_rect().size
sprite.set_texture(preload("res://icon.png"))
sprite.set_pos(Vector2(screen_size.x / 2, screen_size.y / 2))
sprite_pos = sprite.get_pos()
add_child(sprite)
set_process(true)
func _process(delta):
var m = get_viewport().get_mouse_pos()
m -= sprite_pos
line_distance = m
m = m.reflect(m)
var new_angle = orientation.angle() + orientation.angle_to(m) * turning_speed
orientation.x = sin(new_angle)
orientation.y = cos(new_angle)
sprite.set_rot(orientation.angle())
update()
func _draw():
draw_line(sprite_pos, sprite_pos + line_distance, Color(.01, .2, .6, .8), 2)
