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Attention | Topic was automatically imported from the old Question2Answer platform. |
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Asked By | Boris Šehovac |
Since I couldn’t figure out how to add custom easing functions to existing Tween, I decided to make custom Tween class where I could implement them. Actually the only reason for this is that Tween.TRANS_ELASTIC is not configurable in any way. Anyway, I wanted to check is there any performance drawbacks with this, or did anyone else implemented it in original Tween. I like Godot very much, but it really misses some basic functionalities…
extends Node
class_name TweenCustom
var tween_id = 0
var tween_data = {
'id': 0,
'start': 0,
'duration': 0,
'object': null,
'update': null,
'complete': null,
'easing': null,
}
var tweens = {}
func _ready():
set_process(false)
func _process(delta):
for id in tweens.keys():
update(id)
func update(id):
var now = OS.get_ticks_msec() / 1000.0
var tween = tweens[id]
var delta = now - tween.start
var time = 0.0
if tween.duration != 0.0:
time = delta / tween.duration
else:
time = 1.0
var complete = false
var value = tween.easing.call_func(time, tween.config)
if time >= 1.0:
complete = true
value = 1.0
tween.update.call_func(value)
if complete:
tween.complete.call_func()
tweens.erase(tween.id)
if tweens.size() < 1:
set_process(false)
func start(object = Node, duration = 1.0, easing = LINEAR(), callback = null, complete = null):
var tween = tween_data.duplicate()
tween.id = get_id()
tween.start = OS.get_ticks_msec() / 1000.0
tween.duration = duration
tween.object = object
tween.update = funcref(object, callback)
tween.easing = funcref(self, easing.func)
tween.complete = funcref(object, complete)
tween.config = easing.config
tweens[tween.id] = tween
update(tween.id)
set_process(true)
func get_id():
var id = tween_id
tween_id += 1
return id
func LINEAR():
return { 'func': 'ease_linear', 'config': null }
func ELASTIC_OUT(amplitude = 0.8, period = 0.6):
var PI2 = PI * 2
var p1 = amplitude if amplitude >= 1 else 1
var p2 = period / amplitude if amplitude < 1 else period
var p3 = p2 / PI2 * asin(1/ p1) if p1 != 0 else 0
p2 = PI2 / p2
return { 'func': 'ease_elastic_out', 'config': { 'p1': p1, 'p2': p2, 'p3': p3 } }
func ease_elastic_out(t, c):
return c.p1 * pow(2, -10 * t) * sin((t - c.p3) * c.p2) + 1
func ease_linear(t):
return t
It would be triggered like this:
tween.start(self, 3.0, tween.ELASTIC_OUT(0.8, 0.6), 'on_update', 'on_complete')