Tween with float property will be forced to interpolate as int type when passing int to Tween's argument

[saierXP]

Tested versions

4.2.1

System information

windows10

Issue description

extends Node2D

func _ready() -> void:
	var t := create_tween()
	t.set_parallel()
	t.tween_property($Icon1,'rotation', PI, 1).from(0) # row1 left
	t.tween_property($Icon2,'rotation', PI, 1).from(0.0) # row1 right
	t.tween_property($Icon3,'rotation', PI, 1).as_relative().from(0) # row2 left
	t.tween_property($Icon4,'rotation', PI, 1).as_relative().from(0.0) # row2 right

tween interpolates by the type of the from argument, not the float type of the property.
Does not work if as_relative is used.

Steps to reproduce

Run the MRP project attached below.

Minimal reproduction project (MRP)

tween-int.zip

[jsjtxietian]

Related to #73178 and #74112

Reading the code, it seems godot does use the from value to determine final value.
But the final value is validated by the property value type in tween_property already, IMHO it should validate the from value by the final value instead of doing the opposite.

cc @KoBeWi

[KoBeWi]

I'm getting a different result in 4.3 dev2:

xXrqr0kLWU.mp4

Seems like this was fixed by some of the animation changes.

Can you confirm the issue is fixed for you in the newest version?

[saierXP]

Can you confirm the issue is fixed for you in the newest version?

The as_relative().from(0) one was fixed, but from(0) wasn't.

[TokageItLab]

Fixed by #86046

but from(0) wasn't.

Not sure what you are referring to, but if you mix Int and float, the float will take precedence to make subsequent transitions consistent. This is an intended behavior.

If you have any other problems, please check the latest master or 4.3.dev2 or later versions and report them if you still have problems.

[kleonc]

but from(0) wasn't.

Not sure what you are referring to, but if you mix Int and float, the float will take precedence to make subsequent transitions consistent. This is an intended behavior.

If you have any other problems, please check the latest master or 4.3.dev2 or later versions and report them if you still have problems.

See how the t.tween_property($Icon1,'rotation', PI, 1).from(0) # row1 left behaves (top-left in the examples above).

Calling .from(0) makes the tweener tween with integers even though both the property and the final value passed are floats. So it's not true that float always take precendence in case of mixing float/int.

To me it seems like unintended behavior / bug.

---

Specifically when calling from(an_int) both initial_val and final_val end up being ints:

godot/scene/animation/tween.cpp

Lines 506 to 512 in 0bcc0e9

	Ref<PropertyTweener> PropertyTweener::from(const Variant &p_value) {
	ERR_FAIL_COND_V(tween.is_null(), nullptr);
	if (!tween->_validate_type_match(p_value, final_val)) {
	return nullptr;
	}
	initial_val = p_value;

godot/scene/animation/tween.cpp

Lines 73 to 74 in 0bcc0e9

	} else if (p_from.get_type() == Variant::INT && r_to.get_type() == Variant::FLOAT) {
	r_to = int(r_to);

Hence delta_val etc. is int:

godot/scene/animation/tween.cpp

Line 564 in 0bcc0e9

delta_val = Animation::subtract_variant(final_val, initial_val);