Moving my character horizontally slightly affects the linear_velocity().y and I can't understand why?

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:information_source: Attention Topic was automatically imported from the old Question2Answer platform.
:bust_in_silhouette: Asked By Robster
:warning: Old Version Published before Godot 3 was released.

Hi all,

Here is my move:

func move(speed, acc, delta):
	#lerp interpolates smoothly between a source number (first value) and a destination number (Second value) by weight (last value)
	current_speed.x = lerp(current_speed.x , speed, acc * delta)
	set_linear_velocity(Vector2(current_speed.x,get_linear_velocity().y))

When my character moves left and right it does the following:

  • Moving right the VERTICAL (Y) velocity hovers to around - .008
  • Moving left the VERTICAL (Y) velocity hovers to around + .008

This is causing havoc with my jump animation as it uses something like:

if get_linear_velocity().y > 0:
		anim = "fall"
	elif get_linear_velocity().y < 0:
		anim = "jump"

The problem is then:
Whenever I walk right, the fall animation flickers in and out.
Whenever I walk left, the jump animation flickers in and out.

Can anyone see a workaround for this? It’s a real pain and I can’t quite figure out a fix.

NOTE: I’ve checked the ground plane it’s walking on and all rotations are 0. From the static body to the collision shape.

Thanks a tonne… Rob

Maybe the collision shape of your character is a rectangle? Rounded areas slide better on ground than flat ones.

genete | 2016-08-20 06:31

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:bust_in_silhouette: Reply From: ericdl

Just recreated your project as best I could from the snippets you provided, and ran into the y-float problem you described. Was able to solve it by setting the friction property to zero in either the rigidbody2d or static body ground plane.

Thank you ericdl.

I already had friction set to 0 on the character’s RidigBody2D.
I then changed the friction to 0 on the ground’s StaticBody2D as it was set to 1.

Unfortunately the exact behavior is still happening. I was super excited when I read your solution. Shame it didn’t work. But it must be a guide to what is needed to fix it.

Robster | 2016-08-20 03:16

Sorry it didn’t work. Did you play around with all of the other property values in the editor for the rigidbody2d and staticbody2d?

ericdl | 2016-08-20 03:23

Is there by chance a way I can privately send you the file to look at? It’s very small and focused.

Robster | 2016-08-20 03:26

Sure, you can send it to (email removed) and I will take a look.

ericdl | 2016-08-20 03:33

This is an update for anyone with this issue in the future.

ericdl was kind enough to look at my code. He couldn’t find a reason it was happening but offered the following workarounds:

Workaround #1: ignore tiny y-values.

In func air_state(delta)

changed if get_linear_velocity().y > 0:
to if get_linear_velocity().y > 1:
and changed elif get_linear_velocity().y < 0:
to elif get_linear_velocity().y < -1:

Workaround #2: zero out tiny y-values.

In func move(speed, acc, delta):

add the line if abs(get_linear_velocity().y) < 1: set_linear_velocity(Vector2(get_linear_velocity().x,0))

Either workaround can be used alone, or they can be used together, makes no difference…

(Thank you Eric for helping find a workaround to this problem)

Robster | 2016-08-20 08:24