[GodotPhysics] CharacterBody3D gets stuck on flat ends of static cylinders

[Kalcen]

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Bugsquad note: This issue has been confirmed several times already. No need to confirm it further.

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Godot version

4.0

System information

Windows 10

Issue description

Moving a CharacterBody3D along the flat end of a cylinder does not behave the same as sliding along a flat wall. The CharacterBody3D can even become stuck in place and unable to move away form the cylinder once it reaches the edges of the cylinder's flat surface

.

Steps to reproduce

• Place a CharacterBody3D on a flat surface
• Place a cylindrical StaticBody3D collider near the CharacterBody3D, and rotate it 90° along the X axis so the bottom or top of the cylinder becomes a wall.
• In play mode move the character so that it collides with the flat end of the cylinder, and try to slide along it diagonally like a wall.

(For some reason if the cylinder has its scale set to (2.8, 2, 2.8) and is placed about 1 unit above the surface of the floor the issue is more present)

Minimal reproduction project

CharacterAndCylinderIssue.zip

[Kalcen]

I noticed that this problem doesn't occur if the collider is a polygonal cylinder, like with a CSG cylinder.

[fabriceci]

The problem is related to the contact points returned by the engine, it seems to occur only with this rotation, this could be caused by a bad separation axis.

In the following image you can see the contact points as pink dots::

Same scene but using a CSG Cylinder:

As in the first one, there is no contact point in the cylinder, the body cannot slide and ends up being stuck.

[novaplusplus]

I believe I am encountering something similar but with more than just cylinders, I've been getting it with all collision shapes. Sliding against them just seems very failure-prone and leads to objects getting stuck all the time.

[fabriceci]

@novaplusplus could you share a minimal reproduction project, just the bare minimum with the default script movement?

[prominentdetail]

I am having similar problem..

@fabriceci Here is a minimal reproduction with default script movement:
moveSlideStuck.zip

[Ldi2dier]

I believe I am encountering something similar but with more than just cylinders, I've been getting it with all collision shapes. Sliding against them just seems very failure-prone and leads to objects getting stuck all the time.

Same thing is happening to me. Brush up against a wall? Stuck.

[Dan2552]

@akien-mga was this closed intentionally? I'm still seeing CharacterBody3D getting stuck agaisn't edges on 4.0.2, including on the above example by prominentdetail

[Calinou]

I can confirm the issue still occurs with @prominentdetail's MRP in 4.0.2. I would recommend testing #68958 locally and see if it resolves the issue.

[Dan2552]

Unfortunately still able to reproduce on #68958 (v4.0.beta.custom_build [b812101])

You're able to get stuck on the corner here pretty easily

[psychicgoldfish]

having this issue on 4.1. both cylinder and capsule playershapes get stuck on walls and corners of staticbody3ds.
edit: it has no problem sliding against csgboxes normally, but corners still get stuck and jittery

[Dan2552]

Confirmed still issue in 4.1.1

As far as I can tell so far, this issue doesn't appear to be reproducible when using godot-jolt physics 🤞 . cc godotengine/godot-proposals#7308

[AttackButton]

I tested @prominentdetail's MRP in v4.1.1.stable.official [bd6af8e] with godot-jolt physics and it's working flawlessly.

[cscooper]

I have this problem with the characterbody3d node as well. But my set up does not involve walls. It simply gets stuck moving on a flat surface. I'm using the Kenney Starter Kit for 3D Platformers (https://github.com/KenneyNL/Starter-Kit-3D-Platformer), which includes a platform prefab that I'm using with my own characters made from scratch. I can dislodge my character by jumping. However, I'm not sure how to resolve the problem.

I actually think timing might have something to do with it. It seems to happen after 17 seconds of game play. I will move my character back and forth over the platform, and every 17 seconds, it will get caught on the floor, and I have to jump to dislodge it.

I have attached a video of this happening:

godot.s.weird.bug.mp4

Is it possible that it is my computer?

[Yarwin]

I'm still getting bodies with cylinder as collision shapes stuck while sliding against the wall on v4.3.beta3.official [82cedc8].

[wapcaf]

I am also experiencing this, when trying to move when there is a edge just clipping the top of the capsule collider my player controller uses. The CharacterBody3D does not slide, it gets stuck.

[Calinou]

@wapcaf This should be resolved in 4.4.beta if you switch the 3D physics engine to Jolt Physics in the Project Settings. If not, please open a new issue with a minimal reproduction project attached.