Possible humanoid/physics bug with slopes

Bug Reports Engine Bugs
#1

There seems to be a bug in humanoids where you teleport in the world center after trying to stand on a thin point

Issue Type: Physics
Impact: Moderate
Frequency: Constantly
Date First Experienced:
Date Last Experienced:

Reproduction Steps:

In a blank baseplate, add 2 wedge parts connected to each other and anchor them.
In my character I set the slope angle to something lower than both wedges slope angles

Expected Behavior:
My character will slide down and never reach the peak.

Actual Behavior:
The character bugs out, teleports to center and gives ownership to server for a second (my inputs started having latency in them after the teleport, I assume server took ownership for a while)

Workaround:
None.

I’ve added a copy of my character model i tested with, in case any of my accessories cause the bug. I’ve also tested with a spawn location somewhere else in the world, the character is still teleported in the world center. I tested with a few slope angles, the bug only occurs when the MaxSlopeAngle property is lower than the actual slope in the world (in this case, somewhere around 70-80 degrees, 80 degrees is bug-free, at 70 degrees or lower MaxSlopeAngle the bug starts to occur)

My assumption is that humanoid doesn’t know which direction to slide down towards (or I’m standing in the exact center of an infinitely thin edge)
Here’s the exact place it happened: HumanoidTeleportBug_Repro.rbxl

4 Likes
BasePart.Position returns NaN value?
#2

Thanks for the report! We’ve filed a ticket to our internal database and we’ll follow up when we have an update for you.

4 Likes
#3

FWIW this behavior occurs when certain Humanoid properties are set to contain NaN values. This can happen and is most likely happening due to an oversight in the vector math driving the character controller.

6 Likes
#4

@PeZsmistic is right, there were NaNs being generated.

We have found the source of them and should have a fix rolled out in the next couple weeks!

7 Likes
#5

I just received a report about something similar in my game. The odd thing is that they weren’t on any slopes and instead just spawned at 0, 0, 0. Does this occur if any NaN is generated or should I file a different report?

2 Likes
#6

Since this issue is related to a specific case detailed in the OP, if you can find a way to cause incorrect unexpected behavior in a different manner, you should file a new bug report. Teleporting to origin and experiencing input delay is a symptom of NaN values in certain humanoid properties under all circumstances.

4 Likes
#7

This should be fixed!

4 Likes
#8