BodyPosition's power is suddenly less

[milanomaster]

After changing the PhysicsSteppingMethod from ‘Default’ to Fixed, it indeed seems to have fixed

The orbs are floating back like normal and the platforms no longer require ‘physical activation’ from a Humanoid (it be a Player, Zombie, etc.)

Regardless of it being ~30 days later, I thank you for the solution (!!), as I was starting to doubt this “update” that I’d be receiving on the issue.

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This does raise some questions…

• What else is affected by the change from Fixed (old default) to Adaptive (new default) PSM besides BodyPosition?

• When I opt to change ‘back’ to the previous default - Fixed - could there be any unwanted consequences it brings with it somehow (new ‘Fixed’ being somewhat different from old ‘Default’)?

• All these other Game Behaviour properties, have they also seen a change from old to new ‘Default’ ?(I’m not sure if I’ve noticed anything else much, but this change has me concerned)

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And eh… will I have to manually update every Sub Place’s PSM / PhysicsSteppingMethod now?
It can’t be done from the Main Game/Experience hub

[radiogamer]

I can find that they’ve recently changed Default to Adaptive back in July (PhysicsSteppingMethod: Now Set to "Adaptive" as Default). I’m not sure if this means that the ‘Default’ option equals Adaptive, or that Adaptive is simply the default setting. I also found some other posts (Issues and physics-related flinging caused by recent Roblox update - #5 by 0Tenth) mentioning that the old bodymovers prefer to work under Fixed.

It basically adds up that Adaptive is now the new Default. Whether this is intended or not is for Roblox to say.

I can only say that this could break various old games. My assumption is that most, if not all bodymovers are affected by this change. Indeed, the only solution is to go into the place, change the property and save / publish that change.

[Hajimalago]

Thanks for reporting, I’ll be taking a look into this to see if we can improve things. Apologies for the troubles.

[milanomaster]

Just changed every Subplace to the ‘Fixed’ PhysicsSteppingMethod.

This inexplicable platform behaviour had me groping in the dark for a long time, unable to find the root or cause to the sudden problem.
Hopefully the manual switching has solved the issue for good and no further complications arrise, as expressed in the message above…

Would’ve preferred the new ‘Default’ to apply not to existing places
Thanks for the help :')

[Hajimalago]

@milanomaster

preferred the new ‘Default’ to apply not to existing places
Thanks for t

Hey MilanoMaster,

Just letting you know that this issue should now be fixed. Using Adaptive as the stepping method should not have noticable impact on the behavior of AlignPositions now.

[milanomaster]

I noticed some changes, yes!

It seems that for all three stepping methods (Fixed - Default - Adaptive), parts with BodyPosition now all feature the same physics.

quick mention:
-The subtle, natural / ordinary dip (0:55 on the clip of first post) always occured to a part with BodyPosition when the power wasn’t on the extreme - even before the change to ‘Default’
-The exaggerated, abnormal / extraordinary dip is the big lack of power (0:16 on clip; until an NPC/Player/Humanoid touches) which this thread was created around

It appears that this subtle dip is now also gone, on every stepping method.
This means for example the platform no longer slightly lowers itself when power isn’t sufficient.
This also means BodyPosition with this insufficient power added to a Player keeps them set in place.

There is this instance where BodyPosition is added to them by this kind of Sorcerer. The force of this BodyMover tries to keep the NPC or Player in place, but you can resist and slowly move away from the point set as its position.

Right now however, after this change from a day or two (?) ago, you’re just stuck and can’t move away or resist whatsoever. This is because the subtle dip (it allowed you to slowly but surely move away) has been gotten rid off on every Stepping Method. When I wrote my latest message (October 17th), changing the Stepping Method to ‘Fixed’ removed the exaggerated dip, but nicely kept this subtle one!

I thought tweaking the Power, Damping and MaxForce would bring back the ability for the Player to resist this force, which after a lot of trying seemed to sort of work.
Something to the movement or force put towards it seemed off however. It felt as if the force wasn’t constant and that with every movement direction I took, I was able to manipulate the force to a point where sudden movements affected the force too much.

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I set up a basic test with a part to check on this:

Roblox stepping method update affecting BodyPosition

You can clearly see the part doesn’t move whatsover, even when the Force is lower. No more subtle drop…
Only when it’s reached a Force low enough - changes occur.
At 0:31, putting in 1100 wasn’t enough to get the part back into the air, whereas on 0:43, 1100 was enough to keep it afloat somehow.
It seems as if it’s “the one or the other” now and the forces impact each other.

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I greatly appreciate the thoughts on how to improve the methods, but with the abnormally loss of power gone and the subtle dip still there (message from October 17) the interactions and physics worked well from there!

Fast forward to today, the abnormal loss is gone, but so is the subtle dip - essentially causing another complication

Was it intended for either Stepping Method to now give the same results regardless, or can one method allow no dips whatsoever and another keep just the subtle one?

Essentially:
~ A few months ago : Subtle dip, worked fine
~ September 14th / Post creation : Abnormal drop
~ October 17th (I updated the stepping method to ‘Fixed’) : No abnormal drop, but still subtle one
~ November 9th : No abnormal drop, but no subtle either

[Xeau (Bane)]

You and I are having similar issues with BodyPositions. I have a game where players fly around using BodyPositions, and I experienced an issue similar to yours where flying players would slowly fall down while idlling when they should have been in a set position. What fixed this was reverting the instance to a previous version history then importing all my newer models to the old place. This fix was great, until sometime around November 7-8 my players report they suddenly are either falling or floating upward but nobody is staying in one place. I will work to find a solution to bring the physics back to what they were and post it here.

Edit: It appears primarily the Y-axis is what is affected like you stated previously. There are little to no differences in regular flight except the slow falling or floating upward.

[Markaaron]

This update essentually ruined the main mechanic surrounding my game. I use BodyPositions to have characters move around while being pulled towards the players. BodyPositions seem to have been broken in away that prevents said characers from move at all except for the force applied by the BodyPosition. There doesn’t seem to be any Class that behaves similarly to BodyPosition before it broke, so this leaves me with no alternative.

[Hajimalago]

Apologies for the issue. Can you send me a placefile so I can further look into any problems?

[Hajimalago]

You can use the non-deprecated constraints to obtain the same behavior. BodyMovers are deprecated and janky, and are on minimum maintainence at the moment Using AlignPosition is a much better choice in 99% of cases.

We will still look into this further though! Apologies for the issues.

[Markaaron]

AlignPosition does not appear to behave the same as BodyPosition as it does not have a Dampening property. If they are supposed to behave the same then AlignPosition is suffering from the same issue that’s affecting BodyPosition. After this change came out, additional forces that can be applied on a character such as walking is effectively nullified when a BodyPosition or AlignPosition with the same properties post and prior to the update is present in the character.

The properties that I have applied to the BodyPosition are
MaxForce is 8000 on all axis
Power is 25
Dampening is 7
The purple character has a Walkspeed of 30 yet it is unable to move at all.

As demonstrated by the video below, you can see that the purple character is trying to run away from the player, however the force applied by the BodyMover entirely takes over all additional forces. Prior to this update, the purple character was able to run around while being pulled towards the player by the BodyMover. I’ve tried changing it to AlignPosition, however the strange behavior continues to persist.

[Markaaron]

Is there a way I can provide a place file privately?

[Hajimalago]

Can you try playing around with the “responsiveness” and “max force” settings to see if you can get what you want with AlignPosition? It will automatically assign a damping constant that will be close to the number required for the system to be critcally damped. I’m pretty confident that this should cover 99% of use cases. If you need a system that is somehow noticably over/underdamped, using a AlignPosition or BodyPosition might not be the right approach for you.

You can DM me your placefile, I can take a look to see if anything isn’t working properly

[milanomaster]

At about October 17th, when I changed the Stepping Method from ‘Default’ to ‘Fixed’, the abnormal drop was gone and the subtle natural one was still there - this brought back the desired behaviour, fixing the issue!

Now (as of around 8/9 November) this subtle one is also gone, causing these new complications
Some Test - 10 Nov.rbxl (73.4 KB)

In this placefile, the Sorcerer and a random NPC can be found. When playing, you used to be able to resist this force - essentially allowing the player to slowly push through, out of the range - instead of being stuck in one place.

Quoted from the previous message:

“I thought tweaking the Power, Damping and MaxForce would bring back the ability for the Player to resist this force, which after a lot of trying seemed to sort of work.
Something to the movement or force put towards it seemed off however. It felt as if the force wasn’t constant and that with every movement direction I took, I was able to manipulate the force to a point where sudden movements affected the force too much.”

The new behaviour appear identical on every Stepping Method. Perhaps one method could provide these new changes, whilst the other retains what the ‘Fixed’ method used to at 16/17th of October

[milanomaster]

Any heads up on the new situation?

[milanomaster]

It’s a month later and I’m still experiencing issues due to this new change.

The initial issue with the abnormal dropping/sinking was essentially fixed when on October 17th, I changed the PhysicsSteppingMethod to Fixed, thanks to RadioGamer’s helpful reply.

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As of the changes November ~9th, the behaviour is left in a state where yes, the initial issue is gone, BUT another issue arose. I cannot alter between these methods at all to resolve this new issue as described in my previous messages.

Both the ‘Fixed’ and ‘Adaptive’ SteppingMethod result in the same BodyPosition physics.
Seeing how Adaptive is the new Default, it’d be great - and all issues would be fixed - if Adaptive continues with the new, current physics (~ November 9th) and Fixed kept the physics of how they used to be before this recent change.
If this may be done, the entire issue would be resolved and creators would have the option to pick between ‘Fixed’ Stepping and this new responsive ‘Adaptive’ method to better suit their work.

[milanomaster]

I still haven’t heard back on this and I’m still experiencing issues.
Feeling left in the dark as there hasn’t been a response on any of my messages regarding this newly arisen issue

[milanomaster]

I am still experiencing this issue.

[milanomaster]

@Hajimalago Any news? I still haven’t heard back.

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[Hajimalago]

Hey! Sorry for the late reply. I looked at the placefile you posted above but not sure what the procedure is to reproduce the issue. Lets start a DM so we can figure this out.