Unanchored parts not falling over moving part

[blissful orchid]

hi everyone, in my game the map slowly gets smaller and smaller and when it does the stuff on top of it should obviously fall, which it doesn't. Simple question, how do I fix this?

big brown part is the map while everything else above it doesn't fall once it should (map is no longer under it). All parts are welded to every other part in the building but none of them are anchored

[scenic quartz]

Are you sure nothing in your script is telling it to anchor?

[blissful orchid]

yes 100%

when i drag the baseplate in studio then everything falls

i think its js not updating since the size is changing in a script

[scenic quartz]

Do the unusual ritual put in into ChatGPT and ask it what’s wrong cause I can’t see the code

[blissful orchid]

ill send code

while true do
    repeat
        wait()
    until inRound.Value == true
    local mud = script.Parent
    wait(15)
    repeat
        wait(1)
        mud.Size = Vector3.new(mud.Size.X - 2.75, 20, mud.Size.Z - 2.75)
    until inRound.Value == false
    mud.Size = Vector3.new(812, 20, 812)
    mud.Position = Vector3.new(0, -10, 0)
end```

just this for the size

@scenic quartz

[scenic quartz]

Set collide to false or destroy the parts when the platform leaves

[blissful orchid]

how would i do that

like check when each part should fall

as the baseplayte shrinks inwards

@scenic quartz

id think maybe raycast but thatd be wildly inefficient

[scenic quartz]

No just sent the entire script collide to false gang

[lunar lily]

** You are now Level 7! **

[scenic quartz]

Or after whatever time the platform starts to dissapesr

[blissful orchid]

the game is round based and during the 5 min the platform slowly shrinks until it is nothing. i want things to fall off when the platform is no longer under it, i can't just set everything to cancollide false as that would look right or even work right

[scenic quartz]

Look I’m telling you collisions is the problem here idk how u want to implement the solutions

I could be wrong and it’d just updating you should check first

[ocean haven]

i would run the game and then select a whole building or whatever and make sure nothing is anchored for sure

[blissful orchid]

@scenic quartz @ocean haven i know nothing is anchored as i have 6 different maps and it happens with all of them. the issue is that roblox studio is not updating the parts and making them fall because the part under them was technically not moved/destroyed, it changed size. if i am testing and running the game and i update either the buildings or baseplate then they fall.

some things fall, some dont. the ones that do fall do awkwardly

heres a better example of what i mean. i sped up the shrinking to fit in in a vid.

[manic parcel]

are these unions? i also think the constraints might be a problem

could also be client/server desync but i doubt it

[blissful orchid]

not unions, individual parts

just normal parts

[manic parcel]

you mentioned welds, surely things not welded to each other?

[blissful orchid]

in the city map, yes. the buildings are welded together

builds are welded together so they dont fall apart

[manic parcel]

i meant different buildings welded together

not just the parts in and of themselves

[blissful orchid]

no, dif buildings not welded together

i made sure of that

[manic parcel]

if it's just the physics system then not sure, i found this setting you could try, if it lets you, set it to false https://create.roblox.com/docs/reference/engine/classes/PhysicsSettings#AllowSleep

i dont think there's a part:wakephysics() function

[blissful orchid]

dumb question but what is allow sleep, like is it a property in scripting?

[manic parcel]

physics isn't simulated on sleeping parts. https://create.roblox.com/docs/physics/sleep-system. not sure if this is the problem tho

[blissful orchid]

ah

ok

is there any way to set it to false?

think i found it

[manic parcel]

well going by this you could try setting anchored to true then back to false on the assembly root part https://create.roblox.com/docs/physics/sleep-system#additional-wake-situations

pretty jank way of doing it

but if it works it works 🤷

[blissful orchid]

theres no root part. just models with parts and welds

[manic parcel]

i dont know what that does and the docs have nothing

[blissful orchid]

lol

i assumed it related to the allowsleep thing

[manic parcel]

naw bruh anything that is made up of at least 2 parts and a constraint has a root part.

[blissful orchid]

uh

one sec

[manic parcel]

probably in a news article but i doubt its relevant to here

[grim marten]

Is this in a client or server script?

[blissful orchid]

server

[grim marten]

Or actually

it should work even if on the client

[blissful orchid]

u mean primary part?

or am i dum

[manic parcel]

no

[blissful orchid]

whats a root part i only know primary part

https://tenor.com/view/patrick-star-dumb-empty-head-moron-spongebob-gif-11976325420190756370

[manic parcel]

https://create.roblox.com/docs/physics/assemblies

BasePart.AssemblyRootPart The part automatically chosen to represent the assembly's root part.

i said just do it on this one since it's better than doing it on all parts and the docs say it'll wake if any one part in the assembly does it.

[manic parcel]

but i take it since you don't know what this property is or how to access it despite the docs link, eh, consider using lots of smaller falling platforms as the ground instead of changing the size of a single giant baseplate, and just destroy the falling platforms instead of falling and it'll look the same

again that's all assuming it is related to roblox physics

could be other things too ;o

[blissful orchid]

good point

[manic parcel]

or you're just doing something else dum and thats why, who knows. 🤷

[blissful orchid]

my script only yields a root part for the actual parts, not the model

[manic parcel]

resize is usually weird with physics

[blissful orchid]

explorer

bro i think i just fixed it

😄

[manic parcel]

ey? what do?

[blissful orchid]

alr so i made the baseplate have assemblylinearvelocity which is now (0, 1, 0) so its constantly updatting the parts

[blissful orchid]

they fall fine now and as intended buttttt since it has velocity some of the parts bug out

[manic parcel]

what velocity?

[blissful orchid]

sorry bad grammar

"it" refering to baseplate

[manic parcel]

oh i missed that, hahaha yeah i was thinking that too as a cheap way but that also means everything gonna move. this at the very least confirms it's just how the parts are asleep

[blissful orchid]

yeah

[manic parcel]

setting then unsetting anchored seems the least impactful imo

[blissful orchid]

ig

is there any other way to constantly update all the parts?

besides anchoring

@manic parcel

[lunar lily]

** You are now Level 8! **

[manic parcel]

it's fair to assume this function turns it off

[blissful orchid]

yeah

[manic parcel]

definitely do not recommend turning that off if you can help it, but for now this would at least solve the immediate problem and prove this is the cause

[blissful orchid]

ok

how do i turn it off😭

[manic parcel]

i prefer not to spoonfeed

maybe someone else will, it's literally 1 or 2 lines in a server script.

[blissful orchid]

alr lemme try

[manic parcel]

hmm

i suppose you could anchor/unanchor the baseplate which would do the same thing as anchor/unanchor all the parts

[blissful orchid]

oooooooooooooooh

lemme try

[blissful orchid]

it works but it's really janky

[manic parcel]

physics isn't built to deal with resizing parts very well i guess 🤷

[blissful orchid]

yeah

[manic parcel]

just set the physicsservice allowsleep to false

[manic parcel]

or do this

[blissful orchid]

alr

[manic parcel]

such that instead of resizing a part, you're instead destroying parts. i know that's much harder to work with but it would do the job all the same without having to resort to turning off physics sleep

and you really, really do not want to turn that off.

[blissful orchid]

lag?

[manic parcel]

worst case is all assemblies are constantly sending physics simulation data over network

[blissful orchid]

yeah

i just realized the anchoring and unanchoring works fine, i just forgot to get rid of the velocity

[manic parcel]

and y'know i kinda suspected roblox had a problem like this, it's not unexpected, many other physics engines have the same problem

[blissful orchid]

i think ima stick with that

[manic parcel]

first time i've seen it though. that's why i check these help forums ;p

[blissful orchid]

ye : )

[manic parcel]

minecraft has it's own similar version of the same problem where blocks 'sleep' and only at certain times do they 'wake', aka block update https://minecraft.fandom.com/wiki/Block_update

[blissful orchid]

alr so i guess we found a solution then, im glad i now know what was the issue to begin with

[blissful orchid]

like how gravel and sand will float

on generation

[manic parcel]

yes exactly like that until you trigger a block update, or in roblox's case, a physics wake

[blissful orchid]

yeah

[manic parcel]

exact same thing.

just different situation

[blissful orchid]

well the anchor/unanchor thing works well, as there no difference

thats it then

tysm 😄

[manic parcel]

[blissful orchid]

really appreciate it, i wouldnt have figured this out if u didnt help me 🙂

[scenic quartz]

Type shit