⚛️┃physics

[silver moss]

But tbh I can't think of a performant solution to do this in unity

[dull adder]

I suppose they do not need to be super accurate as the focus of the game is not really "realistic physics"

Also how do I make greedy meshing I could never follow any tutorials ;(

[silver moss]

Iterate over your voxel grid and try to expand the current box in each direction until you hit an empty voxel
Repeat until all voxels have been checked

I've never implemented it, that's just my basic understanding of it

[dull adder]

I suppose that sounds easy

but then how do I iterate after the first box

do I just ignore voxels that are already in a box? I guess that would fix it.

[silver moss]

Something like that

If you can't follow any of the tutorials online though, then maybe it is a bit above your skill level

But give it a try

Look for other ways of doing it too, this was just one idea

[dull adder]

👍

[scarlet field]

i have a spring joint
i set its max and min values to the same thing so now it acts as an inextensible/incompressible tether

but whenever the mainbody is on top of the connected body, it wont fall down/no gravity as the spring counteracts it
how do i make it fall down? (im basically tryna achieve a scenario where the main body stays IN/ON a sphere of some radius whose centre is the connected body but the body needs to have the gravity)

[signal wyvern]

Wondering if you can help, Is there any reason why this script wouldn't work in a build, it works great in the editor but once built doesnt seem to do anything?

Can anyone help? i have a physics related script which works perfectly fine in the unity editor but does not work at all once built, why is this? (Script Below)

[timid dove]

What's the point of the spring?

Are you just looking to make "planetary gravity"?

[narrow pier]

Ensure that ignoring Rigidbodies colliders have hasModifiableContacts set to true. And make sure to not set it in methods like OnValidate that are called only in Editor. I can't think of any other reasons.

[weary pumice]

I have this file for a torch, in unity i put a mesh collider on it and then make it convex, but the torch continues rolling in a circle unless there is something to stop it, how do i stop that?

[scarlet field]

grapple
or
a rope that the player is holding onto and can swing

tried to do it physically by rb.addforce
was janky
and was introduced to spring joints

[scarlet field]

the problem is that whenver the player is on top of the anchor point, he can stay afloat and not fall down

[ashen swift]

i fucked everything uuuup

this is gonna take me weeks to fiiiiixx

plz someone shoot me

can anyone dm me to fix this 1on1

i wasnt aware my guy had to be dynamic

that the main char should almost always be dynamic

and now everything's fucked

[barren marten]

how to make dynamic rigid body not flip in unity 2d i want my charechter to not fall and flip

[silver moss]

With "fall and flip" do you mean rotate?
Freeze the rigidbody's rotation in the Constraints tab in its inspector

[misty compass]

hello I am writing my external library, which simulates the game and I use Unity "only" to visualize the simulation, handle the game loop and do some scene management. Since my physics computing is totally separated from the models rendered, is it beneficial to actually have separate 3D models for each? in other word some simplified models for the physics and some more complex ones for accurate rendering... is this something used in other games? And are there any conceptual drawbacks?

[timid dove]

Different models for physics and rendering are very common. In fact it's pretty common to use primitive colliders instead of MeshColliders wherever possible.

[misty compass]

okey, thanks!

[mystic siren]

hia, I have a problem with projectiles, I'm trying for them to hit an enemy, but they won't trigger upon entering enemy's collider (projectile has "Box Collider with: Is Trigger", enemy has just "Circle Collider"), my guess is that, when the projectile spawns it might be in player's collider and doesn't trigger for other colliders, but I don't have a single idea how to fix it and all my tries have lead to nothing. I'd really apprecieate some healp, cheers!

[elder sedge]

Does anybody know how to use Rigidbody.MoveRotation, even if the Time.timeScale is set to 0?

[royal willow]

You cannot if timescale is set to 0, it acts as if your game is paused and all fixed update functions are ignored
https://docs.unity3d.com/ScriptReference/Time-timeScale.html

[unique cave]

Is there a reason you wouldn't just set the rotation of the transform when the game is paused?

[elder sedge]

Rigidbody.MoveRotation uses interpolation it doesn't snap the Rigidbody's rotation, and I'm looking for that interpolation but with Time.timeScale set to 0.

[unique cave]

With transform.rotation in Update you wouldn't need interpolation though right?

[timid dove]

Just a heads up that asset is now free if you're still interested.

[royal willow]

You cannot use rigidbody.moverotation when timescale is 0, so you could either not use 0 timescale or rotate the rigidbodies transform in Update() and blend it via lerp or slerp or something like that

[elder sedge]

Yeah I'll give that a go.

[hearty goblet]

Hi, I am doing a small project for my learning and i don't want to use any rigid body. just vector maths . I came across this problem.
So this 3d block is moving with a velocity of V1 vector.
Now I am applying an impact force F1 vector at a distance/direction d1 vector from center of mass and another impact force F2 vector at distance/direction d2 distance/direction vector from center of mass.
Now If I want to calculate how much I should deduct from the V1 velocity vector, how should I do that calculation. or approach that problem
I know there will be torque change (i think torque would be Vector3.Cross(d1, f1) + Vector3.Cross(d2, f2)). but i would assume that it would also change that V1.

[timid dove]

What does impact force mean? Is there another object this thing is colliding with?

[hearty goblet]

yes. as an example.. or a ball hitting.. i 'll placccing blocks for now to simulate that

[timid dove]

The characteristics of the collision will depend on the coefficient of restitution of the two objects (think physics material bounciness) as well as the mass and shape of the other object.

[hearty goblet]

i see.. if for example I assume it to have unit mass.. like 1 .. so that multiplication doesn't change anything. and the thing which is creating the impact force is some immovable object.. how would I do that for like one physics frame

oh wait then it would have to be equal to the force this block is moving at i think

[timid dove]

Again it depends on the "bounciness" of the collision. you can do it as a conservation of energy calculation

[hearty goblet]

so for bouncyness some kind of spring constant will come into play? or it just how much of the force it takes it on itself uppon colliding?

i remember spring conststant is just for how much a spring is compressing and appkying force based on that.. but it won't be for this as its just solid block.. 🤔

sorry i'm just confusing myself at this point. just wanted to simplify my thinking a bit

[timid dove]

Not a spring constant, no. That's for springs. It's the coefficient of restitution. 1 would mean a perfectly elastic collision in which all kinetic energy is conserved.

0 would mean all kinetic energy was lost (converted to heat or deforming the objects)

[hearty goblet]

ouu. i see.. makes sense. like how much of the force gets lost in this sense.. in this case it can be 60% of the force is retained in opposite direction.. something like that

[last hemlock]

yo does anyone know how to get magnitude with unity 6? since they changed it to be linear velocity now the normal way of getting it doesnt work properly anymore, currently i have

 void Start()
    {
        rb = GetComponent<Rigidbody>();
        speed = rb.velocity.magnitude;
    }```

wait im dumb actually

nvm, i realised my issue haha

though, can anyone confirm if using linear velocity is better or worse?

[narrow pier]

Before Unity 6 Rigidbody.velocity refers to linear velocity. It's nothing but a property name change (and a good one)

[iron canopy]

getting a crash on Unity 6 when trying to set joint.connectedBody = null; on a Configurable Joint.

the crash occurs on native unity code apparently. didn't occur previously on 2022 LTS. here's the relevant end bits of the stack trace:

0x00007FF95EC30B84 (Unity) Unity::Joint::SetJointLocalActorFrames
0x00007FF95EC27149 (Unity) Unity::ConfigurableJoint::Create
0x00007FF95EC2FAE1 (Unity) Unity::Joint::SetConnectedBody
0x00007FF95E03B6B6 (Unity) Joint_Set_Custom_PropConnectedBody
0x00000265AB9306DD (Mono JIT Code) (wrapper managed-to-native) UnityEngine.Joint:set_connectedBody_Injected (intptr,intptr)
0x00000265AB93060B (Mono JIT Code) UnityEngine.Joint:set_connectedBody (UnityEngine.Rigidbody)```

other interactions/functions of the joint work just fine as far as I can tell, but the moment I try to call `joint.connectedBody = null;` (and I do nullcheck `joint` first, just to be sure) it crashes the entire editor. any ideas?

suspecting it might be a U6 bug but hoping it's just something I'm missing I guess, or a change that wasn't accounted for on upgrade

[last hemlock]

So for safety sake I should change "velocity" to "linearvelocity", if that's the correct syntax?

[narrow pier]

I mean... on Unity 6+ accessing rb.velocity will not compile, so yeah, you should

[mystic siren]

please...?

[royal willow]

the 3 rules of Ontriggerenter:

1. you must have a 3D Collider on each object
2. you must tick isTrigger on at least one of them
3. you must have a 3D Rigidbody on at least one of them

you would also need to give us more information on what your code is, what is happening, etc

is your project 2d or 3d?

[mystic siren]

@royal willow sure, it's in 2d
on LMB an arrow spawns that moves forwards, the point is, so when the arrow is within Enemy's collider, it damages it, and destroys itself. Right now I think it only detects the collider of the player (which it shouldn't) and ignores enemy's collider. The arrow spawns in the middle of the player (this is intended)
some screens (gray is enemy, yellow is player, the third Box Collider 2D is just so the player doesn't fall through the floor)

visible colliders

[royal willow]

you want to use the trigger to detect if the arrow actually hit something, but you are using oncollsionenter2d?
best use ontriggerenter2d
https://docs.unity3d.com/ScriptReference/MonoBehaviour.OnTriggerEnter2D.html

so thats why it is hitting the player collider, most likely

[mystic siren]

oh, thanks

that might be it

[mystic siren]

worked, tysm

although a new foe appeared, any ideas?

[timid dove]

Look at your inspector, have a broken script on some GameObject

Nothing to do with your code

Or maybe a broken reference

[mystic siren]

oh, yeah, that was it lol, thanks

[simple hearth]

Debug.Log($"Force.. {moveDirection}");
ownedProjectile.ownedRigidbody.AddForce(moveDirection, ForceMode2D.Impulse);
Debug.Log("Added.. " +  ownedProjectile.ownedRigidbody.velocity);

What may be going wrong here? It is supposed to add velocity to the projectile so it moves. But AddForce somehow.. doesn't add velocity?

I also tried without specific ForceMode2D and ForceMode2D.Force. I have no clue what else I should check

I could really appreciate any help and suggestions. Thanks

[timid dove]

Show the inspector of the Rigidbody

[simple hearth]

here you go, one of the samples

[timid dove]

It's kinematic

[simple hearth]

yeah?

[timid dove]

Forces don't do anything to kinematic bodies

Only dynamic

[simple hearth]

what should I use instead, for kinematics?

[timid dove]

I don't understand what you mean

Why is it kinematic if you want to add forces

You can always just add to the velocity

That's all that forces do anyway

[simple hearth]

hm, people on the web doesn't recommend adding velocity directly. But you are right, in my case that's going to be right

[timid dove]

No you're confusing setting and overwriting velocity with adding it

As long as you do things additively it's exactly equivalent to what add force does

[simple hearth]

got it, thanks. let me give it a try

Debug.Log($"Force.. {moveDirection}");
ownedProjectile.ownedRigidbody.velocity = moveDirection;
Debug.Log("Added.. " +  ownedProjectile.ownedRigidbody.velocity);

Something is terribly broken in my project at the moment.. lol
I'll look for it, thanks anyway

[last hemlock]

I'm using 6 rn and it seems to be working fine so far, but for the future do we actually know what the correct spelling for it is? Or is it just spelt like how I did it above?

[hearty goblet]

Hi, if i'm doing overlapBox to find colliding.. how can I find the centroid of interaction bettween the colliders?

I don't want to rely on oncollisionStay as that runns on frame rate

[simple hearth]

collider.closestpoint maybe?

[hearty goblet]

in that case i'm getting the green point.. but I want the blue point

[hearty goblet]

this is the same case for compute penetration as well

[bleak umbra]

The blue dot is not well defined, you can’t get that one easily from contacts without analyzing the shape of the object.

[hearty goblet]

maybe if i know the box size will that help?
and the center would be like the center of the intersecting surface .. something like that

[bleak umbra]

well, then you got some math ahead of you.

[hearty goblet]

yes XD that's what I'm looking for. like some kind of direction where to look at or any approach would be appreteated XD

[bleak umbra]

You just answered your own question, construct the intersection shape from the colliding plane and your object, find its center (also not a unique property of a shape)

potentially do that for a triangle decomposition

[hearty goblet]

yes.. like getting the intersection shape. meaning do I need to calculate based on the vertices position of the colliding mesh?

i see

[bleak umbra]

All I can say is that this probably isn’t something that’s easily solvable in a fully generic way because triangle meshes always produce edge cases when you try to calculate a cut

You could look into Boolean operations on poly meshes. Most 3D modeling apps have those, but none exist that always work.

this stuff is typically not fit for realtime modification

[hearty goblet]

hmm.. so lot of experimentation .. was thinking.. like in unity a very simple way would be to get vectors of the edges of the box.. and the normal plane of the colliding point.. now if i get the intersection point.. maybe that might help in a way.. but lets see

[bleak umbra]

If your colliding shape is a primitive, a pure math solution based on analysis of the colliding primitive shapes would be more reliable. In modeling terms that would be constructive solid geometry.

[bleak umbra]

What do you need that point for anyway?

You could cluster contact points (via k-means and such), get the center of that cluster

[hearty goblet]

like trying to find the point of force.. i'm manually trying collision.

[bleak umbra]

If you have only convex shapes, there is only one cluster of contacts

[bleak umbra]

You can calculate that from the change in momentum

[hearty goblet]

that change in momentum i'll be applyling based on the point

[bleak umbra]

why?

[hearty goblet]

i'll be manually doing the physics. this is like a learning/experimentation

[bleak umbra]

Why not use the contacts?

[bleak umbra]

Then first thing to learn is to not do crazy things like that

[hearty goblet]

lol XD

i guess truee

[bleak umbra]

I would aim to solve by using the easily accessible information first, maybe aim for an approximate solution

[hearty goblet]

yea.. lets see what I can do for now

thanks 🙇🏼‍♀️

[iron canopy]

late to this, but it's just deprecated in 6 - the updated name is myVar.linearVelocity. no telling how long the deprecated name will continue to work, but you should be getting a warning about it already if you're on the latest Unity 6.

[signal wyvern]

Does anyone know of any good FPS RB player movement scripts out there? I want to avoid using a character controller

[royal willow]

Yes there are plenty on the asset store and on github, tutorials, and im making a half life/1/2 quake movement FPS controller for release but its not out yet (shameless plug), also next time ask in #💻┃unity-talk for better answers

[vivid plaza]

Hello I'm having this weird issue when using WheelColliders where this one wheel somehow spins super fast, despite all wheels getting the same torque and having exactly the same stats.

[last hemlock]

Cheers and thanks, I'm gonna change it next time I get on, just wanted to confirm the syntax for it

[vivid plaza]

Nvm I found the issue and solved it

[blissful flume]

not sure if this is the place to ask, but could someone help me understand how to set up hollow colliders properly

I have this basic ass pipe, but I simply cannot get the mesh collider to be hollow

[vivid plaza]

You need to use the mesh data as the colission object I think

[narrow pier]

What exactly is a problem? Assure that the Convex option is disabled.

Don't worry about not seeing the green outline of a collider. Unity doesn't render gizmos for concave colliders.

[timid dove]

If it's static you can use Mesh Collider.

If you need it to move you need to make the collider out of smaller primitives

[blissful flume]

Sadly it is not static

[timid dove]

I.e. you could do 32 long Box Colliders

[blissful flume]

Ew

[timid dove]

Arranged in a ring

[blissful flume]

I'll get to it then

Thanks

I did think of that but assumed there must be a better way

[simple hearth]

Hi there! I'm having some performance problems with Unity Physics2D, and I would like to improve it if it's possible. I have 264 projectiles(Kinematic moving trigger objects) with RB2 and Circle Collider 2D

Projectiles ONLY collide with Hostiles and Player, a.k.a dynamic moving objects with circle colliders(52x). For testing purposes, current Fixed Timestep is 0.05f.

I would like to hear out your recommendations about optimizing the Physics to have more projectiles in the scene. The game is a kind of bullet heaven, so it's critical to optimize the physics of projectiles.

At the moment, I'm thinking of removing Rigidbody2D&Collider2D and Raycasting each FixedUpdate to get any collisions.

Oh I'm just going to add the info, the same game was able to handle 1200ish "Hostile" with both RB and Collider. It's somehow just the projectiles that cause problems. I guess it's about that they are not as distributed over the map as the "Hostile"s

My "Hostile"s are childs of WorldCanvas, since they have healthbars attached.

My Projectiles are childs of an empty game object called "Projectiles"

(from another test)

How is it even possible to have 38125 trigger stay callbacks in a single frame with not-that-many objects

it exponentially goes higher and higher as more projectiles getting fired.. this means projectiles send triggers to each other? even if I disabled it in matrix?

[oak trout]

how are you testing this

post a picture of how the scene looks like

Box2D V3 is a lot faster than the current version in unity

i think they want to get it ready for unity 6 release

it's very parallelized

https://youtu.be/dAoM-xjOWtA

if you don't already know, Unity 2D Physics = Box2D v2

[simple hearth]

I have been trying to identify the problem, and it turns out that there were some "detectors" on each object that were in the same layer with their "hostile" owner. Since the detectors are being used to detect nearby "hostile"s, their collider were too big. Since it's too big.. you got the rest. It ended up with arrows constantly sending signals and causing trouble

[oak trout]

yea that was what i thought, was gonna say your colliders were definitely overlapping

[simple hearth]

it's like this at the moment, looks completely healthy for 850 projectiles

[oak trout]

this should take your game into the next level

[simple hearth]

the game is still 5 fps with 850 projectiles, which is far from my target, but still better than a couple hours ago :p

[oak trout]

instead of 850

increase it to

100K

lol

[simple hearth]

I'm interested in it, is it available to public though?

[oak trout]

lol?

start fresh in an empty project

you have some serious issues

[oak trout]

not yeat, they want to get it ready for unity 6 release, box2d is not developed by unity

[simple hearth]

deep profile + unity editor and not well optimized code be like that.. lol

It'll get better by optimizations, I hope

[oak trout]

what are you trying to do

just shoot projectiles around?

that should be pretty simple and basic

shouldn't be that slow

though i wonder

why are they rigidbodies

do they collide or they just explode when they hit something

[simple hearth]

they are just trigger objects with kinematic rigidbodies, isn't it the default way to get hit callbacks for projectiles?

[oak trout]

that is the inefficient way, yes

[simple hearth]

I was thinking of converting it to simple raycasts on fixed update

[oak trout]

the efficient way is to integrate their motion yourself and use physics queries

[oak trout]

yes

[simple hearth]

hmm, do you think it's going to be better if I implement that?

like getting the velocity, delta time and checking if it hits

[oak trout]

of course, a rigidbody has a lot of overhead my boy

[simple hearth]

yeah, since it wasn't the only problem, it wasn't my priority by far

[oak trout]

but you don't know how to use physics though

learn that first

no way you are getting 5 fps for 800 bodies

is your pc from 2001?

[simple hearth]

hahaha, nope. They are not simple projectiles though, each of them may have custom behaviours. Thus, they have the system for it implemented

like some of them explodes on hit, some of them chains etc

and you add those effects through third party dlls

[oak trout]

how many were exploding each frame

[oak trout]

lol?

modding u mean

[simple hearth]

yeah

[oak trout]

does not matter

check what is eating your framerate

is it the physics system

or you own code

[simple hearth]

yeah, I'm working on it. It was the physics system due to my stupidness, but now the profiler says that my code sucks. So I will work on it

thanks btw

especially about the raycast thing

because I wasn't sure

as you said, I don't understand physics..

[oak trout]

can be another physics query not only a raycast

[oak trout]

you only get better

[fresh nimbus]

hey... i need help with a model that keeps wiggin out

[oak trout]

it's a rigidbody?

if not, wrong channel

[fresh nimbus]

yes

idk why

[oak trout]

looks like a problem with your rig or animation

how is it related to physics

[fresh nimbus]

is there a rig xhannel or am i just blind

[oak trout]

https://discord.com/channels/489222168727519232/502171313201479681

[simple hearth]

it's definitely not here

[fresh nimbus]

ok

thx

[hearty goblet]

childTransform.position = parentTransform.TransformPoint(0,-22f,0);

When i'm setting value on y axis to -22f. i'm getting wierd result.. its not accurate..
when I'm printing childTransform.localPosition i'm getting (0.00, -0.22f, 0.00) but when I'm priting childTransform.localPosition.y I'm getting -0.2199993
anyone knows why its not setting accurate value.. but also why childTransform.localPosition and childTransform.localPosition.y is different

is there a way to set accurate value? when i'm setting it to zero.. then it works

[narrow pier]

Unity logs vectors with floats rounded to the nearest hundredth

[hearty goblet]

okay then why (0.00, -0.22f, 0.00) setting this manually.. giving me incorrect values? like -0.2199993

[narrow pier]

Floating point error?

I'm not sure

[hearty goblet]

🥲

[narrow pier]

It's too close to zero to be an error. Something finicky

Maybe transform function is messing it up

[hearty goblet]

hmm maybe. i'll need to see if anything else is modifying the transform in any way

[narrow pier]

Btw, why use TransformPoint anyways? Just set local position of a child

[hearty goblet]

like this? childTransform.localPosition.Set(0, -22f, 0);

[narrow pier]

Oh, wait I'm stupid

You can do that

[hearty goblet]

woh.. that worked

but .SET should also worked Xd

[narrow pier]

Yup

[hearty goblet]

somehow child.localPosition = new Vector3(0, -22f, 0); worked XD
but this didn't childTransform.position = parentTransform.TransformPoint(0,-22f,0);
and this didn't childTransform.localPosition.Set(0, -22f, 0);
I wonder if there is any reason.. maybe some internal calculation approximation is happening which is not making the setting of the value accurate

Thanks man

[narrow pier]

I shouldn't be helping people when I'm barely awake, lol😵‍💫
Just remember that getting a struct makes a copy of it. By using childT.localPosition.Set(whatever), you're taking a copy of a Vector3 and then modifying that copy without changing the original Vector3.

[wispy patrol]

How do I reference who instantiate a Raycast hit? https://docs.unity3d.com/ScriptReference/Physics.Raycast.html

I think there's a way to do this with colliders, but I forget

[unique cave]

what you mean by "instantiate a Raycast hit"?

[wispy patrol]

The player that did the Raycasting

For example, if a player clicks on a tree, to then reference the player that hit the tree

[unique cave]

Sounds weird question, the script that calls the Raycast method is in that object so .gameObject should do in that script?

RaycastHit does not store any information about the caller in case you wondering

That's because it would be just a waste of space for the reason mentioned above, the caller should obviously know which object it is on using .gameObject

[wispy patrol]

It's because I have another method that takes RaycastHit as an object.

Which gets called from a difference class

[unique cave]

If you need to know the object there, you would just pass it as secondary parameter as well right?

[wispy patrol]

It's just that I have so many paramaters already

You bring up a point that works though

[unique cave]

that's what you gotta do though. If you have already so many parameters that the code starts to be hard to read, you may want to look into ways to refactor that part

You can for example create your own data types in a form of structures to be used to hold all or some of the parameters

[wispy patrol]

Incredible. And you're a student?

Man, a lot of these students should be giving top jobs already

[unique cave]

Wish that was the case 😁

[wispy patrol]

Good luck!

[jagged canopy]

Does anyone know why my mesh collider is only generating a triangle-like shape for this box model? (I'm using a mesh collider because the box model isn't perfectly 90 degrees per corner, it's slightly sloped on top)

It's missing 3 corners

Can confirm it isn't a gizmo bug either. the expected code runs when i enter it in the corners that seem to have the wireframe but not in the corners that look like it doesn't have the wireframe

[unique cave]

Assuming it’s not an issue with the mesh like some of the faces inverted, seems like a clear bug. In the latter case, you should maybe send a bug report with steps required to reproduce especially if it’s one of the more recent unity versions. That mesh looks like simple box collider would do better job anyways though

[jagged canopy]

Definitely seems like a bug. This is just one of dozens of little shapes that this is hapening to. some are too complex for a simple box collider. just used this one as an example because its easy to see what's happening

[unique cave]

Are you using an LTS release or an beta version?

[jagged canopy]

LTS

[unique cave]

Does it happen for every shape you have? It would be impossible that nobody noticed it and it wouldn’t be fixed by now unless it happens only in some very rare circumstances

[jagged canopy]

just a series of shapes i imported from blender. I don't understand what it could be though, a lot of them are simple 8 vertice boxes. all vertices are welded together. no funny business that i can see. normals are all correct

[unique cave]

This seems very weird problem indeed assuming there’s nothing in the meshes that would confuse the physics engine. You could try to recreate the same issue in different scenarios (different unity version, new empty scene, entirely different mesh) to gain more insight as to under which circumastances does it happen.

[river flare]

When the car hits a character, it suddenly stops. I suspect this is due to the colliders. How can I achieve smoother physics similar to GTA 5? it works better when done in slower

[light gate]

What mass values did you set for the rigidbodies

[river flare]

car is around 2k and the person is less than 10kgs

[unique cave]

how are the players being moved?

[river flare]

navMesh

players has a trigger collider on the body to detects hits then if it gets hit by car or health is zero then its body colliders gets enabled hence the ragdoll concept

[unique cave]

so is all of the players colliders just triggers?

[river flare]

no just one trigger and body parts are colldiers

[quick mortar]

so is it slowing down because its hitting the ragdolls?

[unique cave]

well, the body parts will obviously act as static objects then if they don't have a rigidbody in them/one that isn't active

[river flare]

yes is it, but just before that the player dies due to the collider being first hit by the car so then player dies and charecter becomes the ragdoll

[river flare]

they do have RB

[unique cave]

non-kinematic (sorry for the typo) one at the time of the first impact?

[river flare]

the RB becomes enalbe when the player dies

[unique cave]

but if the rigidbodies are kinematic when the car colliders with them, they will be considered static and hence the sudden stop

It's like running into fully rigid pole

[river flare]

yea i got u

ur right

well then what could be better approach

[unique cave]

Do you need the body part colliders before the car hits them?

[river flare]

idk man i just wanna effect like a gta when u hit npc

[unique cave]

It is kinda relevant though. The thing is, you cannot have static colliders on the player if you don't want to bonk into it like that. Either disable the colliders and enable them when the collision happens or make sure the car doesn't interact with them until the hit happens, that you could achieve by using the collision matrix and layers to make sure they don't collide and change the layers of the ragdoll when the collision happens. I wouldn't be surprised if in GTA the player body parts were active bodies all along and moved using physics but I don't really know how they have implemented it. If you are interested in that, you may want to research active ragdolls but in your game you might get away with non-active ones and activate them when needed

[river flare]

ok buddy thanks for having ur time here

i increased the trigger collider for the charecter and its working.

but i will find a better way since a large trigger on the charecter isnt a good design

[unique cave]

Sounds very questionable solution. I bet you will still encounter the exact same problem if you drive at the player at high enough speed

[river flare]

yea i did encountered

[unique cave]

@river flare Btw one very unfortunate limitation of triggers is that they don't care about continuous collision detection so you could always drive over the player without a notice if you drive fast enough. That's one reason to consider some sort of active collider solution for the player but depending on the speeds you are operating at that may or may not be a problem

[visual cove]

I've made a system that when the player touches a trigger,some objects start to fall (they are fixed by normal) but when they reach other objects,they go thru them,Both the other objects and the falling objects have colliders and rigidbodies.Does anyone know how to fix?

[fast thistle]

I'm working on a game with a combo system, and I'm thinking to use Linear Programming to evaluate if Attack attack0 can combo into Attack attack1. E.g. Suppose:

• character0 uses attack0 and hits character1
• character1 moves from position0 to position1, and is in hitstun from t0 to t1
• Suppose character0 then tries to cast attack1:
  • Will attack1 become active before t1?
  • Will attack1 be able to reach position1?
    Am I crazy, or is this feasible? I haven't made use of LP much yet, but given how I remember it, I think I'll need to model with some heuristics to make the method work.

[timid dove]

Presumably something is off about your setup. Can you show the inspectors of the two obejcts which should collide? (i.e. the falling object and the "other" object)?

[visual cove]

Falling Object:

Ground:

[visual cove]

here

[timid dove]

your collider is a trigger

[visual cove]

yeah cuz I need it as a trigger too for a script

the falling objects are obstacles and I want so if I touch them to lose

cant I made them work even if it is a trigger?

[visual cove]

or is it even possible to make it work by still being a trigger?

[timid dove]

triggers do not physically interact with anything

If you want you can use two separate colliders

one trigger and one not

[visual cove]

Oh,didn't think about that,thank you so much

[normal wren]

Vector2 inputVectorLook = inputActions.Player.Look.ReadValue<Vector2>();
hoverLook?.Turn(new Vector2(inputVectorLook.x, 0F));

public void Turn(Vector2 turnDirection)
{
turnDir = turnDirection;
}

private void FixedUpdate()
{
rb.AddTorque(Vector3.up * turnDir.x * horizontalTurnSpeed * rb.mass, ForceMode.Acceleration);
}

so I have the above code (I have no idea how to paste code in discord let me know), to turn a spaceship left and right

it mostly works, however if I give tiny taps or small joystick movements no turn happens at all, and just jumps to big movements if you hold the key or bigger joystick movements

can you see what I'm doing wrong to have gradual and controllable turning through physics here?

[timid dove]

not enough context here. It's unclear when and where and what triggers a call to the Turn function

which is crucially important

Also !code

[flint portal]

Posting code

📃 Large Code Blocks

Use links to services like:
https://gdl.space/, https://paste.ofcode.org/, https://hatebin.com/, https://paste.myst.rs/, https://hastebin.com/

📃 Inline Code

Surround code with three backquotes. Not quotation marks.
To format as C#, add cs to the first line:
```cs
// Your code here
```
Add a comment with a line number if there is an error message.

[normal wren]

thanks, I literally just solved it with:

        public void Turn(Vector2 turnDirection)
        {
            turnDir.x = Mathf.Lerp(turnDir.x, turnDirection.x, smoothingFactor);
        }```

sorry for inadequate context

[vale field]

Hi, I've been attempting to make a trajectory calculator, but it's not accurate, probably because I have very little understanding of unity's physics system. Could anyone tell me the mistakes I am making in this script? https://hastebin.com/share/uwanegoxuz.csharp

https://hastebin.com/share/jofiquzega.csharp

[timid dove]

You're not doing any accounting for time here...

Vector3 nextPosition = position + velocity;```
you need to involve Time.fixedDeltaTime because that's how much time elapses each physics frame.
```cs
Vector3 nextPosition = position + velocity * Time.fixedDeltaTime;```

Likewise the new velocity calculation should be:

velocity += gravity * Time.fixedDeltaTime;```

(that one assumes no drag)

I think you should get rid of drag for the moment to simplify things, then add it back later.

[vale field]

Like I said, I've got no clue how this stuff works😭

Thank you though, I will try this

[signal wyvern]

I have a RB player movement set up, and my player need to be able to stand on various moving boats without sliding off, whats the best way of solving this issue?

[timid dove]

Are you strongly attached to Rigidbody?
I recommend the excellent https://assetstore.unity.com/packages/tools/physics/kinematic-character-controller-99131

the demo scene literally has a moving boat in it

which works wonderfully

https://youtu.be/jL2VrEuCaQ0?si=B-bM67NOxTE7tk4p&t=93

[signal wyvern]

Unfortunately i kinda need to use an RB set up as im also using some selective Kinimatics, and that script can only work with RBs

but i will take a look anyway

[timid dove]

Tilemaps have an overall collider with TilemapCollider. It's not generally advisable to create individual GameObjects for each tile as it will be extremely inefficient

[stuck bay]

What is the best way to learn quarternions

[timid dove]

stop trying to learn how the underlying math works, and just learn how to use them

To wit:

• A quaternion is simply a value/variable that represents a particular rotation
• You can combine rotations with the * operator to "compose them". A * B means "apply rotation A first, then apply rotation B"
• Get familiar with the various ways to create a rotation such as Quaternion.Euler Quaternion.FromToRotation Quaternion.LookRotation

that's basically all you need to know

[stuck bay]

And what was the 4th parameter in quaternions

[timid dove]

I have essentially zero understanding of the underlying math (long forgotten) but use them daily.

[timid dove]

again, not important

if you're asking that question, you don't know what the first 3 parameters are either

and it doesn't matter at all, it's a distraction

ignore the internals and the math behind it

[stuck bay]

Are you speaking from experience of learning quaternions

[timid dove]

Yes

[stuck bay]

🤣

[timid dove]

I use them every single day without struggle

[stuck bay]

Okay

Thanks

[dull jungle]

If you are just working with x,y,z rotations you can end up in a gimbal lock, so unity internally uses quaternions which solve this but are not human readable anymore, its like trying to understand how the generated bytecode of your c# code works, you wont need it

I also remember it has some computational advantages but without reading into the topic again I am not able to list them

[timid dove]

More likely a bug in your code

or a quirk of your scene setup

[inner thistle]

The code uses that if the raycast hits nothing or if it hits a trigger, and it hit a trigger

[timid dove]

right so - again - it's a problem with your code, not a unity bug

[signal wyvern]

Anyone got any decent solutions to the problem of falling of moving objects both moving using RBs, I dont think velocity matching is a very reliable approach? Once letting go of the steering wheel my player slides off

[verbal mirage]

Has anyone figured out how to make tank-like movement that correctly handles slopes? In my experiments with trying to make such movement, I've found that Unity's default physics likes to have moving objects jump off slopes rather than just crest over and down the slopes

[oak trout]

quaternions are the most complex thing in all of game development

no one understand them, but everyone use them

I lied, they are not really that complex, it's because they are not taught correctly

this is how they are taught correctly

https://marctenbosch.com/quaternions/

[versed agate]

Hello, I have a problem with physics. How can I synchronize the rotation of an object around its axis with its movement? I mean, when I rotate and move the object, it seems like the character slows down and there are frame glitches. How can I change this to make it work?

[timid dove]

How can I synchronize the rotation of an object around its axis with its movement
Unclear what you mean by this. Can you show a picture of what you want or something?

I mean, when I rotate and move the object, it seems like the character slows down and there are frame glitches. How can I change this to make it work?
How are you rotating and moving the object?

If you're moving the object outside the physics engine, it's going to cause havoc in the physics engine

[versed agate]

!code

[flint portal]

Posting code

📃 Large Code Blocks

Use links to services like:
https://gdl.space/, https://paste.ofcode.org/, https://hatebin.com/, https://paste.myst.rs/, https://hastebin.com/

📃 Inline Code

Surround code with three backquotes. Not quotation marks.
To format as C#, add cs to the first line:
```cs
// Your code here
```
Add a comment with a line number if there is an error message.

[versed agate]

https://hatebin.com/uqlggphluk

[timid dove]

            transform.rotation = Quaternion.Slerp(transform.rotation, targetRotation, Time.fixedDeltaTime * rotationSpeed);

you're rotating the object directly via its Transform

that will break Rigidbody interpolation

causing it to jitter

[versed agate]

thx i solved, rigidbody.MoveRotation(Quaternion.Slerp(r...

[verbal geyser]

Not sure whether to post this in physics or animation, but it's really about the joints system and setting up ragdolls so 🤷
Is there any good tool/wizard (apart from the Unity "Create Ragdoll" window) that speeds up the process of setting up ragdolls?
The reason I don't want to use Unity's solution is that it's too detailed and I wish it could better handle simpler rigs with fewer bones.
Half-tempted to write my own solution, but that's for a future project when I have more experience with the joints system.

[cold quest]

Hi! I need a little bit of help. I want to make a stack tower game and when I press click the block drop on the other block. The problem is that the block is slippery by itself and bouncing at collision. How to fix this?

[round willow]

I've got a "game" where a ton of balls are spawned in, they bounce off a plane and keep bouncing forever. It works fine when I run it in the editor, however when I run & build it, a few things go wrong:

1. The balls don't seem to have random amounts of force applied to them
   The code I use for this is: Vector3 direction = new Vector3(0f, Random.Range(1, 10), 0f);, GetComponent<Rigidbody>().AddForce(direction);
2. The balls don't appear to have gravity?
   The balls get stuck at some random point in air, they don't go up any more and they then don't come back down.

[rotund pelican]

why does the axis field on config joints behave like that? i have to type in extremely high or low numbers just to get it to point in a certain way

[timid dove]

Which way did you want it to face and what did you type in?

[rotund pelican]

ive fixed it now. i wanted it to face downwards but every integer kinda increases it reverse exponentially if u get what im saying

like 1 rotates it 45, 2 rotates it 22.5, etc etc

i had to type in -9999999999999999999999999999 so it would face that way

[lucid peak]

i'm making a 2d game and i have a problem, why when i jump and go in a wall (collider box 2d) my character stick to it as long as i keep pressing the button to go forward

[loud ridge]

I had the same problem couldnt solve it

[royal willow]

either use a physics material and calculate friction forces on your own or use a raycast when moving to a wall to disable input or disable forces moving your player

I do the former since im lazy 😁

[lucid peak]

which one is more practical in a serious project ?

[royal willow]

whatever you think fits best

both are great, if you already are calculating friction forces yourself to the former, if not you can do the latter

if you want to do the former either way, go for it. its really up to you

[lucid peak]

how to "calculate friction" ?

like just create a physicsmaterial2d and playing with friction parameter ?

friction = 0 works for me, hope it won't cause issues for later

[royal willow]

when on the ground add a force negative to the current velocity by so much to slow you down over time till you come to a stop and use a physics material 2D to not stick to walls

you could also make a another collider for walls specifically and add the physics material 2D to that to not stick to walls and not calculate friction forces

[lucid peak]

i justs put a material (friction = 0) on the collider (wall) and it works fine

easiest way ig

[royal willow]

as long as your player cannot stand ontop of the wall, you should be okay but if you have a bunch of walls it will be more time consuming to add another physics material for every wall

[lucid peak]

why it would be a problem ?

[royal willow]

your character will act like it has zero friction if ontop

[lucid peak]

it doesn't seems to cause any issues if i walk on a colider with 0 friction

[royal willow]

is your character raycast based and are you already making your own friction forces/speed limiting

[lucid peak]

another question which has no relation, how hard is it to make a counter system like in sekiro ?

in 2d

[royal willow]

I'm not sure how to make a parry attack in 2D, I would it.

[lucid peak]

you know how to in 3d ?

[royal willow]

Im not a 2D guy

[lucid peak]

Im a 2d guy only xdd

[royal willow]

I haven't done it before so probably no

I most likely can whip something scrappy up but it wont look good, or it may not be good at all

[lucid peak]

and some sorte of posture like in sekiro ?

[royal willow]

I dont know what sekiro is

so I cant really tell you, but best google it or look for a guide

[lucid peak]

it's a souls like based on parry

and if you succesfully parry attack the ennemy is gonna accumulate parry posture and if it reach max he will be killable

i don't know if it's well explained

[royal willow]

ah thats what you meant by posture, yeah sorry I dont know how to

[lucid peak]

it's ok it's not for now I just want to know what I'm getting into

but thanks a lot dude have a great day

[storm spruce]

I'm going insane why does the player get stuck on this specific box...or how do I make the collision less garbage probably

[rich lynx]

Has anyone ever had this happen in their game,

[tender gulch]

Did you change the fixed time step setting maybe?

Though,it's weird that it's colored as "other" in the graph.

[inner thistle]

Not a physics question but make sure the pivot point is in the middle of the log

[visual cove]

oh really?im sorry ima try to change the pivot then,thanks!

[versed agate]

Hello, I have a 3D character with animation and movement through physics. Could you please tell me how to make it so that even if the character bumps into a wall, they can slide off it?

[silver moss]

It's not clear to me what exactly you mean, maybe show a video?

Do you mean like this, where the character runs into a wall at an angle and you want it to slide along it instead of stopping?

[versed agate]

yes

[royal willow]

here's a good collide and slide algorithm
https://www.youtube.com/watch?v=YR6Q7dUz2uk&t=90s&ab_channel=PokeDev

[normal leaf]

Does the Two Bone IK not work with ragdolls?

[versed agate]

thx

[mossy swan]

Quick question if anybody knows off-hand.... are trigger colliders swept using the continuous collision detection mode? I assume not, but can't find confirmation. thanks!

[bleak umbra]

depends on the exact settings, generally triggers are treated the same as solid colliders in the initial detection phase. to be sure for your settings, try it in all relevant cases. if performance and control are a concern, use a sphere/capsule/box-cast.

[mossy swan]

Yeah, that's what we're trying to figure out - if we need to swap to a cast, because triggers are not swept. The behavior we're seeing implies they aren't, but couldn't find any documentation to confirm either way.

[bleak umbra]

https://docs.unity3d.com/ScriptReference/Rigidbody-collisionDetectionMode.html

its not a sweep in the sense of a box cast, there are optimizations going on that may make it behave somewhat unexpectedly

for something like projectiles a -cast/overlap is always gonna be more reliable/debuggable

also mind that not all modes work with kinematic movement (i.e you can't speculate without a velocity)

[unique cave]

@bleak umbra I thought triggers never use continuous collision detection. Has it changed at some point or have I been wrong all along?

I don't see it being documented anywhere but I see comments about it all over the internet, I should maybe do my own test

[unique cave]

@bleak umbra @mossy swan Sure seems to be the case at least on 2022.3 that I tested on. If the object moves fast enough (using velocity) to get past the other object within one physics frame, it will go straight through without a notice to OnTriggerEnter regardless of the Collision Detection Mode used and regardless of which of the objects is set to trigger or which is trying to detect the collision. With OnCollisionEnter the hit is being detected correctly when neither of the objects is set to trigger. Although very poorly documented by Unity, this seems to be one clear disadvantage of using triggers that exists

[bleak umbra]

Good to know. Maybe I’ve always used triggers only together with raycasts so the situation never came up.

[unique cave]

For me at least that makes triggers pretty much useless (except for casts) for most use cases because of tunneling issues. It's really silly by Unity to not make triggers support collision detection modes and not mention it anywhere, at least I haven't found it anywhere which clearly indicates it's not documented properly. There might be some technical reasons why it's not supported but mentioning it somewhere shouldn't be too much to expect. I found a lot of questions online of people asking about tunneling issues with triggers and most answers just suggest using continuous collision detection and links to videos about collisions, not triggers. It's really hard if not impossible for new users to somehow know that this feature does not exist even though it intuitively sounds like it should

Just made a ticket on the documentation page but doubt they will do anything given how long the information have been missing already

[mossy swan]

Yeah as suspected then. Thanks for testing. Also wish this was documented somewhere.

[unique cave]

Just give them decade or two and they will rework all their documentations

[bleak umbra]

I’ve always looked at triggers as a spatial lookup feature, not something i would expect to be used in a highly dynamic context where tunneling would be an issue, for that i would always prefer to use raycasts. I also view physics simulation largely as a visual effect, not really concerned with precision/gameplay

i find the conflation of these two aspects (lookup and force simulation) in one system (rigidbody/collider) to be rather confusing for the casual observer

I see people frequently reinvent either aspect due to misunderstanding

[versed agate]

hello how to make staris climb? 3d person controller

[royal willow]

shoot a raycast pointing down at knee level if the raycast hits a step move your character controller or rigidbody up by a certain amount

but what I prefer instead is making your CC or RB raycast based so you don't have to do any of this, both work, both are good

[silver moss]

A lot of games fake this by having a smooth ramp collider for player collision instead of a stairs-shaped collider

You can use layer-based collision if you want to have a precise collider for other stuff hitting the stairs

[royal willow]

or use a raycast based player and dont worry about any of that

[modern hare]

The best way to do it is to actually have two colliders. The standard stair shape one that is exclusively for IK, enviromental collisions like bullets etc., and the standard ramp for movement.

[silver moss]

Yeah, thats what I meant when I mentioned the layer based collisions. One collider for each purpose

[vivid plaza]

Heya, I'm currently making a car game. The bot ai I'm making uses raycasts to look for obstacles. It works on not moving obstacles, like walls, etc. However, even though the raycast is supposed to, it somehow doesn't detect other enemy cars or the player.
Does anybody know what the reason for this is?

[timid dove]

your raycast isn't in the right place to hit them, or they have the wrong layers, or you have the wrontg layer mask, or you think they are somewhere they aren't.

impossible to say without any details

[silver moss]

Need more details. Do the other objects have colliders? Are they triggers, are you using a layermask

[vivid plaza]

Yes I am using a LayerMask. The Layer on the objects that should be hit by the raycast is included in the LayerMask though. Yes, the objects that should be hit do have colliders with that layermask. No, they are not triggers.

[silver moss]

How are you creating the layermask?

[vivid plaza]

A Serialized variable from the script that does the Raycasting

[silver moss]

Just making sure that you are using a layermask and not a layer

[vivid plaza]

It is a LayerMask, not a single Layer.

[silver moss]

Show your raycast code?

[vivid plaza]

Sorry that it's an image, I can't copy and paste the text because I don't have Discord Nitro and that limits the amount of letters I can type

The function is called in FixedUpdate()

[silver moss]

Next time use !code but its fine

[flint portal]

Posting code

📃 Large Code Blocks

Use links to services like:
https://gdl.space/, https://paste.ofcode.org/, https://hatebin.com/, https://paste.myst.rs/, https://hastebin.com/

📃 Inline Code

Surround code with three backquotes. Not quotation marks.
To format as C#, add cs to the first line:
```cs
// Your code here
```
Add a comment with a line number if there is an error message.

[silver moss]

I dont see anything wrong in the code

[vivid plaza]

Essentially, if one of the RayCasts hit something, it will show a Debug line in the SceneView and make the bot steer away from the obstacle.
When the car is approaching a wall, it works, which I can see due to the Debug line in the inspector and the car steering away.

[vivid plaza]

That makes us two. I'm gonna look if I find the problem.

Okay, I found the issue. I don't know how that makes sense though.

Before I fixed it, The collider of my car was made up of primitives (box colliders, capsule colliders etc.).
I changed it, so now the mesh of the car is the collider (using a mesh collider set to convex), and now it works.

Both the primitive and mesh collider used/use a Layer that's in the Layermask, which is why the solution is so senseless to me. However it works, so I won't complain.

[twin hill]

Hey everyone,

I’ve been running some performance tests in Unity and found something unexpected. I was comparing the performance of moving objects with colliders, and it turns out that moving a static collider (without a Rigidbody) is faster than moving an object with a kinematic Rigidbody (with Is Kinematic enabled).

However, according to Unity’s documentation Collider Overvie, static colliders shouldn’t be moved at runtime. Static colliders are meant to remain stationary, and Unity’s physics system is optimized for that.

Here’s the part from the docs:

“Static colliders: The GameObject has a collider but no Rigidbody. Static colliders are meant to remain immobile.”

Despite this, in my tests, moving a static collider directly via transform.position performed better than using Rigidbody.MovePosition() on a kinematic Rigidbody.

Has anyone encountered this before? Could this be because moving a static collider bypasses certain physics calculations that Unity normally applies to Rigidbody objects? Or am I missing some optimization considerations here?

Any thoughts would be appreciated!

Thanks! 🙂

[inner thistle]

The page you linked doesn't say that they should remain immobile

Apparently it was very expensive to move them in old versions but not anymore

[bleak umbra]

when you move a rigidbody, it would probably have to actively search for collisions after a move, where a static collider would only respond to the queries a moving rigidbody would make, so moving them does not involve a search for collisions where a rigidbody move/update would? I'd expect a change to static colliders only flag its BVH branch dirty and to update all rigidbodies for collisions that are inside in the next tick.

[normal wren]

I think not REALLY a physics thing, but:

I made a bullet system in which a bullet updates it's position along it's direction and incurs a gravity drop as it goes. I did all this in Update() * Time.deltaTime. In terms of gameplay, this all seemed sweet, moves nicely and I didn't notice any discrepancy in terms of bullet arc (from gravity).

However, I then wanted a trajectory line, and iterating through on a certain timestep in a loop in a single frame (to draw the whole arc) resulted in different results. I was wondering then, is this because update() is not actually stable and deltatime can be incorrect.... So, I started migrating my bullets sytem to use fixedupdate() instead even though they aren't rigidbodies or anything and currently it just seems worse in every way (erratic collisions, juddery updating, visuals way off). Should I be trying to move this system to fixedupdate? or am I barking up the wrong tree?

(I tried just putting the movement update into fixedupdate and lerping between in update and it's mostly broken)

[timid dove]

Yes this is why physics simulations use a fixed timestep

And what you are doing is a physics simulation

Make no mistake

There shouldn't be anything erratic though

That sounds like a bug in your code

Also yes you will get jittering unless you implement some kind of interpolation

(the physics engine does this with a setting on Rigidbody)

[normal wren]

yeah, i did somethig like transform.position = Vector3.Lerp(lastPosition, targetPosition, interpolationFactor); in update, with intention that visuals would happen there and updates in fixed... I'm wondering if I'm colliding with problems from pooling and stuff

[timid dove]

This is a problem if transform.position is also what your FixedUpdate is modifying

[normal wren]

(I guess I wasn't sure if this channel was just for havok or not)

yep I've been through a couple of methods, working from a currentposition value instead etc

but yeah everything seemed broken badly enouh after I started migrating that I wanted to check I was on the right track

[timid dove]

Also as for collisions if you're still using Unity's Colliders, then modifying the transform position directly will wreak havok with collisions

Realistically if you're using Colliders and moving them you should be using Rigidbody

You either need to fully embrace the physics engine or completely not use it

[normal wren]

so I'm using colliders to recognise collisions, the collisions themselves are raycasting from last frame to this frame, ie not rigidbody

(colliders are only on the "to be shot" objects, not on the bullets)

( i couldn't find a lightweight projectile weapon system that would do what I wanted so I made my own but regretting it now 😅

Also thinking it'd be better in some kind of burst jobbified system but I haven't got there yet)

it was working "perfectly" in update, 🤦‍♀️

[loud ridge]

can kinematic rigidbody on my limbs affect gravity of my other limbs, rest of the body?

[timid dove]

Wdym by "affect gravity"

You mean momentum/inertia?

[loud ridge]

I mean gravity

[timid dove]

What about this is "gravity"?

[loud ridge]

while all my limbs are dynamic, character falls down but when one of my limb is kinematic it doesnt fall down

I though it may be about limbs are not separate objects, I created them with sprite skin

[shrewd abyss]

yo, so i want my player sprite to have physics like this in the tail how can i do that (minut 38)
https://www.youtube.com/watch?v=V69G1sN0g_w

[loud ridge]

https://youtu.be/obYEeTEvS2M?si=4GHCHpQvxTOtR15s

search about things like this

https://youtube.com/shorts/fKK1Gl32oR8?si=OMo26AG9UPm3DGU0

https://youtu.be/6_lhTpmjHcA?si=KKVdf5QQqMTIDULo

[shrewd abyss]

tank you!

[round magnet]

Hey everyone,

I’m working on a simple 2D game in Unity with a stickman character, where each part of his body (legs, arms, head, torso) has its own rigidbody, allowing for physics-based interaction. I currently have a script that lets me click and drag the stickman around, and he moves and interacts with the physics.

For a while, I was trying to create animations for the stickman to get up and walk, but since the game is heavily physics-based, I thought it would be cool to make the walking physics-driven too, kind of like in games like Totally Accurate Battle Simulator or Stick It To The Stickman.

The only problem is… I’m not the best at coding. So, I’m posting here to ask for advice or ideas on how to approach physics-based walking. If anyone has any tips, knows of any relevant tutorials, or even feels like helping out with the code, that would be awesome.

Thanks a lot!

[royal willow]

are you looking for an active ragdoll?
https://www.youtube.com/watch?v=HF-cp6yW3Iw&t=523s&ab_channel=SergioAbreuGarcía

also I would suggest you !learn how to code with unity, and learn some C# as well https://dotnet.microsoft.com/en-us/learn/csharp

[flint portal]

:teacher: Unity Learn ↗

Over 750 hours of free live and on-demand learning content for all levels of experience!

[royal willow]

udemy also has a good one as well so I heard

[viral field]

Interesting. Free.
https://assetstore.unity.com/packages/tools/physics/betterphysics-selective-kinematics-244370

[royal willow]

was this not like 30 bucks or something?

[viral field]

Maybe.. seems to have been around for a while. Free now though

[round magnet]

Hi,

I am trying to make an active ragdoll script, I was looking at YouTube tutorials but they all don't work on what I'm trying to do. see the ragdoll will be on the floor, in any state. I've made a ActiveRagdoll script (attached) but for some reason it does not work at all. (attached videos are with and without it). Anyone wanna help? 🙏 🙂

thanks

https://www.codebin.cc/code/cm2lcgr680001lj02zdx8bn67:A7zGuxs82FFi3YTaByZKfa16gGfUjmDw8MnNVAH66vGR

https://drive.google.com/drive/folders/19lbekOIBc34sMBDdHFGBPSPNBJRbRne4?usp=sharing

[jovial carbon]

Noob question - first time doing physics ngl. I need to connect some non-kinematic rb to kinematic one using a joint. All of this feels really intuitive, I am just not sure about one thing:
Does it make any difference if I set joint component on kinematic/non-kinematic rb? I have some kinematic "grabber" controlled by mouse. It would be easier to just place it where raycast hits collider of non kinematic obj then do attachment instead of recalculating anchors

Ik there is "try out and see" thing, but having joint on grabber makes connected rb pivot snap to it, not sure if it's because of having joint on kinematic one or some other issue

[jovial carbon]

Ooooooohhhhh, that snapping would make sense ig

[ocean raft]

I have a ball thats constantly bouncing on a bounciness of 1. now i want the bounciness to slowly decrease overtime using C# script and then the ball should stop bouncing. How can i do that with C# script?

[inner thistle]

If you set the bounciness to any number below 1 (and above 0) then that's what it'll do

[frigid pier]

@stiff mulch Stop cross-posting. And add an actual question and proper description.

[ocean raft]

but i want the bounciness to decrease overtime

[royal willow]

then just reference it in a script and change it overtime
https://docs.unity3d.com/ScriptReference/Collider-material.html

[fast thistle]

Question: How might a game implement situations in which gameObjects that would normally collide suddenly behave differently? I'm particularly thinking of fighting games, where characters grab eachother, and the default interaction of their collision seems to go out the window, a la this.
I think, in the case of a 1v1 fighting game, you can probably just turn the colliders off and play some sort of animation, but I'm working on a game that will have more than two players, so I need to still account for collisions during these sorts of animations. My current thinking is to turn off the collider for the person getting grabbed, so that the grabbed person can move into the other's capsule collider space.

[timid dove]

Move the colliders to different layers

Or update the exclusion lists on them

[quasi meadow]

Good morning guys! i m some time testing hinge joint, i got them working but i want something and maybe im wrong on the way im trying to do it, i want like a wall where if i push from the left side rotate in this direction, but when i push in the right side do not the same rotation, well my english maybe isnt helping to much :L

[timid dove]

a picture or video might help?

[quasi meadow]

im able to make this hinge joint, in the corner the column and then push

But when i try to set the column in the middle and then push, isnt working in any direction, do you understand what im trying?

this is a video, i just modify the anchor and i was able to push in one direction, but what i need is when i press in the other corner, get the logical push direction but take a look

so... what i have to do? to get two hinge joint connected together?

[quasi meadow]

i need this with only rotation but if i set kinematic i cannot rotate, should i add code to use update and do not move?

[timid dove]

A simple hinge joint placed in the correct place will get what you want automatically

[quasi meadow]

im using a simple box, then i use scale to feel like a large block, with the pivot at the center, then if i use this setup and use connected anchor another body, it rotates only in one direction

[timid dove]

You'd have to show how you set up the joint.

Show the gizmos in scene view

Next to the colliders for everything etc

[dim fulcrum]

I have objects that I temporarily parent to my characters and set to kinematic=true and then set kinematic back false and unparent. Sometimes when they clip into geometry while kinematic they will violently fly somewhere. Is there a common way to limit this? maybe set the physics to somehow move the object to the closest spot it doesn't collide with anything, but then zero out the velocities?

[coral mango]

You shouldn't be scaling an object with a rigidbody on it in general

[quasi meadow]

Thanks

[coral mango]

Especially unevenly.

Best to have an unscaled parent object to put it on usually.

[mortal crane]

hello, i've started working on a new level for my game and i've been having this issue, why does the OnTriggerEnter(Collider other) event only seem to get triggered when in the scene view but not when controlling the character?

[light gate]

Show the collider config?

[mortal crane]

You mean the Inspector?

[light gate]

Yep

And the bounds of the collider as well

[light gate]

What layer is this object on? It’s cropped out at the top

[mortal crane]

Defualt Layer

[light gate]

So you have two colliders, one regular and one trigger. In game view, are you sure your player is actually able to enter the trigger collider? The mesh may be preventing your player from getting to the trigger collider

[mortal crane]

Yes, the collider is pushed to the front so the mesh is behind it to prevent situations in which the mesh would be blocking the collider

[light gate]

Have you tried disabling the mesh collider to confirm

[mortal crane]

There are no mesh colliders in the Player

[light gate]

No on the elevator

[mortal crane]

The CC is what prevents the Mesh from falling through the map

[mortal crane]

Oh

Give me a second

[mortal crane]

Ye, it's not the elevators fault. Since even when i jump out of the elevator and just try to touch the object from the outside with the elevator mesh colliders disabled, it still does not work

The only way i get it to work is like on the video, using transform in scene view

[light gate]

That scene view says the trigger works, but is not being reached in game view

[mortal crane]

When playing the Game in the Game tab when touching the other collider nothing happens, no response. When i go back to scene view while the test game is still running and use transform to put the player throught the other collider like on the video it works fine, The elevator animation plays and it Debugs that the Collider was Triggered

[light gate]

Yeah exactly. So when you can bend the rules and drag the player in scene view it works. Which is why I suggested there’s another collider getting in the way.

So you tried disabling the mesh collider on the elevator?

[mortal crane]

Yep

[mortal crane]

I also tested it by just spawning both the player and the collider i want to trigger outside the elevator without any other colliders nearby and doesnt work either

I tried OnColliderTriggerEnter, OnCollisionEnter, OnTriggerEnter and nothing seems to work

At this point i have no idea what can be causing the issue

Such a simple issue yet so hard to find an answer

Oh, i fixed it...

[light gate]

What was it

[mortal crane]

The Cube i wanted to trigger had both an Box Collider and a Mesh Collider, all it took was to remove the Mesh Collider

Welp

But thanks for trying to help anyways, appreciate the time :))

[brittle cargo]

<@&502884371011731486>

[wide nebula]

!ban 1136446860911972504 spam

[flint portal]

itsnotpres was banned.

[quasi meadow]

Good evening guys, i have a question, if i have a pose-t on my character, i want to use like a ragdoll but less expensive for my game, so what i mean is, can i add to each extremity like legs, arms, head, a simple box collider and then hinge joints to simulate like a ragdoll but basic one?

[royal willow]

you would need a rigidbody, a collider of your choice, then use joints to make it not bend in uncertain ways for each limb to simulate a ragdoll

just simple colliders wont do anything since they alone do not have physics

[quasi meadow]

but isnt working with hinge joint, should i use another more specific?

i was testing this, in the spine a rigidbody with one collider, and then in one arm a rigidbody with a capsule collider and one hinge joint connected with the spine, but when i test the arm still in same pose-t and the whole body falls to the floor

[royal willow]

here is the joints manual to check which joint will work for you but did you check if the arm rigidbody is kinematic? is it actually connected via joints?
https://docs.unity3d.com/Manual/Joints.html

also it looks like you either want a character joint or a configurable joint

[quasi meadow]

ok! i think i will do that thanks so much

[urban forge]

How do i make a grapple hook in unity

[eternal slate]

Can someone help me figure out why when I add a rigidbody to a prefab, unity 6 when I click play the editor does not go to play mode, like the game crashed?

its made up of child meshes each with their own collider.... nothing obvious stick out to me and i've been stuck on this for like 2 days

[timid dove]

Do you have your console window open?

[wary crater]

https://gyazo.com/aa33749236acc3f618a5d1a4e4f5948b.gif anyone know why this is happening?

this is my hierachy

and this is my rigidbody on the player

and there are box colliders on each foot (the spheres)

[coral mango]

What should be happening?

[wary crater]

so basically when I'm moving the player around a bunch it starts to just fall on the floor but what I want is for that to not happen

it's just spinning on the floor which is not what i want haha

[timid dove]

Constrain the rotation if you don't want it to tilt over

Tilting over like that is x and z axis rotation

[wary crater]

I realised that the rigidbody is in the Player object and the thing that is being rotated is in the PlayerModel

So when I constrained the x and z axis for the Player it still means that PlayerModel can fall on the floor

But since my movement script relies on the Player object to have the children setup like that is there a way to still prevent it?

[timid dove]

The only thing that is physically simulated is the Rigidbody

So no that description doesn't make sense

Unless you have more than one Rigidbody

Or if your script is the thing rotating it

In which case you just need to fix your code

[fleet owl]

I'm stuck with a physics thing in unity, basically trying to have a bus that drives itself and a FirstPerson character that can sit in it. The bus driving physics/code works perfectly well but when the player sits inside the bus he gets dragged to the back whereas the behaviour I want is for the player to stick to their position and be able to move freely (just like how humans work inside buses)

So far I've tried:
Parenting the player transform to the bus transform using OnTriggerEnter, doesn't work
Using physic materials should work but for some reason isn't working at all

I am open to all ideas and trying them out also can share more details

[timid dove]

Your player movement code is very relevant to this question

[fleet owl]

haha i was pretty much reading your prev messages about this, let me share my player code pretty straight forward actually

https://pastebin.com/7b1TLG8V

Not the best code probably but the only place where the player handles movement is MovePlayer() and this part:

void MovePlayer()
    {
        // Cast a ray downward from the player's position to check if they are grounded
        isGrounded = Physics.Raycast(transform.position, Vector3.down, out RaycastHit hitInfo, groundDistance, groundMask);
 
        float moveX = Input.GetAxis("Horizontal");
        float moveZ = Input.GetAxis("Vertical");
 
        Vector3 move = transform.right * moveX + transform.forward * moveZ;
        Vector3 moveVelocity = move * moveSpeed;
        rb.linearVelocity = new Vector3(moveVelocity.x, rb.linearVelocity.y, moveVelocity.z);
 
        // Jump
        if (Input.GetKeyDown(KeyCode.Space) && isGrounded)
        {
            rb.linearVelocity = new Vector3(rb.linearVelocity.x, Mathf.Sqrt(jumpHeight * -2f * gravity), rb.linearVelocity.z);
        }
    }

I feel the bigger issue here is the bus moving and there being no "friction" between the player rb and the bus rb.

[timid dove]

As I guessed, you're setting velocity directly here

What do you suppose will happen when this code sets velocity to 0 and the bus moves

[fleet owl]

oh!

tbvh i thought i was doing that but then i looked at the code and missed it my bad

switching to addForce

I am using other than that change I can just add a OnTriggerEnter to parent the player to the bus when it's inside?

IT WORKS THANKS @timid dove 😄

[timid dove]

Parenting won't do anything for dynamic Rigidbodies

[fleet owl]

oh? also how should I use the addForce since it does a very "non-instant" movement slowly adding force. is there maybe a script somewhere i could learn from?

[low breach]

using add force and experimenting with different force modes will help

[tribal badge]

Hey everyone, I'm doing something wrong with my raycast and could use a bit of help.

I have two colliders attached to a gameobject.
Collider A uses include layer Projectile. Collider B uses include layer Entity.

When I cast a ray towards them I expect the collider A to be hit but the other collider is hit instead.

Physics.Raycast(ray, out var hit, 1000, ~(1 << LayerMask.NameToLayer("Projectile"))

Do collider layer overrides or raycast layermasks work differently than I expect?

[timid dove]

Layer overrides are irrelevant for Raycasts

Also you should use GetMask to make your layer mask

The thing that matters for Raycasts is the layer the GameObject is on. Since they're both on the same GameObject, they both have the same layer

[tribal badge]

Okay I was afraid this would be the case. Thank you @timid dove!

[iron wing]

Hey everyone! Im currently running into an issue with character joints.
I have a ragdoll character that's parented to another object that can move around
(More simply said, the player can carry ragdolls on his shoulder)
The problem now, the legs are very jittery. The rest of the body is as well, but the legs only matter because in FPS view you can't see the body & arms.

I saw that "enabling projection" works, yet, it doesn't seem to work for me. I tried to change the value as well but that doesn't seem to do anything.

I can send a video of the problem if needed

[timid dove]

Moving a Rigidbody via parenting it bypasses the physics engine and is going to cause all sorts of anomalous motion

You'll want to move the object via setting it's velocity or attaching it with joints

Or with e.g. MovePosition in FixedUpdate if it's kinematic

[iron wing]

Oh thanks, which joint should I be using?

[timid dove]

Up to you

Any you think suits how you want the thing held

[iron wing]

Well, I want it to be fixed, behaving as if it was parented

[timid dove]

FixedJoint then?

[iron wing]

oh, logical

I'll try that! Thank you

[tiny relic]

Is there any way to override the standard unity collision resolution function?

A lot of other engines handle let you dig into it by default. Having worked in unity a long time, I haven't seen any way to do it, nor any reason not to have it.

PhysicsMaterial is incredibly limited in what it can do and doesn't really solve the core problem

[hollow echo]

Like this? https://docs.unity3d.com/ScriptReference/Physics.ContactModifyEvent.html

[tiny relic]

Potentially might be what I'm looking for

I'll need to look into it a bit

[supple lantern]

Hi guys I am using the wheel collider with default settings other than the radius (made it fit the model), have a rigibody with mass of 1500 when I start the game scene my car turns into a monster truck.

but when I reset my car to a respawn location it fixes its self to what I would expect. second image. anyone had this issue before ?

or any suggestions.

[fleet owl]

I am new to this but I had a similar problem recently, is it possible that you have colliders on the wheel meshes of your car? (This might not be the solution but I went with something similar recently so just trying to help :D)

[urban forge]

Is there any good source to learn math and physics for game dev

[supple lantern]

Hi mate nah no colliders on my wheel meshes just the car, not sure what caused the issue but I revered back to a version of the project and its not broken in there, so I must have changed something in my car control script, woo for version control just need to use it more so I dont lose couple hours work haha.

[crude kite]

Note that by default, the friction and collision resolution uses a fake model based on the number of contact points, producing unrealistic results. This is the only combo in the Physics settings that calculates friction in a physically realistic way:

More info and additional links in the replies:
https://x.com/VehiclePhysics/status/1668614413471956992

Vehicle Physics (@VehiclePhysics) on X

#unitytips THIS is the ONLY settings combo that provides physically realistic collisions and frictions in Unity: Patch Friction Type + Improved Patch Friction.

Friction worked realistically up to Unity 4. From Unity 5 to Unity 2020 it was essentially trial & error. This combo in

Twitter · Jun 13, 2023, 1:40 PM

With the above settings, you can configure the PhysicsMaterial using real-world data and expect mostly realistic results.

[narrow pier]

Hello! Are there any resources to learn what exactly happens on PxScene simulation (what are the steps and in what order they are executed)? I didn't find anything specific in PhysX documentation.

[tribal badge]

Hello everyone, how do I change the direction in which a flat meshcollider surface collides with objects?
I tried inverting the normals but the collisions are still happening in the same direction.

[timid dove]

What do you mean by the direction in which it collides?

[tribal badge]

When I ray cast on it for example, the ray only collides with it from one side

[timid dove]

yes because a single triangle of geometry only has one side. You will need to make an actual 3D object with "thickness" if you want double sided raycasts.

but if it's flat, why use a MeshCollider at all? YOu can do Plane.Raycast

what's the use case/gameplay scenario here?

[tribal badge]

Ah so the normal of the trianges don't make any difference?

[timid dove]

sure they do, but a MeshCollider creates its own internal simplified mesh from your mesh.

it's only going to have a single valid side

what are you trying to achieve here

[tribal badge]

I want to detect whether I hit a chainlink fence with a ray cast bullet. The chainlink fence has no thickness.

[fleet owl]

haha yes, i spent around 2hours extra because i didnt have version control but not anymore

[timid dove]

simplest thing is to use a BoxCollider

[tribal badge]

A box collider wouldn't fit because the fence has rounded corners. But I set the mesh collider to convex now and it seems to work fine.
Thanks again, I didn't know that Unity's physics engine has a seperate representation of its mesh colliders irrespective of MeshCollider.sharedMesh.normals.

[frosty eagle]

Is there anything that needs changing in regards to physics when updating from 2022.3.44f1 to Unity 6?

We are seeing a huge CPU draw from the physics engine after updating

2022.3.44f1

Unity 6

It's the same scene on both

[quiet mauve]

Hey guys
I'm working on a Unity project where I'm implementing a drag-and-drop system for placing furniture in a scene. I have a FurnitureDragHandler script that allows users to drag furniture from a UI menu into the scene, and it works fine for initial placement.

However, once the furniture is placed, I want to enable the ability to drag it again using a separate DraggableObject script. I added the DraggableObject component to the furniture after placement, but I cannot seem to drag the placed furniture afterward.

[timid dove]

I cannot seem to drag the placed furniture afterward.

why not? How is it supposed to work? What debugging steps have you taken?

[uncut anvil]

Do you guys know how to maintain velocity of a rigidbody on letting go of LMB when I'm using the below to move it around (on holding LMB)

void MoveObject()
{
Vector3 targetPosition = mesh.position + mesh.forward * detectionRange;

// Use Rigidbody to move the object
objectGrabbed.MovePosition(Vector3.Lerp(objectGrabbed.position, targetPosition, objectMoveSpeed * Time.deltaTime));

}

[timid dove]

how about just using velocity instead of MovePosition

MovePosition won't respect collisions anyway

or, when you release it, you can apply a velocity based on how much this code would have moved it.

[uncut anvil]

Do you have a good example of this? Sounds like a good idea

[timid dove]

e.g.

Vector3 targetPosition = mesh.position + mesh.forward * detectionRange;
Vector3 expectedPosition = Vector3.Lerp(objectGrabbed.position, targetPosition, objectMoveSpeed * Time.deltaTime);
Vector3 velocity = (expectedPosition - objectGrabbed.position) / Time.fixedDeltaTime;```

(when releasing)

[uncut anvil]

So which velocity would you apply this to then? Since rigidbody.velocity isn't a thing anymore?

[timid dove]

rigidbody.velocity is absolutely a thing

[uncut anvil]

I only see angular and linear velocity?

Where, senpai?!

[timid dove]

I assumed you meant 3D

in 2D it's now called linearVelocity, yes.

[uncut anvil]

No I'm in 3D

[timid dove]

then it should be velocity unless they renamed it there as well and I'm mistaken

I guiess maybe they renamed it everywhere

either way it's the same thing.

[uncut anvil]

Haha so does it matter which one I use?

[unique cave]

Seems to be renamed to linearVelocity (on unity 6), sounds kinda weird rename to me

[uncut anvil]

Yeah it does. Ok I'll try that 🙂

[wind quail]

Can anyone suggests how to make a proper collider for my car? i currently just use a box collider but because of the lack of smoothness whenever i go over the tiniest of bumps the car colliders and loses a lot of speed which just looks and feels very horrible

[royal willow]

you can use a convex mesh collider for the body or use primitives to make a custom one

[cerulean creek]

wow that Disable All button on the physics grid is pure evil design. took a chance thinking it must just disable al highlighted rows/columns, nope, disabled every checkmark. why would anyone want that? Of course Undo doesnt work and I even quit the project without saving and re-opened it, but somehow it's all still blank squares

[timid dove]

Easy to revert with version control

[brave rapids]

You can add four separate wheel 🛞 colliders on car wheels, and a separate box collider on car body

[ashen swift]

hi i have a rigidbody2d that moves to the right on its own

i commented out the moveposition script

so theres no code affecting the movement/physics

[ashen swift]

ok so i found that "simulated" in rigidbody is making my dynamic character move by itself

why is this?

[timid dove]

Gravity

Or something is pushing it

Or some code is moving it

There are sometimes some weird configurations with joints or just weird object shapes that can create a phantom force in one direction just due to inaccuracies in the physics simulation too

[ashen swift]

now it doesnt move

even with my moveposition code

is that because its not simulated anymore?

[timid dove]

yes

If you want it to be an actively simulated physics object, simulated needs to be on

[ashen swift]

i give up

just cant win

im gonna rebuild everything

[timid dove]

What are you trying to do

and what's your current setup

[ashen swift]

im just trying to make my guy move with the joystick

it used to work but i made it kinematic and not dynamic

which was a huge mistake

[timid dove]

"just make my guy move" is pretty vague.

there are many different ways things can move

You'd have to describe what kind of movement you are looking for

[ashen swift]

im uaing moveposition

for rigidbody2d

[timid dove]

probably not a great idea unless you don't care about collisions

setting velocity would be better usually.

but again

you have to explain the style of movement you want.

[ashen swift]

idc what style

i just want it to move and collide

[timid dove]

wanting it to collide is important information

that's what I'm saying

you need to explain stuff like that

[ashen swift]

ic

ok sorry

[timid dove]

Setting velocity will probably be the simplest.

[ashen swift]

whats the method

[timid dove]

but like... do you need gravity? etc. There are so many little details

[ashen swift]

no gravity

it's a 2d sidescroller

and i need clamps

[timid dove]

something like:

float horizontalInput = Input.GetAxisRaw("Horizontal");
myRb.linearVelocityX = horizontalInput * moveSpeed;```

clamps?

wdym by clamps

[ashen swift]

so that it doesnt go out of bounds

[timid dove]

Use colliders

[ashen swift]

i rather use clamps

[timid dove]

why

[ashen swift]

is that not possible with linearvelocityx

[timid dove]

that's what colliders are made for

[timid dove]

You would be bypassing the physics engine which is a bad idea

it will cause issues

[ashen swift]

ic

ok then colliders it is

ty sir

[hot edge]

Sry miss click

[ashen swift]

Rigidbody2D' does not contain a definition for 'linearVelocityX' and no accessible extension method 'linearVelocityX' accepting a first argument of type 'Rigidbody2D' could be found (are you missing a using directive or an assembly reference?)

[twin nebula]

Is there a method I should use to move rigidbodies that actually works well with interpolation? If I have any sort of interpolation (interpolate extrapolate) on my rigidbody and set the position somewhere in FixedUpdate it causes one frame of jitter

Tried MovePosition and just directly setting the rigidbody component's position along with the transform's position

This is an issue I've had with interpolation for a while and it's extremely annoying. It seems like trying to halt or teleport a rigidbody in any way causes jitter (for example interpolate made the rigidbody move ahead for a frame and then go to where it should've been because I set the velocity to zero)

[unique cave]

did you type .linearVelocity.x or linearVelocityX? LinearVelocity is a Vector2, there's no X and Y properties separately

[ashen swift]

in the properties list of rigidbody2d it lists linearVelocityX as a property

this is for 2d

[unique cave]

That I figured but .velocity used to be the only way on 2D too. You are right though, they seem to have added that to Unity 6, are you using Unity 6 or older?

[ashen swift]

im looking at it right now

it's right after linearVelocity

unity 6

but not the most recent

guess i should update

[unique cave]

Could you share your code here?

it should be there starting from Unity 6000.0

[ashen swift]

oops

how do i close code tag

gameObject.GetComponent<Rigidbody2D>().linearVelocityX = Joystick.GetComponent<UltimateJoystick>().GetHorizontalAxis() 
* Time.deltaTime * 3f;

[unique cave]

I don't see a problem here, could potentially be a problem with your IDE not communicating properly with your unity version but I'd probably just try to good old .velocity way https://discussions.unity.com/t/how-to-set-velocity-of-only-one-axis/830584

[plush plinth]

im using my rigidbody like this :
rb.MovePosition(rb.position + dir * movementSpeed * currentRunSpeed * Time.fixedDeltaTime);
The problem is, when it comes in contact with stationary box colliders, it starts spinning and drifting. Any way to disable any backwards force towards the rigidbody?

like for it to be not affected at all. The bouncines on physics material is set to 0

[unique cave]

Why are you not using the velocity/angular velocity?

[ashen swift]

so i updated my unity version

it plays but it's still moving on its own

Y movement is not working

[unique cave]

what you mean by that?

[ashen swift]

it's not responding to y axis of joystick

and it's still flying off to the right by itself

[plush plinth]

should I? movePosition does the job

I don't need velocity

[unique cave]

What is it that you are doing? A character?

[plush plinth]

yeah, it's just a character moving in 2d space.

[unique cave]

do you use 2D or 3D physics engine

[inner thistle]

Well it's not doing the job if it doesn't behave the way you want

[plush plinth]

3d in 2d space

[inner thistle]

The problem with MovePosition is that it forces (no pun intended) the rigidbody to the new position so it's very hard to prevent it from bouncing back if it goes inside a collider

[plush plinth]

I don't think it's tied to the movePosition, all I really need is a way to disable backwards force towards the rigidbody, when colliding

ah

[unique cave]

MovePosition isn't really any better than transform.position for non-kinematic bodies and therefore other methods (namely velocity and forces) are usually preferred

[plush plinth]

alright, got it

thanks

[ashen swift]

whyyyy is my guy moving on its own

[unique cave]

Make sure your joystick isn't giving non 0 input by default

If it does, add bit of dead zone to not care of little inputs

or try to recalibrate the device somehow. Other players might find the same issue though so dead zone setting might be useful for others too

[ashen swift]

oh dead zone

i think i changed that value

ill check tmrw

[grave spindle]

why are ragdoll physics that much unstable ?

i tried using projection or better rigibody collision detection but its still that bad

[timid dove]

usually it means collisions between interconnected bones.

make sure collision is disabled on all the joints

and that none of the other bones are overlapping each other

[grave spindle]

joints collisions are disabled

[grave spindle]

for this part you want that the bones ignore each other ?

(for the capsule colliders)

tried both are its still very unstable

bones doesnt collide each other & joints doesnt have collision & have projection enabled

looks like the biggest issue happens when the ragdoll hits the ground

[timid dove]

what collision detection mode are you using

[grave spindle]

tried default and continuous

on the bones

[grave spindle]

yeah tried a lot of stuff still weird

reducing fixed timestep and increasing solver iteration mosty fixed the issues

[brittle crown]

How can i increase the effort of the Physics Engine? my solver iterations are allready at the highest and theres still alot of bugs. These are my current Physics Settings:

[loud ridge]

I watched some tutorials to make my ragdoll character with inverse kinematic arms to grab objects. This is my code https://paste.ofcode.org/8LiM3cwQthT8X3GmiLXffD. I used trigger enter because using my hands as a collider broke some things.

I made debug.break(); when it enters trigger and checked the fixed joint I create with script and anchor looked normal.
So I cant understand why joints break.

[timid dove]

Reduce fixed timestep

[brittle crown]

Sure

[brittle crown]

What value would you recommend? its at 0.02 right now.

[lost current]

hey fellas, I'm curious. I want to give the player the ability to walk on walls & the ceiling when they reach a certain velocity, I know that I need to check if the player is touching the wall at a certain point & flip them but I'm not sure how it'd be the best way to do it

uh, would love some help in that regard :D

[royal willow]

you could use raycasts to detect if you are near a wall, then just find out if the velocity is over a certain threshold, then flip if both are true

[lost current]

true, but how would one handle the physics aspect?

As I am using a player controller script with a RigidBody2D component to handle the physics side (AKA, I'm not using custom physics or anything like that)

[royal willow]

are you asking how you would flip the player?

just invert the gravity then flip the sprites

[lost current]

there seems to be a bit of a confusion here

[royal willow]

specify what you mean by to handle the physics side

[lost current]

I'm asking how to do this

& idk how one can have the player stick to the wall & move alongside it like it's a normal surface

cause flipping it to stick to the roof is as easy as multiplying the rigidbody gravity value with -1

to a wall tho? I'm unsure how to do that

[royal willow]

you would rotate the player with the rotation of the normals you are standing on and to stick the player to the wall you can disable gravity and make your own and just change the direction of it with the normals as well

this is all theory of course

[lost current]

fair

[royal willow]

but in theory it should work

to add on if you do rotate your player with the normals, to jump or move you would have to use the local vectors instead of global vectors

[timid dove]

A smaller one

[sturdy zinc]

Edit: Issue is resolved. Found this code buried and I don't even remember writing it 😄

// Cancel the angular velocity on the z-axis of the RigidBody to get rid of unwanted roll
if (!_oneWheelGrounded)
{
    var rbAngularVelocity = transform.InverseTransformVector(_rigidbody.angularVelocity);
    rbAngularVelocity.z = 0f;
    _rigidbody.angularVelocity = transform.TransformVector(rbAngularVelocity);
}

---

Hi there, hoping someone can help me out with adding torque to a RigidBody with inertia. Essentially, I am applying torque on all axes based on player input. Both yaw (y-axis) and pitch (x-axis) feel like they have some inertia behind them as when the input given is 0, the inertia slowly dissipates over a couple of seconds which is the behavior that I am looking for. However, the roll (z-axis) torque doesn't seem to have any inertia behind it and requires a lot more torque to get spinning at a similar rate as the others. Once input stops, the RigidBody stops spinning immediately.
I am not really sure what could be causing this as I have never had this issue before. I did have to manually set the inertia tensor to 200 on the x, y, and z axes because the automatic setting was causing my motorcycle to slide.
I am using the latest 2022 LTS - 2022.3.51f1
Here is a quick snippet of how I am applying the torque to the RigidBody:

private void ApplyTorque()
{
    // Return if no RigidBody
    if(!_rigidbody) return;
    // Return if grounded
    if(_oneWheelGrounded) return;
    
    // Apply axes torque in the air
    var yawTorque = _yawTorque * _steeringInput;
    var pitchTorque = _pitchTorque * _leanLongitudeInput;
    var rollTorque = _rollTorque * -_leanLatitudeInput;
    
    _rigidbody.AddRelativeTorque(new Vector3(pitchTorque, yawTorque, rollTorque), _torqueForceMode); // Force mode is set to "Acceleration", but the issue persists with all force modes
}

And here is a short video demonstrating the issue that I am having and how I have things set up: https://www.youtube.com/watch?v=V9ztjSJCQkI

[twin nebula]

Bumping this

[narrow pier]

There is no way of performing interpolation of rigidbody's visual transform without one frame delay

[twin nebula]

Aw dang

[narrow pier]

There are a couple of ways you can teleport RB immediately with it's visual Transform.
You can set new position of Transform(!) component and call Physics.SyncTransforms(), this will bypass interpolation for a frame.

Another way I'm not confident about is to disable interpolation before teleportation and reenable it later on at least after one frame (using some Await/Async or any other preferred way)

[loud ridge]

I watched some tutorials to make my ragdoll character with inverse kinematic arms to grab objects. This is my code https://paste.ofcode.org/8LiM3cwQthT8X3GmiLXffD. I used trigger enter because using my hands as a collider broke some things.

I made debug.break(); when it enters trigger and checked the fixed joint I create with script and anchor looked normal.
So I cant understand why joints break.

[coral mango]

Looks like you are likely creating a state the physics can't easily resolve somehow...

[silver moss]

Are you making sure that it does not add the fixed joint multiple times?

It also looks like your bones/joints are parented to each other. In my experience it is best to keep them as siblings instead

Avoid parenting rigidbodies to each other

[sage palm]

How can you eliminate the jitter/jiggling when many rigidbodies are touching eachother, like say a pile of coins. It takes a long time for the objects to settle and stop the jittering. Is there a way to have this fine physics movement stop at a certain threshold?

[median plover]

I'm trying to make my vroid model and the hair has me frustrated. I think this is a physic issue? im not sure, im not really a big unity user unless it comes to my models. Does anyone know how to adjust the hair so it's not floating? I feel like its getting stuck on a collider but I'm not sure. I hope these pictures also help with what im trying to ask

[coral mango]

Vroid hair doesn't use the unity physics system, does it?

[median plover]

im not sure but the hair that i am using is for made for vrchat but i ended up figuring it out in the end, took a really long time to get

[muted rivet]

sorry for Necro reply

adding consistent acceleration to counteract gravity when on-wall and adding same force towards it should do the trick, it would be sorta modified gravity direction

[muted rivet]

there should be great addon for vrm in blender, it would allow for gltf export+colliders generation and everything, something with kittens in name, memory lost the exact phrasing sorry.

[muted rivet]

physics sleep threshold in projects physics setting. that and physics timesteps.

sleep threshold=at what point body will be stationary
timestep=how much frames physics have per game frame.

but beware that constant contacts are notoriously hard for physics enginies, its one of stress tests so i would suggest trying to minimize it as it can...explode

[sage palm]

I'm experimenting with the unity physics so I made a little coin pusher sort of thing and it's main feature is stacks of coins that then react when other coins are pushed into them.

How can I minimize the constant contacts in a case like this? Its core to the gameplay of something like a coin pusher.

[muted rivet]

hm, in this case increasing physics samples and sleep threshold(so bodies are considered static earlier) is a go

[tawny kernel]

for some reason unity is lagging incredibly badly (skipping frames)

profiler looks like that

all im doing is rendering a few balls with a spinner

im also using a render texture for some custom post processing effects

rest also look like this

nvm i figured that it was the 8x antialiasing on the render texture

with that color format

[muted rivet]

@tawny kernel also try to minimise rigidbody overlap or make them ignore eachother with layer overrides. them being forced to overlap might just be one of major additions

[tawny kernel]

yeah no it actually just ended up being purely rendering

i guess it cant do antialiasing on 1024x1024

[loud ridge]

but inverse kinematics mess up when I dont make upper arm parent of my lower arm

[silver moss]

What are you using for IK?

The IK should not directly rotate the rigidbodies, it should modify the joints motors/target rotations

Are you even using joints for the ragdoll?

[viral beacon]

I am having an issue where my trail makes it appear as though the bullet is spawning in an unusual place when firing while moving. Is there a way to make the trail draw relative to the weapon? I am using a rigidbody projectile for bullets.

[timid dove]

You'd have to show how and where you're spawning the trail as it is

[young gate]

Anyone know any good writeups about articulations by someone who's made lots of use of them? I'm not after how to do X but rather want insight on the various pitfalls / sacrifices / work arounds someone might run into when making full use of Articulationbodies in Unity

There's plenty of demos and instructions for single uses of them but I'm after the sort of knowledge you'd pick up after trying to get articulations to play nice and interact with each other in actual gameplay, the weird quirks and things to avoid

Perfect example of this sort of knowledge is Edys tweet about how drag is related to FixedTime rather than independent of it, knowing those sorts of quirks instead of slowly discovering them after wasted hours would be great

[young gate]

I guess I'm asking "where are the ghosts hiding in unity physics"

[young gate]

Oh you're in here even, Thanks for all the information you've put out there I really appreciate it

If I find a detailed authoritative physics post when trying to debug something, there's an 80% chance it's under your name

[zealous pawn]

Hello, I have a question that's half a blender question and half a Unity question, and maybe not at all a physics question but this seems like the best place to ask. I have a rigged landing gear system in Blender. I want this landing gear to work in Unity as well, but the armature isn't working in Unity like it is in Blender.
I don't want to make animations for the landing gear, instead I want it to be physics-based and react to the weight of the weight of the airplane.
I'm looking for any tips/help- do I need to do something in Blender to import the armature correctly? Or do I need to set up physics joints in Unity? Or both?

[timid dove]

You need inverse Kinematics

[zealous pawn]

I have inverse kinematics in Blender, is there a reason it didn't get imported to Unity? Or do I have to set up inverse kinematics independently in Unity?

[timid dove]

The latter

[zealous pawn]

Thank you.

[full peak]

Heya! I'm looking for a dynamic cable solution that can retain the underlying shape of the cable.
I can find lots of packages that seem to do B, where a cable is simulated between two points.
But what I'm after is A: perhaps something based on a bezier spline that will aim to retain that shape while still having some give & bounce.
Does anyone know of something on the asset store that would do that?
(I can see lots of cable simulation packages, but I'm hoping I won't have to try each one to see if it does this!)

[indigo echo]

Hi! I'm have a problem over here with my character. Basically what i'm trying to do it's a character that can run on walls, and to achieve that it rotates it's up direction to match the normal of the surface it's running on and if it's touching multiple surfaces then rotate it to the average normal of them. But i'm having a problem with the collision detection in situations like in the video, where it's the edge of a ramp. It detects multiple surfaces and using the average of their normals for it's up direction, even tho it's only touching one surface. This only happens when using a capsule collider, because i tried with a sphere collider and it worked like i expected.

It should be something like this (i'm using a sphere collider) (the blue line it's the normal it's using for it's up direction)

[light gate]

Maybe Full Rig. https://assetstore.unity.com/packages/tools/modeling/full-rig-250271#description

[unique cave]

How are you getting the normals and their averages? Physics? Raycasts?

[indigo echo]

both collision enter and collision stay

then they both call a function that calculates the dot product between the collision's normal and the player's (to decide if it's too steep)

[unique cave]

I would generally prefer raycasts (SphereCast in your case) in this kind of cases for best quality normals

[indigo echo]

i tried that, but doesn't work with non-convex surfaces and i want it to work with them just to skip a buch of work when making levels

[unique cave]

What you mean "doesn't work"? I'm pretty sure casts work with any type of colliders

[indigo echo]

i checked the documentation and you're right. I remember i used a method that doesn't work with non-convex colliders. Maybe i confused that with sphere cast

i'll give it a shot to see if it works, thanks for helping!

[unique cave]

SphereCast should work too. The crucial difference between RayCast and SphereCast in this case would be that RayCast gives the actual surface normal at the hit point while SphereCast would give the normal along which a ball would bounce if it was thrown at the path of the cast. At mesh corners RayCast gives either faces normal while SphereCast doesn't which would allow for more smooth rotations which in your case might be desirable

[indigo echo]

Update: I used SphereCastNonAlloc and it worked, but now it will only detect one hit per element, making that if there's two hits with the same element then it can't use the average normal of them (first two examples). Only when it's two hits on two different elements (last two examples) it can use their average normal.

[silver moss]

How are you doing it, show your code
SphereCastNonAlloc specifically lets you get multiple hits

You could just iterate all the hits and add their normals together and then normalize the total if needed

Check out !code

[flint portal]

Posting code

📃 Large Code Blocks

Use links to services like:
https://gdl.space/, https://paste.ofcode.org/, https://hatebin.com/, https://paste.myst.rs/, https://hastebin.com/

📃 Inline Code

Surround code with three backquotes. Not quotation marks.
To format as C#, add cs to the first line:
```cs
// Your code here
```
Add a comment with a line number if there is an error message.

[silver moss]

Specifically the "Inline Code"

[indigo echo]

oh, thanks!

void DetectSurfaces(){
  Vector3 sphereOrigin = RB.transform.position + RB.transform.up * 0.5f;
  //RB it's on the lower part of the collider, this puts the origin at it's center

  RaycastHit[] hits = new RaycastHit[10];
  Physics.SphereCastNonAlloc(sphereOrigin, 0.505f, -RB.transform.up, hits, 0.5f, layerMask, QueryTriggerInteraction.Ignore);
  //Capsule collider height is 1 and radius is 0.5

  foreach (RaycastHit hit in hits){
    if (Vector3.Dot(hit.normal, RBNormal) >= minGroundDotProduct){
      groundContactCount += 1;
      avgNormal += hit.normal;
    }
    //Uses avgNormal.normalized for RB.trasform.up
  }
}

@silver moss here it is

[silver moss]

SphereCastNonAlloc returns an int.
That int is the number of hits that were written to the hits array

So you should do ```cs
int hitCount = Physics.SphereCastNonAlloc...

for(int i = 0; i < hitCount; i++)
{
var hit = hits[i];
...```

Currently you are using foreach which loops over all the hits, even the empty/unused ones

[indigo echo]

alright, let me change it quick

[silver moss]

As an extra optimization, you can make hits a static array so it can be reused. Declare it in the class:cs static RaycastHit[] hits = new RaycastHit[10];
Otherwise using NonAlloc doesn't make sense - you are currently allocating a new array each time

Allocations = More work for the garbage collector = Worse performance

[indigo echo]

so that's how it works, i'm new to arrays an c# in general

thanks for the tip!

wait, i'm getting error CS0106 "The modifier is not valid for this item"

nvm, just put the declaration of the array outside the function

[silver moss]

Yeah that's what I mean with "declare it in the class"

[indigo echo]

btw, it's still happening

[silver moss]

Show updated code?

[indigo echo]

the spherecast it's picking only one hit

on it

static readonly RaycastHit[] hits = new RaycastHit[10];

void DetectSurfaces(){
  Vector3 sphereOrigin = RB.transform.position + RB.transform.up * 0.5f;

  int hitCount = Physics.SphereCastNonAlloc(sphereOrigin, 0.505f, -RB.transform.up, hits, 0.5f, layerMask, QueryTriggerInteraction.Ignore);

  for (int i = 0; i < hitCount; i++){
  if (Vector3.Dot(hits[i].normal, RBNormal) >= minGroundDotProduct){
    groundContactCount += 1;
    avgNormal += hits[i].normal;
  }
}

[silver moss]

Start by logging the hit count with Debug.Log

Maybe the other object fails this check?cs if (Vector3.Dot(hits[i].normal, RBNormal) >= minGroundDotProduct)

[indigo echo]

was already doing that, it says only 1 hit

[silver moss]

Could be incorrect layers

And/or an invalid layermask.. How are you defining the layerMask? Where does it come from

[indigo echo]

all default layers. The examples on the video are ramps flat enough to be true on that check

[silver moss]

Oh and make sure that the SphereCast doesn't start inside a collider. It won't detect colliders that it initially overlaps with

Make it a bit smaller than the capsule and/or move it up a bit

[indigo echo]

that's is why i started it on the middle of the character

[silver moss]

Looks like your radius is 0.5f, that means a sphere 1 unit wide

[indigo echo]

i mean the origin

[silver moss]

Is your character 1 unit wide?

[indigo echo]

yeah

i added a little bit of skin width in the radius of the spherecast to allow some wiggle room

[silver moss]

You made it a bit smaller right?

[indigo echo]

the other way around, i made the radius of the SC larger

[silver moss]

Nah make it smaller

[silver moss]

This is important^

If the sphere is larger than the character's collider, then it has a chance of already overlapping with a collider and will fail to hit it

[indigo echo]

i forgot to mention, the capsule collider of the character has it's layer set to ignore raycast

[silver moss]

Yeah that's good, but doesn't change what I said

[indigo echo]

made the SC smaller, now it doesn't detect anything

[silver moss]

Make sure to account for that in your max distance

Which was .505

You can use gizmos to visualize the sphere:cs void OnDrawGizmos() { // Calculate sphereOrigin here again Gizmos.color = Color.yellow; Gizmos.DrawWireSphere(sphereOrigin, radius); }

[indigo echo]

now it can detect flat surfaces but not ramps

[indigo echo]

that's helpful, thanks

[silver moss]

Actually unity has physics query visualization too

https://docs.unity3d.com/Manual/PhysicsDebugVisualization.html#physics-debug-queries

That's more helpful

So you can see exactly how your spherecast is aligned

[indigo echo]

@silver moss whyyy

it's detecting two hits, but only using one and saying it's only detecting one

[silver moss]

What is your debug.log? Are you just logging groundContactCount?

[indigo echo]

ok, something strange it's happening. I tested using the case where there's two separate elements, and when the query says there's two hits, the SC says there's only one, but if i keep going towards the middle point between the two ramps then then the SC says there's two hits and uses the average of them

[silver moss]

I'm pretty sure that this:cs (Vector3.Dot(hits[i].normal, RBNormal) >= minGroundDotProduct) Should be:cs (Vector3.Dot(hits[i].normal, Vector3.up) >= minGroundDotProduct)

[indigo echo]

this is when the character it's not in the exact middle

[silver moss]

Comparing with RBNormal doesn't make sense to me

[indigo echo]

this is when it is

[indigo echo]

now that i think about it your'e right, not in comparing it to Vector3.up but in that it doesn't make sense to use RBnormal

i should be using RB.transform.up

[silver moss]

Well, i assumed that RBNormal was the transform up

What is your minGroundDotProduct set to?

[indigo echo]

RBNormal is what i use to set the transform.up, not the transform.up itself

[indigo echo]

80 degrees, which is 0.17