⚛️┃physics

[tawdry wave]

And to align them perfectly takes time too

So that the player wouldn't be able to notice that the collider doesn't match and the object clips through another slightly

[unique cave]

see? works as expected. didn't take weeks either (the way discord optimized gifs looks nice)

just make the box colliders child of the bucket and dublicate the child and rotate it with angle snapping

[tawdry wave]

hmm ill try

[unique cave]

you could for example use parenting to rotate chunk of colliders (make those colliders child of empty object that lays at the center of bucket) around the center of bucket

[tawdry wave]

colliders can't be rotated apparently, this makes it impossible

and the collider has to be on the object itself not on a rotated child object because that would break my scripts

[unique cave]

then you can either give up or modify your scripts

[tawdry wave]

feels like a feature unity should have built in

[unique cave]

what feature?

[tawdry wave]

concave colliders with rigidbody

There's stuff on the asset store for it but they all cost money

[unique cave]

I think that's not about unity. PhysX is made by Nvidia and therefore unity just can't change everything physics related (correct me if I'm wrong)

[unique cave]

what part on your scripts exactly would brake if you used child colliders?

[grizzled mango]

Hi i don't know if i'm in the good chat but i have this problem. my character go on the head of the ennemy when he charging me do you know why ?

[unique cave]

lol, we're discussing exactly same thing currently. see the error message

[tawdry wave]

the collider is detected when i want to pick up an object, and then i am taking that same object's mesh renderer to do stuff with it. I could set it to take the parent but that breaks objects where I have a rigidbody as a child so that isn't an option either

[unique cave]

um so is that on OnCollisionEnter or what? raycast?

[tawdry wave]

raycast

[unique cave]

how rigidbodies has anything to do with raycasts?

[tawdry wave]

the way my script works is that it shoots a raycast and looks for colliders. then if it detects a collider, it grabs the object's rigidbody and applies forces to it

[unique cave]

even if the documentation doesn't have anything indicating it, it seems RaycastHit.rigidbody gives you the rigidbody the raycast hits and if the rigidbody is not on the collider but on the parent of the collider, it still gives the rigidbody correctly

[tawdry wave]

Ah, I'm using GetComponent<Rigidbody>(), I didn't know there was another way

[unique cave]

I think RaycastHit.rigidbody is bit faster than GetComponent<Rigidbody>() too because it uses Collider.attachedRigidbody which is very likely cached and doesn't need to be searched using GetComponent

[unique cave]

so ig there's no problem anymore. just use child colliders right?

@tawdry wave in case you're interested, this is the code (just put this for the bucket) I used to make sure all the child (box) colliders gets drawn no mattter if they are selected or not. it's pretty hard to place the colliders if you don't see the other colliders: ```cs
using UnityEngine;

public class DrawColliders : MonoBehaviour
{
void OnDrawGizmos()
{
BoxCollider[] colliders = GetComponentsInChildren<BoxCollider>();
Gizmos.color = new Color(0.5686275f, 0.9568627f, 0.5450981f, 1f);
foreach (var col in colliders)
{
Gizmos.matrix = col.transform.localToWorldMatrix;
Gizmos.DrawWireCube(col.center, col.size);
}
}
}

[idle estuary]

I am confusion guys. OnTriggerEnter2D is when an external collider overlaps with a Trigger Collider on the object carrying the script right ? Or is it the other way around ?

[slate verge]

the real issue was that i kept forgetting to attach the script looool

but i have some additional logic that breaks the blueprint system if you dont use it, despite it being basically superflous

[unique cave]

I think it should work both way

[idle estuary]

Is there any reason to use a Composite collider on the tilemap apart from performance issues (Guessing it's the main reason it's used) ?

[timid dove]

Read the bottom of https://docs.unity3d.com/Manual/class-TilemapCollider2D.html

[idle estuary]

Yeah pretty much what I thought ^^" Thank you 🙂

Any idea on how I could detect that I'm in the middle of a Composite Tilemap Collider that is IsTrigger ?

[timid dove]

Can you be more specific about what you mean by "in the middle of"?

You normally use OnTriggerEnter/OnTriggerExit to detect trigger overlaps

[idle estuary]

Sure just a sec

Here I have a pool of water. It is part of a tilemap tagged "Water" that is IsTrigger. I have some code bound to My OnTriggerEnter2D on my playerscript with bool that affect some parameters like jumpheoght and horizontal speed. However the bool return true only when my player Rigidbody touches the bounds of the tilemap (here in red)

So in this screenshot my player is affected by the water physics and jump quite low, but since I'm immediatly not touching the bounds of the collider anymore, normal gravity kicks in and I sink like a rock.

[timid dove]

when are you not touching the bounds of the collider?

[idle estuary]

When jumping

[timid dove]

when you fly out of the top of it?

Not sure I understand

the bool return true only when my player Rigidbody touches the bounds of the tilemap (here in red)

What "bool" are you talking about?

Maybe show your code

[timid dove]

show your code

[idle estuary]

    private void OnTriggerEnter2D(Collider2D other)
    {
        if (other.gameObject.tag == "BearHead")
        {
            DeathByBear();
        }

        if (other.gameObject.tag == "Water")
        {
            Debug.Log("Enter");
            _isInWater = true;
        }
            
    }
    private void OnTriggerExit2D(Collider2D other)
    {
        if (other.gameObject.tag == "Water")
        {
        _isInWater = false;
        Debug.Log("Exit");
        }   
    }

[timid dove]

Ok and are the "Enter" and "Exit" logs printing at the correct/expected times?

[idle estuary]

Enter print when I touch the bounds

Exit when I'm not

Which includes the zone WITHIN the actualtilemap

[timid dove]

btw you can just do other.tag you don't need other.gameObject.tag. It's also better to do other.CompareTag("Water") as it doesn't allocate4 extra memory

[idle estuary]

didn't know that

[timid dove]

show how you set the collider up?

[idle estuary]

thx

[timid dove]

see how you have Geometry Type : Outlines

that's your issue

you want to change that to Polygons

[idle estuary]

It is indeed

Thank you 🙂

[vapid ridge]

is there any way to fix the problem when a rigidbody hops when when crossing between 2 objects that are the same height?

[carmine basin]

Is there an easy way to get a collider's volume, or do i just calculate it using the dimensions

I say easier, really just a bit shorter to write

[unique cave]

I don't think there is any easier way

[carmine basin]

alright, tu

[unique cave]

it actually seems to be bit more complicated to calculate the volume if the object is scaled

I think volume of sphere collider for example could be calculated like this: ```cs
SphereCollider collider = GetComponent<SphereCollider>();
Vector3 scale = transform.localScale;
scale.x = Mathf.Abs(scale.x);
scale.y = Mathf.Abs(scale.y);
scale.z = Mathf.Abs(scale.z);
float max = Mathf.Max(Mathf.Max(scale.x, scale.y), scale.z);
float radius = max * collider.radius;
float volume = Mathf.PI * radius * radius;

actually ig that doesn't even work for objects that has scaled parent on it

[carmine basin]

I'm planning on working on our dear friend, water

I know the law of programming - if it exists, don't code it again

but I would like to try it anyway

[bitter totem]

guys does anyone know how to make an object stick to the surface while moving?

[carmine basin]

like, it sticks on collision?

[bitter totem]

so it wont fly off

[carmine basin]

you could apply a force using transform.down

It pushes downwards relative to the object

[bitter totem]

didnt work

i think its because the downward force isnt enough

but no matter how much i multiply it, same result

[carmine basin]

try adding a float variable that's a multiplier, and mulitplying it by the mass

then you can adjust it on the fly to find a value

[bitter totem]

there are real problems when the box rotates too much

is there a way to limit its rotation force?

idk what you call it

torque?

[supple sparrow]

You could also constrain the position of the object to the height of the surface

could achieve that with a Raycast for example , but this would mean no more moving through forces

[supple sparrow]

limit rotation force
angular drag ?

[stuck bay]

What will I need to add collision detection to a Mixamo model?

[vapid ridge]

just add a mesh collider with the shape of the model. i think all models from other programs need to do that, probably

[stuck bay]

I see.

[vapid ridge]

oh yeah but can anyone help me here?

[supple sparrow]

Did you try to google that ? That's a known problem and you can try many things to fix it

[vapid ridge]

i did, and i tried to change the contact offset and it didn't seem to do anything

@supple sparrow

[supple sparrow]

a more advanced solution would be to write a script that merges all meshes into a single one

[vapid ridge]

i guess, but i'll probably just model it instead if i need to do that

[supple sparrow]

Alright, I never made something close to a rolling ball game before, so can't help much more. Hopefully someone who did can give you better ideas

[neat coral]

What did you change it to?

[vapid ridge]

1000, 10, and 0

[vapid ridge]

@neat coral?

[vapid ridge]

okay i know people have lives, but i am tired of this

[supple sparrow]

Try a small value like 0.0001

[vapid ridge]

it doesn't work

well thanks anyway

[vapid ridge]

can anyone else help?

[neat coral]

It should work

You can also merge the meshes

https://forum.unity.com/threads/rolling-ball-bouncing-issues-preventing-upgrade-past-2018-2.1054418/

Are you using continuous collision detection?

[vapid ridge]

yes, actually for some reason continuous makes it more likely to jump

it seems to be fine now? i'm not sure what i did, but it hasn't really happened for a while after testing a lot

sort of, maybe it just happens less

also i just read the thing and in my process, i basically recreated the ramps in blender where i merged everything, but i still had the problem. it still happens now, it's just less

[buoyant oasis]

Hello everyone, asking for a friend but I was wondering if you could get a collider that isn't just a cube, and instead fit to the object's shape, hopefully that makes sense.

[supple sparrow]

Yes, a mesh collider

https://docs.unity3d.com/Manual/class-MeshCollider.html

[lapis plaza]

contact modifications

I made this example: https://forum.unity.com/threads/experimental-contacts-modification-api.924809/#post-6482950
here's the ball problem discussed more in depth: https://forum.unity.com/threads/experimental-contacts-modification-api.924809/page-2#post-6720985

@vapid ridge

[supple sparrow]

Oh nice it's out of experimental now ?

[lapis plaza]

yeah it's been out since 2021.2 🙂

2012.2.0a12+ to be more specific

[lone goblet]

anyone got a grab physics for a vr game?

[supple sparrow]

I'm still on 2020, because you know, DOTS. But it's nice to hear, thanks for the info 😉

[lapis plaza]

2022 also has the updates and DOTS 0.5 should work there, right?

I haven't really followed the 0.50 discussion that much nor tested it myself, just saw the mention they plan to support 2020 and 2022 but not 2021

[supple sparrow]

2022 is still tech stream ? I'm not this far in versions ^^

[lapis plaza]

2022 LTS is like one year away

2022.1 tech stream should go live soon, they are on final betas now

[supple sparrow]

0.50 is 2020.3.30 min, I think 2021 support is expected for this quarter and not sure about 2022

BUt I might be wrong for anything starting from 2021, because like I said I didnt do the jump

[lapis plaza]

2021 LTS is about to get out now too, but I'd be cautious about it if DOTS is important

Unity's own messaging has been for a long time that they will just skip 2021 but this will probably get more clear now that GDC has Q&A on it

(for DOTS support)

[neat coral]

are you sure it's actually aligned?

[lapis plaza]

there could be extra edges/holes in the seams

[vale grail]

Hi, i have a car using a WheelCollider. When the speed is between 4-12 u/s the wheel behaves weird (see video, the time scale is set to 0.1f to see the wheels rotation) and rolls uneven. Also the speed of the car is jittering. How can i prevent this? Thanks in advance 🙂

[regal ingot]

Evening guys. Anyone got any idea why my HingeJoint will move the collider but not the actual mesh itself? Having a nightmare with this

[unique cave]

Is the door set as static?

[regal ingot]

Wow, you solved it in like 12 seconds and I've been trying for hours to solve it, thank you!
Sorry for the n00b question, I've only used the 'static' field with navMesh agents I didn't know it would effect hinges too.

[unique cave]

I think it’s not about the hinge particularly. Static meshes can’t be moved runtime and if you try to move them, it just stays the same place

[unique cave]

You could just set it to navmesh static and leave the others unchecked if the navmesh static is the only thing you need

Id imagine being only navigation static doesn’t prevent objects from moving, not sure tho

[regal ingot]

I'm not sure if I need it for navmesh because things are going around it, not on it, but I will experiment and see

[lunar yarrow]

I have a glitch where if i jump near a block my model clips/glitches up and down and i have no idea why this happens

[inner thistle]

Unless you show the code, neither have we

probably a groundcheck gone wrong

[lunar yarrow]

ok

ill send a pic of scripts

(Player motor^)

(input manager)

[timid dove]

this is a classic CC pitfall

Using Move twice in one frame is what causes this

You only want to call Move one time per frame

[viral pilot]

I have colliders on the AI agents and Characters body parts, it shows all of them as Static Colliders, does it cause the static world rebuild? should I put Rigidbody on them to put them in dynamic world?

[timid dove]

If there's no Rigidbody on an object with a collider, it's considered a static collider, yes.

[lunar yarrow]

is there a tutorial that can help me fix? im new to coding help would be much appreciated

[supple sparrow]

He pretty much explained to you how to fix though

[timid dove]

You don't need a tutorial. It's simple. Only call Move once per frame

[lunar yarrow]

How tho? Im still bad at coding

Lol sry

[timid dove]

You just add the two vectors and call Move with the result

each call to Move right now is taking a Vector3

add those two together and call Move only once

[fervent prawn]

so am having a problem, i am using a slider to rotate an object, and have a ball that I want to move, I use the slider to rotate the object, and the sphere acts like the cube didnt rotate...?

[honest walrus]

hello. question. rigibody on xr rig causes it to fall over immediately upon entering play mode, and also falls over or spins when object grabbed on ray grab contacts xr rig. please help

[vapid ridge]

sorry, i wasn't sure what to respond. i'll probably live with the issue since it sort of fixed itself out earlier

[vapid ridge]

^

[cloud fossil]

Where could I find the physics code for when two rigidbodies collide?

[supple sparrow]

https://docs.unity3d.com/ScriptReference/Rigidbody.OnCollisionEnter.html

[cloud fossil]

I mean when unity does it automatically

I have a target, that when I hit it, it only moves along one axis:
https://www.youtube.com/watch?v=KAdf8S0QDPM
The only code that's related is spawn/shoot bullet rigidbody, and spawn new target when hit.
current update to this, I've done Debug.Log(collision.impulse);
and I get (0.0, 0.0, -50.0) and (0.0, 0.0, 50.0) it seems to 1: switch between +z and -z every target,
2: get no x and y impulse

Found out why it's reversing, but why am I not getting any x and y impulse?

[timid dove]

Why should it?
Does either object even have a Rigidbody?
Are you moving the body in a phyics-aware way?

[timid dove]

do you have constraints on the rigidbody?

Oh it may also just be due to the nature of the shape of that body being perfectly flat and the fact that you're hitting it with a perfectly spherical bullet.

There's exactly one collision point and the impulse will be directly opposite the surface normal

sort of how billiards work

in real life there'd be some deformation of the ball/target and imparting of a slight friction force sideways but this is an idealized simulation

That's my theory anyway 😄

Notice that when you hit the edge of the target things happen a little differently. which is consistent with what I'm saying

Although the fact that it's not rotating at all is very odd

[cloud fossil]

No constraints nothing. The thing I want it to do is this: https://www.youtube.com/watch?v=6Vkmgki9BsU
and all that is different is size of one axis

the bullet is shot with

Rigidbody clone;
clone = Instantiate(GS.Projectile, BulletSpawnPoint.position, BulletSpawnPoint.rotation);
clone.velocity = clone.transform.forward * GS.BulletSpeed;

what it feels like to me, is the bullet velocity is somehow still in local position, and it transfers to the target in local position

[fervent prawn]

they both have rigidbody

[cloud fossil]

But I've started with the cube, then made it smaller, and once it gets to 1,1,0.5 scale it stops reacting correctly

[timid dove]

and my second question?

[fervent prawn]

yes

[timid dove]

how?

What's the way that you are rotating it?

[fervent prawn]

ok wait it somewhat works now, just when I move it too fast the balls goes right through the platform

[timid dove]

still sounds like you're rotating it in a way that is not physics aware

you need to rotate it using Rigidbody.MoveRotation or by adding torque or by setting the angular velocity

[fervent prawn]

just using transform.rotate

[timid dove]

that's the issue

that bypasses the physics engine

[fervent prawn]

ah

error CS0542: 'Rotate': member names cannot be the same as their enclosing type

huh

[timid dove]

you have a class called Rotate and you tried to make a method, field or property (a member) inside it also called Rotate

[fervent prawn]

yes, I fixed it

[fervent prawn]

it says my script doesnt contain a definition for rigidbody

[timid dove]

what does

you have to use your actual variable you created and assigned for the Rigidbody

[fervent prawn]

oh ok

I dont use c# much

'GameObject' does not contain a definition for 'MoveRotation'

am I doing this correctly RotateObject.MoveRotation (Vector3.up * delta * 360);

[cloud fossil]

so I tried attaching a cube with mass on the back of the target with with a fixed joint (if mass is what's causing it not to work) and didn't fix it, but if I shoot the cube it'll physics right

[lunar yarrow]

Im sorry but i understood nothing, i know what a vector is but i know Little to no code

[cloud fossil]

Damnit, buried deep in the rigidbody page "Note that continuous collision detection is intended as a safety net to catch collisions in cases where objects would otherwise pass through each other, but will not deliver physically accurate collision results"

[timid dove]

no like I said before it's part of the Rigidbody

[trim solar]

https://www.youtube.com/watch?v=Z4HA8zJhGEk&ab_channel=GameDevChef

I followed this tutorial for making a car moveable. i made everything excactly as he did but somehow my car is "bumping" on the ground. looks like the tires/wheels are vibrating. what could it cause?

if i set the wheelcollider inside the box collider of the car, its not vibrating. but then the car cannot drive because the wheels are not touching the ground

[trim solar]

its completly set to default and what lots of resources inclusive unity guides/docs said

somehow the object is vibrating on a normal ground cube/plane

this is runtime:

Would be nice if someone can explain me, whats happening there

https://www.youtube.com/watch?v=6RC9LsN_wmM&ab_channel=SpeedTutor

WTF
He has exactly the problem i have. He said i need to attach a second box collider but why?

not even working unfortunately

[woeful shard]

Did you try changing physics collision detection to continuous?

[trim solar]

yes

not working 😦

i also tried changing the center of mass from the rigidbody, same result

The main thing i dont understand is: if i do exacty 1:1 what others do, why its not working for me?

is it a bug maybe in unity 2021?

[craggy dune]

do colliders need sprite renderer component to work?

[trim solar]

they usally work withot any renderer

[craggy dune]

but the "to be collided" object needs a rigidbody component to work no?

[woeful shard]

Try freezing rotation constraint along the axis which is perpendicular to the centre?

[trim solar]

no, a normal cube has just a box collider and is also working fine

[trim solar]

i tried but then i cant move it anyways. but i want my car/wheels to move, not to be static 😄

[woeful shard]

And I hope you are using rigidbody functions to move and not transform to move

[trim solar]

i do 😄

i mean actually i use the wheel methods, not the rigidbody

[woeful shard]

https://answers.unity.com/questions/869470/how-to-prevent-collider-from-shaking-when-collidin.html

[trim solar]

i use it in fixedupdate only

but even without any scripts attached, just using the plain Unity features, its vibrating somehow

[trim solar]

at the start of this video you can see how it looks

[woeful shard]

Yeah

[lunar yarrow]

if i needed a tutorial what should i type

[wispy tinsel]

Guys, here's my problem:
I am making a system that will place props around circle and avoid overlaps between those props.
But so far, I have no luck using Unity physics.
Here code I use and it wouldn't work correctly: either array[0] will be null or distance itself would be 0
Using this distance I determine on what angle I should move those props around circle.

            get
            {
                Collider2D[] overlapped = new Collider2D[1];
                collider.OverlapCollider(filter, overlapped);
                var overlappedCol = overlapped[0];
                if (overlappedCol == null)
                {
                    return 0f;
                }
                var distance = Physics2D.Distance(collider, overlappedCol);
                if (distance.isOverlapped)
                {
                    return distance.distance;
                }
                return 0f;
            }

So I'm getting rather desperate. Any help?

[trim solar]

anyone has another idea? I have tested the same things in another project and it seems to work there. So what could break that except the physic project settings?

ok nvm. idk why but after 3 restarts it just got away lol

ah okay no

its something with the "gravity y" field in physics project settings. with -10 it works without stuttering and with -500 (which is default i think) its applying gravity as usual and then the wheels try to get gravity but they cant

[rough sentinel]

hey, I have a CharacterController based character that I need to teleport, and afaik the only way to do that is to disable the controller, change its transform, then re enable it
So I do that, problem is I'm teleporting it out of a trigger, but it doesn't call OnTriggerExit for some reason, which causes issues with some other systems
Any way to fix that?

[timid dove]

Two problems:

• Generally you will only get OnTriggerEnter/OnTriggerExit calls when one of the two objects has a Rigidbody. I'll presume the other object has one in this case?
• By disabling the CC you are actually disabling the collider (The cc is a collider). physics callbacks like OnTriggerExit rely on colliders to work

[rough sentinel]

I ended up solving the problem
I'm no longer disabling the CC, instead I activated "auto sync transform"
yes the other object has a kinematic RB

I originally worked under the assumption that the CC would keep references to the triggers it's currently in, then when re-enabled, check if it's still inside those triggers, guess that's not a thing

[median rampart]

how do I get my CharacterController to go up ramps?

slope limit is set to 0

but it just stands still if you try to walk up a ramp

if I set the gravity all the way up to 500 and hold down the jump button I can walk up the ramp

but how do I make it do that automatically?

[timid dove]

if slope limit is set to 0 then it can't climb slopes

set a higher slope limit

[median rampart]

OHH

I had it backwards

i thought it was a ceiling but it was a floor

thanks

[orchid tiger]

Hey all, is there a way to Raycast and get a RaycastHit contact.point back with the world coordinates of a mesh surface? Does this require a mesh collider, or is there a way to hit the mesh of the 3d object itself and get back the point of contact?

[timid dove]

it requires a mesh collider

raycasts only work on colliders

well it requires a collider of any kind

but if you want a custom non-primitive shape it'll be a MeshCollider

[sage osprey]

hello guys

[orchid tiger]

darn, I figured. My issue is I have a capsule collider on my player, and when a bullet hits I have the impact fx spawn at the contact.point. This looks alright actually, but I wanted to see if I could make it look even better by spawning closer to the surface of the mesh itself

[orchid tiger]

Yeah I was thinking this, like a simple mesh that is closer to the player body?

[timid dove]

you can use a MeshCollider for the bullets and capsule for player movement

with layer based collisions and layermasks etc

[orchid tiger]

nice, I will give that a try, thanks!

[timid dove]

you would want to put the two different colliders on different child objects of the player

and give thme different layers

[orchid tiger]

like arms, legs etc

sounds good, thank you

[surreal garden]

hey guys quick question about colliders

so basically, I have a couple of cubes in my world and I want them to get destroyed when I move into them with my main camera

so I gave the blocks the "is trigger" property in the box collider and the following script:

however, when I move into the blocks with the camera, nothing happens and I believe it's because I didn't give the camera a collider property

which of these exactly do I give that property to though?

do I just give the "Main Camera" a rigidbody and turn on "Is Trigger"?

[umbral drum]

do you wan't to destroy the cubes when they become visible inside your camera ? if so, try this:

    void OnBecameVisible()
    {
        //destroy cubes
    }

[surreal garden]

hmm I just want them to get destroyed when I touch them with the camera (I can move around with wasd/arrow keys)

and from what I learned so far, onTrigger is what I should be using

[umbral drum]

give your "Main Camera" object a collider and mark it as a trigger, for the triggerenter to happen any of the colliding objects must have a rigidbody (the collectible gameobject or the camera itself)

also make sure there's a "MainCamera" tag in your "Main Camera" gameobject, if you created the camera from scratch it won't have by default

[surreal garden]

okay so I actually tried that earlier:

but it wasn't doing anything

[surreal garden]

yup it has the tag

[surreal garden]

wait does the maincamera need a script as well? I though only the cube would need a script

here's the tag btw:

oh hey I got it to work

I had to give the cube a no-gravity kinematic rigidbody and it worked

[cold rivet]

does anyone have a good example of a 2D physics based player controller that uses AddForce to move rather than directly setting the velocity? nothing i try feels good to play as

like, setting the velocity feels good to play as, but i want my player to be affected by external physics movements, like knockback from an explosion

[umbral drum]

nice, sorry for answering it late

[umbral drum]

if you wan't something responsive i think it's better to modify the velocity directly or use MovePosition, with addforces you're "fighting with other unknown forces"

[cold rivet]

i see what you mean. ill try to impliment that

[lunar yarrow]

idk why i cant jump

if someone can help it would be much appreciated thanks'

[prime flower]

MovePosition won’t apply proper physics forces though

So it’s not a solution for something attempting proper simulation

[supple sparrow]

You never call Jump in this screenshot

• you didnt fix a previous problem you asked for : you call Move() on your character controller twice

so it doesn't give the will to help you 😛

[keen lintel]

Hi guys, so my player does this thing when i press W into a wall

why?

[timid dove]

Because you're not moving it with the physics engine

You're teleporting it with the Transform

So it's teleporting inside the wall and getting pushed out

[keen lintel]

Oh ok ty

Now i need to learn how to do that

asdkmasd

[stuck bay]

when i push down a rigidbody connected to a spring slowly, it starts to get jittery. i need the spring to provide resistance and launch the ball when released but i don't want it to be shaking wildly, any ideas?

the force is applied every frame as long as a button is pressed so you can choose when to release

[neat coral]

don't push the body, pull the spring

[stuck bay]

any pointers on that? not sure how to do that, i'm not very used to unity 😅

[stuck bay]

anything?.. can't find anything on google for how i'd "pull the spring"

[echo ivy]

how would i create a bearing?

[neat coral]

with the strength of your mind

[echo ivy]

what?

[neat coral]

sheer force of spirit

[echo ivy]

are you being serious?

[neat coral]

I guess you might be looking for a joint?

[echo ivy]

yes
a joint that can spin

so you could attach a car wheel to it for example to make the wheel be able to roll

[neat coral]

look for unity wheel tutorial

[echo ivy]

its coming up with wheel colliders

also this isnt specifically for a wheel

[magic needle]

You can use a hinge joint: https://docs.unity3d.com/Manual/class-HingeJoint.html
There is also other joint types depending on what you are trying to do.

[silent scroll]

Hi, I am trying to shoot a raycast out of a player object in my multiplayer game, and I need the ray to ignore only the collider of the player that shot it. So far the only solutions I could find on google were ones using layermasks but I don't want to have to create and assign a new layermask whenever a player joins. Is there a way to have raycasts ignore a single object without using a layermask?

[neat coral]

you could change the layer temporarily, just the time to shoot the raycast

or you could shoot a first ray and if it's the player shoot again from the hit position

[silent scroll]

I dont think that the temporary layer change would work because in the unlikely event of two players shooting at the exact same time then the bullets would go through the other person but I will try the recast from the hit position, thank you.

[neat coral]

is your stuff multithreaded?

otherwise everything is concurrent afaik

[silent scroll]

I have no idea lol I think so?

[neat coral]

it isn't by default

[silent scroll]

probably not then how I do I tell

[neat coral]

if you don't know then you are most probably fine

[silent scroll]

ok

[wispy tinsel]

What is correct term/helper method to detect on what distance colliders overlap each other?

I have collider A and collider B. And I need to know on what distance they overlap each other

as in, to know minimum distance to get rid of overlap

[lucid sorrel]

Hello Everyone, im getting an issue when working with wheel colliders which is that they keep moving towards one direction(x). Even when im not giving it an input. Also when i do press the forward button it starts to lean on that direction(x).

[lucid sorrel]

i tried interpolate and extrapolate both gave the same results

[neat coral]

It's called penetration depth

https://docs.unity3d.com/ScriptReference/Physics.ComputePenetration.html

[wide nebula]

Remove seams by using a single collider, and don't use something like a box collider with a hard edge for the player.

[timid dove]

You'd have to explain the setup and show the code

[cold rivet]

im getting a problem with my physics. As you can see in the video/image, when the player objects jumps into the wall, it goes INTO the wall before the engine puts it back. hte problem is that my boxcast for ground detection gets triggered by this. Whats the solution?

[timid dove]

move your object in a physics friendly way

seems like you're teleporting it around via the Transform

[cloud fossil]

actual physics question: does this feel weird/wrong because my mind is in "video games" mode? bullet moves at 100m/s. If I factored in mass it would make the effect even less, wouldn't it?
https://www.youtube.com/watch?v=8dMDKJMrP3A
rb.AddForceAtPosition((collision.collider.transform.forward * 100), collision.GetContact(0).point);

[cold rivet]

i am not, i am only setting rigidbody velocity

[timid dove]

use continuous collision detection instead of discrete?

[cold rivet]

nope, problem still occurs

[timid dove]

show the code

[cold rivet]

sure, 1 sec

[timid dove]

wich object is that code on? mass is factored into the force calculation automatically, though typically for a one-off hit like this you'd use ForceMode.Impulse

[cold rivet]

https://pastebin.com/e64esi5q

[cloud fossil]

The target. I found out physics engine doesn't like continuous collision so doing it manually

[timid dove]

it seems like you might have constrained one or more movement axes for the target? Also, again, you should use Impulse

[cold rivet]

are you reffering to me or zibba? If me, yes,my current rigidbody on the player object looks like this,

[timid dove]

zibba

[cloud fossil]

woo, it was the forcemode.impulse

[graceful arrow]

not sure if this belongs here - but I have a problem in that sometimes the player is able to wall jump when he is not able to - I assume it's because if the player runs up against the wall with enough speed, he is able to move into the wall? And then use the wall as a jumping board?

It only happens when the player A.) has speed and B.) jumps towards a wall

I've already reduced the players boxcast

anyways I guess im hoping for someone to A.) tell me if my theory is correct or if its because of a different problem and B.) Point me towards a solution?

[gusty mauve]

Hey so uhh my player keeps felling down slowly like fall in the void

[timid dove]

I think there's maybe another collider covering the inside of the box possibly

Check for OnCollisionEnter2D

and print out the name of anything it collides with

[timid dove]

print the name of what it collided with

[timid dove]

what object is this script on?

ahd what's the "heart box"?

[timid dove]

Do you have two rigidbodies?

What's your heart's hierarchy and components look like

That's wrong

If there's two rigidbodies they're treated as separate objects in the physics engine

Wehy

?

Why would they be separate objects then

I'm confused

Oh oh

Ok nvm I understand

What kind of Colliders are you using for the heart box

Sounds like you've got one that's covering the middle too though

[wanton storm]

Hey quick question, so I want to have a player that can aim in 360 degrees around themselves in a 2d platforming game like Mario, I set up a firing point and attached a rigidbody to the firing point allowing me to add a weapon script to make it follow the angle of the mouse, this works, however the actual player character rotates with this as well. Is it possible to keep the firing point attached to the character without having him get rotated as well?

I've tried freezing the playable character's Z rotation which hasn't worked

[toxic trout]

Hi, I've run into a problem with implementing a simple crouching system with Character Controller = Basically, when I press the crouch key I modify the CC's Height and Centre to make the player go down. This works pretty well, but when I'm crouching down, the CC shrinks and sort of drops down to the ground, creating an uneven crouch time and some other problems. Here's a video of what I'm talking about:

https://i.imgur.com/Tba41Gv.mp4

Is there maybe a way to make it so that the CC's collider shrinks down while remaining grounded, or some other way of going about this? As you can see in the video this creates a problem where when you crouch near a ledge, you actually go up on top of it because of the collider shrinking in the air.

Thanks, hope I explained it well enough

[wanton storm]

I believe I didn't illustrate my point earlier at all and that was my own fault, here is the game in execution, ideally the orb rotate around the player with the mouse rather than having the player also rotate around, however in execution they are both rotating, even if I freeze the Z axis of the player. I have the orb attached to the player as it's own class "weapon" so that it is always attached to the player. However this attachment is causing the problem, is it possible to have only the weapon follow the mouse without the player character, this way the orb will be "rotating" around the player. I have a Rigidbody attached to the weapon which may also be the cause of the problem however the rigidbody is used to move the orb in the weapon class. Unless it is possible to move the orb without referencing rigidbody. Below is the code I used in the weapon class in order to have the orb follow the code

[wanton storm]

Solved

Needed a pivot point

[wanton storm]

Is it possible to have a pivot point move in relation to it's parent

I have a pivot point set slightly infront of my playable character, however it does not follow him around as he moves about, is there a way to force the pivot point to move with the playable character

[timid dove]

if it's a child of the player, it will move with the player

[wanton storm]

It doesn't appear to be, I'll send a video to show what I mean

Apologies for the noise I had no idea mic was on

[timid dove]

this is more likely a code issue than anything else

but you can see even in your video that the local position of the object is not changing in the inspector

this means it's absolutely following its parent

[wanton storm]

Huh, that is odd then

I think maybe it might be some error with the camera?

In terms of call maybe

This is the code for the pivot

Could it be a thing that the camera doesn't update or something

Hmmm no does not seem to be the camera

[timid dove]

why are you doing WorldToScreenPoint on transform.localPosition

localPosition is not a world space point

that function needs a world space point as the input

hence the name

[wanton storm]

Oh god you gotta be joking I made a typo

Yeah I see the error now, a few hours and a bit of amnesia gave me a slip, sorry

[timid jewel]

Guys, I am detecting objects with Raycasts, and i want to make objects invisible/not detected by raycast when a smoke screen is added in screen

Is there any way to achieve this? please help me 🙏

[timid dove]

GIve the smoke a collider too

so the ray will hit the smoke instead of the thing behind it

[timid jewel]

Yes awesome thank you , problem is gameobject of interest can come in and out of smoke, when it is out of smoke, I don't want it to be confused with smoke

[timid jewel]

Oh okay got it now 👍

One more question,with unity particle system if I create the smoke I can add colliders right?

[timid dove]

no the collider shouldn't be part of the particle system

it's a separate component

You can have a GameObject with a ParticleSystem and a Collider on it

[timid jewel]

Oh yaa, that would be good,
so based on smoke location and spread, we would need to change the collider size?

[timid dove]

maybe

depends how you design things.

[timid jewel]

Awesome, thank you for helping😀😀

[dreamy quail]

i have a mesh that is the parent of an empty object
this empty object has the open xr tracked pose driver (new input system) script
i want this mesh to collide with rigid bodies

openxr quest 2

2020.3.17f1

im making a simple ping pong game

[timid dove]

You have to move the object via physics for it to interact with rigidbodies properly. In VR that generally means letting the actual VR hands be a proxy object and then you have a kinematic rigidbody that MovePosition and MoveRotation its way around following the hands in FixedUpdate.

[dreamy quail]

oh ok

ill try that tomorrow

thx

[snow glacier]

So I am wanting to make a little sandbox game that utilizes active ragdolls and ik

If I use this method for the active ragdolls

Connect the hips to a kinematic rigid body.
Create a rigid body with the direction you want your hips to have. Then make a joint that connects that body to the hips (or root) of your active ragdoll. Leave the default target rotation and set the angular drives to be much stronger than any individual part of the body

I should be able to make an ik system around it right?

[cloud fossil]

Is continuous collision detection broken for triggers?

[snow glacier]

No

But my old system for ik on huminoids is broken when I tried to apply it to the active ragdoll

Altho I am trying to fix it and it works better now and doesn't throw errors anymore

[obtuse crystal]

Getting an error: convex mesh from source polygon limit 256
Trying to deform a mesh with script. Game also freezes on collision.

https://pastebin.com/GZniJb4H

[tired island]

ok this question is going to sound very, um, suspicious

but

im creating a model in blender for unity and i want to add some sort of jiggle physics to interact with unity's physics systems

specifically, it's for a like cable on a gun - i think it would look better if it moved with wind forces or when falling, that kind of thing

this sounds crazily difficult, so, does anyone have any ideas? i assume it must use blender's bones

[honest granite]

character falls through the floor of a helicopter, it has a character controler and a convex mesh, the heli has a convex mesh aswell as an extra box collider which tries to stop the player falling through the floor but it wont help

im not aplying any animations

nvm, ive run into another problem

https://answers.unity.com/questions/1633550/moving-platform-and-charactercontrollermove-not-wo.html -got it working with the 2nd answer

[dreamy quail]

how would i move position and move rotation?

[timid dove]

They are methods on Rigidbody

https://docs.unity3d.com/ScriptReference/Rigidbody.MovePosition.html
https://docs.unity3d.com/ScriptReference/Rigidbody.MoveRotation.html

[dreamy quail]

oh ok
i was planning on using this code from stack overflow to get the pos of the empty game object that has its transform set to the controller

GameObject LeftHand= GameObject.Find ("LeftHand"); Transform LeftHandTransform = LeftHand.transform; // get LeftHand position Vector3 position = LeftHandTransform.position;

i could replace position in the example script with LeftHandTransform.Position, correct?

[timid dove]

Highly recommend not using GameObject.Find or at least only using it once and saving the result in a variable for reuse

[dreamy quail]

oh ok

what should i use?

[timid dove]

a simple serialized reference

drag & drop

[dreamy quail]

bolt?

[timid dove]

no...

the inspector

[dreamy quail]

im confused

im new to c# and unity

[timid dove]

I know

I'm talking about how to get a reference to LeftHand

nothing to do with the Rigidbody yet

[dreamy quail]

oh ok

so i drag the left hand from my hierarchy into visual studio?

i made this in bolt

i think it will work

will test in an hour

i need to check if the items are less than 0.001 apart so it doesnt jitter, but this should work as a prototype

[carmine basin]

does stuff rotate when attached via spring joint?

[ashen gale]

anyone know why this is happening? cant find anything about i

whenever i got anywhere it lifts up

[stuck bay]

i have a physics setup ehre

https://media.discordapp.net/attachments/502171560359100437/958091191306551426/parkour2.gif

ia it possible to limit the horizontal velocity without destroying rigidbody logic

[ashen gale]

fixed it

[warped slate]

Is there a way to have a rigidbody smoothly interpolate while running physics operations in both Update and FixedUpdate?

I have a 2D top-down controller with movement and mouse aiming. Everything runs smoothly except the rotation of the player is jittery on low end computers. I assume this has something to do with the framerate compared to the FixedUpdate frequency. If I move the Aim function to Update, the aiming is smooth again because it's running at the correct framerate.

However, if I rotate the rigidbody in Update and move it in FixedUpdate, the rigidbody interpolation no longer works and the movement becomes jittery. Is there a way for me to get rid of the jitter when doing physics operations in both Update and FixedUpdate?

[timid dove]

you need to accumulate input in Update and then consume it all in FixedUpdate

for example...

Vector2 accumulatedMouse;

void Update() {
  accumulatedMouse += new Vector2(Input.GetAxis("Mouse X"), Input.GetAxis("Mouse Y"));
}

void FixedUpdate() {
  // Do rotation code with accumulatedMouse data
  accumulatedMouse = Vector2.zero;
}```

[dreamy quail]

didnt work at all

it wouldnt return any values

the trans pos get was always 0

[warped slate]

Thanks, it works now!

[timid dove]

I don't really know how bolt works tbh

I thought we were talking about regular code

[dreamy quail]

it works the same way

im running transform.positionget(GameObject.LeftHand)
i think

[cobalt bear]

when i use Physic.raycast with a UI button it hits multiple times, how can i fix that?

[unique cave]

No way you hit multiple times with single raycast. Raycast retuns exactly one hit (or none) and never more

If you raycast multiple times, you can hit once every time ofc

[timid dove]

Also Physics.Raycast would never hit a UI button

it only hits 3D Colliders

[unique cave]

unless you add colliders for UI elements. for world space UI elements that would make sense sometimes

[timid dove]

While I think that might be technically possible - you're better off just using the event system which already has functionality for graphic raycasting

[unique cave]

In cases you want to hit UI elements (Screen Space - Overlay would not work tho) like any other 3d objects why not

[timid dove]

you mean like in game objects interacting with them?

[unique cave]

yeah ig

[timid dove]

¯_(ツ)_/¯

[unique cave]

but that's most likely not what they are doing

imagine adding Rigdibody to UI element on Screen Space - Overlay canvas 👀

[iron wing]

Do you guys know any way to make hinge joints without rigidbodies? (like, a new script, not unity's compononent)
I keep struggling and want to make a pushable door that works with a character controller

To be clearer : I want to make a pushable door that works with a character controller

[timid dove]

What do you mean by "works with a character controller"?

Like the door has a CharacterController?

Or the player has one?

And what kind of interaction are you hoping to achieve?

Because if it's the player that has a CC, you can achieve a pushable door with normal Rigidbodies and joints

You just need to use this https://docs.unity3d.com/ScriptReference/MonoBehaviour.OnControllerColliderHit.html and apply a force to the door in that callback

[vernal pebble]

Why these two colliders can't collide perfectly in my platformer?

another discovery, these three square i made, same problem

how do i fix those ugly physics, chat?

every object i collide leaves this ugly gap

[carmine basin]

That's the contact offset in the Physics part of Project Settings

[vernal pebble]

I set this to 0.0025 and it is perfect enough, Fixed

[neat coral]

you're the most well placed to tell if it affects negatively the feel of the car in other situations

[cold oracle]

//Not tested but should do the job
public Rigidbody rb;
public float maxVelocity = 10f;

private void FixedUpdate() {
  float v = rb.velocity.y;
  rb.velocity.y = v.normalized * maxVelocity;
}

[prime flower]

https://streamable.com/favjw3

basically volleyball with pure physics

rigidbodies and joints

[umbral drum]

hi, in the screenshot below the colliders are perfect, however they aren't touching at all, does someone know how to fix this gap ?

[timid dove]

in physics 2d settings there's something called default contact offset

[umbral drum]

thanks, it worked

[shrewd shoal]

anyone know how in the world boxcasts work because I cant get them to work at all

it triggers correctly on the right ground but not on the slope

both have the same tags and layers and colliders and stuff

float ExtraDistance = 0.50f;
Vector3 size = new Vector3(0.5f, 0.01f, 0.5f);
Physics.BoxCast(new Vector3(0f, -0.01f, 0f) + this.transform.position, size, Vector3.down, out raycastHit, this.transform.rotation, ExtraDistance, mask))```

and it seems no value that I change in the cast changes the outcome of when its triggered

and ive tried visualizing it with gizmos at least to the best of my ability and it clearly hits

Gizmos.DrawCube(new Vector3(0f, -0.01f, 0f) + this.transform.position, new Vector3(0.5f, 0.01f, 0.5f) * 2) //*2 because the cast takes in half of the size;

so I just dont have a clue what is going wrong

[jovial wraith]

Is the slope overlapping the cast at the start? casts only detect new objects that overlap it, not ones that overlap it from the start

[shrewd shoal]

no its not

and im pretty sure it does detect old objects

because it debugs the floor like 50 times a second

[shrewd shoal]

the funny thing is if I do the exact same pos and direction with a normal raycast it works fine

maybe thats because im not specifying a distance but the box cast is going like a meter down so it has to be able to hit the ramp

because the bottom of the player and the ramp is way less then a meter

[timid dove]

How is your layer mask initialized?
Is the thing it's hitting inside the box at the start of the cast?
Are you not reading the result of the cast (you seem to be ignoring the return value)

[shrewd shoal]

this is what im doing ```csharp
if (Physics.BoxCast(new Vector3(0f, -0.01f, 0f) + this.transform.position, size, Vector3.down, out raycastHit, this.transform.rotation, ExtraDistance, mask))
{
//hit something
//Debug.Log(raycastHit.collider.gameObject.name);
return true;
}
else
{
//did not hit anything
Debug.Log("No Hit");
return false;
}

just summed it down for this

layer mask is just set to the player and then this mask = ~mask; at the awake

to make it so its every layer except the player

nothing is hitting the box at the start because the player is spawned mid air

[timid dove]

how did you set it to the player layer?

[shrewd shoal]

[SerializeField] private LayerMask mask;

and then inspector

[timid dove]

ok good

and the object you're trying to hit, it has a collider?

[shrewd shoal]

yep

[timid dove]

And the collider is not on the player layer?

And where do size and ExtraDistance come from?

[shrewd shoal]

ramp has no layer or tag set

[timid dove]

If this collision is hitting that means that the boxcast starts overlapping the object, doesn't it?

BoxCast won't hit anything that the box starts overlapping

only things that it hits as it is "cast" through the scene

[shrewd shoal]

im pretty sure that the boxcast just returns anything it hits first along the path

Description: Casts the box along a ray and returns detailed information on what was hit.

because theres also checkbox, overlap box, etc

[timid dove]

Like all 3D physics casts it's subject to this caveat:
https://docs.unity3d.com/ScriptReference/Physics.Raycast.html

Notes: Raycasts will not detect Colliders for which the Raycast origin is inside the Collider.

[shrewd shoal]

pretty sure its not inside the collider

[timid dove]

Isn't your DrawBox showing that it is?

Also note spherecast documentation has that note too but they forgot it for BoxCast I guess https://docs.unity3d.com/ScriptReference/Physics.SphereCast.html

[shrewd shoal]

it says the orgin is inside the collider

the orgin for this is the center bottom of the player

[timid dove]

right but

any part of the box overlapping at the start will make it ignore

[shrewd shoal]

then why when its on flat ground does it work

thats closer then if its on a ramp

[timid dove]

WHhere's the player's pivot?

[shrewd shoal]

very bottom of the player

[timid dove]

part of the box overlaps when it's on the ramp

i guess not so for when it's on the ground

is this all just for a grounded check?

Why not use CheckBox/OverlapBox instead?

[shrewd shoal]

those just straight up did nothing when I tried

[timid dove]

they work fine

if you give the right parameters

[shrewd shoal]

whats the difference between them

one seems to get everything

[timid dove]

CheckBox just says yes or no that something is there

Overlap gives you the actual data about what's there

[shrewd shoal]

other returns an array

I see

ok will try check box

also doesn't box cast all or any other raycast all return the one that it starts in as well?

[timid dove]

no

[shrewd shoal]

I swear there was one that did that

[timid dove]

but you can try it if you don't believe me

[shrewd shoal]

according to the unity docs no it doesnt

I swear when reading somewhere when I tried to lookup the difference between raycast, raycastAll, and raycastNonAlloc one of them did that

anyway beyond what I need

[timid dove]

Maybe you're thinking of Physics2D.Raycast ?

[shrewd shoal]

never worked in 2d so idk

ok now it works on the ramp but not the flat ground lol

if (Physics.CheckBox(new Vector3(0f, -0.01f, 0f) + this.transform.position, size, this.transform.rotation, mask))

so I combine both for the fix

even when removing the first vector3 that I add to the transform.position

[timid dove]

use the DrawCube thing

[shrewd shoal]

didn't have to change anything about it because the values are the same

[timid dove]

show the full code now?

[shrewd shoal]

float ExtraDistance = 0.50f;
Vector3 size = new Vector3(0.5f, 0.01f, 0.5f);
if (Physics.CheckBox(new Vector3(0f, -0.01f, 0f) + this.transform.position, size, this.transform.rotation, mask))
{
      //hit something
      //Debug.Log(raycastHit.collider.gameObject.name);
      return true;
}
else
{
      //did not hit anything
      Debug.Log("No Hit");
      return false;
}

[timid dove]

why no log in the positve part of the if statement?

And can you show the draw cube part too

[shrewd shoal]

private bool CheckGround()

if (CheckGround())
            {
                Debug.LogError("IsGrounded BUT NOT");

wait think I solved it, just added extra distance to the boxes y to make it reach enough

[timid dove]

oh god yeah you made it absolutely tiny 🤔

i wasn't even paying attn to the size

[shrewd shoal]

now the only issue I have is that when jumping on the ramp it instantly puts you back drown because it collides with the side

hmmm

[timid dove]

make the box less thick?

Or use CheckCapsule instead?

[shrewd shoal]

well the original reason I was doing this was because I didn't like the way that the character controller was doing its ground check because it would bump the player when walking off an edge

mainly because the collider is a capsule

and they have those rounded edges

would rather it be more either your off or on the platform, not partially off sliding down the side

tried to hack together my own character controller but it was way to confusing, (just kinda wish the character controller wasn't forced to a capsule but I guess its that way to make physics math easier or something)

so I mean if I could do a disk or something that way its round like the collider well being flat would work

[timid dove]

that's fine you can still have a capsule shaped ground check but leave your collider as a box

[shrewd shoal]

yea but the unity built in character controller is forced to a capsule

so unless I can program my own or use the asset store im kinda out of luck

[timid dove]

but you're not using the CharacterController

are you?

[shrewd shoal]

I am

[timid dove]

oh

ok but still

why not use a capsule for your ground check

just... one that's positioned slightly offset down from the CC capsule

[shrewd shoal]

Heres how my gravity works, when the player is not detected as on the ground it applies a downwards force on the player, the problem with having a ground check in the shape of a capsule is the rounded ends of the capsule, if the player goes far enough off the platform and the curve is away from the platform the player will be detected as not one the ground, the forces will be applied and the player will be moved down (until they are detected as on the ground again) which would happen almost instantly because of the small curve, this would cause the player to move down very slightly can cause the edge walking up and down im talking about

here ill make a mock up in paint

[timid dove]

you're trying to basically hack the shape of the CC to not be a capsule

Probably should just go ahead and use a RB based character controller and use whatever collider shape you want

[shrewd shoal]

yea probably

what im saying is this

basically what I was trying to do is have the ground detector not curve away from the ground that way the player doesnt fall until they are fully off of the platform

[timid dove]

yep I get it

[shrewd shoal]

yea imma go look into controllers that hopefully can achieve what I want

[timid dove]

and I think this is the answer

[shrewd shoal]

well thanks for the help, I appreciated it.

[stuck bay]

it looks like you shoul not use a capsule for this

a box would be better

[shrewd shoal]

already decided to look into other character controller options

[obtuse seal]

Hi, not sure if this is the right channel but for some reason my hitbox isn't working as it should, first picture shows the actual hitbox and the second one shows what happens when I run the game:

you can clearly see a gap there and when I build the game and run it in fullscreen it's even more noticeable

settings my hitbox to 0.93 size fixes it but I can't do that since the game will be something like geometry dash where it should be precise

[iron wing]

Hey thanks for your answer! I tried it and it seems to work, but it's really janky, do you have any idea how I could make it smooth?

Also for some reason, the joints are immovable, how could I achieve that?

[iron wing]

Go to Edit--> Project Settings--> Physics2D, there change the 'Default Contact Offset' value to something smaller, it should fix it :p

Though be careful not to put it to the minimum, because high velocity objects could glitch through

[sinful girder]

Can anyone help me my character controller is making this happen

when i go to an edge of a block this happens

[iron wing]

How do you manage the falling & idle animations?

[split wedge]

Can't seem to figure out why, despite my sprite having a Polygon Collider 2D component, the IgnoreCollision function just says that the collider is null.

ignore this, unity decided that it wasn't an issue when i restarted it 3 times

[timid dove]

Show code

[split wedge]

As previously mentioned, Unity decided that it wasn't null after I restarted it three times.

Thanks for trying to help though.

[compact sphinx]

is there a script i can use for gravity and jumping?

also, how do i import a map
?

[timid dove]

Start with some tutorials

[hushed lava]

Hello peeps! I am working on a racing game and I need some help simplifying car mathematics.

I've never been good with math and looking at tutorials online cloud my mind but are also way, way too complicated for my purposes. I have a list of behaviors from the player's perspective and I could use some some help turning it into variables and functions. Note that even if I write speed or acceleration, I may not mean the **ACTUAL **speed or acceleration.

1. Car starts from 0 "speed". In this game, unless the player is hitting the breaks, the car speeds up on it's own.
2. Car has constant mass + only travels forward in X axis and does not rotate in any axis.
3. Wheels are purely cosmetic, you can think of the car as a box for intents and purposes.
4. There is wind resistance (which is why I assume planes don't accelerate towards infinity).
5. There is also road resistance. If the car jumped off a ramp, the road resistance doesn't influence the car so it's "top speed" increases. Landing, it would slow down to it's normal top speed "on land".
6. If the car drives over an + pad then it goes faster, even if it was at "top speed" before it went over it. Escaping it will slow it down back to normal top speed. It feels to me like this is like an opposite effect of wind or road resistance.
7. If a car **hits **an object, it's current speed (and acceleration?) decrease but then goes back towards the top speed.

Finally) Gameplay wise, I have a property called Power which at 0 or below, the car will run at default speed and the more points the player puts into Power the faster the car accelerates and the higher it's top speed reaches. The values do not matter really, simply consider that each point adds a +1% or whatever.

[timid dove]

Sounds pretty simple honestly

You just have a maxSpeed which the current speed is always accelerating towards, and just based on the conditions in the game you change maxSpeed

Not much more to it

[hushed lava]

I have been trying, but my car reaches thousands in velocity, I can't replicate that Need for Speed energy I am chasing

[timid dove]

Just clamp the velocity to the current max

https://docs.unity3d.com/ScriptReference/Vector3.ClampMagnitude.html

[hushed lava]

I don't want to have maximum speed written by hand, I want it that once it reaches a speed high enough it can't go past it due to what I assume is increasing air resistance and more powerful land drag

[timid dove]

Then add wind and drag forces

Proportional to the current speed

In the opposite direction of movement

Everything is just a force

So treat it that way

[hushed lava]

My current code I am tinkering with.```
public class VehicleCarPhysics : MonoBehaviour
{
[SerializeField] protected float friction = 0.05f;

[SerializeField] protected float acceleration = 0.1f;

[SerializeField] [ReadOnly] protected Vector3 velocity;

void Update()
{
    bool isBreaking = Input.GetKeyDown( KeyCode.Space ) || Input.GetKeyDown( KeyCode.S ) || Input.GetKeyDown( KeyCode.DownArrow );

    if( isBreaking )
    {
        DoBreaking();
    }
    else
    {
        Accelerate();
    }

    transform.position += velocity * Time.deltaTime;
}

private void Accelerate()
{
    float deltaTime = Time.deltaTime;

    velocity.x += acceleration * deltaTime;
}

private void DoBreaking()
{
    velocity.x *= 1f - friction * Time.deltaTime;
}

}

[timid dove]

Your Accelerate() function is just a force

Air resistance is just a force

It all can work the same way

But you could also just use Rigidbody

And literally use AddForce

[hushed lava]

So simulating drag would be velocity.x *= 0.9995f or something like that?

Not using rigidbody

[timid dove]

I know you're not, but you could

And probably should

[hushed lava]

it's a dots project and my car is kinematic

[timid dove]

There's physics packages for DOTs

But anyway

#⚛️┃physics message

[hushed lava]

So air resistance should be stronger the faster the car goes, right?

velocity.x *= 0.9995f ?

or do I do something like velocity.x *= ( airResistance + groundResistance) ?

[chilly cave]

            if (transform.position.y <= 1.070f) {
                Vector3 newPosition = new Vector3(transform.position.x, 1.070f, transform.position.z);
                transform.position = newPosition;
                this.rb.useGravity = false;
                if (Input.GetKeyDown("space")) {
                    rb.AddForce(0, playerJumpForce, 0, ForceMode.VelocityChange);
                }
            }
            else if (transform.position.y > 1.070f) {
                this.rb.useGravity = true;
            }

Is it just Unity things that this doesn't actually keep my object at or above 1.070 at all times, or is there a better way to code it so it will? If I jump, when I come back down the object goes to below 1, even though this script should not allow that, and then my jump doesn't work properly as a result. Very annoying.

[viral ginkgo]

@chilly cave Looks like the gravity builds up some y velocity on your object

When it hits the 1.070, you might wanna reset the y velocity

But I wouldn't do any of this

Just let the physics stop your character

Or don't use physics and simulate your own velocity if you are doing a very simple game

[karmic glade]

Hey! I want to get a vector that goes in the direction of this spheres normal (normal is shown as the arrow) all the way to the plane. What is the best way to do calculate this? I do not want to use raycasts. I want to be able to rotate the sphere, change it's position as well as rotating the plane and changing it's y cord

[timid dove]

You're not zeroing out the y velocity

[timid dove]

Wdym by the spheres "normal"?

Spheres don't have a normal.

[karmic glade]

it is it's forward normal, which is the direction I want it to go

[timid dove]

It's not a normal, wrong term

It's just transform.forward

[karmic glade]

alright, but it is a normalized vector? 😉 but I guess wrong term

anyways, so what I need is the distance from the sphere toward the plane in the direction of the normalized vector that you can see in the picture as a red arrow. Can't you calculate this by doing the cross product of the planes normal with something?

[timid dove]

Use Plane.Raycast

It's a math only thing

No colliders involved

https://docs.unity3d.com/ScriptReference/Plane.html
https://docs.unity3d.com/ScriptReference/Plane.Raycast.html

[karmic glade]

as mentioned above I do not want to use raycasts as they are ineffective

[unique cave]

As mentioned Plane.Raycast doesn’t involve any colliders and stuff. Plane.Raycast is super cheap. You can’t really compare Physics.Raycast and Plane.Raycast together in terms of performance. Plane one should be magnitudes faster

This is what Plane.Raycast does under the hood

[timid dove]

What do you mean by "ineffective"? Your only quarrel with my method is the word "Raycast". It does exactly what you're asking for.

As you can see from Aleks, it's literally just some math.

[karmic glade]

ah sorry, That is exactly what I need then! Thanks a lot for the help ❤️

[hushed lava]

Hi! Anybody want to take another whack at this? I am currently trying to figure out how to calculate air/ground resistances based on acceleration or current velocity in order to naturally cause a top speed without clamping velocity at a fixed top_speed :/

[carmine basin]

Drag is directly proportional to velocity squared

let me find the drag equation for you

In this case you could ignore area, or just take the value as 1 to simplify it

for example, in unity, it could look something like this

float dragCoefficient = 1f; //A drag coefficient. This might also be better as a static but it is your choice.
float airDensity = 100f; //The density of the air. Might be better to make this a static.
Rigidbody vehicleRigid;
  void CalculateDrag()
{
  dragForce = dragCoefficient * ((airDensity * vehicleRigid.velocity * vehicleRigid.velocity) / 2)
  vehicleRigid.addForce(-vehicleRigid.velocity.normalised * dragForce);
}

lemme fix this rq

[hushed lava]

We want dragCoefficient to be something like 0.99995f right?

[carmine basin]

I believe so

[hushed lava]

Can we collapse dragCoefficient and airDensity into a single value?

considering that it's all multiplications

[carmine basin]

The drag coefficient refers to the effectiveness of streamlining of the vehicle

so a cube would have a dragCoefficient of 0.99 for example, while most modern cars seem to have one between 0.25 and 0.3

[hushed lava]

ah, since I am trying to simplify the math considerably, I will consider it to be 1, thus, neutralized

where would I put deltaTime in here?

[carmine basin]

I don't think setting it to one is a good idea for cars

It'll be too high and super unrealistic

[hushed lava]

I am using DOTS and my cars are Kinematic, they are more alike rollercoaster carts. There will be zones of acceleration and deceleration ,which I am treating as Resistance and "negative resistance"

[carmine basin]

Even an SUV has a max drag coefficient of roughly 0.45

[hushed lava]

@carmine basin If I am to combine several drags together, would I do something like dragCoeficient * ( airDrag + groundDrag + .... ) * ( velocity * velocity / 2 ) ?

[carmine basin]

If you combined the drag of the two you would do (equation for air drag) + (equation for ground drag)

So your final drag force for the air would be added to your friction force from the ground

I'm not sure how that'll act but it should be alright

It might even give you more stable behaviour than just one or the other

[hushed lava]

so in my FixedUpdate loop, what I am finally doing is EngineForce + AirResistanceForce + GroundResistanceForce + SPEEDUP_Force + SPEEDDOWN_Force right?

[carmine basin]

That sounds about right, yeah

If it gives you unexpected behaviour, tweak the values some

[hushed lava]

@carmine basin Thank you very much, this has been extremely helpful and informative ❤️ ❤️ ❤️

[carmine basin]

im glad i could help!

[hushed lava]

Hours of attempts at finding answers online and playing around with Unity formulas on my part

[carmine basin]

Its always good to look at the irl physics for how you'd achieve something.

since unity acts like the real world does at the basic level (minus the conservation laws), it should be a case of following the real world counterparts

[hushed lava]

If it was just about vanilla irl physics I would probably use a framework or something, but I wanted a greatly simplified system for the player to understand

[carmine basin]

that makes sense

[hushed lava]

My game is a Dungeons & Dragons-like game disguised as a racing game 😄

the drivers are the adventurers and the cars / car parts are the equipment

[carmine basin]

remember that physics exists in real life too lmao

[hushed lava]

yes but like I said it works more like a rollercoaster ride, so mass, torque, drag coefficient and many other things are 1, constant or don't exist. even the wheels are cosmetic only

[sinful girder]

can anyone help me i think it is wrong with the character controller

[carmine basin]

are you using a rigidbody?

@sinful girder

[sinful girder]

nope

[carmine basin]

oh, its stuck against a wall?

Or is it the fact it looks like it's jumping?

[sinful girder]

no when i jump onto near objects its stuck

[carmine basin]

Hmm, that's odd. Is that using the normal character controller?

[sinful girder]

yep

[carmine basin]

I'm gonna have to ask you to hold on till somebody else can answer that for you. I never used the character controller

[sinful girder]

okay

[chilly cave]

I'm trying to make an endless runner that uses physics instead of rails to do the motion, but I'm coming to the realization that Unity's physics fucking hate that idea. The cube hits the front face of my infinitely generating tiles despite the fact that face isn't exposed and shoots the cube into the sky, so I did this dumb hover shit to counteract that and now I have this problem. It's making me want to scrap the whole project.

[viral ginkgo]

@chilly cave oof

there might be some ways to deal woth that perhaps
just because thats a common issue i may also have heard here before

[chilly cave]

yeah everyone's suggestion was to hover the cube over the ground instead lol, which was fine because I want to add particle effects to make it look like it's sliding through a thin layer of snow on ice, so covering up the gap was totally within scope. I'll try making sure the y velocity 0s out though, I hadn't thought about that, I just assumed setting the position would do that for me.

[viral ginkgo]

@chilly cave yeah thats gotta be y velocity

that'll surely fix it

[carmine basin]

If you don't need to move up or down, you can always fix the y position of the rigidbody

[chilly cave]

YESSSS that fixed it, it's working perfectly now. Thanks a lot

[viral ginkgo]

no probs

[chilly cave]

I want to have jumping, so I gotta have up and down. I plan on having obstacles in the air and holes in the platform to avoid as well

[sinful girder]

can anyone help me with my problem

[real harness]

hi, I have flying drones (not affected by gravity) that I want to move from point A to point B in a "smooth" manner while still reacting to forces - roughly this velocity/time diagram, so kind of like a car accelerating, driving at constant velocity, and then abruptly braking

what unity tools would I use to best make it react to other objects too? e.g. a guy kicking the boston dynamics robot, it slightly straying off path, but ultimately still moving towards point B

(of course the robot is walking, while I just want smooth motion)

[jovial wraith]

I don't think Unity has anything built in to do this all on its own. You'd need to write a rigidbody based controller that uses AddForce to control the drone, not setting its position or velocity directly. Essentially a script tries to predict the correct force needed to get the drone flying on the desired path and calls AddForce every frame to apply that force.

[unique cave]

The formula unity uses is something like velocity -= velocity * amountOfDrag * Time.fixedDeltaTime (I think it also has to make sure it never overshoots which would make it jitter when it’s about to stop)

[carmine basin]

I'm honestly not sure. I never have problems with objects moving over between mutliple surfaces. Double check to be absolutely sure that all your y positions are zeroed on your objects

[chilly cave]

Thank you, but another user helped me solve it before I said that 😄

[carmine basin]

ahh, awesome!

what was the bug?

[chilly cave]

I had to set the y velocity to 0, because gravity was pulling it down it was getting set to 1.07 but then moving slightly downward again and not being moved back up.

so now it works perfectly, jump throws the cube upward and when it gets back down to 1.07 it stops falling and doesn't collide with the ground just as I intended

[carmine basin]

Ahh, i see. That's always a problem

I think, at least

you're making a runner, did you say? like temple run kinda thing?

[chilly cave]

I'm learning that assumptions are my biggest enemy every time I find an issue with something I've coded, I need to get into the habit of checking into any assumption I make to make sure it's actually true

yeah, basically it's an ice cube sliding down an endless glacier, with obstacles to dodge and powerups/points/etc to collect

so I wanted to use physics to make it fun with the cube sliding around and spinning/flipping, instead of just sliding on rails with an animation

[carmine basin]

I am curious as to how you're handling the whole infinity thing

Are you using DOTS and some trickery in that, or floating origin or something?

[chilly cave]

I'm not sure what DOTS is, but the cube is constantly moving forward and as it goes the platforms you leave behind are deleted, then new ones are spawned to replace them. I haven't gotten to the point where it's an issue yet, but I read somewhere that I can just transform everything all at once backwards before it hits the engine limit for z so I was probably going to look into that

[real harness]

thanks, I guess that would be more of a ForceMode.Acceleration vs ForceMode.VelocityChange, right?

[timid dove]

You're thinking way too simplistically. You need a PID controller

[violet tapir]

im having an issue causing my character to slide backwards and to the right. I have tested multiple movement controllers so i know it isnt the code. I have checked the gravity setting and theyre all fine so i have no idea what could cause this issue. I have a video of this issue occuring https://youtu.be/SbpPNHkO_9o

[timid dove]

Do you have a gamepad or joystick plugged into your computer?

[violet tapir]

ah yeah i have a hotas

hadnt considered that

ill go test it rq

yup that worked lol

[violet tapir]

thanks

[carmine basin]

what's a pid controller, people keep mentioning them

nvm googled it

[stuck bay]

Ok, not sure if this is the right channel for this but I'm really angry right now because for some reason when I give my blender imported model the navmesh component so I can make an AI for my game my model resets its rotation and doesnt work like on a normal cylinder or something. I think its because of the shitty axis conversion on blender and unity so when my model is standing upright its x rotation is -90. I've tried finding an explanation and giving it to my friend who makes the models, and he says I have to fix it on my end on unity. Can you help me out?

[honest rock]

anyone know the name of the physics they use on the feets? i'm looking for a tutorial

[viral ginkgo]

@honest rock IK

interkinematics

where you declare a target position for feet

and the limb rotations in the leg figure themselves out

[honest rock]

thankkss

[timid dove]

Yep your models rotation is All wrong. The blue arrow should be its forward direction and green should be up

Go back to blender and fix it

[bleak umbra]

Maybe this helps

[wraith crescent]

in 2D do i need a rigidbody to have collisions cause right now nothings colliding but when i add a rigidbody to an object they do but then they have gravity

[real harness]

check the component, there should be a "Gravity" checkbox you can untick

[wraith crescent]

i dont see that one the 2D version so i just disabled it in the physics tab

[real harness]

TIL

[timid dove]

There's a gravity scale on it

You set it to 0

And yes you need Rigidbody for collisions

[prime flower]

Physics-based volleyball messing with first person

It's always a challenge starting with rigidbodies and pure physics, and then trying to lay visuals and animations on top of that

doing it mostly with Final IK

[supple sparrow]

Looks great

[chilly root]

how do you give a physic body to a mesh

[timid dove]

Rigidbody and colliders

[chilly root]

thx

[atomic garnet]

I'm trying to make a wall jump but I'm having an issue with colliding with walls. Whenever I collide with the wall a couple pixels stick into it making it so that I stick to the wall when I want to have the player slide down it. I'm assuming this is a collision issue because sometimes it works. Please help.

[cyan totem]

I've got a Rigidbody 2D question I can't find clarity on. If I have a gravity scale of 1, a mass of 1, and I apply a force of (0,100), will it have the same effect as a grav of 1, mass of 2, force of (0,200)? What about a gravity of 0.5, mass of 1, force of (0,50)?

In other words, is there a net effect to adjusting all these numbers, other than appearance? When starting a new project, is there any logic around what values to tweak, or do you tweak all 3 to get the effect you want? Feels like I'm overcomplicating things and I don't know which numbers to fiddle with. >_<

[modest cape]

what does this mean

[neat coral]

I would simply try to use real world values to start with

Should give you a reasonable result

Then you can tweak it as you need

[zealous schooner]

i need help setting up a body system similar to gorilla tag, with the head and arms. i already have the movement mechanics done. i just want to give the players a design so it’s not just hands

[proud crater]

Does anyone have thoughts on how to decouple top speed and acceleration? Our game has vehicles that should have varied top speeds and acceleration stats.

If I do something like:
rigidbody.AddForce(forwardDirection * baseEngineForce * Time.fixedDeltaTime, ForceMode.Acceleration);

...then the object naturally accelerates towards a top speed based on the amount of force. My first thought was to use acceleration as a multiplier for baseEngineForce, and use top speed to clamp the rigidbody's velocity. However, this also prevents external forces (i.e. driving over a boost panel) from exceeding the top speed.

[prime flower]

if you're talking about having more natural acceleration like a car, you can try something like Rocket League does, where you basically decrease the acceleration force as the car gains forward speed

if you decrease the force down to a minimal amount or 0 towards a high end, that will act as a top speed

[neat coral]

smart

[rustic jacinth]

Hello!
I'm trying to attach silly ragdoll hands with a spring to my character rigidbody

But the hands keep pushing the main body around while they're flapping. How can I make them not do that?

[proud crater]

So basically, decrease the acceleration force once velocity reaches a certain threshold? Makes sense

[neat coral]

layers

[rustic jacinth]

Yea, already tried it

Also, is there a joint that works just as a spring but has no min distance?

The spring min distance makes the hand rotate around itself sometimes. I just want it to bounce back into position when the main body moves abruptely

[modest cape]

Any1?

[timid dove]

i'd guess your mesh has messed up/broken geometry that the physics engine can't figure out how to build a collider from.

[modest cape]

it's a cilinder, thats not to difficult is it?

[timid dove]

shouldn't be but depends on how you made it and what you may have done to it afterwards

[modest cape]

yeahh... its so much i dont even know anymore

[prime flower]

Yes but you also want to decrease it as velocity increases. otherwise you’ll have a constant acceleration which is not very car-like

[upbeat wave]

I have a parent(rigidbody2d, kinematic, interpolation) which is moving with rigidbody2d.velocity (child aswell, inherited velocity) and a child (rigidbody2d, kinematic, interpolation) which on trigger moves half speed through rigidbody2d.moveposition. But while the child is moving half speed it is stuttering a lot. Any workaround for this ?

[bleak umbra]

In most cases you should not modify the velocity directly, as this can result in unrealistic behaviour - use AddForce instead Do not set the velocity of an object every physics step, this will lead to unrealistic physics simulation. A typical usage is where you would change the velocity is when jumping in a first person shooter, because you want an immediate change in velocity.

[bleak umbra]

Also if you have a kinematic rigidbody, forces will do nothing and setting velocity is not the way to move it.

[stable cypress]

Hi guys

I have a question, if for example if we give a complex object a Mesh Collider, do we have a frame drop before it collides with it or is it being processed before the collision? For example, there are 100 objects in the scene with Mesh Collider, but we may not collision with them at all

[viral ginkgo]

@stable cypress It looks like your game is at the frame after the collision has happened

In other words, when you are in an OnCollision callback, the collision has already happened

https://forum.unity.com/threads/get-positition-of-moving-object-right-before-collision.885241/
https://docs.unity3d.com/Manual/ExecutionOrder.html

What do you wanna do anyways

[stable cypress]

In a big city, there are some objects that we may not collision at all, such as the top of the billboard, but it is not possible to use all of them manually in the Box Collider, and it takes a long time.

[upbeat wave]

The parent is moving continuously in one direction with velocity added at the start and all child follow the parent. Just a few on trigger should change velocity, but only those and at that specific time so i tried to manipulate the children ontriggerenter with moveposition.
The velocity isnt the problem, all objects moving very fine only when im starting to overwrite the velocity with moveposition stutter occur.

[bleak umbra]

the clue here is that you are using physics all wrong. if you manually move your objects via kinematic rigidbodies you should NOT use any property of a rigidbody that is based on non-kinematic (simulated) physics (like velocity & forces) and you should not nest rigidbodies while doing so. If you need to simulated connected rigidbodies that more relative to each other, you would use Joints.

[primal pivot]

Hi folks 👋 . Wondering if anybody here has a good setup / code for golf ball physics? Specifically the behavior of the ball sliding on ice?

I have most of my physics sorted - but need a way to have the ball transition from rolling to sliding on the ice. Any ideas?

And yes, I've already tried Physic Materials, and these don't suit, unfortunately.

[viral ginkgo]

@primal pivot Have you disabled the default angular velocity limits?

Maybe it's better than you think

I think what you want should be doable via playing with these:
dynamic friction multiplier in physics material,
static friction multiplier in physics material,
inertia of the ball

If not, I guess you could disable rigidbody rotation and all friction.
And simulate rolling yourself

[primal pivot]

Yes, I have. And unfortunately, that doesn't help. The behavior I'm looking for is that when the ball encounters ice (say, from a grass environment it moves to ice on the course), the ball slowly stops rolling, while at the same time continuing to slide. I have some of the solution already (the bit that can freeze the mesh, rather than the rigidbody) ... I'm just needing some help to get the "transition" looking right. That is, to have the rotation slow down visually (i.e. the mesh) until it comes to a "stop", while the rigidbody keeps behaving as normal (and likely using Physic Materials and custom Newtonian calculations for friction interactions, since Spheres don't behave correctly with PhysX because they are essentially a "point")

[viral ginkgo]

Hmm you want to fake the physics of this?

Hmm

If* I was implementing the physics of this but in simpler manner

1- I'd have a ground velocity
2- And I'd have the linear velocity of the ball on the ground

Both in ground plane space (2d)

I'd do the static/dynamic friction between these two velocities

I'd sum up the velocity differences that happened to the #2
and use them to find a vector3 linear/angular velocity change to the ball

[primal pivot]

The velocity piece I have solved with actual Newtonian calculations (they aren't that difficult to implement). What I'm struggling with is the animation piece of controlling the mesh (i.e. the visual component) in a way that makes the slide more obvious. For example, I have a Rigidbody parent with another Rigidbody as a child. This child RB has its rotation frozen so it can be manually controlled, and changes its rotation based on Quaternion calculations and offsets relative to the parent RB. What I need is a way to gradually transition (probably via a Lerp or Slerp of some sort) from a "rolling" state to a "sliding" state. That is, the Parent RB continues as normal, but the mesh appears to be sliding rather than rolling. I hope that makes sense?

[viral ginkgo]

Why is there two parented rigidbodies?
Shouldn't you just need one?

I am guessing you can calculate the angular velocity of the ball with your calculation?

[primal pivot]

Correct.

[viral ginkgo]

You could just use that to rotate a static child ball mesh?

[primal pivot]

The child RB is necessary because freezing the parent RB results in incorrect physics.

[viral ginkgo]

why does the child need a rigidbody
hm

why freeze parent?

I'd image you'd be freezing only the rotations

[primal pivot]

Actually, scratch that. That was an earlier experiment (I've tried a lot of things!). You are correct. There is only one RB.

I am driving the transform of the mesh relative to the transform of the RB

[viral ginkgo]

parent:
rigidbody with frozen x,y,z rotation and zero friction

child:
mesh renderer, mesh filter

and parent has a script that rotates the child

[primal pivot]

    private void SetTargetRotationRelativeToSource()
    {
        if (sourceRigidbody == null || targetTransform == null) return;

        var sourceAngularVelocity = sourceRigidbody.angularVelocity;
        var currentRotation = targetTransform.rotation;
        var rotationDegrees = sourceAngularVelocity * (Mathf.Rad2Deg * Time.deltaTime * rotationRatio);
        var newRotation = Quaternion.Euler(rotationDegrees) * currentRotation;

        targetTransform.rotation = newRotation;

    }```

rotationRatio controls how much of the source's rotation is applied

[viral ginkgo]

source angular velocity should be zero all times no?

if you lock it

if you use your newtonian calculation, why is the rigidbody angular velocity relevant to you?

[primal pivot]

For this, you would lock only X and Z rotation, not Y rotation, since the ball could spin on its axis

The Newtonian calculations are for friction

[viral ginkgo]

the friction you find should be convertable to a delta in angular velocity and linear velocity

[primal pivot]

    private void SetFrictionVector(Collision collision, float frictionCoefficient, float rotationalFrictionCoefficient)
    {
        var surfaceAngle = Vector3.Angle(collision.contacts[0].normal,Vector3.up);

        // Ff = u * mg * sin(w)
        var frictionForce = _rb.mass * Physics.gravity.magnitude;
        frictionForce *= surfaceAngle == 0 ? 1f : Mathf.Sin(surfaceAngle * Mathf.Deg2Rad);

        _frictionVector = -_rb.velocity.normalized * frictionCoefficient * frictionForce;
        _rotationalFrictionVector = -_rb.angularVelocity.normalized * rotationalFrictionCoefficient * frictionForce;
        //_rb.angularDrag = frictionCoefficient;

    }

[viral ginkgo]

and that'd be the source of your angular velocity

[primal pivot]

frictionForce is applied in FixedUpdate:

    private void ApplyFriction()
    {
        if (_rb.IsSleeping()) return;

        _rb.AddForce(_frictionVector, ForceMode.Force);
        _rb.AddTorque(_rotationalFrictionVector, ForceMode.VelocityChange);
    }```

I'm not sure I understand your reasoning?

[viral ginkgo]

Hmm okay

so you have an angular velocity that you operate pretty much

[primal pivot]

Yeah, kind of ... however, I'm doing this by applying a force calculated by SetFrictionVector according to Newton's calculation

[viral ginkgo]

hmm but that angular velocity also rotates the gameobject parent

[primal pivot]

Ff = u x mg x sin(w)

[viral ginkgo]

So I guess this is not a physics problem

And If I understand correctly, your issue is you are using rb.angularVelocity

If you just use a plain vector3

and lock your rigidbody rotation

it can't mess with your parents rotation

[primal pivot]

If I do that, I won't know what the rotation should be?

Unless I literally do those calculations myself?

[viral ginkgo]

Quaternioun.Identity will be your first rotation

and then you'll do
rotation = Quaternioun.Euler(angularVelocity * constants) * rotation;

every fixed update

@primal pivot that might be wrong

but its just integrating the rotation with angular velocity

i mean that's what i meant

[primal pivot]

I think I understand - basically, calculating the rotation based on the angular velocity (i.e. how far it's moved) - which likely means taking into account the diameter of the sphere?

[viral ginkgo]

orientation += 0.5*orientation*angVel
might be something like this

[primal pivot]

And the friction of the surface?

Why the 0.5?

[viral ginkgo]

https://stackoverflow.com/questions/46908345/integrate-angular-velocity-as-quaternion-rotation
just pasted it from here

not sure about the maths tbh

[primal pivot]

Lol. That's the same article someone else pointed me to ... but I couldn't make sense of it! 😄

Maybe I just need to spend some more time with it and try to understand it?

[viral ginkgo]

@primal pivot I don't know how you may handle your other parameters

An angular velocity and a delta time should be enough to integrate a rotation

[primal pivot]

OK, thanks. I will have to dig deeper...

Appreciate the steer

[viral ginkgo]

no probs have fun

[prime flower]

More first person volleyball
https://streamable.com/c0644w

[versed shadow]

That actually looks really fun

[torn pivot]

Not sure if this is the right channel to ask, But how would I be able to have my character tilt on a slope instead of bouncing on it?

[versed shadow]

I think as long as the board and velocity vector is parallel with the slope that shouldn't happen

[torn pivot]

How would I be able to add a velocity vector? The board is only parented to the player, so there's not much on it except for a box collider

[prime flower]

you need to basically find the current contact point, find the normal of that, and then calculate a velocity vector using the normal

[dry sentinel]

would anybody be able to help me with this? I made a chain in blender and in unity am trying to make it have a rigid body so it can act as a chain, the only problem is that non-convex mesh colliders with non-kinematic rigid bodies don't work. And if I make it convex it kind of breaks the chain and sends it flying because their is no hole for the chains to interlink. Is there a easy solution to this other then manually compound colliders for it?

[timid dove]

Just make them use capsules and attach them with joints

[dry sentinel]

Hmm

I’ll see

Thanks

[timid dove]

It's really wishful thinking to think it's just going to work nicely by having actual correctly shaped colliders

[dry sentinel]

Lol

[versed shadow]

You could construct each link out of smaller colliders

But the joints will be a more performant option

[modern verge]

Hi, If i have physics.simulate called on two different prefabs' scripts each fixedupdate, does it make both of the prefabs call twice as often therefore move twice as fast?

[timid dove]

conversation in progress on this over here #archived-code-general message

[unique cave]

If you’re going to use this in actual game, that may not perform well enough (and even if it did, the chain is going to break if it’s long enough or otherwise too large forces are applied to the chain). Joints are better for performance but they obviously doesnt give that accurate simulation. For fun test, using capsule colliders is fine option.

[timid dove]

I think not using joints is just going to end up with the chain breaking pretty much immediately due to tunneling

[versed shadow]

I thought unity collisions would be a bit more sophisticated than that

But that would only make the performance worse anyway

[unique cave]

That’s not really that long chain so it may survive. Tried exactly that type of chain few weeks ago and it worked surprisingly good. Tunneling only happeneded after making quite long (maybe 2-3 times longer than that) chain

[unique cave]

Exactly physx is meant to be cheap way to calculate physics realtime. Anything much more realistic than that would be really heavy to calculate

[versed shadow]

I was wrong anyway Unity does have continuous collision detection that eliminates tunnelling

[unique cave]

that doesn't help at all in this case

[versed shadow]

It should do, that's the sole purpose of continuous collision detection