⚛️┃physics

[summer fog]

if you update 10 times a second

I think that's right

🤔

[frosty ore]

i run it in the fixed update for now

well i said addforce

[summer fog]

disregard my comment about how frequently

[frosty ore]

i gues im using velocity

lol

[summer fog]

oof

well

modifying velocity is fine

[frosty ore]

i mean it feels ok

[summer fog]

just don't modify position

[frosty ore]

yea yea.. i gotcha

i realized after i bought this controller

it has an array of raycasts and it positions itself above the ground

instead of using the regular gravity only when its not grounded does it use gravity

so i gotta make do if i want it to interact with anything beneath it :smh:

[summer fog]

if you want to simulate a 1kg object

it should apply a force of 9.8

every tick

[frosty ore]

makes sense..

ill just take the gravity variable fromt he physics system and multiply it by my weight instead of using magic numbers

[mighty sluice]

or you could just use acceleration mode

ForceMode.Acceleration

[frosty ore]

ill give that a try too 👍

[mighty sluice]

gravity is an acceleration that applies equally to all masses

[frosty ore]

right now im just brainstorming something that isnt gonna break later on lol

right now its still kinda funky when u walk to the edge of something thats physics based

but thats just my overlap sphere i think..

i think i fixed her up.. we'll find out

[vapid tusk]

I need to get the velocity of a game object. Can I get the velocity of a game object, directly from the game object or the Transform, or do I need to have a RigidBody on the game object in the scene, to get Unity to give me game objects's velocity?

[sweet snow]

You need a rigidbody to have velocity.

[vapid tusk]

@sweet snow Thank you.

[stuck bay]

@lost hornet how you doin?

[wide nebula]

!warn 847765690513358849 Don't tag/disturb random users.

[flint portal]

Jerry/GameDev#2678 has been warned.

[stuck bay]

!warn

no

Sorr

y

[wide nebula]

Don't spam please. Just move on.

[stuck bay]

ok

[stuck bay]

can i post that here?

[abstract aurora]

Hey do stuff like collision events in scripts get called between 2 layers that aren't set to interact with each other on physics menu? ( basically is the physics menu only for rigidbodies or its for all script interactions as well ? )

[shell adder]

collision events rely on rigidbodies so i think the physics menu applies to them as well

Collision events are only sent if one of the colliders also has a non-kinematic rigidbody attached.
https://docs.unity3d.com/ScriptReference/Collider.OnCollisionEnter.html

[abstract aurora]

ok well my question is still about physics layers though

[shell adder]

yeah so anything that has a rigidbody or relies on rigidbodies, will follow the physics layer menu

[abstract aurora]

oh i see ok thanks

[stuck bay]

Hi all. I have a pretty simple question - I'm working on a car game with my girlfriend just for fun, and I'd like to add "destructibles" such as lamp posts, benches, bins, etc... I already know how to get collision and rigidbodies working just fine to get most of the effect going, but I also need a way for the objects to stay in their correct spot until the car crashes into them. Like the lamp posts, those just fall over when I play the scene. Am I missing a simple and obvious checkbox or option somewhere, or do I need a script? Or something else entirely?

[ruby prawn]

Why when I activate the interpolation on a rigid corp the corp may fall at blocking lapses?

[wide nebula]

One option is to turn off gravity for that object. When you collide with it, turn gravity on.

[stuck bay]

@wide nebula Well that's what I'm trying to achieve, but how? Is there a toggle or do I need a script?

[wide nebula]

You can see the gravity on the on the rigidbody component's inspector. You can access this in code and setting it to true or false.

[stuck bay]

So there's no simpler way than a script.... 🙁

[timid dove]

Read what he said again

But in order to switch the gravity on collision yes you will need a script

[stuck bay]

Well I know about the toggle, but how do I make it switch state on collision? Yes, I'm pretty dumb

Ah. Yeah there we go.

Well, thanks

[wide nebula]

Look up how to use GetComponent, which you can use to grab the rigidbody off the object you're colliding with. Then from there set the bool to true.

Not the cleanest way to handle it, but it's beginner friendly.

[stuck bay]

Hi.

[wraith flame]

hi

[wraith junco]

Anyone here ever make a rigidbody helicopter or airplane?

[vocal charm]

guys can someone direct me into the correct channel cause i wanna make a 3d character controller using pureley raycasts

[shell adder]

i think here or #archived-code-general would be fine

[vocal charm]

ty

[timid dove]

I made a drone

[timid dove]

https://www.youtube.com/watch?v=Tcf6Kafs4Ro

[stuck breach]

I can't send colliders . Why?

[timid dove]

Collider and Collider2D are different

[stuck breach]

True thx

[stuck bay]

How do I fix this? As you can probably tell, I can't code

I copied this from a thread I found where it was OnTriggerEnter, but I'd like to use it on collision instead

[wide nebula]

There's nothing wrong with it.

Make sure your collider isn't set to be a trigger.

[stuck bay]

In the inspector for the object? It's not set as a trigger.

This is the problem

[wide nebula]

Right, sorry, the parameter is type Collision.
https://docs.unity3d.com/ScriptReference/Collider.OnCollisionEnter.html

[stuck bay]

Oh I see. Sorry, I know just about nothing about coding. Thanks

[outer shadow]

I'm trying to have the bullet that the player fires collide with the walls the same way it collides with the enemy (white character) , any tips?

this is my code for it

[timid dove]

Why not just do:

void OnCollisionEnter(Collision other) {
  Destroy(gameObject);
  Instantiate(poopPart, transform.position, transform.rotation);

  if (other.gameObject.TryGetComponent(out EnemyHealthManager ehm) {
    ehm.HurtEnemy(damageToGive);
  }
}```
e.g. ALWAYS do the particle thing and the destroy thing, and just do the damage enemy thing if you hit an enemy.

This way you don't repeat your code.

[outer shadow]

thanks, the bullet still doesnt get destroyed when it collides with the walls however

[timid dove]

Well one problem is you're using Transform.translate to move the bullets which ignores physics

another problem is that, for a collision to happen:

• Both objects need colliders
• One of the objects needs a Rigidbody
• Neither collider can be a trigger

I suspect you don't have a Rigidbody on the bullets or the walls

so there's no collision

If you don't have a rigidbody on a collider, it's considered a static collider, and Unity doesn't expect static colliders to move.

[outer shadow]

how should I go about changing this? fairly new to programming not exactly sure what to do

[timid dove]

I just explained what you need in place to get the collision to happen

You need to modify your GameObjects to satisfy those conditions

It's not even really a programming problem

[outer shadow]

thanks got it working now 🙂

[wary ferry]

so I have a Tilemap with a Platform Effector, Rigidbody2D (static), and a Tilemap Collider 2D on it, but for some reason when my player jumps and then lands on top of a tile, it takes a second for it to realize that it's on the ground. I check if it's on the ground by calling a raycast from the character straight down and seeing if it hits the ground, but for some reason I guess it takes a long time to complete it. There shouldn't be any problems with my script, as I tried it on a GameObject with just a box collider 2d, platform effector, and a static rigidbody and it worked exactly as it should. Anyone know why this could be happening?

[timid dove]

raycasts happen immediately

Maybe share a video/code of what you're seeing?

[wary ferry]

I'm not at my computer rn, but basically in FixedUpdate I call a raycast straight down, and if it hits something it sets "isGrounded" to true. Looking in the inspector, isGrounded isn't set to true until maybe a second after touching the ground. Not sure what specifically I can mention that would be important, but I can send anything once I get back

[timid dove]

It's really impossible to say without looking at the project. The raycast might not be in the right spot, it might not have the right distance, it might not be using an appropriate layer mask, who knows.

Could theoretically be an Update/FixedUpdate timing issue

¯_(ツ)_/¯

[wary ferry]

Yeah I'll send a video and code once I get back, hope fully that will help

I'm just confused why it works fine on a single game object but gets messed up on the tilemap

[stuck bay]

for some reason, the force increases itself alone, any idea why?

[timid dove]

not without seeing your code

[stuck bay]

public class HumanLauncher : MonoBehaviour
{
    public int Force;
    public static Rigidbody Player;
    public static Transform Clown;
    // Start is called before the first frame update
    void Start()
    {
        Force = 170;
        Player = GetComponent<Rigidbody>();
        Clown = Player.transform.parent.parent.parent.parent.parent.parent.GetComponent<Transform>();
        RagDollOff();
    }

    // Update is called once per frame
    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            Clown.SetParent(null);
            RagDollOn();
            Player.AddForce(Player.transform.up * Force, ForceMode.VelocityChange);
            
        }
    }

    void RagDollOn()
    {
        foreach (Rigidbody Rbody in RagdollRigidbodies)
        {
            Rbody.isKinematic = false;
        }
    }

    public static Rigidbody[] RagdollRigidbodies;
    public static void RagDollOff()
    {
        GetRigidbodies();
        foreach (Rigidbody Rbody in RagdollRigidbodies)
        {
            Rbody.isKinematic = true;
        }
    }

    public static void GetRigidbodies()
    {
        RagdollRigidbodies = Clown.GetComponentsInChildren<Rigidbody>();
    }

    public static void ChangeTags()
    {
        foreach (Rigidbody Rbody in RagdollRigidbodies)
        {
            Rbody.transform.tag = "Target";
        }
    }
}```

[timid dove]

eh... Seems like it would always be 170 to me... but what object is this script attached to?

[stuck bay]

the head of the ragdoll

[timid dove]

Oh wait also - why is Player and Clown static

I see the problem

[stuck bay]

to spawn them from other script

[timid dove]

you have one of these scripts on each clown

and since Player and Clown are static - every copy of the script is running Update at the same time

so they are all adding forces to the same clown

[stuck bay]

ok yes

[timid dove]

in a nutshell - don't use static variables. You don't need them to access things from other scripts

[stuck bay]

how do i spawn them then?

[timid dove]

To spawn a prefab? Just create a serialized variable:

public HumanLauncher myPrefab;

assign that to your prefab in the inspector

and instantiate it:

HumanLauncher instance = Instantiate(myPrefab);```

then you can do anything you want with instance

[stuck bay]

cool , thanks

[wary ferry]

is it ok to do RigidBody2D.AddForce within Update? I know FixedUpdate should be used for physics, but I am using Input.GetKey for movement right now and that is making it overly complicated (have to have a bool to check if the key was just pressed for each type of movement, would be easier to use Input.GetKeyDown instead but sometimes it isn't called when I put it in FixedUpdate).
Is that ok to do? I would also be calling Raycasts in there

I can't think of a reason that this could be a problem, but Ive been told FixedUpdate is the place to put physics calculations

[shell adder]

really u should be doing all physics (including raycasts) in fixed update as it is more consistent than update and so will produce more reliable results across the board, and ur right with putting input in update as sometimes fixed update can miss inputs, but it is definitely worth it (at least for me ) to have the 'complication' of setting a bool to true than false in order to have both reliable input and reliable physics

[limpid hornet]

Idk if this is a physics thing or what the actual cause it, but I need to figure out why this is happening. This is made from two models arranged like tiles on a grid. The each have a mesh collider. According to Blender the models edges are identical -- I checked the position of each vertex and they all coincide with the vertex on the other model. Yet my ball doesn't roll smoothly across the seam.

[shadow seal]

@limpid hornetI think you should manually place box colliders in the place of all of the mesh colliders

unless this is procgenned

then I think there's a problem

[shell adder]

oh a scam

how do u get the mods

alright gone now

[stuck bay]

you can use probuilder to make them a single object that will solve it

[devout token]

There are some solutions to this that work for some but not for others
-Combine them into one solid collider
-Make sure your floor collider is a simple plane so it doesn't have walls that the ball can catch on
-Set the rigidbody to use continuous collision detection or continuous dynamic if your tiles aren't static
-Mess with physics settings like Default Contact Offset or Default Solver Iterations
-Disable gravity on the ball while it's rolling using a tiny ground check

[wary ferry]

Figured out what I was doing wrong, I had my groundcheck like a pixel too low and I guess starting the raycast inside of the ground itself which apparently causes it to ignore the collider it's inside of

[rigid furnace]

Hey all, I'm trying to work out car physics at the moment after seeing a document written by Marco Monster (https://asawicki.info/Mirror/Car Physics for Games/Car Physics for Games.html), and I'm trying to work out how to write this in Unity code:

    Ftraction = u * Engineforce,
    where u is a unit vector in the direction of the car's heading.```

How do I get u in this situation?

[tacit laurel]

I thought heightmap based terrain collider is way faster than concave mesh collider!! on switch it's super slow at least with these settings. Anyone knows more about terrain collider?

[tacit laurel]

31K active contraintswith terrain collider

[tacit laurel]

90k with concave mesh collider

yet the concave mesh collider is much more performant

[young nest]

How bad are mesh colliders? Like, I want to be able to shoot through fences nicely in an Oculus Quest game. Is that ok to just use the Mesh Collider, do you think, or will I have to make a bunch of box colliders?

[rigid furnace]

That would depend on the amount of vertices you have on those fences

Can you send a screenshot of the fence that you have right now?

It really depends on the kind of fences you're working with

[rigid furnace]

In this case you're better off using a bunch of narrow box colliders from what I see

[young nest]

I figure the front gate is a no-go and I'll make it destructible, but the side fences might be good to shoot through

[young nest]

ok thx

[rigid furnace]

Although for the top portion you might wanna do something simple

since it kinda curves you can either:

[young nest]

Yeah I'll use box colliders for the top

Oh, the curves I won't care about

[rigid furnace]

oh good

[young nest]

No one will be up there

I think....

So pretty much NEVER use Mesh Colliders unless they're super simple convex shapes, yeah?

[rigid furnace]

Ahhh

Nah

It's more like

mesh colliders is more or less used for if you want to have more detail

for the collision for the object

However for a system like the Quest

you wouldn't want to make that kind of sacrifice to performance

because mesh colliders use more vertices

[limpid hornet]

Do you have a good guide for this? I don't know much about ProBuilder. I've managed to get the individual meshed combined into a single ProBuilder mesh, but I want to get a Mesh to use in a MeshCollider and it keeps throwing errors when I call GetVertices();

[stuck bay]

public GameObject gameImpact;

GameObject GameO = Instantiate(gameImpact, hit.point, Quaternion.LookRotation(hit.normal))

[stuck breach]

Hello . Am I can use Character Controller with Rigidbody?

[wide nebula]

They're not meant to work together, no.

[thin solstice]

@young nest quick question. did you make those cars?

Its more #🔀┃art-asset-workflow related but since you posted it here first, id like to know. because those cars are well made

[young nest]

Nope. They're Synty from the Gang Warfare pack

[thin solstice]

Oh alright. thanks for letting me know

[young nest]

That whole scene was the Gang Warfare pack

[thin solstice]

XD

nice

You do physics programming though?

Like physics engines for animations and stuff like that?

[young nest]

Unity does that

[thin solstice]

Not physics engines not really. Not well made.

or generally not really

just a general question cz ive been working on this one physics animation engine and its getting tough so just generally looking for people who might be up to collaberate on it.

Its like ragdoll but you mix it with constraints to get realistic animations

[young nest]

That's cool. I'm not that good.

[thin solstice]

Nah man dont say that. stuff like this are very rare to find being made

[young nest]

I totally understand. You basically want the guy who made Puppet Master

[thin solstice]

puppet master?

[young nest]

It's an active ragdoll and canned animation blender

[thin solstice]

ima look that up but yea active ragdoll is basically the concept

[young nest]

https://www.youtube.com/watch?v=on7wAz0fsGg

[thin solstice]

Yea that.

I made stuff similar, etc... But it gets complex to get all tools done and have that done at the same time. So kinda usually ask if someone is interested in case they had the experience, etc... Nothing special though man its fine. Thanks for the puppet master link though i might take a look at the source code. seems interesting

Ive made some world brush extensions, building generators from modular sets, etc... these type of tools. physics animation is something im not experienced with

[stuck bay]

fyi i solved it using ```c++
this.

[ruby prawn]

can someone help me to simulate the engine of a car on this different situation in unity? i.e. engine running alone or hooked to clutch, and i would like to have the specifications of a real vehicle like this one http://tech-racingcars.wdfiles.com/local--files/toyota-corolla-ae86-gt/AE86GroupA.pdf

I have started to implement this formula https://x-engineer.org/automotive-engineering/internal-combustion-engines/ice-components-systems/mean-effective-pressure-mep/

[young nest]

Anyone here good with PuppetMaster who might be able to tell me why I can't get my guy to fall over no matter how much force I'm adding to him?

I've lowered every possible thing

[timid dove]

https://forum.unity.com/threads/puppetmaster-advanced-character-physics-tool-released.358445/ ask here

[ancient needle]

What would be a good way to get the vertex color of a mesh at a raycast hit?

Looping through all the verts and checking for the shortest distance is sloooow

[timid dove]

RaycastHit has a triangle index and barycentric coordinates for exactly this reason

[stuck bay]

I have a Rigidbody 2D on both my player and my wall tilemap.

And a Tilemap collider 2D and Composite Collider 2D on my wall tilemap.

So it has a collision box like this, but my player can run into it.

[timid dove]

are you moving your player in a physics-friendly way?

[stuck bay]

A really simple way,

using System.Collections.Generic;
using UnityEngine;

public class PlayerMovement : MonoBehaviour
{

    public float moveSpeed = 5f;
    public Rigidbody2D rb;
    Vector2 movement;

    void Update()
    {
        movement.x = Input.GetAxisRaw("Horizontal");
        movement.y = Input.GetAxisRaw("Vertical");
    }

    void FixedUpdate()
    {
        rb.MovePosition(rb.position + movement * moveSpeed * Time.fixedDeltaTime);
    }
}

Is that fine?

[timid dove]

should be

does the player have a Collider2D of any kind?

[stuck bay]

Ohhh that's why.

[timid dove]

yes, both objects need colliders for collisions to happen

[stuck bay]

Ok thank you xD

Should I just use a box collider 2d?

[timid dove]

sure

or capsule

[ancient needle]

Thanks! Guess I need to learn how barycentric coords work then ha

[timid dove]

or whatever you think fits its shape the best

[stuck bay]

Cool.

[timid dove]

The example code here has almost exactly everything you need: https://docs.unity3d.com/ScriptReference/RaycastHit-barycentricCoordinate.html

the only difference is that they're calculating a normal, whereas you want to calculate a color

you should be able to pretty much just replace the normal stuff with color stuff and the code will be 95% the same

[ancient needle]

Wow amazing! Thank you!

[empty rock]

Hello
I would like to know why my projectiles do not reappear with my cubes, however, all these objects have rigid body and collider components
https://gyazo.com/e64888dc382fba5716c602a37b73e5af

there's no reaction between them

[shell adder]

what do u mean by reappear with my cubes?

what's the intended behaviour

[ruby prawn]

How to calculate the inertia of this motor please? http://tech-racingcars.wdfiles.com/local--files/toyota-corolla-ae86-gt/AE86GroupA.pdf
I'm French, I have trouble recognizing the phases, especially since you can't copy and paste the text to translate it ^^.
I would like to calculate the inertia of the engine itself, crankshaft I think or flywheel?

[empty rock]

I mean, something like this
https://gyazo.com/69b38fa93e835909db032cacf4fe6044

[empty rock]

i man react*
sorry

[shell adder]

oh ok

currently when ur bullets collide have u coded for anything to happen

like do they get destroyed

[empty rock]

Yes

but i've disabled that

to see if it changes something but nothing

[shell adder]

i think u'll have to attach a script to the boxes that ontriggerenter they check if they've collided with a bullet and if so u do an addforce equal to the bullets velocity

[empty rock]

i'm using bolt 😅

[shell adder]

oh

i don't know much about bolt sorry

[empty rock]

No problem

thanks anyway !

[timid dove]

Do you have Colliders on both objects? Are you moving the projectiles in a physics friendly way?

Are the colliders triggers?

[empty rock]

Yes

[empty rock]

Yes

[timid dove]

Triggers don't interact physically

[empty rock]

Oh ok

[rigid furnace]

Hello, I have a sphere and box collider, and currently the sphere, which is inside the box, is colliding with the box, causing glitches

the desired effect is to have the car model not intersect with any walls

[stuck bay]

So I got a bunch of raycasts in a grid at fixed distance from each other here. The question is, how would you find the corner in this situation?

I would also like to support slopes of 45 degrees so a spherecast from top left to bottom right wouldn't work.

It doesn't help that literally no ledge detection algo on the internet handle this case 😢

[timid dove]

Binary search?
Do a raycast in the middle. If it's still the normal of the "top" section, you know the corner is somewhere in the bottom half, if it's the normal of the "bottom" section, you know the corner is somewhere in the top half. Search the appropriate half. Repeat.

[stuck bay]

I thought about it but this gives me a constant error that is the size of min step.

And it'd be temporally inconsistent.

[timid dove]

what's "min step"

but yes there will be a small (configurable) error

[stuck bay]

So if you rotate the camera a bit to the side, the detected point would end up at a different place.

Well I'd use a fixed step between raycast positions.

Oh, actually...

I guess if I find the 2 points on different sides of the corner I can spherecast at an average angle of both sides.

That'd produce the exact point.

Thank you, I think you gave me an idea.

[young nest]

How does one emulate the force of a strong arrow that rips through an object (body)? Would that be a constant force over several updates until the arrow is through? What if the arrow is not long like a bullet, but a really strong one? I guess I want a huge knockback but I don't want people to fly upwards?

Maybe I'm stoned and even if the bullet rips through it's still just the same as the AddForce()

[timid dove]

AddForceAtPosition with ForceMode.Impulse

one-off

[young nest]

Really? Still impulse?

[timid dove]

why not

[young nest]

Hmm... how 'about "fantasy arrow" that like drags a body and pins it to the wall

Like SUPER strong

[timid dove]

depends on how it behaves then. if it basically ignores the body's mass, i'd make it a kinematic rigidbody and attach the body to it with a FixedJoint

or just start MovePosition-ing the body to go along with the arrow

[young nest]

Hmm.... you gave me an idea... attach and Coroutine to addforce continuously for X time depending on .... I don't know how to calculate model depth

I shouldn't care, I'll constant that

If I addforce over a few FixedUpdates that should look ok, right?

[timid dove]

I don't really know because I don't think I have a good mental image of the effect you're going for

[young nest]

I will definitely have to figure out what to scale the addforceatposition to giving t, probably just /72 or 120?

[timid dove]

why use magic numbers

[young nest]

Kinda like imagining a legolas level arrow that hits an orc and nails it to the wall

Cuz 72 frames or 90hz or something

[timid dove]

but that's not constant across devices etc

[young nest]

Refresh of the Quest

Sorry, I'm really high, lol. I mean, I'm writing for the Oculus Quest

[timid dove]

refresh rate isn't really relevant here, it's the physics simulation rate that matters

this is what Time.fixedDeltaTime is for - but AddForce by default already multiplies by fixedDeltaTime

if you're in ForceMode.Force

[young nest]

ForceMode.Force!

Thanks!

[timid dove]

that's the default force mode

[young nest]

But is that what is applied in a collision?

I want legolas to shoot an arrow that is so strong it could nail an orc to a wall, but it doesn't because it rips through the orc, and the force throws him back that hard anyway

But it's not an arrow, it's a bullet, so time to penetrate is like 0 because that's the length

I'm sorry, please ignore me, I think I got it.

[timid dove]

If the time is "like 0" just use Impulse.

that's what it's for

[young nest]

You're right. The point is that I wanted emulate that it isn't 0 even though it is, so that's where I got confused. Thank you, you helped me figure that out.

[mighty sluice]

https://i.imgur.com/GSuyP7T.mp4

physics

[shadow seal]

physics

[ember violet]

I am using a golf course asset and was having trouble when the ball would come into contact with the mesh surrounding the hole as. I am not exactly sure how to fix this. I have attached a screenshot showing the mesh and the projected path of the ball. Can someone help me out here? (incase image didn't load: https://imgur.com/a/CFzR464)

[shell adder]

so is the problem that the ball bounces over the hole because of the mesh?

because if so u could resize the mesh so that it doesn't block the hole

[ruby prawn]

How to separate all these forces in unity? and how to make a numerical integration with please for a week I can not make something correct https://x-engineer.org/automotive-engineering/chassis/vehicle-dynamics/calculate-wheel-torque-engine/

[dark roost]

why are my rigidbody2d falling so slow? all of the values are default

[shell adder]

rigidbodies have a mass value u can increase that if they're too slow

[dark roost]

okay

[feral mango]

If i want to create custom ball physics, what collision detection system should i use? In my head i can imagine only CircleCast approach.

[hushed fractal]

i got 2 game objects children of another one. Each on has a rigid body and they are connected with a configurable joint. The break and torque force are set to infinity but it doesnt work. When i grab one the other one doesnt follow

[devout token]

Usually CircleCast is used for lines with a radial thickness, as it's not just a circle

[feral mango]

So what can you recommend ?

[devout token]

That really depends on what you want out of your custom physics
And more importantly why would you try making your own system instead of using the existing one

[feral mango]

I am not looking for easy ways 🙂

[devout token]

What problem are you trying to solve, I mean

[feral mango]

Create custom ball physics. For now it is just a challenge

[devout token]

Ah
Good luck then

[valid furnace]

I have a ray cast that doesn't detect objects ...

i don't understand why it doesn't detect other objects

can anyone help me ?

[frigid pier]

@valid furnace Raycast uses it's layermask. Make sure you set it up correctly. You can also inverse it to test with ~

[valid furnace]

inverting it worked well, don't know why, thank you so much

[dreamy sun]

How can i make the rigidbody of my player travel into walls please?

please?

[brazen echo]

Hi all. Slamming my head against a wall for this one for a while.

I've been googling for 3 days about this, but I encountered an odd bug including an inconsistency between Editor and Build versions. From what I've boiled it all the way down to, it's an issue with RaycastHit.textureCoord not calculating properly in the build, but working fine in editor. Some of the comments I've found were about convex mesh colliders not working, which I'm not using (I'm using regular mesh colliders). Another rather condescending person said "so you're trying to use mesh information without actually having it in your build?" which I was unsure how to parse.

My question is, does anyone have any additional information on how to guarantee that my textureCoord reference will be accurate in the build version? I've tried just about everything I could think of so far.
If you're unsure what I mean, here's an example in editor. I effectively have two cameras, two meshes, and two textures getting output from the cameras so I can "mirror" what's happening in a different part of the scene. It works perfectly in editor, and that green crosshair gives me an accurate position through the mirror. However, in build, it defaults to the farthest left corner point which I assume is 0,0.

[brazen echo]

You can set your walls to a specific layer and your player to another, then go into Project Settings > Physics and uncheck collision between the two.

[mighty sluice]

@brazen echo could be some kind of lag or race driven problem; your build environment might not work exactly the same as the editor. For example, if physics is involved, it's possible that could contribute to deviations

You should try simplifying your raycast (making it more thread safe is possible) and see if that solves anything in build versions

[brazen echo]

It's odd because the raycast itself seems to work, it's just that the textureCoord it's returning is incorrect

All of the other different RayCast methods I'm using in my grab/interact logic seem to work fine, and of course, this method also works in editor and not in build for some reason

Someone online suggested it might have something to do with the build not getting the same information about the UVs on the mesh during runtime

On a thread I stumbled upon

[dreamy sun]

OK THANKS

[delicate vigil]

Hey all, i've been working with 2d Colliders and cant seem to configure them right. my player object just drives right through the obstacles. when it does the player sprite just spins wildly. also i can drive sraight off the map. how can I fix this?

[brazen echo]

@mighty sluice could it have something to do with the MeshFilter's UVs?

Well, no probably not huh. Since it works in editor.

[mighty sluice]

possibly but i would not guess that. if not a threading issue i would suspect that physics is moving the actual mesh differently

anything that could alter where the raycast lands on the mesh...

but it could very easily be something with the UV's

what is your build target?

[brazen echo]

I'm switching up UVs and testing

Sorry, can you elaborate what you mean on build target?

[mighty sluice]

the platform

android, mac, windows?

[brazen echo]

Vector3 p = hit.textureCoord; Camera c = hit.transform.parent.GetComponent<ReverseRef>().cam; Ray r = c.ViewportPointToRay(p);

The problem is only in the build. This is the point at which is stops working in build.

Windows.

Basically the mirrors both have cameras on them. I have insured there is no raycasting issue (since it works in editor) regarding collision or raycast layers. I take a reference point from the first camera to the point it hits on the "real world" mirror and cast using that reference point from the mirror camera which is static. Seems to work perfectly when I run it. Only messes up when I export.

[mighty sluice]

yea i got no ideas...

I would post this in #archived-code-general instead of physics

doesn't seem to be a physics issue really, and someone with an idea is more likely to see it in general

[brazen echo]

kk. I'll give it a go.

[delicate vigil]

hey guy's do i have to add code to my movement script in order to make colliders work correctly? my player sprite just keeps driving through everything on my map. I've tried kinematic and static but those dont work either. both my player sprite and tree sprite have ridgidbody2d and box colliders.

[static plover]

https://help.vertx.xyz/?page=Programming/Physics Messages try this

[crystal zodiac]

Wheels and colliders move car doesn't

What did I do wrong

Can anyone help me

[vast meadow]

why might this be so stuttery

oh well when the video is laggy you cant see but

    void FixedUpdate()
    {
        if (Input.GetMouseButton(0) && heldObj != null)
        {
            int layerMask = 1 << 3;
            layerMask = ~layerMask;
            RaycastHit hit;
            if (Physics.Raycast(cam.transform.position, cam.transform.forward, out hit, 5f, layerMask))
            {
                heldPoint.transform.position = hit.point;
            }
            else
            {
                heldPoint.transform.position = Camera.main.transform.position + Camera.main.transform.forward * 5f;
            }
            Rigidbody rb = heldObj.GetComponent<Rigidbody>();
            rb.velocity = Vector3.SmoothDamp(rb.velocity, ((heldPoint.transform.position - heldObj.transform.position) * 1600f * Time.smoothDeltaTime), ref smoothHoldV, Time.smoothDeltaTime);
        }
    }```

[vast meadow]

nvm it was smooth it was just the rotation not changing

[obtuse pond]

I have a method that can make a raycast on a untransformed Mesh

is there a way to apply a LocalToWorld matrix to the raycast so that it is equivalent to applying the same matrix to the mesh?

[viral ginkgo]

@obtuse pond matrix * vector, thats how you apply a matrix transform to vector 😄

[olive musk]

when implementing physics-based knockback on kinematic navmesh agents, does this general approach work?

1. disable navmeshagent and kinematic setting on rigidbody
2. apply force to the rigidbody
3. wait for it to stop moving
4. re-enable navmeshagent/kinematic

[jade ocean]

Hey, how can I implement the spring force equation(F = -kx - bv) to a rigidbody object hanging from a target point due to gravity

[timid dove]

You've got the formula right there, right? What part are you struggling with?

[jade ocean]

I don't know how to use the formula in code ._.

[timid dove]

In FixedUpdate:

Get or calculate all the values on the right side of the equation. Do the appropriate arithmetic and calculate your force. Then apply that force to the Rigidbody with AddForce

[jade ocean]

Can I do this without AddForce?

[timid dove]

Why?

You have a rigidbody... you're calculating a force you want to apply to it, and you don't want to use the primary and most straightforward way of applying forces to it? 🤔

[jade ocean]

I want to know how to do add a force to the acceleration of an object explicitly

[timid dove]

what does that mean?

The effect of adding force is to change the velocity of the object
A change in the velocity of the object is, by definition, acceleration

that's what acceleration means

[jade ocean]

Yes, sorry

[timid dove]

and that's the only affect adding force has

[jade ocean]

So would I add the force to the current velocity in FixedUpdate?

What about mass?

[timid dove]

you add force to the Rigidbody. This has the effect of modifying the velocity

[jade ocean]

I forgot physics 😫

[timid dove]

The more massive your object is, the less acceleration will result from the force

Unity will account for the mass automatically when you call AddForce

[jade ocean]

But what if it was not a rigidbody

[timid dove]

Then you have to do all the calculation yourself

The relevant equation is F = ma

force = mass * acceleration

that means the acceleration that results in a force equals Force / mass

a = F / m

[jade ocean]

Right, forgot and I though it was a = fm

[lunar magnet]

why is my configurable joint causing my object to rotate slowly despite setting its maxangular velocity to be high? im trying to make a car using configurable joints but the wheels are rotating slowly when going down a ramp and i dont know why

[frigid pier]

Are you using wheel colliders?

[lunar magnet]

no im using cylinders with mesh colliders and attaching them to the car body using configurable joints

i have bad experiences with wheel colliders

[timid dove]

Well for one there's a physics-engine-wide maximum rotational velocity.

That might be part of the problem

[lunar magnet]

i know and i set the max angular velocity to infinity

i made this script

[frigid pier]

Also friction, not enough mass... Also physics engine is not quite exact with collisions. There's a reason wheel colliders exist. They wave some things off to work properly.

Also check resistance on the joint, it has a lot of settings to consider.

[lunar magnet]

wdym resistance

[frigid pier]

Damper force https://docs.unity3d.com/Manual/class-ConfigurableJoint.html

[dreamy sun]

how to make a rigidbody dont travel through walls?

[frigid pier]

@dreamy sun Use physics methods to drive physics objects using FixedUpdate. You can find tutorials on it in Unity Learn.

[dreamy sun]

Can you send the link please?

[frigid pier]

@dreamy sun Links are pinned in #💻┃unity-talk and in #💻┃code-beginner

[dreamy sun]

Ok thanks

[waxen nova]

Can someone help me pls. I try making a 2D game where my Character shoots. I made the Character and the bullet Move with a CharacterController. I try detecting the Collision with void "OnControllerColliderHit" but it isnt working. I tried like very method the Unity Manual/ScriptingAPI has to offer but nothing works. PLS DM if you know a way this thing can work

[timid dove]

CharacterController is a 3D physics component

it won't interact with any 2D colliders

[waxen nova]

can it collide with another character controller

?

[timid dove]

uh...

maybe? If they both have kinematic rigidbodies probably

[waxen nova]

but i cant add a rigidbody to a character controller

[timid dove]

sure you can

Add Component -> Rigidbody

set Is Kinematic to true

[waxen nova]

than i get a null reference error

[timid dove]

?

where

[waxen nova]

wait

[copper olive]

I want my enemy to kinda float in air and follow my player

Is there anything extra I need to do for that?

Or is it the same as on ground?

[stuck bay]

Help

[timid dove]

just offset the enemy's renderer(just the renderer, nothing else. Move it to a child object if needed) by as much as you want on the y axis

[olive musk]

i'm seeing different behavior when adding force to a rigidbody at rest, as well as to a different rigidbody which starts as kinematic but sets isKinematic = false in response to a trigger before the force is applied. the body which disables kinematic on-demand appears to be reacting much stronger to the force being applied. is there an explanation for this?

[timid dove]

friction maybe?

the dynamic body is pushing against the ground and has some inherent downwards velocity causing friction, but the kinematic body has no such downward velocity at the start and therefore no or less friction with the ground?

[olive musk]

is the friction accessible via fields which i could inspect/log?

[timid dove]

it's part of the PhysicMaterial(s) involved

[olive musk]

basically i'm just trying to understand whether the behavior i'm seeing is expected (and then tune the force being applied to plan for it)

[timid dove]

and if you're not using custom PhysicMaterial(s) there is a default material that is used that does have friction

[olive musk]

hm, so i could test by making the non-kinematic body material frictionless and see if it responds similarly?

[timid dove]

so to eliminate this as a possiblility - create a custom physicMaterial that has 0 friction and friction combine set to "Minimum" - and apply that to all of the objects involved (the floor, the objects, etc)

[olive musk]

thanks, i'll try it out. in my initial testing i just waited for a few seconds before applying the force to see whether that changed the behavior, in order to let it "come to rest" but it was the same as without the delay

[timid dove]

you mean you made the kinematic body stop being kinematic, waited a few seconds, then applied the force? And it still went further than the non-kinematic one?

[olive musk]

yes, exactly. the physics debugger shows it changing to a rigidbody and then sleeping. but still gets launched further than the one which began its life non-kinematic.

[timid dove]

Interesting.

• Are the objects otherwise the same? Same mass? Same Collider(s)? Same object(s) they are touching?
• How exactly is the force being applied? Is it a one-time ForceMode.Impulse force, or something else?

[olive musk]

the force a scripted one-time Impulse, correct. objects are just duplicated cubes, one with kinematic enabled.

[timid dove]

dumb question - let's say you just make them both dynamic at the start. Do they still go different distances?

[olive musk]

haha, no dumb questions i appreciate the sanity check. they behave identically when they start with the same kinematic option at the start. i also have played with setting a frictionless physic material on the non-kinematic body, and it goes the same (shorter) distance after impulse, but now slides when it lands. :]

[timid dove]

what about if you wait a second and make sure the non-kinematic body falls asleep before applying force to it

maybe it's related to sleep? 🤔

[olive musk]

i'm using the same logic for both impulses, so i've seen that the behavior between the kinematic types is the same either with or without the delay

at least it seems i've confirmed this behavior seems odd, heh

i'm using 2021.1 if that is relevant

[timid dove]

what's the code for this look like

[olive musk]

Rigidbody rigidbody = go.GetComponent<Rigidbody>();
rigidbody.isKinematic = false;
rigidbody.AddForce(direction * pushForce, ForceMode.Impulse);```

pushForce is set manually to 10

this is happening in a coroutine, and i've played with WaitForFixedUpdate to see if that changes anything, but no results

[timid dove]

is direction being normalized?

[olive musk]

yeah it's normalized. if i swap the kinematic setting on the cubes, they swap behavior even though the angles are slightly different.

for completeness, csharp Vector3 direction = (other.transform.position - transform.position).normalized; Vector3 right = Quaternion.AngleAxis(90, Vector3.up) * direction; Vector3 pushDir = Quaternion.AngleAxis(-45, right) * direction; StartCoroutine(PushBack(other.gameObject, pushDir));

goal being "push away and up"

[timid dove]

and you're sure the coroutine is running only once per object?

[olive musk]

good question, the sphere is a trigger collider and i'm using OnTriggerEnter. let me confirm with some debug logging.

i think you got it. looks like the kinematic cube activates the trigger again when it changes to non-kinematic.

[timid dove]

ah!

The physics engine is full of weird little edge cases like that

[olive musk]

thanks for walking me through it :]

[timid dove]

"what happens when a collider is disabled inside another collider? What happens when it's destroyed? What happns if you change its body type? What happens if you change the collider from a trigger to a non-trigger" etc..

lots of weird interactions there

[olive musk]

haha yeah i'm sure i have lots of discoveries to make as i learn 😛 and with a bit of bookkeeping to prevent duplicate triggers, things are moving as expected now. thanks again.

[timid dove]

don't use a second rigidbody

just a second collider as a child object, on a separate layer

make that separate layer only collide with itself

Just for neatness I would do like:

Sphere (Rigidbody, whatever else)
- main collider (SphereCollider, layer = default)
- special collider (SphereCollider, layer = spheresonly)

And in your physics settings just set the spheresonly layer to collide only with itself

stupid name but yeah

yeah that turns the child into a completely separate, independent physics entity

[vast meadow]

ontriggerstay is firing for the object to the right even though the only triggers are where the arrows are pointing

heres the objects trigger box

absolutely lost

for some reason its detecting on trigger stay from the mesh collider thats not a trigger??

[lunar magnet]

how do i undo the effects of physics.ignorecollision?

[lunar magnet]

nvm i figured it out

[vast mulch]

hey, Im working on a space game where the player explores planets and moons. But im finding an issue where if I rotate a planet the player's position doesn't follow the floor of the planet relative to the original position of the player on the planet. I tried making the player a child of the planet but it bugs out the player movement, does anyone know how I could fix this?

[ember violet]

How can I edit meshes?

[shell adder]

u use a program like blender to edit the mesh and if u've attached a mesh collider then that should resize it

[shell adder]

or you could use other colliders like box colliders instead

[ember violet]

I can try this

Thanks

[tacit hearth]

OnTriggerEnter2D being called every update. How can i fix it. I only want it to call once.

[ruby prawn]

how to simulate the speed of an engine in relation to its performance?

[vast mulch]

anyone? lol

[timber holly]

Hi everyone, I am doing a minigolf game and have a problem with physics here. The issue is when the ball rolls over a transition/edge between two colliders (from two cubes making the ground). The ball will jump cause that transition/edge.
I found the same issue from a reddit user: https://www.reddit.com/r/Unity3D/comments/5m34o7/3d_rigidbody_colliding_with_the_edge_between_two/

Has anyone been through the same issue? Any help is appreciated.

[thin hamlet]

I'm working on a 3D fps-ish game where movement is pretty important, I decided to go with a character controller which I think should be better in this situations (tell me if I'm wrong), I'm really satistied with overall character controller functionality, yet the problem is that I'm really missing .addForce() feature from Rigidbody, I tried to figure out some solutions, I also tried googling for some, yet everything I created / found just didn't feel like add force should feel. Does anybody know how to correctly integrate add force function into character controller or do you think I should just switch to rigidbody?

[timid dove]

The problem is that you would need to simulate momentum

basically you keep a current velocity vector around, and only manipulate that velocity vector additively

never overwrite it completely

then you can do things like add a bunch of velocity in a certain direction to simulate a knockback or impulse of some kind

this is of course, what Rigidbody is doing internally more or less. it has a mass and velocity and AddForce additively affects the velocity.

[thin hamlet]

Thats basically what I was trying to do right now and It actually turned out to work pretty good

[ornate trail]

Anyone knows a reason for a vehicle turning one side with way more grip than the other?( using wheelcolliders btw)

[karmic ravine]

Dose it possible to not bounce on step object like slider? If I go fast

[lapis plaza]

@timber holly I didn't read the reddit but basically what you are seeing here is coming from physics engine feature called "contact offset". First thing to try is to set that to as tiny value as possible, then try to minimize the collision edges by overlapping them a bit (this only helps if the collision edges are not in 100% same angle)

if you are willing to do extra work for this and can use new enough Unity version that supports contact modifications then you could see this forum post first:
https://forum.unity.com/threads/experimental-contacts-modification-api.924809/#post-6482950 and after that read what I wrote on the topic here regarding the rolling ball case: https://forum.unity.com/threads/experimental-contacts-modification-api.924809/page-2#post-6720985

You do need 2021.2 version for this to work, so I'd pick the newest beta from hub if you want to test this

[vapid tusk]

Is it possible for a game object, with a collider, to know when a raycast hits it, other than with the raycasting object sending it a message? I.e. for the game object that is hit by the ray, to respond like it was hit with a collider?

[shell adder]

no i don't think so

u'd have to get the gameobject from the hit and get the script component and call a function from that script

[vapid tusk]

@shell adder Thanks. That is what I was going to do. I just thought it would be easier, if it could be treated like another collider hitting it.

[shell adder]

if u want it to know that it was being hit then instead of a ray u could use a thin box collider and have it be a trigger

[vapid tusk]

@shell adder That's an interesting idea. I'm not sure if I can make it work, because it's coming from the Player, which is moving around, however, I'm going to think about this idea some more. Thank you!

[shell adder]

alright

[timber holly]

Thank you very much, just changing the contact offset to a lower value did the trick. Thank you! 😁

[lapis plaza]

@timber holly as a side note, I think you can change the contact offset from collider or rigidbody, but physics settings has a global setting too

[heavy basin]

Hi there ! Currently im working on a highly physics based 3D game. The game consists objects colliding with each other at high speeds and other things that have a lot to do with physics. My main question is : How scales of 3D objects should be like to have the best performance, stability and realism in highly physics based game ? For example, is realistically sized football ball okay for the best performance and stability? My second question is : How scales of 3d objects should be in general to have the best performance ?

[ruby prawn]

How to apply the final force of this scheme on the wheel collider?

[spiral tulip]

someone correct me if i'm wrong but i don't believe the scale of objects affects the overall performance, as long as the number of vertices and triangles in the mesh stay constant

[dreamy pollen]

Anyone know off-hand if freezing locally unmoving rigidbodies improves performance? (mine are kinematic and are being moved with a parent animator)

it's a micro-optimization, if at all, I'm sure

[frigid pier]

@stuck bay https://docs.unity3d.com/ScriptReference/CollisionDetectionMode.Continuous.html

[stuck bay]

yeah i looked into that, it seems to have solved the issue

thank you

[stuck bay]

my best guess is that this is also a physics thing... i have a relatively simple script attached to 16 balls (https://pastebin.com/DS2btZtd) and when i press R, they all teleport into this arrangement - but only once, and then it works after. i have no idea what could be happening with this

[stuck bay]

this occurs both in the build and the standalone player, i'm using fixedupdate for the physics, the player controlled ball has continuousdynamic and the other balls have continuous collision

i have to go for a while so if anybody knows what this could be pls ping me

[vast meadow]

bruhh why are unity physics so bad

why is this walking??

theyre joined by fixedjoints and have no collision between them

[vast meadow]

so the fixed joints are forcing an empty rigidbody parent away from it for some reason

underneath the plane

[desert timber]

Can anyone give me a hint on how the CharacterController is detecting the ground slope? I'm writing a player controller using the CharacterController, and am wondering why we need to detect ground slope ourselves (I see tons of great tutorials for the task) if this module is already calculating ground slope?

[heavy basin]

Thanks for the answer

[stuck bay]

When I move my First Person controller based on a rigid body, the camera moves a tiny bit downward when I move on the ground.

If I set Interpolate, the rigidbody keeps bouncing a tiny bit up and down while moving.

[desert timber]

this is weird right? that we have a CharacterController that calculates ground slope via complex a method then doesn't expose it to us?

I'm reading that it's a Physx implementation

the original exposes slope and other properties

[stuck bay]

When I used the character controller it had issues with colliding with moving colliders

Notably when moving backward into them

[fierce thistle]

Do we have any way to do a shapecast with a mesh?

[shrewd ibex]

Guys, do the skin width of the character controller makes the player not able to interact with triggers? Or does it works the same as a collision for the trigger?
because in my game when I put a bigger skin width my character has problems detecting a trigger that is in front of him

[desert timber]

Yes, skin width is a sort of buffer around your character that will not collide/trigger anything. But, that would be some thick skin! 0.02 isn't very big so maybe something else is happening?

[shrewd ibex]

Okay, thanks! I’ll give it a look to see what do I find

[last stump]

Does OnTriggerEnter2D only work if one of the colliding objects has isTrigger to true?

[static plover]

Yes, otherwise use OnCollisionEnter2D

[left rover]

Hey, guys, I am trying to fix this issue where I have a time trial game, and you can control a vehicle (car, plane or boat). I set the centerOfMass for the Rigidbody for the car, but as soon as the car lands on the road, it topples over. The car should not topple over. I am doing the Junior Programmer course in Unity, and I was wondering if someone can help.

https://github.com/bhlee90/Programming-Theory-Repo

[desert timber]

I think you're sending incorrect arguments to transform.Rotate, double check that maybe

[stuck bay]

Hey guys ,
I have a list of 4 food items
I want if they collide with each other
position of any one of them changes
any idea how can I do so ?

[gilded sparrow]

Hi all
Just a simple question: Mesh collider of a quad faster than Box collider?
Use case: For borders (have no rotation therefore aligns to AABB nicely) and prop/stage shapes

I searched and still pretty vague

Quad mesh collider set to convex, turns it into a cube.. is THIS faster than Box colliders?
Or.. since it turns it into a box, is it just telling me to "just use a box, man.." ?

[timid dove]

I would guess a box collider is faster than any mesh collider

the algorithm is a lot simpler

[lilac patrol]

Hey, I'm having a weird issue with rigidbody physics. In my game you can shoot a bow & arrow (rigidbody arrows), and the physics for that works fine (mostly). It's a very simple system; when the arrow collides with something, it freezes in place. The problem is that if I'm very close to what I'm shooting at, the arrow will bounce off and fly far away. I have no idea what could be causing this.

[stuck bay]

Hi, I got an issue I don't know how to fix:
I have 3 cubes next to each other with perfect spacing (no gaps) all cubes are 1 by 1 by 1 and have a box collider. it looks like this: https://i.imgur.com/EvPnCRt.png
On top is a ball I can move with WASD using the rigidbody.AddForce method. When the ball rolls over the edge of a cube it jumps a bit as if it would go over a bump.
I don't know why as the cubes are all at the same height and have no rotation. Shouldn't the ball just roll over it as if it would be a flat surface?

[stuck bay]

pls

anyone help

[shell adder]

sometimes that can happen when u've got two different colliders, if ur worried about it then consider using one long box collider or a composite collider and that should smooth it out

[dreamy sun]

please where can i find a tutorial for stop my player going through walls pls?

[wide nebula]

YouTube

[stuck bay]

Add torque my friend

Experiment and i highly recommend you to check out unity manual Addforce, Addtorque,Addforceatpos section

[stuck bay]

Make sure u have collider attached to walls and also player-wall box checked

in physics section but you did not give full details so i foresee this will not be that useful but hope helps

[dreamy sun]

already done x)

[dreamy sun]

ok i try the solution from a website and i chexk

check

[stuck bay]

Oh k glad u solved ur problem tho

ugh

[dreamy sun]

no wait i WILL try

i wait that it compile the scripts

[stuck bay]

if u want help feel free to dm me

[dreamy sun]

ok thanks :)

[left rover]

Nah, even though I comment out the transform.Rotate line, I still have the same problem

[timber holly]

I had actually changed the value from the physics global settings, because I didn't found it in the collider nor the rigidbody component 😂

[lapis plaza]

did you find it now? 🙂

[young nest]

I've tried a few different things and still can't get this ragdoll problem to work. I'm trying to replicate this "ragdoll flies a bit with arrow" effect

But all I'm getting is this tumbling over effect because it's just... getting dragged down. I'm using Puppetmaster just like the dev in the first example.

[last stump]

Let's suppose I am throwing an object/ball in the air and, at some point, the ball starts falling (obviously). How do I check whether the ball is in the falling phase? Is it as simple as checking its rigidbody velocity?

[timid dove]

check if the y component of velocity is negative, yes

technically it's "falling" the whole time

[shut timber]

Guys, as we know, game like shadow fight 2 and vector use 3d mesh. But does those game use 2d collider or 3d collider ?

[timid dove]

I would guess 2D but who knows

it could be either

[shut timber]

Guys, I'm trying to give damage to a ragdoll, but it will get hit multiple times because each bone has its own rigidbody. How do i prevent the child bones from sending collision message ?

[stuck bay]

Physics.IgnoreCollision

[left rover]

Perhaps, there is a bug with https://docs.unity3d.com/ScriptReference/Rigidbody-centerOfMass.html in Unity 2020.3.13f1. When I try setting the centerOfMass in Unity 2020.3.13f1, I get the issue, but if I try it in Unity 2018.4.34f1, I don't.

[timid dove]

what issue?

Sorry I see it now

[dreamy sun]

how can i make a better collider to a high faces object?

[left rover]

My vehicle behaves strangely as soon as it lands on the ground

It topples over for no reason

[dreamy sun]

because it is stop to 256 ;-;

[left rover]

Yeah, I submitted a bug report

[bronze flower]

I don't know what puppetmaster does but it looks to me like you're continuously applying a force to his forehead, so when he starts to tilt backwards that force continues to push him further over and down. Do you maybe need to maybe sure whatever applies the force is only doing it for an appropriately short time?

[last stump]

I want to AddForce in order to shoot a basketball in my game, but its child to another GameObject which also has Rigidbody. Is there a way I can AddForce to the basketball without affecting the parents?

[graceful meadow]

perhaps the basketball could have a kinematic rigidbody, and you set it to dynamic when you want to throw it?

kinematic means that it'll still inherit the position of its parent, and switching to dynamic lets addforce behave as expected

[bronze flower]

Having rigidbodies parented is generally not a super good idea. What's your reason for doing so?

[last stump]

The reasoning was for gravity & movement which ended up not being implemented lol. Thanks for reminding me it was not needed in the end

It's just that when I add a Collider I tend to add an Rb as well most of the time. So I suppose I added it by mistake

Thank you everybody!

[lapis plaza]

@left roverdo note that once someone from Unity replies to that bug report, your email will be visible on that link.. and people can also navigate to all other bug reports you file through that link (you just only have one there)

typically people don't want to share the direct fogbugz links but rather public issue tracker links if Unity does approve the bug report

(it's mainly a privacy concern)

[twilit axle]

Hi,
I am considering buying Game Creator and using their (non-Rigidbody) Unity Character Controller character.
This will save a lot of time and be fun to dive in.
However, I do still want Character to mimic authentic Rigidbody Physics for some mechanics, like certain objects making the Character bounce or swing.
In situations like these, would it work to make a Invisible GameObject with a Rigidbody and child the GC Character to it so that it secretly follows the Rigidbody's position?
Or, what is a good solution so that you don't necessarily have to code physics from scratch in these situations?

[dreamy sun]

Hello, i made a planet model and a script for the gravity toward the planet but when the player goes onto the real top, my player starts turning on himself when i walk

can somebody helps me please?

[left rover]

Oh, Ic. I had no idea. Thanks.

[pliant cairn]

I dont know why player is getting hit by the bullet. I just want the bullet to pass through the player at the moment. The bullet has a rigid body and sphere collider

[desert timber]

I'm not familiar with Game Creator, but it probably works similarly to the Unity CharacterController: that is, the idea of discrete changes in velocity rather than actually keeping track of an exactly simulated acceleration.

The gotcha' with real rigid body simulators is that games simulate in discrete time steps, rather than smooth functions. These steps forward in time "break" reality. One example is that when two bodies/colliders overlap, a push back force is introduced into the simulation in order to separate the two bodies. That extra force is the source of Halo's super leap, and is also found in many many other games.

These are tricky problems to solve, and, for a player character, these glitches will be found.

There's no reason we can't just use velocity approximations and then simulate physics, afaik. But, rigid body simulators are still fun in their own right. As a player, it's fun to find ways to make things get a little out of control!

(although, neither solution solve the problem of avoiding physics :P)

[left rover]

I think you need to check the "Is Trigger" checkbox for the Sphere Collider component

[vocal spade]

when developing a crouching system for a standard FPS type game, is it better to have two capsule colliders at different sizes that you enable/disable between, one at crouch height and one at standing height; OR is it better to just have one capsule collider that you resize?

in theory it should achieve the same effect, except with the resizing you don't have a "jump" in between the sizes that might not match an animation for instance

[forest geode]

Physics.OverlapSphere ( gameObject.transform.position, selectedSkill.range, selectedSkill.layerMask );

Have a question on layerMasks here.
The layermask in question are Layer 10: Character
In the scene im testing, there is a total of 1 gameobject with that layer, and none of his children are.

A bit unsure on how to reference which layermask .. do I say 10, as it is Layer10, or 11 like a normal array/list.
Tried both: Debug on layermask = 10 returns 0:
Debug on layermask = 11 returns 4:

Ive crancked up the range so they should pick up everything in the scene, and i feel at least 1 of those should be "1".

[forest geode]

Solution: selectedSkill.layermask = "1<<10".

[bronze flower]

I would say it doesn't matter. I just always make sure to check that there's enough space for a full-height character before allowing uncrouching.

The really tricky bit is when you're building a zero-G character controller that can face in any direction, that's when it's gets "fun" 😵‍💫

[proper saddle]

Hey everyone. My rigid body is falling really slow and I have no idea why. All the stuff about it is from years ago, many talking about increasing gravity which doesn't seem to be a thing anymore?

[stuck bay]

screenshot the rb

[proper saddle]

Here you go.

[stuck bay]

hmm

i'm guessing you upped the mass to 100 right

[proper saddle]

Yea

[stuck bay]

hmm, it should fall normally. What else is on this object?

[wide nebula]

Mass != weight, upping it won't make it fall faster.

[proper saddle]

It's just a basic sphere. I want it to fall on a destructible object to crush it.

[wide nebula]

How big are your objects?

[proper saddle]

Hmm... the scale is like 29x

[wide nebula]

That's a 30 meter sphere.

If you want "heavier" things to fall faster, you have to apply additional downward force to their rigidbody in their update.

[proper saddle]

Sigh... yea that seems to be working better. 😫

[timid dove]

You know how when godzilla or king kong falls over it takes a really long time?

[proper saddle]

Thanks a lot people

[timid dove]

That's what's happening to your sphere

[wide nebula]

The Rigidbody should have a gravity scale property like the Rigidbody2D one does, but alas.

[timid dove]

The actual speed of falling is normal but the distance traveled looks small relative to the size of the object.

[stuck bay]

can you put a physics material on 3d objects to increase gravity?

[wide nebula]

No

A physics material relates to friction and bounciness.

[timid dove]

Those are for friction/bounciness only

[stuck bay]

ah cool beans

[timid dove]

To add your own custom gravity do this:

void FixedUpdate() {
  rb.AddForce(customGravityVector, ForceMode.Acceleration);
}```

[proper saddle]

Thanks @timid dove

[tawny violet]

Hey all, having some weirdness with a Tilemap Collider and hoping someone could help, been pretty stumped by this trying to debug/find others with similar issues.

I have a tilemap set up with the Tilemap Collider 2D + a static Rigidbody 2D + Composite Collider 2D components for all tiles I want collidable. I have a box collider + Rigidbody 2D set up on my player character.

Everything looks fine when checking the collider lines in the editor as far as I can tell.

But I get some super weird behavior when I test the game - part of the tilemap collider seems to work fine, others seem to not exist, and there seem to be phantom colliders in places.

Any ideas as to why this may be happening? I'm pretty green to Unity and even just tips on how to start debugging this would be helpful.

[last stump]

I want to launch a ball at a random direction at the start of my game using AddForce. How do I randomly generate a direction (what values do I use in Random.Range)?

[timid dove]

Random.onUnitSphere

gives you a vector in a random direction

[last stump]

Alright, and how do I detect if the direction is facing down? Does it have a negative value or something?

Oh wait, it returns a Vector right?

Nevermind, it returns a Vector3 I know what to do lol

[pliant cairn]

Yayy, it works like a charm! 🙂

[stuck bay]

what are some math and physics topics that I need to thorough myself to better understand them in unity AR/VR projects?

[timid dove]

Do you just mean games in general? There's not much special about VR/AR except for the unique camera setup

You'll want to understand Vector arithmetic, Affine transformations and Matrix arithmetic, and trigonometry.

Physics wise you'll want to familiarize yourself with netwonian physics concepts like force, mass, acceleration, torque, inertia, moment of inertia, kinematic equations

[stuck bay]

thanks for the help , ill start with vector arithmetic 🙂

[sick zenith]

How do I prevent my player from going through a composite collider? ; ; I change it's velocity over time in order to get him dashing. But when I do this the character goes through everything. I already set it's Collision Detection to Continuous and got Default Max Depenetration to huge numbers to see if something changed, but this guy still goes through my walls. Thanks to whoever helping!

[timid dove]

how are you moving it

[sick zenith]

I'm changing it's velocity @timid dove

Let me send the script

A second plz

[timid dove]

it should respect colliders then 🤔

[sick zenith]

void FixedUpdate() {
    direction = new Vector2(Input.GetAxisRaw("Horizontal"), Input.GetAxisRaw("Vertical"));
    if (direction.x == 0 && direction.y == 0) {
      direction = new Vector2(1.0f, 0.0f);
    }

    if(!onCooldown & executing) {
      executing = false;
      StartCoroutine(goOnCooldown());
      dashing = true;
    }

    if (dashing) {
      if(dashTimer > 0) {
        dashTimer -= Time.deltaTime;
        character.rb.velocity = direction * dashSpeed;
      } else {
        dashing = false;
        dashTimer = dashDuration;
        character.rb.velocity = Vector2.zero;
      }
    }
  }

[sick zenith]

In case you are interested @timid dove I found this answer

Unity does collision detection at discrete timesteps. So if you have an object that during one physics frame moves more than it's entire size, it can tunnel colliders.

There are three solutions to it:
* Make the collider of the rigidbody a bit larger
* Make the physics time step smaller. What you are optimizing for us making sure that in one physics step you never move more than the entire size of the collider.
* Make sure the rigidbody doesn't exceed a certain speed at which you know, it can't tunnel. You can use drag for this purpose.

[last stump]

I have a bouncy ball. Let's say I want to change its x direction when it collides with something. Can I do it by just Adding Force with -2 * the Ball's current X velocity?

[timid dove]

adding force will acceleratee it in a particular direction. How much it accelerates depends on the magnitude of the force and the mass of the ball

and the ForceMode you use

note that "accelerate" may just mean slowing it down if the force is in the opposite direction of current motion

[last stump]

If I multiply is x velocity by -2, doesn't it accelerate it with double the velocity on the opposite direction?

[timid dove]

no

[last stump]

How can I do it then?

[timid dove]

force doesn't directly translate to velocity

mass and time are part of the equation too

what's your goal?

what do you want the end result to be?

[last stump]

I want the Ball to randomly change its x direction once it collides with the player.

[timid dove]

wdym by "randomly"?

there's only 2 x directions right?

[last stump]

So, for example, if it's bouncing while going left, add the probability of it going right.

[timid dove]

ok but

[last stump]

Um, yes

[timid dove]

with the same speed as before, just in the opposite direction?

or

with a different speed?

or what

[last stump]

Yes, same speed.

[timid dove]

then just take the velocity vector and negate the x component

and assign it back

[last stump]

Won't that affect the way it bounces though? If, for instance, I make it go right instead of left, won't it make it stuck in the right wall (right border of the screen from which it's supposed to bounce)

[timid dove]

why would it get stuck in the wall

I also don't understand how it's a "bounce" if you have a chance of.. continuing in the current direction

[last stump]

It doesn't. It was just a silly assumption of mine.

Its "bounciness" reminds of Head Ball (if you know that mobile game). So it can hit the player's head and bounce up continuing the same direction.

The important part is, what I wanted to achieve worked. Thank you very much again (I might be wrong but I think you've helped me before haven't you? Really appreciate it)

[desert timber]

I'm curious: does anyone have a link to discussion about volume-less colliders? that is, kinds of colliders that can be generated from a MeshCollider tool.

I don't really know much about them, but I'm discovering that they can be annoying to encounter. Eg, the cinemachine's collider looks for a volume, and will clip through if the collider does not have a volume.

I guess this is a pretty vague question, but I'm struggling to get my cinemachine configured well. Also my character has become stuck while playing around with a Mesh Collider applied to weird/unfinished models. I'm wondering if that was a fluke or something to expect more frequently.

[deep field]

this is very beginnner but

how tf https://cdn.discordapp.com/attachments/769107217685151765/867997295575175188/CRUMBLE.mp4

its all rigidbody 2ds how is it doing that

Why is it rotating on the z axis

[warped skiff]

Hey, anyone know what i might be doing wrong? I can't seem to get anything to look like a usable SDF in the tool....

[fast creek]

Hello, I'm trying to use Physics.OverlapCapsule on a custom character controller to detect if the next position of the character is going to be inside of an object, so I can then use Physics.ComputePenetration to figure out the correct position where it doesn't enter the object
This works very well, however, if the object is a terrain with trees it seems to be ignoring the trees, if I try using a rigidbody it does detect the trees and collision works, but I don't want to include a rigidbody on my character controller
Any ideas on why the terrain trees are not detected?

it seems the terrain collider is detected, however, the call to Physics.ComputePenetration doesn't work

[pliant fern]

I've been trying to create 2d softbody physics following this tutorial: https://www.youtube.com/watch?v=3avaX00MhYc but my result ends up looking like the video attached. How do I fix this?

[round scroll]

I have 2 objects, a building with mesh collider and a cube that is seperated into different parts to get destroyed, the cube has Rigidbody, mesh collider and terrain collider, but it just falls trough everything without getting destroyed

[pliant fern]

I think the problem is each bone is rotating on its own when it shouldnt be, but I don't know how to fix it

I think this because when i froze each bone's z rotation it looked a lot more normal

Well not completely normal

[deep field]

Can someone help

[deep field]

bump

[pliant fern]

tried tinkering with it and now it can hang off platforms

which i dont want

and its also very squished now

[pliant fern]

Nevermind, I solved it, and somehow it was that i needed to raise the frequency on the spring joints.

[pliant fern]

It's getting there, but it doesn't quite bounce it enough. What property should I change to get it to bounce it more?

[pliant fern]

I cant seem to get it to bounce more for the life of me

I've looked everywhere and I've found nothing

[dreamy sun]

Hi, i have a problem with my particle system, if i rotate it, the particles dont turn with it it keep like that

[dreamy sun]

Physics material?

[pliant fern]

tried that it did nothing

It needs to bounce other things

[dreamy sun]

but make it more bounce

[pliant cairn]

What are the blue cubes passing though my obstacle? The cubes are rigid bodies(also they have a box collider) and the obstacle has a mesh collider on it.

[viral ginkgo]

@pliant cairn Looks like kinematic movement

I assume you are moving the cubes via transform

Or rb.position or something

You should either handle all movement via force
Or do some raycast checks in your translation code to prevent penetration

[cedar walrus]

freeze rotation on z

[deep field]

how

then my parts wont rotate

[cedar walrus]

if they're being rotated via script they will

[deep field]

supposed to be a ragdoll

[deep field]

no

[pliant fern]

I did that

It didnt do anything

[opaque arch]

Hey guys, I want to put a rolling barrel obstacle in the little 3D platformer game I'm working on, in famous 3D platformer games do they use physics for this type of thing? I searched it on google, but couldn't find a good answer.

[timid dove]

doubt it

if they're moving on a set path with a set speed etc.?

most likely animated.

[opaque arch]

Thank you for your answer, have a nice day!

[strong leaf]

hello, I'm trying to code a 2d platformer and I need the designer to set a predefined jumpheight and initial jumpspeed in inspector. I tried coding it and the player won't reach the exact height, it's something close (8.9 compared to 10)

    {
        if (isGrounded || rb.velocity.y < 0)
            currGravity = gravity;

        if (spacePressed)
        {
            spacePressed = false;

            if (isGrounded)
            {
                //Debug.Log("intra aici");
                currGravity = jumpSpeed * jumpSpeed / (2 * jumpHeight);
                rb.AddForce(jumpSpeed * Vector2.up, ForceMode2D.Impulse);
                //canJump = false;
                canDoubleJump = true;
            }
            else if (canDoubleJump)
            {
                //gravity = jumpSpeed * jumpSpeed / (2 * jumpHeight);
                rb.AddForce(jumpSpeed * Vector2.up, ForceMode2D.Impulse);
                canDoubleJump = false;
            }
        }

        rb.AddForce(currGravity * Vector2.down, ForceMode2D.Force);
        rb.velocity = new Vector2(hInput * speed, rb.velocity.y);

        Debug.Log(rb.position);

    }```

this is the code I've written so far

basically right before jumping I'm setting gravity as v^2/(2*h) and resetting it when the player reaches ground or is falling

[timid dove]

what's the mass of your object

[strong leaf]

1

and drag is 0

[timid dove]

ok that doesn't matter then, but generally would would multiply the gravity force by the object's mass, which is how you get the effect of all objects falling at the same speed as in real life

but since it's 1, it's moot

you have the normal gravity scale set to 0?

[strong leaf]

yes

[timid dove]

so I mean there is the whole idea that... even with perfect setup, since Unity's physics are simulated discretely, the formulas may actually be slightly different. Because you don't have smooth acceleration from gravity, you have it coming in chunks on the fixed updates

so instead of a parabolic curve you end up with sort of a parabola-shaped thing that has straight lines and corners

[strong leaf]

so you mean changing the fixed update step would make it more precise right? is there any other way to make jumpheight more precise?

[timid dove]

yeah making fixed update smaller would reduce the error from that

[strong leaf]

strange, I tried making it smaller and the max height gets crazy, it reaches 40

[timid dove]

can you show your Update()?

[strong leaf]

    private void HandleInput()
    {
        hInput = Input.GetAxisRaw("Horizontal");
        if (Input.GetKeyDown(KeyCode.Space))
            spacePressed = true;

    }

    //Flip player when changing direction
    private void ChangeDirection()
    {
        if (hInput > 0.01f)
        {
            if (direction == Direction.left)
            {
                transform.localScale = new Vector3(-transform.localScale.x, transform.localScale.y, transform.localScale.z);
                direction = Direction.right;
            }

        }
        else if (hInput < -0.01f)
        {
            if (direction == Direction.right)
            {
                transform.localScale = new Vector3(-transform.localScale.x, transform.localScale.y, transform.localScale.z);
                direction = Direction.left;
            }
        }
    }

    private void Update()
    {
        HandleInput();
        ChangeDirection();

    }```

[timid dove]

hmm looks fine

[strong leaf]

strange

[pliant fern]

It still doesnt really want to make things bounce more

[stuck bay]

Okay this is a wild one

transform.localRotation *= Quaternion.AngleAxis(parentBody.velocity.magnitude * turnCrankSpeed * Time.deltaTime, Vector3.right);

So I'm using this to rotate an object, right? Now this implementation obviously performs steps, so something like skipping from say, 3.2 to 3.5 and so on

I need something to have a smooth interpolation

And as a requirement, it needs to be in Update()

So basically instead of 3.2 -> 3.5, I want it to go, say, for the sake of sanity, 3.2001 -> 3.2002 -> 3.2003 and so on till 3.5000

But, I need it to be as fast as it otherwise would be

[timid dove]

pretty standard interpolation stuff.

Set a target

interpolate to it over time

Quaternion targetRotation;
...
targetRotation = transform.localRotation * Quaternion.AngleAxis(parentBody.velocity.magnitude * turnCrankSpeed * Time.deltaTime, Vector3.right);```

then in Update:

transform.localRotation = Quaternion.RotateTowards(transform.localRotation, targetRotation, Time.deltaTime * degreesPerSecond);```

[stuck bay]

Thanks a ton!

Okay um

[stuck bay]

Where do I put this?

[timid dove]

calculate the target... whenever the target would change

if that's every frame then it goes in Update

[stuck bay]

Okay, I'll check again then

[timid dove]

and then maybe it becomes something like

targetRotation = targetRotation * Quaternion.AngleAxis(parentBody.velocity.magnitude * turnCrankSpeed * Time.deltaTime, Vector3.right);```

that might make more sense anyway actually 🤔

[stuck bay]

Right, missed that

[timid dove]

Quaternion targetRotation = Quaternion.identity; to initialize it

[stuck bay]

Yeah, basically it's a wheel that the player moves with 😅

Gotcha, thanks!

Okay, that works as expected, but not the uh, use case I'm using it for

 vDistance = Vector3.Distance(transform.position + Vector3.up * spokeLength * -1, transform.position + (transform.TransformDirection(wheelSpokes[activeSpoke].spokeDirection) * spokeLength));
        vRatio = Mathf.Clamp01(vDistance/1.4f);
        if(vDistance == 0)
        {
            surveyorPassed = true;
        }
        if(vDistance == 0.01)
        {
            if(surveyorPassed)
            {
                if (activeSpoke == 3)
                {
                    activeSpoke = 0;
                }
                else activeSpoke++;
                surveyorPassed = false;
            }
        }
        normalisedFactor = (vRatio - 0.3f) / 0.7f;

        


        aMan.FootAlignment(1- (normalisedFactor), wheelSpokes[activeSpoke].footAlignment.passReach, wheelSpokes[activeSpoke].footAlignment.leftRight);```

This is basically what I'm doing, and hence I wanted the thing to interpolate such that I could extract the exact time vDistance is 0

Though now that I put it this way it kinda seems impossible because it won't be frame consistent, there's always going to be some frame where it's a little more or a little less

[last stump]

If I use <rigidbody>.transform, does it return the Transform component of the GameObject that has the given rigidbody?

[timid dove]

yes

you can do that with any Component

[rich elm]

I have a somewhat collision related question; or moreso what would be the best way to do it. I have a game similar to pic below.

The dark blue blocks are completely non-interact-able and the blue ones are able to be walked on at free, (this is a 3D game, this is just the map as you would see from overhead)

[timid dove]

Is the movement grid-based? Or just the map is a grid

[rich elm]

Would the best way to do collision here, if I was creating the environment in blender and then importing it into unity, be to just have cubes?

The maps a grid but you can free move

https://www.youtube.com/watch?v=e0odTG7f3Zg

It's essentially this

So the environment around and "walls" are decoration, minus like some doors and secret paths, and the light blue is the free walk space.

[timid dove]

cubes are fast as hell, but the optimal collision shapes would probably be to merge the dark blue areas into contiguous convex BoxColliders as much as possible

[rich elm]

So like, one big long box collider?

[timid dove]

For example

[rich elm]

Ah kk ya

[timid dove]

turn that area into those two red and green colliders

if you can keep them as axis-aligned box colliders, they will be super fast

[rich elm]

Another thing for me is I was going to auto-generate a map as the player walks through so they can see their progress (looks similar to the one posted)

IS there any good way to like, "detect"/record a player has moved past another box?

[timid dove]

the math for detecting your current grid coordinate is really simple and fast

so you could just check that every frame (what grid coordinate am i in) and keep track of which the player has visited and not

e.g. no colliders, just pure math

[rich elm]

oho? I feel like I did similar when I was working pre hiatus for me but I truly don't remember

Ahh kk

so if the player is +1 Z or w/e

then they've unlocked that spot

But wouldn't that have issues if you just, lag, and then "bam", now it hasn't checked that spot?

[timid dove]

Something stupid simple like:

Vector3 GridOrigin;
float squareLength;

public Vector2Int GetCurrentCoordinate(Vector3 position) {
    float x = position.x;
    float z = position z;

    int xCoord = Mathf.CeilToInt(x / squareLength);
    int yCoord = Mathf.CeilToInt(z / squareLength);

    return new Vector2Int(xCoord, yCoord);
}```

You mean if you move too fast and skip a spot?

fast moving with low framerate?

[rich elm]

yeah

essentially

[timid dove]

could be sort of an issue yeah, depending on how big the grid is and how fast you plan on the character moving

you could fix it by keeping track of the previous grid position and just filling in all spots between the current and the previous as well

[rich elm]

Hmm, I don't plan for the character to be fast fast, but since enemies kinda pop up in the environment you can expend stamina to dash in a direction quick and avoid em.

[timid dove]

how big is a grid square?

like 1 meter? less?

[rich elm]

Yeah like a meter.

[timid dove]

Do you want them to only "discover" the exact square they're standing on?

Or also all squares in a small radius

[rich elm]

Only the one they stand on, but tbh, I could probably settle with a radius of vision or some deal.

[timid dove]

if there's a discovery radius it's less of a problem

otherwise - i'd keep track of the previous position and also discover squares between previopus and current position when necessary

[rich elm]

Like just do a cast between the prev recorded spot and the new or something, and then unlock all those spaces?

Either way tho. this sounds way more simple than I was anticipating! I dunno why but my brain was saying "if I toss a blender model in and then toss a cube over it it's not going to work", dunno why.

[last stump]

I have a row of Objects simply moving at the same speed (one next to another) on the X axis (same direction) and also moving very slowly upwards. On each screen touch (the project is mobile), I set those Object's velocities as a Vector2(same x velocity, negative velocity with a very big value (for testing purposes)). Regardless of how big the negative velocity gets, the Objects still seem to go up. Any clue why this could be happening? Anything related to the Rigidbody settings?

[timid dove]

if you have other code that's writing the velocity it could just be getting overwritten.

[last stump]

If I have a rigidbody moving downwards and the object with the rigidbody has children with rigidbodies that move sideways, will it make the children stay in their initial y position?

[timid dove]

If the child bodies are not kinematic, they wil be completely independent

if the child bodies are kinematic, they will follow the parent like any other child object

[stuck bay]

Hi! I'm starting on Unity and I have this problem that I can't fix. Terrain have collision and the character still falls through the floor, and clips through all other objects too, even if they have a mesh collider. Idk what to do at this point, at the start of the project it worked fine but suddenly started to just fall

[timid dove]

get rid of the capsule collider on your character

You already have a CharacterController which is a capsule shaped collider itself

extra colliders can mess with the CharacterController

also I hope you're using CharacterController.Move in your script to move the player?

[sharp gale]

I have the following but the character moves very stuttery (character has interpolation enabled on rigidbody):

        private void FixedUpdate()
        {
            Vector3 inputDirection = this.moveAction.action.ReadValue<Vector2>();
            if (inputDirection != Vector3.zero) {
                Vector3 velocity = MakeInputRelativeToCamera(inputDirection) * this.moveSpeed * Time.deltaTime;
                this.rigidbody.MovePosition(this.rigidbody.position + velocity);
            }
        }

However, if I use Update instead it runs very smoothly. I was under the impression that this should be going into FixedUpdate. Any thoughts?

[timid dove]

I don't think it should make a difference as I thought they returned the same thing inside FixedUpdate but what happens if you replace Time.deltaTime; with Time.fixedDeltaTime?

[sharp gale]

Behaves in the same way; and I logged out the value and you are correct; Time.deltaTime is the same as Time.fixedDeltaTime inside FixedUpdate.

[timid dove]

How are you doing camera following?

[sharp gale]

With cinemachine

[timid dove]

what's the update mode on the brain set to?>

[sharp gale]

the default values i believe

It's a really rapid micro stutter

the camera itself moves smooth in both cases; but when the character movement occurs in FixedUpdate it micro stutters.

[civic gale]

I have a scene and script in which i can drag an object along the X axis which works fine. The problem is it will go straight through other objects. I'm not sure why as im using rigidbodies and colliders. Any help is highly appreciated

objects physics components: https://gyazo.com/97ce729c7942bb7825106527d5575ba8

dragging script:

using System.Collections;
public class MouseDragX : MonoBehaviour
{
    bool dragEnabled = false;
    Vector3 dragStartPosition;
    float dragStartDistance;
    void OnMouseDown()
    {
        dragEnabled = true;
        dragStartPosition = transform.position;
        dragStartDistance = (Camera.main.transform.position - transform.position).magnitude;
    }
    void Update()
    {
        if (Input.GetMouseButtonUp(0) || Input.GetMouseButtonUp(1))
        {
            dragEnabled = false;
        }
    }
    private void OnCollisionEnter(Collision collision)
    {
        Debug.Log("collided with+ " + collision.gameObject.name);
    }

    void OnMouseDrag()
    {
        if (dragEnabled)
        {
            Vector3 worldDragTo = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, dragStartDistance));
            transform.position = new Vector3(worldDragTo.x, dragStartPosition.y, dragStartPosition.z);
        }
    }
}```

[frigid pier]

If you want collisions to work you need to use Physics methods to move it and inside FixedUpdate.

[timid dove]

yeah you're just teleporting your thing

completely bypassing the physics system

[civic gale]

oh

ok let me go back and try to use rb.moveposition

[frigid pier]

Rigidbody.MovePosition does similar thing only within physics system.

Don't forget FixedUpdate

[timid dove]

Yeah you can make that work by:

• setting a target position in OnMouseDrag
• MovePosition-ing to that target position in FixedUpdate()

[civic gale]

alright ill try that

[civic gale]

took a break and then tried that solution

still goes through the other object even though it shows that it has collided

using System.Collections;
public class MouseDragX : MonoBehaviour
{
    public bool dragEnabled = false;
    Vector3 dragStartPosition;
    float dragStartDistance;
    Vector3 worldDragTo;
    Rigidbody r;
    
    private void Start()
    {
        r = GetComponent<Rigidbody>();
    
    }
    void OnMouseDown()
    {
        dragEnabled = true;
        dragStartPosition = transform.position;
        dragStartDistance = (Camera.main.transform.position - transform.position).magnitude;
    }
    void Update()
    {
        if (Input.GetMouseButtonUp(0) || Input.GetMouseButtonUp(1))
        {
            dragEnabled = false;
        }
    }
    private void FixedUpdate()
    {
        r.MovePosition(new Vector3(worldDragTo.x, dragStartPosition.y, dragStartPosition.z));
        if (dragEnabled == false)
        {
            
        }
        
        if (dragEnabled == true) {
    
            
    }
    }
    private void OnCollisionEnter(Collision collision)
    {
        Debug.Log("collided with+ " + collision.gameObject.name);
    }

    void OnMouseDrag()
    {
        if (dragEnabled)
        {
             worldDragTo = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, dragStartDistance));
            //transform.position = new Vector3(worldDragTo.x, dragStartPosition.y, dragStartPosition.z);
            //r.MovePosition(new Vector3(dragStartPosition.x, dragStartPosition.y, worldDragTo.z));
        }
    }
}```

https://gyazo.com/ca3af849ac62e2836e773fa8723f8de0

[timid dove]

If the other object is a dynamic body it won't stop your kinematic one

only a static collider or another kinematic body would stop it with MovePosition

[civic gale]

even if i make them both kinematic it still goes through

[frigid pier]

If you want something to be affected by physics set it to dynamic

And make sure you didn't turn on positional constraints on the other object.

[civic gale]

if i dont have and positional constraints on it how do i stop it from moving

now they collide but the blue object moves away

[frigid pier]

So set it to kinematic.

If you are doing it correctly, dynamic object you are moving with MovePosition will never push in into another collider. Dynamic forces will always push it out.

[split hill]

Can anyone tell how I would do something like how Paint the Town Red has their characters set up? Is it just as simple as basically doing environment voxel destruction but adding animation and ai to it, or is there something more? I am very new to unity, and coding in general.

Please @ me if you have anything.

[chilly talon]

Hey guys, I kind of want to use the inbuilt friction/materials system but I am having an issue where whenever my character hits a wall, I lose all momentum

My goal is to move horizontally at lets say 10f

and when I hit the ground, continue at 10f

then slow down according to friction

but what happens is when I hit the ground, all momentum just stops, feels like the character gets stuck in the ground a little bit even

anyone know how I could fix this?

[torpid fossil]

Have you tried working with Physics Materials?

[chilly talon]

That's what im using

[torpid fossil]

Ah yes I see now

[chilly talon]

eh I'll continue to implament my own, feels nice

[torpid fossil]

What are your settings for the physics material?

[chilly talon]

2D btw

[torpid fossil]

You might need a friction value of 0 to make it work

[chilly talon]

oh wait

[torpid fossil]

(also don't forget to apply this to the object because I just did)

[chilly talon]

so I do have friction 0 for my own implementation

but I wanted to try and use the inbuilt one

but the only problem

When falling into the ground, the character just sticks the landing

[torpid fossil]

What kind of friction does the ground have?

[chilly talon]

oh

inbuilt so probs 0.4

[torpid fossil]

I'm asking because 3D physics materials have the option to set whether you want to be able to combine the friction by average, multiply, use the highest value, or the lowest value. Since the 2D version doesn't have that, it's hard to tell what it's using... Probably Average though.

[chilly talon]

ah dam

well 0 friction on ground is the same as 0 friction on character

I want it to hit at 0 friction, then just go back to normal

in a sense

[torpid fossil]

Oh, huh... I have an idea: you might be able to switch the physics material out at runtime.

[chilly talon]

Just whenever I collide I set the player material back to the inbuilt?

[torpid fossil]

Keep a reference to 2 physics materials: regular friction and 0 friction. Then after the period in which you want the object to experience 0 friction, switch the 0 friction material out for the regular friction physics material.

[chilly talon]

actually my idea is a little dodge

Maybe I could

would it be better to set my own friction if I am gonna go that way?

[torpid fossil]

If you alter variables in scriptable objects, it changes that value for every object that uses it so using 2 materials might be the way here

[chilly talon]

instead of using the inbuilt system?

[torpid fossil]

Yea, just to have as much control over it as possible

[chilly talon]

(eg hspeed *= 0.99)

Yeah that's fair

[torpid fossil]

Oh you're not talking about friction here right?

[chilly talon]

imma stick to mine then

[torpid fossil]

oh nvm

[chilly talon]

Ah, that applies when grounded

[torpid fossil]

I get it now I was a bit slow

[chilly talon]

all g

I have one more issue tho....

[torpid fossil]

Yea I'd go with built-in.

What is that?

[chilly talon]

https://imgur.com/a/fGL1c8o

Watch this

I hit the wall on the left

land straight down

jump straight up

land straight down

jump and HIT?!? AHHH

CircleCollider

[torpid fossil]

oh that is strange

[chilly talon]

I was using square, but I am interested in having slopes

so I switched to circle

got any ideas or just no idea?

me stump

I can think of maybe some workarounds, but idk why it's a problem to begin with

[torpid fossil]

Do you make the object stick to the wall using force? Maybe that it gets pushed like 1 pixel to the left in some cases when leaving the wall from the bottom?

[chilly talon]

So with me using the step frames

I am pressing no buttons

it doesn't stick to the walls by force

It just changes sprite when within 0.1f of the collider

[torpid fossil]

That is strange

No clue what could be causing that

[chilly talon]

it feels like the collider is going into the wall slightly so when I jump up I hit it from underneath

[torpid fossil]

Although, the Unity physics engine is not flawless. It might be a miscalculation on the collision.

[chilly talon]

how can do a flawless?

[torpid fossil]

That's internal Unity code, nothing we can do about it unfortunately

[chilly talon]

aw

maybe I'll push it 0.01f away from the wall....

[torpid fossil]

You could perhaps write code that corrects this behavior

Yea like that

If it chips the wall but the player intends to slide along it you can just push it back against the wall

[chilly talon]

is rb.position any good?

[torpid fossil]

If you change rb.position it will probably still maintain its momentum

So you'll have to set velocity (or apply force) as well

[chilly talon]

that should be okay

Ill just, whenever I hit

[torpid fossil]

This might be something pixel-perfect that only happens in this specific situation though, so if you don't find an immediate solution, don't stress too much about it I'd say

You can always come back to it if it bothers players more often

[chilly talon]

I had pixel perfect collisions before but I was using transform.position lmao

lol that's true

since I check for collisions at 0.1f

if im within 0.01f, ill just push me out a lil

[torpid fossil]

Yep

[chilly talon]

oh my goodness does rb.position add velocity..??

[torpid fossil]

I... am not aware of that?

Does it?

[chilly talon]

uhhhh?

[torpid fossil]

I thought it just set the position

[chilly talon]

hmm I might have coded it wrong

[timid dove]

No it doesn't

[chilly talon]

found the fix, had to lower fixed time step from 0.016666 to 0.01

[chilly talon]

that^^

[torpid fossil]

Alright!