#⚛️┃physics

1 messages · Page 63 of 1

thorn ferry
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Does anyone know why this happens? I already set the player collision detection in continuous, and the cube has box collider

📎 gif.gif
snow cove
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    {
        RaycastHit hit;
        if (Physics.Raycast(PlayerCamera.transform.position, PlayerCamera.transform.forward, out hit))
        {
            Debug.DrawRay(PlayerCamera.transform.position, transform.forward, Color.magenta);
            Debug.Log("Did shoot");
            Debug.Log(hit.transform.name);
            Debug.Log(hit.transform.position);
        }
    }```
#

Can anyone tell me why my ray casts aren't visible?

glacial jolt
#

Time.deltaTime is used to make things "framerate independent". So transform.position += Vector3.right * Time.deltaTime in Update() moves something 1 unit to the right per second, regardless of whether you are running at 30fps or 60fps or 60000fps

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in FixedUpdate you accomplish the same with Time.fixedDeltaTime

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AddForce and similar methods do not need it, they automatically apply it

modern laurel
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Is it possible to use rigidbody to do movement like you would with Lerp?

viral ginkgo
#

@modern laurel you gotta give more detail on what you want

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you should be fine setting velocity however you want

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you can also limit how much the velocity can change per frame in your code if thats something you may want

modern laurel
# viral ginkgo <@!184487894457516032> you gotta give more detail on what you want

I'm really new. I have this code, but because i'm not using physics movement, the coins on top of the pusher are not moving with it. I read that it's because if I want that interaction I need to use rigidbody to move. https://pastebin.com/jz02YfVJ

Pastebin
using System.Collections;using System.Collections.Generic;using Uni...

Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time.

viral ginkgo
#

@modern laurel is this your project?

modern laurel
#

ye

viral ginkgo
#

or you want to make the same thing

modern laurel
#

live right now lol

viral ginkgo
#

yea i see

modern laurel
#

the coins aren't moving with the pusher

viral ginkgo
#

well it looks like they do?

modern laurel
#

they're floating on top of it

viral ginkgo
#

oh i understand

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you have to move pusher with physics

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heres what you can do

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make a kinematic object, call it PusherHandle or something

modern laurel
#

right, but like, will the physics items there push it back, or is it possible to move it while it's clipping through walls and such

viral ginkgo
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Make your current pusher into a dynamic rigidbody

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attach them to eachother via a fixed joint

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and move the kinematic body the same way

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with the transform

modern laurel
#

ooh

viral ginkgo
#

you get it?

modern laurel
#

yeah

viral ginkgo
#

what kinda stream is this

modern laurel
#

that's off topic lol

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i'm open to DMs though, not here to advertise

modern laurel
#

So, i hooked up a new object and it's working great, but for some reason everything is drifting to the right now doing some troubleshooting myself brb, the object I made in blender was not fully straight, so that explains it lol. using a primative fixed the drifting

modern laurel
#

is there a way to remove momentum?

tender gulch
#

Yes. One way is to move your object with velocity instead of adding force.

modern laurel
#

ah, it's a coin pusher. not sure i can do that

lean skiff
#

Hi, I'm trying to make the physics/animation of the vehicle driving around feel more realistic, and not so stiff. I want to make driving feel cooler. Do any of you have any tips?

📎 bSybKNZvlR.mp4
solid sluice
lean skiff
#

ohh

lean skiff
native trench
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hey so im trying to get a very 'stiff' solid connection between rigidbody cubes, what would the best joint be? I tried fixed but it bent a bit

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basically want them to act as a solid model until I get a collider hit and then I will let them 'break' up

glacial jolt
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@native trench fixed joint should work for your purposes, but a configurable joint with all axes locked would also work

glacial jolt
mild goblet
#

How would I make my circular object decelerate? it spins in both directions. I commented out stuff that I tried. I want to make a smooth acceleration and deceleration.

📎 DecelerateHowDoI.JPG
tender gulch
royal lily
#

ayo, nothing really to do with coding but uhh how do i do a detailed analysis of how instantaneous speed is measured On a bicycle using an analog device (non GPS)

twin monolith
#

is it possible for my partical system to effect my player speed. if so how because it's the last thing i implemented before bed and now it's slow as hell. any ideas guys?

timid dove
rough wraith
#

Hi, I am currently working on a VR game using OpenXR in unity 2020.4. I have created a physics system for both the VR hands and body but the problem I am having is that when I press play the hands collide with the body and throws it off of the map. I am trying to get the body and hands physics systems to ignore each other so this is no longer an issue, but I have looked through documentation but I couldnt find anything that worked for me. Any help would be great!

supple sparrow
rough wraith
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@supple sparrow Just sorted that problem thanks, but now my issue is that I have a rigidbody on the XR rig for the full body physics, but when I am in VR the head jsut falls into the ground (The head is currently represented by a sphere and the body is a capsule.) Is there any way that I can have the shpere ignore the rigidbody without taking the rigidbody from the xr rig?

stuck yarrow
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So to explain my problem that I am having: I want the player's rotation to follow the direction of movement. However due to the spherical gravity used in my project, angles and movement is made x10 more complicated...

Currently I have a gameobject within the player that follows its movement. This gameobject will move up and down when the mouse moves up and down and it will also move left to right when the mouse moves left to right. The camera then follows the rotation of this gameobject and is offset a certain distance from it. The player's transform is separate to the rotation of the gameobject - and it is crucial that this gameobject is parented to the player since it allows me to skip some steps with the spherical gravity.

Here are the 3 main scripts that allow this to happen and I was wondering if anyone could give me suggestions on how to do this, because it is really confusing. Any help would be greatly appreciated:

FPController: https://hatebin.com/dsfsshdfta
CameraFollow: https://hatebin.com/rbglwlztos
GravityBody: https://hatebin.com/czafvrfahj

twin monolith
stuck yarrow
#

I know the pain too lmao

maiden comet
#

Hey, guys, do cloth colliders collide with eachother?

foggy rapids
# twin monolith any1?

Anything is possible if you put your mind to it.
For something to "effect player speed" it'll have to be part of your player control system regardless. Your particle system might define an area inside which the player decelerates and ALSO spawn particles in there. 🤷

foggy rapids
stuck yarrow
#

What don't you get? @foggy rapids

foggy rapids
#

what are you asking?

twin monolith
#

@foggy rapids hey and thanks for answering, it was working ok two days ago, after that evening of working the day after my player went extremely slughish, i've reduce the mass and drag down to a silly amount, however i don't think i should be doing this as it was working ok before hand. so far i've only implimented megawhatts bolt controller which worked perfectly. since then i've created the jumping, however not implimented yet, as not yet created the animation. i did also add some bubbles, 3 partical effects on the bodies head. which also worked. any ideas where i may have clicked what i shouldn't have. i'm pretty new

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in short i've had a working model and now extremely slow. i've also reduced the rigidbody mass and gravity to compensate. but still extremely slow. any clue?

stuck yarrow
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I don't know how to face the player in the direction of movement. It sounds simple, but the player is always rotated at weird angles anyways, so it is difficult to rotate the player as such so that it faces the direction of movement

foggy rapids
twin monolith
#

indeed

foggy rapids
twin monolith
#

nope

foggy rapids
twin monolith
#

i'm using bolt and using the velocity movement, why because i'm under water

stuck yarrow
#

oo ok, I will have a look now

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thanks

twin monolith
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i think it's not the code button something else. in the settings. unsure as to what tho

foggy rapids
#

you can use transform.LookAt(moveDir * 50) as long as 50 is bigger than the volume the player takes up

stuck yarrow
#

ah right, ty!

foggy rapids
twin monolith
#

question would particals push my player down if they are going upwards ?

foggy rapids
#

particles shouldn't do anything unless you gave them rigidbodies and your player also has a rigidbody

twin monolith
#

yea i didn't think so either. that was the last thing i did before saving and ending that night,

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last working state

foggy rapids
#

i think the best i can do is recommend using git or any version control system so that in the future you can go back to yesterday 😄

twin monolith
#

ok cool, yea maybe

gilded blaze
#

there is a particle module for particle collision events... it's probably possible to use that to implement forces from particles hitting your object, but can't say anything about what sort of performance you can expect

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(in most cases, adding forces manually along with the particle vfx is the better solution anyway)

mild moss
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Is it possible to have premade animations that also account for physics

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i'm trying to go for smash bros like attacks but I also want to incorporate a kind of stickfight the game-esque feeling

stuck yarrow
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How would I rotate the player on Local Euler Y Axis, when there is also a quaternion taking place on the player at the same time? It sounds complicated - I know - but here is why:

I am working with spherical gravity and the script that keeps the player onto the sphere uses this: transform.rotation = SmoothDampQuaternion(transform.rotation, targetRotation, ref currentVelocity, OTS); to rotate the player onto the sphere. However since I am also working with the camera movements of the player, I need to rotate the player on the Y Axis, whilst it is orbiting the planet

timid dove
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by which I mean the direction directly away from the planet's center through the player

stuck yarrow
#

alright I will have a try now

timid dove
#

why would you do that though?

stuck yarrow
#

do what?

timid dove
#

that code

stuck yarrow
#

o

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what should I have done?

timid dove
#

rotate it around its local up axis or the direction away from the center of the planet

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that just sets the Y euler angle to 50

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which... ignores all of that

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that will rotate it around its own up axis by 50 degrees

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one time

stuck yarrow
#

oh ok

timid dove
#

Or if you want to do it in Update:
transform.RotateAround(transform.position, transform.up, 50 * Time.deltaTime);

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50 degrees per second

stuck yarrow
#

ahhhh I see now, thanks!

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i never knew that existed lmao

timid dove
#

there's all kinds of goodies in the Scripting Reference

stuck yarrow
#

well I will make sure to be looking there next time then, since that would have saved me 7 hours worth of thinking

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i guess that is the thing with learning to code, you waste time in the beginning and then realise that you could have done that thing within a few seconds

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but thank you anyways!

long radish
#

Hi,

Working on our game I've found the issue described here:

https://forum.unity.com/threads/interpolation-doesnt-work-when-simulating-physics-manually.676489/

Using a manual simulation (calling Physics.Simulate() during an update cycle) the RB interpolation is not working. I suppose this happens because the engine handles RB interpolations between FixedUpdate() and Update() cycles. Is it correct? Any idea for a workaround?

Unity Forum
Interpolation doesn't work when simulating physics manually

This may be expected behaviour, but it has caught me out - I'd like to understand a bit more about it if anyone knows:

When I use...

arctic marsh
long radish
arctic marsh
long radish
#

The problem is that normally FixedUpdate is called before the physics step, and it's perfect for Pre-Physics logic, but there are no entry points for a Post-Physics callback

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Anyway, the main problem is this: if we manually call Simulate, in a way similar to the one described here

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the interpolation doesn't work

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In terms of Execution Order, I can't find any detail about the RB interpolation - when is it executed? From our tests it seems that Unity interpolates RB after the PhysX step and before the Update cycle. If it's the case, I suppose that is not possible to interpolate RB when running Physics.Simulate() during Update

timid dove
#

Never found a solution

long radish
#

😄

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The only solution I can see is to run Physics.Simulate() during FixedUpdate - executing a single step for each FixedUpdate call

arctic marsh
#

But this is somehow doubling the physics simulation, isnt it? 😄

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But maybe, thats the only way if there is no hook upfront or after to use

long radish
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No, we're not "doubling" the simulation, because we've disabled the automatic simulation step. We're simply controlling it in our flow 🙂

Any other suggestion? It's very strange that the engine doesn't support interpolation with Physics.autoSimulation turned off

arctic marsh
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Oh okay, you disabled it, alright. Well if its off, it is off, right? Guess thats just decision of design here

long radish
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Mmm, I don't think it's a decision related to design. We're simply controlling when the Physics.Simulate() is called - I don't think that this should compromise the RB Interpolation. In any case, this detail is not documented at all

arctic marsh
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So Physics.Simulate is not accounting RB interpolation, right?

long radish
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No - that call only wraps a PhysX step. From what I see I suppose that RB Interpolation is handled somewhere internally between FixedUpdate cycle and Update cycle, but I can't find any detail about that

timid dove
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I think the problem is that Rigidbody interpolation is a completely black box and apparently tied into the automatic update cycle with no visibility in the API at all

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As far as I know you can't even manually do the interpolation either because the rigidbodies also get synced automatically to transforms?

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Or is there a way to turn off automatic transform syncing too?

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🤯

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maybe this is the key?

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Turn this off, and do the syncing of the transform manually from the rigidbody position before and after physics sim?

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or is this actually only the Transform -> RB sync and not the RB -> Transform sync

long radish
#

I don't think that autoSyncTransform is usefull in this context. That flag is used in order to control the propagation FROM Transform TO RB, not vice versa

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I think you got the point - there's no way to do manual interpolation using the built in rigid body

timid dove
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T_T

foggy rapids
#

you don't have to use built-in rigidbodies. How complicated is your physics? You might be able to use a separate physics library altogether or make your own

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If you wanted before/after callbacks you can implement your own fixedupdate as well just using update

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but yeah that's a tough one 🤔

distant coyote
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you can also use multiple Physics scenes too

timid dove
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Would that somehow help the interpolation problem?

distant coyote
#

whats your interpolation problem?

timid dove
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uhh... the whole discussion above 😄

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when you manually call Physics.Simulate(), Rigidbody interpolation doesn't work

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(for rigidbodies set to interpolate)

distant coyote
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its part of autoSimulation

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the Interpolate setting on rigidbodies is Transform --> RB

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you can easily do the interpolation yourself in Update or LateUpdate

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what pisses me off the most about Unity is that the default physics rate is 50hz

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what is this? PAL TV and mains frequencyland?

long radish
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You can't do a custom interpolation because you can't move the transform without affecting the next physics step. Maybe it's possible to move the transform and then move it back in the next FixedUpdate, but is seems a dirty workaround

timid dove
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Or will it still sync when you run Physics.Simulate()

distant coyote
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(taking a deeper dive into this one for reasons...)

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in real PhysX y ou could totally do this. in Unity you basically cant

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you'd need a proxy object

long radish
timid dove
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oof

hexed spruce
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hello

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çi'm ghaving some problem with the colliders

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i guess is the collider

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but i'm not sure

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i have a cube as a ground

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with z 1000 and x 15
the player is another cube

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i'm truing to make infinite map

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so i generate the ground over and over

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the problem is when i reach the end of the first "ground"

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my cube stop

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i guess is the colader

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but 'm no really sure

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idk whe the cube stops

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any idea?

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also some weird gliches like the ground i collided with another thing,

📎 unknown.png
hexed spruce
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i'm stuck for two hours in this...

foggy rapids
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it's probably stuck on the gap between colliders

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using a sphere or capsule may help, otherwise you might need some code to actually grow the collider. In most infinite runners the path moves along beneath the player but the collider doesnt so he never has to leave the collider he's sitting on.

hexed spruce
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any guide?

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if i move the ground still ned to create new one

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the ground size is 1000

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the only fix i found, but its kind bad

        this.nextPosition.y -= 0.01f;
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I switch to mesh collider, select plane mesh and mark convex and now seems working

gentle kraken
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Can anyone help? My 3d model character falls through the terrain when a rigidbody is applied, I've tried adding a capsule collider to the character but still falls through for some reason.

timid dove
gentle kraken
maiden pawn
#

I'm trying to make a sprite jump but whenever I add ForceMode2D.Impulse, it doesn't move compared to if I just left the forcemode it out
Could anyone advise me on what to do?

unknown.png
timid dove
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wait

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nvm

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that's your own custom CharacterController not the builtin Unity one. Carry on

maiden pawn
#

Ahh, did think it was for a moment too, hahah

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Thankyus

timid dove
#

anyway the reason it doesnt move with Impulse vs normal force is that you have too little force I'd say

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Since your mass is .1

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Forcemode2D.Force is going to have 10x greater effect than the same force vector in Impulse mode

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if you mass was 1 they would have the same effect

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and if your mass was 10 then Impulse would have 10x greater effect than Force

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These two will do the same thing:

Vector3 force = new Vector3(1, 0, 0);
rb.AddForce(force * rb.mass, ForceMode2D.Force);
rb.AddForce(force, ForceMode2D.Impulse);```
maiden pawn
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Ohhh, right, I thought it was the other way around

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I'll give that a shot now

timid dove
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it's sort of "reversed" because your object's mass is less than 1

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normally Impulse moves the object MORE, but only if the mass is > 1

maiden pawn
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Yeah that makes a lot of sense

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I changed the mass to 10 and jumpforce to around 1000 but I'm still getting no movement for some reason

timid dove
maiden pawn
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Yeah, I put a debug log in the function after the add force, and it comes up in the console

unknown.png
timid dove
maiden pawn
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Ah yeah sorry I updated the code after I posted it

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Waaaait just a moment, I've just fixed it, the fixed update must've been messing up something, I got rid of it and the impulse force works now

timid dove
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oh.. yeah if you're doing MovePosition that will overwrite the force stuff

viral ginkgo
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How are raycast stuff handled in kinematic character controllers?
I'm thinking do a couple raycasts from within the collider, towards movement direction.
And then do the same thing treating the gravity as movement direction.

Can i go wrong with something like this?

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Hm, if i choose a raycast origin at the tip of the feet, the character wont be able to climb tiniest slopes

viral ginkgo
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How many raycasts per frame is needed to archieve a nice kinematic controller?

verbal cargo
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Hey, I was wondering if there were any resources I could read up on figuring something out regarding colliders on ramps.

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I currently have this issue where a sphere will bump over the corner of a ramp (at the top) instead of smoothly falling off by just going forward:

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The ramp itself is positioned through scripting to be attached to the top platform, but I guess the collider is still detecting the normal of the corner of the ramp and causing the bounce to trigger there

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I tried creating the same scenario using the ProBuilder tools and seem to get the same results

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(In the image, red is the current result, green is what I ideally want)

foggy rapids
#

you could make the ball heavier

oak saffron
#

Hey, I have an issue with the foreach loop. The code is supposed to send a raycast from each connector to see, if it hits a true gate. However I know that only one raycast is sent which is prompted by the console that hit doesnt exist in the second run as well as the debugray draws only once. I'm out of ideas on how to fix that ;c

Here is the code on pastebin https://pastebin.com/uA3TbBUP

Inb4, the connectors a loaded okay, the code goes as expected but only the raycast is not send as i even get an output in console that the hit variable does not exist in the second foreach run

foggy rapids
#

your link doesnt work

verbal cargo
# foggy rapids you could make the ball heavier

Thanks for the reply. That wouldn't solve the issue of the collider responding to the normal, but I'm realizing this issue is the same as the more general one of having two floor objects connecting and colliders reacting to the seams inbetween. So I'm gonna try looking at how people tackle that.

supple sparrow
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did you try putting the ramp collider down a lil' bit ? like .1 unit. So it kinda falls on it. Yeah kinda hacky and might not solve your PG case

torpid locust
#

I have a trouble with rigibodies it drives me crazy

rigid.AddForce((SpellCaster.transform.position - Target.transform.position).normalized, ForceMode);

This code launch the projectiles exactly flipped. Both should hit the red cube in the angle.

So I just put a minus before the vector and :

rigid.AddForce(-(SpellCaster.transform.position - Target.transform.position).normalized, ForceMode);

It just fire both of the laser right in front. Everytime I try to rotate the setup to make it fire at the right place the lasers just merge on the vector forward which is totally no intended

unknown.png
#

Do you guys have an idea of what could cause this issue ?

verbal cargo
verbal cargo
torpid locust
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Found out my problem was multiple instantiation, they collided all together at starting position. And because of the the impulse on the addForce messed up because of the collision

unknown.png
#

Now it works

verbal cargo
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Oh nice 👍

torpid locust
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Thanks though @verbal cargo !

foggy rapids
shy onyx
#

Question: how do I stop cold instead of "decelerate" with a rigidbody? Also, I'm trying to turn left, then keep walking forward, but as it is, this only allows me to walk forward and back, even when I'm facing the other way (or left / right).


if (_moving)
        {
            // Move
            Vector3 Move = new Vector3(0.0f, 0.0f, move.y) * Time.deltaTime;
            _rigidbody.AddForce(Move * 800f);
            
            
            // calculate the distance and stop 
            moveDistance = Vector3.Distance(transform.position, prevPos);

            

            if (moveDistance > 0.5f)
            {
                _rigidbody.velocity = Vector3.zero;
                _rigidbody.angularVelocity = Vector3.zero;
                _moving = false;
            }
}

Trying to do a legend of grimrock type of walk

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But I've stumble upon this issue, mainly because I still do my math with my fingers and this is physics.

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btw, I'm using rigidbody only because I want a collider (walls, doors, etc). I tried using a raycast, but it got me nowhere but to the drugstore for aspirins.

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if I do transform.translate, it works, but I have no way of stopping before a onEnterTrigger collider without clipping like Casper the friendly ghost all over the place.

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Should I quit and go ask my uncle for a job at the gas station?

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GOOD NEWS! I Solved it myself!

In case someone comes with a similar issue: I needed to use AddRelativeForce, not ``AddForce`.

Bad news: I have to start pumping gas on Monday now.

distant coyote
#

@shy onyx use Lerp, MoveTowards, etc.
_rigidbody.velocity = Vector3.Lerp(_rigidbody.velocity, Vector3.zero, Time.deltaTime * 10); //replace 10 with a variable or some number that works for you

shy onyx
#

any way to stop cold instead of sliding like if I was on ice?

distant coyote
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just set velocity to zero

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or .isKinematic = true

shy onyx
#

thank you man, you've got yourself a free gas coupon.

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Why is my rigidbody dragging like a snail? I'm adding a high velocity number and still drags like a snail!

Vector3 Move = new Vector3(0.0f, 0.0f, move.y);
_rigidbody.velocity = Vector3.Lerp(_rigidbody.velocity, Vector3.zero, Time.deltaTime * 650); //replace 10 with a variable or some number that works for you
_rigidbody.AddRelativeForce(Move);
distant coyote
#

_rigidbody.velocity = Vector3.Lerp(_rigidbody.velocity, Vector3.zero, Time.deltaTime * 650)
This will reduce your RB's velocity to zero very quickly

timid dove
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Unless your game runs at about 700 FPS+ Time.deltaTime * 650 will always be greater than 1

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Therefore Vector3.Lerp(_rigidbody.velocity, Vector3.zero, Time.deltaTime * 650); will always be equal to Vector3.zero

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Well, unless this is in FixedUpdate, in which case Time.deltaTime * 650 will evaluate to 13 every time regardless of framerate (unless you changed your fixed timestep)

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Which will also give you Vector3.zero from the Lerp

modern laurel
#

I'm going to sleep, but I want to know if there's a way to make my coins stop flinging into the air. I have gravity to 20 and static friction to .01 (so it should be easy to push the coins) but they still get flung into the air pretty often. Here's a clip, it's the silver coin on the right https://clips.twitch.tv/AwkwardProudCatDatSheffy-Q3-7XJ78lz7c3WZS

rose arch
#

hello im new and im trying to make a multiplayer game but im struggling could anyone help me

viral ginkgo
#

Your tried pulling the fixed deltatime to small values? @modern laurel

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@rose arch new to unity?

rose arch
#

yes

viral ginkgo
#

got programming exp?

rose arch
#

no just new to coding and unity

viral ginkgo
#

people will probably suggest following a plain c# tutorial without unity context first

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gotta get some basics down

rose arch
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i got variables using brackeys tutorials

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i mean

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learnt

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ye my english is kind of bad

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anything wrong?

viral ginkgo
#

make sure you can write and understand some c# code
the lists, arrays, loops, conditionals, classes, objects etc

then you could make a small consoleapp project for practise

then you do some basic unity tutorials
learn stuff like gameobjects, components, raycasting, collision detecting, referencing stuff via public fields etc etc.

then you make a small, simple game or just keep building on top the tutorials code

and then you choose a networking asset, (i recommend mirror).
do some tutorials to learn about RPCs, Commands, maybe use some of the built in components

then you should have all you need to start a simple multiplayer project

#

@rose arch

rose arch
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but the codes are different arent they?

viral ginkgo
#

if you dont have intermidiate experience in programming, you will just have a hard time in unity

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if you dont know most of the unity's basics, you will have a hard time making a game

rose arch
#

ok so i have to start learning how to write a C# script and then start everything else right?

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and understand

viral ginkgo
#

yes,

#

doesnt even have to be c#

rose arch
#

ik python

viral ginkgo
#

java exp translates well to c#

#

very good

rose arch
#

ok

#

ill have to go

lethal wyvern
#

Am having a problem with bullet(Rigidbody). If i use OnCollisionEnter it works perfectly but my bullet needs to go through the player collider (Capsule Collider) in order to hit the enemy body parts.

#

So i am using OnTriggerEnter but my bullets move at a speed of 1000(Add Force units,Impulse) so they cant detect the collision but they do detect in low speed. H E L P ! ! ! ! !

#

I tried adding a raycast to them but that also didnt work(Raycast on the bullet prefab)

#

Just in case

supple sparrow
#

I would still use a collision, not a trigger

#

and solve that player collision problem

#

you could put your player and bullet prefab in different layers for example

lethal wyvern
supple sparrow
#

If i understand well what you describe, yes

#

hope I understood it well :p try it

#

but that's also strange that your bullet collides with the player in the first place 🤔 should not happen

#

you should shoot from a "barrel tip" gameobject, offset in front of the player

lethal wyvern
#

Sorry for the nudity there

Cubic_Frost_Multiplayer_-_GunPlay_Mechanics_-_PC_Mac__Linux_Standalone_-_Unity_2020.1.10f1_Personal_.png
supple sparrow
#

NOT from player's position

lethal wyvern
#

i need to hit his internal colliders

supple sparrow
#

oh player and enemies have capsule collider + body part collider ?

lethal wyvern
#

its kind of a multiplayer

supple sparrow
#

yeah just put the capsule collider in another layer than the bullet prefab, should be enough

#
  • adjust layer matrix
lethal wyvern
#

so if i put the capsule collider and in another layer and enable collision (Disable istrigger) on the bullet the bullet will be able to go through the capsule collider but hit the internal colliders

supple sparrow
#

yes

lethal wyvern
#

Thanks Mr.K

#

Never knew that was possible lol

supple sparrow
#

you're welcome, happy coding 👍

vivid hull
#

does anyone know how to fix rigidbody characters sticking to walls

lethal wyvern
#

It works like a charm thanks Mr.K

summer fog
#

So I'm trying to move objects into subscenes with physics, I'm dynamically creating scenes using the scenemanager and moving the game object I care about into them once they finish loading

#

but the problem I'm having is that the transform of that moved game object seems stuck

#

I can see forces being applied and dampened on the attached rigid body

#

but the object never moves or rotates

#

anyone have any idea what I might have missed?

#

The fixed update method on the game object is being called, and I'm simulating the child subscene's physics from the parent

#

should say that in the parent scene the object does move around

#

if I don't slide it into the child

timid dove
summer fog
#

I move the entire object

timid dove
#

I've never done multiple physics scenes so forgive me if that doesn't make sense

summer fog
#

so I move the parent

#

and that parent has the rigid body

#

so the rigid body + the thing being rendered are in the physics scene

modern laurel
viral ginkgo
#

@modern laurel maybe you can just lock coins x-z axisces

#

after they havent been sitting flat for some time

cold rivet
#

im getting this wierd issue where this ball get stopped by nothing

#

its trying to move to the right, but it stops right there

#

ive tried clicking there, but nothing shows up

timid dove
#

It looks pretty angry

#

maybe it's just sick of following your directions

cold rivet
#

im pretty mad too

timid dove
#

Or maybe there's a collider there

cold rivet
#

hes about to get the delete key

#

and how do i tell if theres a collider there?

timid dove
#

Couple things youc an do - add an OnCollisionEnter and print the name of what it hit

#

or just search your scene for cxolliders

#

t: Collider

#

in the hierarchy window

#

and look at them all

cold rivet
#

like that?

timid dove
#

yes except... this looks like 2d right?

#

So

#

void OnCollisionEnter2D(Collision2D col)

cold rivet
#

ohhh right, that makes sense

#

i was able to fix the issue, thanks Praetor

west geyser
#

need a little help

tender gulch
west geyser
# tender gulch With what?

I added a box into the scene and a capsule as player but the capsule isn't colliding with the cube it just falls through it

tender gulch
west geyser
tender gulch
# west geyser nope

Then I can't think of anything that could cause it. Unless you're running some code that modifies these objects at runtime.

west geyser
#

let me start from the new scene

stuck bay
#

hi does anyone know how to implement knockback my enemies in unity

supple sparrow
#

Multiple ways. Did you do a search / watch a video to see how others do it ?

summer fog
west geyser
#

im repeating the whole thing in two channels oh god

tender gulch
west geyser
#

or they just managed to get it working somehow

#

there wasn't a reliable fix

hard scaffold
#

So i just saw a video of Shell Mechanics Overhaul for Post Scriptum, and im wondering how i'd do something similar in unity, as Post Scriptum is made in UE4. I'm planning on getting a demo done for my game first and im going to add just about every mechanic i have planned by the time im ready to release my game proper.

stuck bay
#

how do i program how to push/pull blocks in unity 3D?

timid dove
stuck bay
#

wait i'll show a screenshot

stuck bay
timid dove
#

Again there are many ways

#

Object parenting

#

Physics joints

#

Or just moving the object in script

stuck bay
#

ah ok i'll probably try it

#

thx

primal thicket
#

Simple question: How can I bounce an rigidbody multiple times while decreasing it's height every time it bounces off?
it should stop bouncing after hitting the ground like ~6 times
i tried playing with the bounciness in the phsyics material but even if i set it to 1, the height is not as high as I want it

viral ginkgo
#

@primal thicket if you want real precose control on this, you cqn do your own simple physics via raycasting

#

or sphere/circlecasting

#

have your own velocity code and handle your own bouncing behaviour

#

@primal thicket or you just needed to also lower the drag in rigidbody settings

primal thicket
#

I've actually found a solution which is just adding a force each time I hit the ground

#

I multiply it by the counter and reduce the counter by 1 each time

#

I dunno if that's optimal though

#

but it definetly works

viral ginkgo
#

its probably losing its energy too fast because of drag

primal thicket
#

hmmmmm i should try to play with the drag as well

viral ginkgo
#

i think you can make it preserve its energy and pretty much bounce forever

#

if you also disabled drag

#

id also make friction 0

#

so no energy is wasted on angular momentum

primal thicket
#

on the physics material?

viral ginkgo
#

drag is on rigidbody

#

friction is on physics material

primal thicket
#

Yeah I will try to scale them accordingly. Thanks!

viral ginkgo
#

np

#

if it works, then you can adjust the velocity in OnCollisionEnter

#

you could multiply velocity by 0.9 for example

#

and that should make the bounce height to 0.81

#

if its dropped from 1 i mean

#

@primal thicket

primal thicket
#

works OnTriggerEnter too right?

viral ginkgo
#

if you multiply velocoty by 0.9, jump height should be %81 each time

#

@primal thicket OnCollisionEnter

#

triggerenter is for trigger collisions

primal thicket
#

I have both a RB and box collider attached to the gameobject, need to change it accordingly, but this should work

steel verge
#

My Physics2D.OverlapPoint doesn't work on Tilemap colliders. How can I fix this?

slow rock
#

hiya
i have a quick question

so i have a breaking script( snippet) on my rigidbody veichle
https://hatebin.com/jqipdqpkbz
it works fine when i move it and it needs to brake but if i drive up a slope it slides down regardless
how to make it stop the sliding down without modifying other the drag and friction (friction doesnt work because rigidbody is floating and i dont want to modify the drag because it makes the movement and physics reactions of the object sluggish)

distant coyote
#

@slow rock Rigidbody wheels tend not to work out so well because of the nature of "Tire" physics. real-life tires aren't rigid, they're flexy and grippy and generally have 2 types of friction (lateral and rolling resistance).

#

the Wheel Collider provides a decent simulation of this as well as a suspension, steering, and motor simulation

lone tinsel
#

I'm trying to make building destruction but it is just way to laggy someone said to use a compute shader so does anyone know how to make one?

hot flicker
#

@lone tinsel its easy

#

@lone tinsel i now i easy way to do it use blender

vivid hull
#

This really isnt about the rigidbody rather the character controller, is there a way to make a jump that doesnt feel so floaty

visual scaffold
#

Does anyone know a good way to make projectiles? And I mean projectiles, not hitscan. I hear Unity’s movement system is unreliable with collisions at high speeds, but does anyone know what those speeds are? (Roughly)

timid dove
#

You can try continuous collision mode and/or doing your own Raycasts in FixedUpdate to detect obstacles

visual scaffold
#

Is it more efficient to have one script manage many game object projectiles of for each projectile to have its own script to handle its own collisions/etc?

#

Not one script for all, but say one script per “gun”

foggy rapids
#

depends on the number

#

but probably better to manage them all with one script

#

to save <number of bullets> Update calls

timid dove
#

It's really difficult to manage collision events in particular from a single script

#

Because Unity will only send collision events to the objects involved in the collision

foggy rapids
#

but it's better to put that stuff on the things getting hit

vagrant glade
#

Hey how do I change a single instance of my physics material?
Like I have a standard asset pack and I have a physics material "Bouncy" applied to two objects, how do I change the setting of one without changing the setting of the other

foggy rapids
#

use collider.material

timid dove
limpid hornet
#

I have a dumb trig question. In 2D. I have a vector 2. I want to find the clockwise angle from this point to another point. So that if the second vector2 is due east of the first it will be 90, if the second vector is due west of the first I get 270.

glacial jolt
unkempt summit
#

So I have hinge joints on my car doors, but whenever they open and then slam shut and go back to angle 0, they fucking spazz out and like fly open instantly

#

collisions are disabled on the joints

halcyon crescent
#

Quick question.
I have the player attached a capsule collider 2d and the platforms with box collider2d, when if the player hits on edge of the box colliders player bounces and if hits while jumping its velocity increases.. However if i have a box collider on player it works fine. So is there a way i can come out of this. Thanks

pine warren
#

Is there any setting to limit the minimal distance between two colliders before OnCollisionEnter gets triggered?

#

Having issues with it being called, where all contact points have a relatively large separation value (> 0.1 units)

#

Image showing the distance between the two bodies (a mesh and terrain collider)

unknown.png
#

The separation distance on all contact points in this case is 0.45 or further.

timid dove
#

You don't have wheel Colliders?

pine warren
#

Not in this case no.

timid dove
#

No other colliders at all?

pine warren
#

I'm using simple raycasts to keep it off ground (applying a force based on a simple spring model)

#

So its basically a hover-car.

timid dove
#

Have you tried debug drawing the supposed contact points from the collision?

pine warren
#

And no, no other colliders. I've double checked the collision matrix in the physics settings etc.

#

Yes. the contact points are the four corners of the bottom of the collision mesh on the car

timid dove
#

Hail mary: you don't happen to be far away from the origin do you?

pine warren
#

Nope. Super close

#

Never further away than ~150 units.

timid dove
#

I feel like something else is happening here..

pine warren
#

Tried switching to continous mode on the rigid body as well.

timid dove
#

Like maybe there's some stray geometry on your Mesh or something

#

.45 is A LOT

#

The physics engine wouldn't just be approximating by that amount

pine warren
#

I've redone the collision mesh just to be sure 🙂

#

This issue seem to be the cause for something that happens randomly. Where the car goes flying off, as if a huge force has been applied in order to separate the two.

#

happen when driving straight forward, on a terrain that is completely flat...

#

All of a sudden the car just goes into orbit (more or less). Double checked the forces I apply manually, but they dont sum up enough to make such a impact.

timid dove
#

Have you made sure it's the terrain thay you're colliding with?

#

Maybe you have some invisible Colliders you're running into

#

That you left around by accident

pine warren
#

Double checked that as well.. I only log if the layer of the colliders triggering the callback match

#

Even made a test scene, where there is only the car and the terrain. Everything else has been removed.

#

Its driving me crazy

pine warren
#

Argh, did another test scene. Started completely from scratch. And so far, not a single contact point that reports a positive separation

modest zodiac
#

can someone explain to me why this code snippet doens't work?

        Vector3 position = transform.position + transform.right * _speed * Time.deltaTime;
        Vector3 localPosition = transform.InverseTransformPoint(position);
        transform.localPosition = localPosition;

It works as expected if I assing the position variable to the transform.position. I want to understand why it breaks when I try to convert the position variable to local position. The parent game object isn't scaled nor rotated

weary dawn
#

does anyone know if ragdolls take up a significant amount of performance when they are laying still? Im asking because im wondering if i should disable ragdolls of dead enemies after a certain amount of time, or just leave them be for the rest of the level

#

will probably be around 100 ragdolls per level in total

timid dove
#

ragdolls are made of Rigidbodies

#

rigidbodies have an optimization called "sleeping" where they are removed from the simulation loop when they have been stationary for a little bit

#

but their colliders will still be there, their renderers will still be there, and they will still take up memory

#

that will all affect performance still

dim solar
#

Hi, anyone can help me with the movement in the X axis? I've tried to disable the rotation on X axis under rigidbody constraints and it didn't work

#

Heres the sourcecode

unknown.png
regal vessel
#

Hi guys, I have recently experienced an issue where my player teleports on the upper side of the Enemy whenever it gets too close. I have no idea why it is occurring though.
Regarding the setup: My player has a Character controller and a rigidbody (kinematic) components; the enemy has a Navmesh, a mesh collider and a rigidbody (kinematic) components.
I worked on fixing it by turning the mesh collider into convex and turning 'is kinematic' off. That seems to work but I need to keep the mesh collider without it being convex, since my enemy is a donut and you have to be able to shoot through its hole. Some forums suggest that changing the height of the Navmesh Agent may be able to fix it, but it doesn't seem to be the case. It doesn't work changing the Character Controller slope limits either. I tried reducing the slope limit and the step offset to 0 but it didn't work. I would really appreciate some help :D (video below shows the problem)

hearty kite
#

@dim solar Hey! I think it would be best to just not change the x and z angles if you do not need to. I would just change the targetrotation before the sleep to (rb.rotation.x,targetrotation.y,rb.rotation.z) with eulers so it does not change it during your slerp

round hinge
#

Quick question. I'm making an air hockey game. Both handles and the ball have Rigidbody set to continuous... But when handles shoot very fast, the ball goes through the handle! But not through the walls at all

#

Wall is static by the way

#

What can I do to fix this ?

#

Thanks :D

#

( and to be clear, I move the handles with one of those ForceMode s , not by changing the velocity itself )

viral ginkgo
#

@round hinge is the handle rotating by any chance?

round hinge
#

@viral ginkgo not the handle , no , but the ball is

#

Could the rotation be the issue ?

viral ginkgo
#

If you got this kind of situations that is

#

if ball is round and it doesnt rotate fast, i guess not

round hinge
#

Ball doesn't move a curved move at all

#

Only rotates around itself

viral ginkgo
#

either way, that would be solved by switching to continious sceculative collision detection that comes after continious col. det.

#

i think thats not the case though

round hinge
#

Does any of those "interpolate" or "extrapolate" could have caused this issue ?

#

Because I have set the handles as extrapolate

viral ginkgo
#

they dont change how the physics executes

#

they change how you view the transforms

round hinge
#

I see

viral ginkgo
#

also the value of transforms

round hinge
#

This is a known issue, right? I saw no answered thread online about this topic... All are unanswered

viral ginkgo
#

if you use interpolation, you should access rb.position/rotation instead of transform.pos,rot

round hinge
#

@viral ginkgo yes I know

viral ginkgo
#

i dont know whats going on, whats causing the issue

#

do you have any transform disturbances?

round hinge
#

It's the physics. And potentially my addforce method

#

I set the force mode to the third option I guess ( before the "change velocity")

#

( btw I'm also curious if the "change velocity" affects velocity directly)

viral ginkgo
#

even if you directly change velocity, it shouldnt go through i believe

round hinge
#

It's a dangerous thing to do anyway, I didn't change velocity directly at all, since I'm not physics professor and tend to keep the game real as possible

viral ginkgo
#

It says in docs that it changes velocity instantly

round hinge
#

Yes, that's why it's dangerous

viral ginkgo
#

so the effect is something cant be replicated with just Addforce

#

because addforce wont do instant velocity change

#

i dunno, maybe try doing that with addforce

round hinge
#

Sorry , I didn't get what you mean , can you be more exact at this ?(I'm not natively EN)

#

@viral ginkgo sorry I forgot to mention your id

viral ginkgo
#

@round hinge i meant you could try doing this without velocitychange mode

round hinge
#

That's what I'm doing , I'm using the other option

#

Called "explosive" I guess

viral ginkgo
#

dont put anything

round hinge
#

Ok, yeah that might help

#

And by the way, I've tried all other force modes as well

viral ginkgo
#

i think this most likely wont solve your issue but since its going to be easy to try, i guess why not

round hinge
#

Yeah I'm gonna try it. ... And mayyybe it could be because of that there are two Continuous rigidbodies colliding ? Maybe this continuous method doesn't work with itself?

#

I have a feeling that's the case , because the ball doesn't go through the wall at all . Only through the handles

viral ginkgo
#

@round hinge did you try speculative mode?

#

maybe you should do some custom here

#

i'm talking raycast based stuff

round hinge
#

Custom how?

round hinge
viral ginkgo
#

Looks like the velocity change isnt really instant

#

I dont think you'll see that rigidbody.velocity will change after appling any kind of addforce including the "velocity change" mode

#

You issue is probably because the per-frame acceleration gets too big one the rod is hitting the ball

#

because it gets slower for one frame because its got hit

#

and then you set the velocity to same value again after that

#

which makes a real high velocity difference

#

and i guess that glitches the physics

#

.
i would keep using velocity change mode
and limit how much the velocity can change per frame

#

ill give it some value so that velocity wont change more than 10.0f for example

#

with some little math

round hinge
#

@viral ginkgo yeah, that's a pretty good idea ! Thanks :D

lone tinsel
#

I made the motor Torque very high but still nothing

timid dove
lone tinsel
#

is the friction the Extremum Value

timid dove
#

friction is a property of the PhysicMaterial attached to the two Colliders that are touching

spiral turtle
#

Hello, I'm in dire need of some help with applying force (apparently I skipped that class long ago).
Problem is, I want to move my object down by applying force at points F1,F2,B1,B2 and I want my object to NOT spin at all.
So if total force I want to apply is 10 then how do I calculate the distribution on those 4 points?

unknown.png
timid dove
#

just apply 10 units of force directly at the object's center of mass

#

e.g. with the normal Rigidbody.AddForce method

spiral turtle
#

But that's exactly what I don't want to do.

timid dove
#

why

#

the net effect will be the same

spiral turtle
#

just please assume it's not the same. center of mass is the wrong way for me.

timid dove
#

you have to solve a system of equations here...

#

10 = F1 + F2 + B1 + B2
then you need to make sure the torques cancel out for each axis.

#

Torque equation is T = FD (torque is force * distance)

#

where distance is the distance that the force is applied at from the center of mass

#

but you need to do that for each of the three dimensions

#

for each point where you're adding force

#

and make sure that the x, y, and z torques all add up to 0

sleek creek
#

Hey, not sure if this is the right area. I use root animation which moves my capsule collider controlled character. However, when it comes in contact with another capsule (my character attacks an enemy with melee) the player capsule will often "slide" up to the top of the enemy capsule. And it is then...floating in the air until the capsule beneath moves.

I don't want to lock Y position because I have a jump mechanic.

I asked some animators/root motion people but they said it was a physics issue. Any ideas how to stop that from happening?

spiral turtle
#

thx

open bay
#

anyone have any thoughts how we can resolve the kind of rubberbanding happening here? It happens on a rare occasion, player uses a hinge, puck is a few box colliders in a radial array, stick is a collection of box colliders that make a curve.

toxic radish
#

Can anyone help me understand or provide a resource on the logic behind collisions? I've been doing research on Kinematic Controllers and detecting collisions between stuff like walls and the player and it has had me thinking all day haha.

I've seen a bit of Physics.ComputePenetration but i'm not 100% sure if that's a common tactic or not, any input is appreciated!

leaden sapphire
#

is there a way to check for a sweeptest for rotations?
Im trying to make like a basic car controller
for velocity, i check if the object is going to go through an object if moved using this particular velocity using SweepTest
But i want the car to rotate and im not sure how to do that?
Im thinking like a sweeptest to the final position of the all the vertices from their current positions and checking if it collides but i think it wouldnt work fine for large collisions

#

sorry a raycast from all vertices for the rotation part instead of a sweep test

stuck bay
#

im using the famous MouseLook.cs for camera control but i dont want it to go through the terrain and the colliders dont work because its not rigidbody controlled. Any ideas?

halcyon crescent
#

Continuous collision detection is a feature to prevent fast-moving colliders from passing each other. This may happen when using normal (Discrete) collision detection, when an object is one side of a collider in one frame, and already passed the collider in the next frame. To solve this, you can enable continuous collision detection on the rigidbody of the fast-moving object.

inner gazelle
#

Can you set a collider so that it only collides with objects with the tag walls?

floral prism
#

Hi I'm thinking to switch to unity but before I wanted to know if there's a function to move objects in space (with slopes) or do you have to make it yourself with raycast (I'm making a 3D side view game, like mario for example).
If there's such a function does it work well ? are the physics good ?
I'm coming from godot and I can tell you that the physics are completely broken and need several workarounds...

stable shadow
#

Is there a way to calculate a surface world angle that get hit by a raycast ?

viral ginkgo
#

@stable shadow you can get normal of the hit

#

if you want a float out of this, i think you want to do Vector3.Angle(Vector3.up, hit.normal)

stable shadow
viral ginkgo
#

@stable shadow if thats the case that number should be what you are looking for

#

i just dont know if its in degrees or radians

#

but it is the angle of surface hit by raycast no matter which direction you cast the ray

stable shadow
#

nice thnx

pine warren
#

I'm trying to figure out the force to apply to a point on a rigid body, to stop that point from moving. Began with a simple test based on the point being the center of mass. But when trying to do the same thing when the point is off center. Things blow up. I guess I need help on how to adapt the force depending on the leverage gain due to the point not being at the center of mass.

# 
Vector3 stopForce = -Vector3.Project(velocity + Physics.gravity * Time.fixedDeltaTime, -transform.up) * rigidbody.mass

This is how I've done it until now.

#

I tried grabbing the velocity using rigidbody.GetPointVelocity() to get the velocity at the point I want to "stop". But using the same stop force calculation and applying it on the stop-point, results in waay to much force being applied. Causing the rigidbody to spin away out of control.

viral ginkgo
#

@pine warren you can't stop both linear velocity and angular velocity of an object via applying one force to a predefined point?

#

i think there has to be at least three points and three forces for that to be possible

pine warren
#

only want to stop the point, not the whole object.

#

But that might be the same issue I guess.

viral ginkgo
#

if the object rotates, and this point is not the center of mass
you cant stop this points movement?

#

working on spaceship stabilization?

pine warren
#

No, actually a suspension-thing for a car.

#

I want to calculate a "stop force" when the suspension is fully compressed.

#

that prevents the car from rotating further into the ground.

#

At the same time I want it to be generic enough to allow for multiple "wheels" to be attached to the same rigid body.

#

Simplified scenario:

unknown.png
#

black X = center of mass. Green X = points that I want to apply force to, when the green "sticks" become to short.

viral ginkgo
#

this is for preventing extreme suspension cases?

#

isnt that already what your joints are doing?

pine warren
#

Its to prevent the wheel/suspension from sinking into the ground (and letting the black box handle the intersection-problem)

#

The green sticks in my case is currently simple raycasts. If the distance to ground is shorter than the minimum suspension-length, I need to apply a "stop force" that prevents further movement of the green X

viral ginkgo
#

oh wait wait

#

so this would be like "stiffness" of the suspension

#

you just wanna try to stop that points velocity

#

right?

pine warren
#

Yeah

viral ginkgo
#

you should be able to get velocity on point

#

in rigidbody

pine warren
#

Yeah. I'm using that to get the velocity

viral ginkgo
#

and counter it

pine warren
#

Indeed.

viral ginkgo
#

give it a multiplier that feels nice enough

#

and thats not enough?

pine warren
#

Not really. Simply multiplying by arbitrary number will need constant calibration if the "wheel axis" changes...

viral ginkgo
#

I'd choose this method i think
Afterall, all joints always have some sort of paramaters

#

I'd find a nice multiplier and multiply it with the weight that suspension carries when the car is flat on ground

#

With some torque math

#

where the weights sum must equal to cars weight
and torque sums must equal zero

#

That would just be automatically "tuning" the suspensions pretty much

pine warren
#

Yeah, tried a super simple approach. But it doesnt even come close to work:

var velocity = rigidbody.GetPointVelocity(suspension.attachPoint);
rigidbody.AddForceAtPosition(-velocity, suspension.attachPoint, ForceMode.VelocityChange);
#

It sends the whole "car" spinning away like crazy.

viral ginkgo
#

ForceMode.VelocityChange is equilevant to adding to velocity or setting it?

# 
rigidbody.AddForceAtPosition(Vector3.zero, suspension.attachPoint, ForceMode.VelocityChange);

I mean maybe this is what you needed to do

#

But i dont know

#

I'm reading the docs but it doesn't seem very clear to me

#

@pine warren

pine warren
#

using the basic AddForce(), and it will calculate a force that adds/reduces velocity in the given vector.

#

But with AddForceAtPosition, it doesnt seem to work at all. Doesnt seem to take angular momentum etc into account at all.

viral ginkgo
#

hm

#

i think the force it applies is on correct direction but wrong magnitude

pine warren
#

yeah it seem to calculate the force as if applied at center-of-mass. Comparing to my initial apprach, it gives the same result.

#

which is off by a LOT

#

Oh well, need to look up that whole interia tensor, angular velocity etc I guess.

viral ginkgo
#

@distant mango If it moves like 10 meters every fixedupdate, and does a 2 meter radius overlap sphere, it will not cover some area

#

maybe you wanna do spherecasts instead of overlapspheres

viral ginkgo
#

if thats your case, you should use spherecast

#

it basicly sweeps a sphere and gives you the first or all colliders it touches

#

spherecast has a point, radius and a direction

#

@distant mango it looks like you are trying to detect objects in a trajectory some lerping object makes

viral ginkgo
#

yes

#

spherecast is raycast

#

but with spheres

#

Spherecast:
a sphere with this point,radius
move it in this direction for this distance
tell me what it hits

OverlapSphere:
a sphere with this point,radius
tell me what colliders is this colliding with

viral ginkgo
#

@distant mango

unknown.png
#

spherecast is basicly overlapsphere but in a capsule shape

#

because it sweeps a sphere

#

when you sweep a sphere, you get capsule

viral ginkgo
#

@distant mango spherecast will look like a capsule

#

and endpoint will be the next position you are going to have in your coroutine

#

@distant mango if you cant calculate next point, store and use the previous point

#

do it however you like

#

you should get the idea of spherecasting now

viral ginkgo
#

paste the code

# 
private IEnumerator Record_Collisions()
    {
        Vector3 centerOfSphere = ballShoot.visualsRootObject.transform.position;
        float radiusOfSphere = mainTriggerCollider.radius;
        LayerMask layerMask = targetLayerMask;
        float projectileDistance;
        Vector3 projectileDirection;
        RaycastHit hit;
        Collider hitCollider= null;

        while (hitCollider == null && triggerActive)
        {
            projectileDistance = Vector3.Distance(centerOfSphere, ballShoot.visualsRootObject.transform.position);
            projectileDirection = (ballShoot.visualsRootObject.transform.position - centerOfSphere).normalized;
            centerOfSphere = ballShoot.visualsRootObject.transform.position;
            Debug.DrawRay(centerOfSphere, projectileDirection.normalized * projectileDistance, Color.white, 1000); // debug ray
            if (Physics.SphereCast(centerOfSphere, radiusOfSphere, projectileDirection, out hit, projectileDistance, layerMask))
            {
                hitCollider = hit.collider;
                break;
            }
            
            yield return null;
        }

        CollisionDone();
}
#

@distant mango i added a drawray

#

on top of your spherecast

#

try like this and tell me if you see a fully connected line on projectile trajectory

#

then its either your layermask or radius

#

or maybe the object you are trying to detect doesnt have a collider

#

maybe its about the "triggerActive" or something

#

i have no idea

sleek creek
#

Hey, not sure if this is the right area. I use root animation which moves my capsule collider controlled character. However, when it comes in contact with another capsule (my character attacks an enemy with melee) the player capsule will often "slide" up to the top of the enemy capsule. And it is then...floating in the air until the capsule beneath moves.

I don't want to lock Y position because I have a jump mechanic.

I asked some animators/root motion people but they said it was a physics issue. Any ideas how to stop that from happening?

summer fog
#

does physx have a default speed limit of 100 m/s?

shell night
#

no

summer fog
#

wierd

#

I have a rigid body that i'm applying forces to

#

and it just doesn't go more than 100m/s

#

but I'm not doing anything to cause that

#

the code that applies the force is still applying it

edgy aurora
median umbra
#

Trying to implement a simple balancing board with a hingejoint, but as soon as anything touches the board the physics spaz out and it starts spinning like crazy. Feel like I'm missing something simple anyone have an idea? 🙂

#

when my player object hits the board it spazzes out completely. I've locked the X, Y rotations so it can only rotate in the Z axis, but somehow it gains ridiculous amounts of velocity as soon as my player object touches it.

median umbra
viral ginkgo
#

@median umbra you shouldnt need to lock the rotation axices

#

i think you didnt configure the hinge joints axis*

median umbra
#

Let me check 🙂

#

Yep that did the trick haha

#

thank you!

viral ginkgo
#

np

pine warren
#

Unity physics is driving me crazy. Been debugging a issue with my hover-car implementation. Finally did a test vehicle consisting of a single rigidbody with a sphere collider. Which is pushed along my road objects. And for some reason, Unity makes the sphere bounce when moving over edges. For no apparent reason. The edge vertices of the objects both have the exact same world position.

#

(ignore the gray box, its simply moved to the spheres position in its Update-method, its there to make the issue even more apparent)

#

What could cause this issue?

timid dove
#

It's a physics quirk

#

There's a way to mitigate it from physics settings but not totally eliminate it

#

The best way to fix it is find a way to turn your track into a continuous Collider

pine warren
#

You must be kidding me?! A single huge collider sounds like a bad idea for so many reasons.

dreamy pollen
#

There is no way to update Physics for some objects before others, right?

#

It goes
FixedUpdate
PhysicsUpdate (everything updated at once)
and any physics applied at any point past physics update just gets updated next simulation frame (FixedUpdate/PhysicsUpdate)

frail hemlock
#

When I turn on use gravity add rigid body still my cube stays floating in air

#

How to fix this

glacial jolt
frail hemlock
#

No

#

It doesn't even get added forces

#

It's stays in one place

viral ginkgo
#

@dreamy pollen what do you want to archieve by that?

dreamy pollen
#

@viral ginkgo 3d platformer. I am manually managing my player controller's rigidbody velocity. He raycasts the ground to determine if he's standing on ground. As part of the ground sensing, I am having the raycast collect information about the point velocity of the other rigidbody at the location of where the player is standing. This allows me to apply that velocity to the player and having moving platforms. It works very well, as you can see here

#

Issue is, since the environmental velocity for this frame hasn't happened yet, GetPointVelocity is getting last frame's velocity. This can lead to desync issues, especially on rotating surfaces

#

I'm beginning to suspect my only out here to get this perfect is some really convoluted simulating the next frame and rewinding nonsense

viral ginkgo
#

when the physics system adds force on an object, that force is applied to velocity after the end of the simulation step
unless you directly set velocities or fiddle with positions/rotations etc... outcome of the physics simulation should not change even if you managed update objects in a different order

dreamy pollen
#

Yeah, what I really need is a way to simulate the environmental physics first, and the player after that. There's no clean solution that I can see because Unity does all the physics at once

viral ginkgo
#

i was trying to implement something like a handbrake for example, i had a sphere for wheel
after setting wheels angular velocity to zero everyframe, my car would still slip little by little

dreamy pollen
#

I wonder the implications of halving my fixed timestep to double the simulation frame rate, and have some messy system that alternates updating physics each frame,
frame 1 Environment
frame 2 Player
frame 3 Environment
frame 4 Player

viral ginkgo
#

you could set objects kinematic to do that kind of alternating i guess

#

but there might be cleaner solutions

dreamy pollen
#

Hrmm, let me know if you think of something cleaner... it's the best solution I can imagine yet

frail hemlock
#

help

#

its not working

#

when i add a force to the cube

#

it still doesnt follow gravity

#

nor does it follow my forces

#

did i do any mistake

viral ginkgo
#

@dreamy pollen
if you calculate the change in the velocity of the grounding point,
that vector is on the direction your character sways

#

could do a compansation force maybe using that

pine warren
#

@dreamy pollen try taking the moving platforms velocity and add the velocity*fixedTimeStep on top.

#

For rotating bodies you probably need to take the platforms angular velocity into account. Otherwise your character will probably move in the tangent direction.

dreamy pollen
#

It definitely won't be perfect, but it might be a better outcome

#

And I wouldn't need to do anything too crazy like alternating physics frames

wise shell
#

Is there a specific order to the contacts from a collision?

timid dove
#

There's unfortunately no satisfying answer in there

#

even if you dig down into the more recent comments from 2015 :). Damn I've been using Unity for a long time now

distant coyote
#

@dreamy pollen you can run more than 1 physics "scene" at the same time.

summer fog
#

yea

#

that's what I'm doing to support my double precision coordinate world

#

I create physics subscenes

#

and you can just manually call simulate() on them

#

with whatever timestep they are supposed to be simulating

dreamy pollen
#

@summer fog @distant coyote Do you have issues with physics between the two physics scenes not interacting with each other and having to do some jank to make them "see" each other?

distant coyote
#

@dreamy pollen they implicitly dont interact with eachother.

dreamy pollen
#

I was lightly researching that option yesterday

#

that's what I thought :/

summer fog
#

You have to go to great lengths

distant coyote
#

you'd end up having to solve the penetrations and resolve the collisions yourself at that point

summer fog
#

To make things that are near each other

#

End up in the same scene

distant coyote
#

there's an implementation of Bullet for Unity

#

if you really want to do a deep dive

#

you'll get a ton more control

dreamy pollen
#

But I can download Bullet in a test project and play with it

summer fog
#

Derp what's the problem

#

That you want to solve

dreamy pollen
distant coyote
#

any time you have large-ish intertia (angular or linear) and you find your error is a bit high

#

crank the substeps up

#

see if it goes away

#

TL;DR looking at a problem at 50hz can look impossible, but looking at it at 1000hz makes it trivial

dreamy pollen
#

okay but lol

#

the CPU overhead would be massive

#

I'm simulating at 120hz

distant coyote
#

in the case of solving stuff like that rotational disc

#

you can get away with doing real math instead of relying on GetPointVelocity for sure

#

(assuming its rotation is normal and not eccentric)

#

(see the difference between Constant Angular Velocity and Constant Linear Velocity)

queen marlin
#

Hello everyone 🙂 Is there anything that can be done to improve the collision quality of a mesh collider (non-convex)?

#

Main goal being to reduce "fall-throughs"

#

(or eliminate ideally lol)

stuck bay
sullen loom
#

does anybody know how i can apply an explosion force in 2d?

vague cairn
#

@sullen loom Haven't actually coded with unity before, but have done some documentation reading--circle collider where you take distance from center to apply force?

#

if it's a moving object exploding might want to take that into account too

#

but generally haven't seen that much in 2d games--usually just a radius

vague cairn
#

Meanwhile, I was working on an interface for an old, traditionally 2D level format recently in my free time, and discovered someone's been working on a client for the same game for a number of years--wants to use 3D. One thing I'm wondering is there a generally good approach for transforming the tilemap concept into box colliders? I guess also he's having some issues with collisions being indeterminate but don't really know why because I'm unfamiliar with Unity aside from what I've read in the documentation so far--said something about raycasters.

#

Note tilemap format is sparse.

summer fog
#

Instead of discrete

#

Do that on the rigid body it is connected to

#

Anything that can move quickly should probably be set to that

dim kiln
#

is there any way I can add extra camber angle to the wheels using unitys wheel colliders?

lapis tusk
#

I am looking for water physics for vr ( pouring water between cups) I've been looking around but i cant find anything

timid dove
dreamy pollen
distant coyote
#

@dreamy pollen the angular velocity of what?

#

a spinning object that user is standing on? ( based on context of yesterday )

dreamy pollen
#

yes

#

Here's my stab at it, but it seems like it's overshooting somehow (instead of slowly sliding outward off the platform, player starts slowly sliding inward towards the center)

OtherRbVelocity = otherRb.GetPointVelocity(groundHit.point);
OtherAngularRbVelocity = otherRb.angularVelocity;
if (groundHit.transform.tag == "Spinning Platform")
{
    var projectedVelocity = Quaternion.Euler(OtherAngularRbVelocity) * OtherRbVelocity;
    OtherRbVelocity = projectedVelocity;
}
#

the var projectedVelocity line... I have no idea what the mathematical significance of this number is... but it produces a pretty good result:

var projectedVelocity = Quaternion.Euler(OtherAngularRbVelocity * 0.239f) * OtherRbVelocity;

maybe it just happens to produce a good result, not because it is remotely "correct".

icy frigate
#

Hey guys! I have a simple question, if I am making a 2d rap with a top view, should I code my own character controller and check every collision with a overlapAll or should I instead use rigidbodies. (I don't really like rigidbodies because I fell like they are more gonna a pain in the ass on the long run. On the other hand, I want to be able to use OnTriggerEnter and things like that because they are quite useful and I hate the fact that every tick, I check all colliders inside a radius)

timid dove
#

However if you want the character to slowly slide off then use that same formula, but scale down the force by a bit. E.g. multiply by .98 or so

#

(make sure your spinning disc has no friction of course, or it will throw things off)

dreamy pollen
#

There are no rigidbody physics at factor here, as my controller is a floating sphere above the platform in question and I am manually managing his velocities

#

it has to do with the fact that I'm raycasting down from the player and using GetPointVelocity to get the velocity and angular velocity of the point he's floating above

#

GetPointVelocity gets information from the last physics update, since Unity calculates all its physics at once.

#

this has the effect of always being outdated velocity information and pushes the player outward in a way that looks exactly like centrifugal force

#

@timid dove

timid dove
dreamy pollen
timid dove
#

adding force is the same as changing velocity

#

you can use just the overall angular velocity of the disc and the distance you are from its center

dreamy pollen
#

I'll do some more research, thanks for sharing

tender trellis
#

i have been researching and trying for the last few days now. and i still couldn't find a solution.

How can i keep 2 or more different force sources work independent from eachother,

as Example, I want the character move ( preferably using force/velocity ), and be able to be pushed or pulled around external forces such as gravity, world events, abilities and explosions.

adding external forces with only add force, works OK. But my game is an RTS type, and i need moveToPosition type of movement mechanic, and i can't move the character at constant speed without affecting the velocity of the external forces.

I need help, advice, suggestions, anything at this point.

PS: I have been trying to move the character with transform, and apply force to it. But when both combines, it creates networking issues.

kind kettle
#

The only way out I can see is too basically zero out the external forces and take it from there

ruby pelican
#

Hey all! Pretty sure that this channel would be the best-fit for the question I have, but I've been researching the SkinWidth property of the built-in character controller and I'm trying to understand the benefit of using skinWidth instead of just increasing the radius of the collider. Are there any skinWidth experts around? 🙂

dreamy pollen
#

Looks like it just allows colliders to slightly penetrate one another

ruby pelican
#

Yeah, thank you 🙂 Was looking for a little more than what's shown there. Was searching through the github to see if I could see how it actually works

dreamy pollen
#

I personally quickly abandoned the character controller for my game because I found it too simplistic, I am much more satisfied with what can be accomplished with rigidbodies

#

(also there were some unsolvable problems using character controller)

ruby pelican
#

Totally agree -- I'm making a video on my channel explaining how to use the built-in. The more I use it, the more I realize the video is going to need an asterisk at the start stating that this really can only be used with games that don't require much mobility (like a jrpg or something)

dreamy pollen
#

right, I'd agree that's a fine fit for it. Great for beginners to get started with too.

ruby pelican
#

For sure 🙂 SimpleMove appears to be the simplest way to get the character moving without much work

dreamy pollen
#

If I wanted to store a collision between 2 rigidbodies OnCollisionEnter and apply the results of that collision at a later time, how would that work?

glacial jolt
dreamy pollen
#

@glacial jolt Yup, I've got that stored, what is the appropriate way to add the collision data to the collided objects such that the velocities are "resimulated", I guess for lack of better word

glacial jolt
#

hmm, it depends what you're going for. Collision.impulse will store the actual impulse applied to separate collision pairs, so that's probably the closest to what you'd want

dreamy pollen
#

What I'm attempting is somewhat ludicrous, but I'm trying to split my Physics simulation in half by dividing FixedUpdate into two managed Update functions, FixedTick and FixedTock

#

Here with a really slow timestep

#

The issue comes in mostly with collisions being "missed" due to the physics simulation being cut in half, and the only thing I get is what I think is called "depenetration"?

#

The cube is running in Tick, the Capsule in Tock.
The pink spheres in Tick, cyan spheres in Tock

#

You can see that the cyan sphere does not produce the correct result when hitting the green cube, as I am attempting to get them to simulate in different physics timesteps

#

I just want to capture that collision data (in Tick) and queue it up to be executed in Tock

#

@glacial jolt Hopefully what I'm trying to do makes sense... imagine two alternating 60 tick simulations happening in 120 tick fixed timestep

glacial jolt
#

what responsibilities do Tick and Tock have each? Not super clear on the use case

#

like, do half the objects get simmed in one and the other half in the other?

dreamy pollen
#

Right, that's the idea

glacial jolt
dreamy pollen
#

They do interact

#

The end result intent is just to allow me to simulate some of the physics objects in the world before others, as Unity doesn't really let you do this by default with the FixedUpdate workflow

#

Some of the things that I want to do in Tock rely on stuff from Tick having happened First to work correctly

glacial jolt
#

ahh. So I'm guessing you want to step all the objects in Tick, for any Tick<>Tick collision pairs play them out as normal, but for Tick<>Tock pairs delay the result of the impulse added to the Tock object until the end of FixedTock?

dreamy pollen
#

Yes, you have perfectly understood 😄

glacial jolt
#

so yea, Collision.impulse should work, by adding that vector as a force at a later time. You'll need to I guess cache the state of the affected Tock object before any collisions are calculated and restore them after, since you can't stop PhysX from immediately applying the results

dreamy pollen
#

Thank you for your help!

unkempt summit
#

Here's a problem for anyone that knows unity physics extremely well. My netcode requires me to, every 20ms, have the client receive a list of all entities and move them back to a certain position and apply velocity, etc.

One thing I have to do this to, are cars, which run on wheel colliders. The problem with this, is that whenever you set the car's rigidbody's position, the wheel thinks its moving, so the wheel just spins infinitely while the car is in place and not moving.

#

Does anyone have any suggestions for getting around this?

#

I've tried setting the brake torque to infinite while the car is getting re-positioned, and then unsetting the brakes after it's finished

#

but that didn't do anything at all

#

I've even tried making the rigidbody kinematic while re-positioning, still nothing

edgy aurora
#

im using configurable joints to enforce the tpose and moving the ragdoll by setting a velocity to the root to reach a target position

#

which i am controlling

viral ginkgo
#

@edgy aurora when you wanna move the body, distribute the whole force onto whole mass

#

each limb will be applied addforce

#

proportional to their masses

edgy aurora
#

thanks i finally got it to work

west geyser
#

I have a pre-build fps character it doesn't have any collider but it do have a mesh and the floor has collider so when I run the game character falls half way through it, it start colliding from the hip but legs doesn't collide

waxen edge
#

I have a small question, what would be the best way to perform a ground check on a Rigidbody?

Check if velocity.y has been 0 for some time?
Check for collisions with raycasts/spherecasts?
Set a bool in OnCollision/OnCollisionExit?

I know it may depend on the project, but I'd like to get some pro/cons for the different methods

west geyser
graceful meadow
# waxen edge I have a small question, what would be the best way to perform a ground check on...

in order of ascending personal preference:

checking if velocity has been zero for some time

  • can't jump immediately after landing
  • can't jump while moving on slopes
  • involves a float equality comparison
  • probably a buggy mess

raycasts or collider casts
+- introduces techs where perfect inputs let you jump before hitting ground e.g. celeste spike jumps

  • uses a layermask instead of the collision matrix, meaning higher maintenance costs and more painful debugging
  • can be unreliable if the ground is bumpy

foot collider + collision messages

  • behaves exactly like you'd want it to
  • requires a more complicated gameobject structure involving multiple scripts and colliders
summer fog
#

I think foot collider is probably just a generally more stable + easier route overall

#

if you count trying to debug everything

graceful meadow
#

mm, for sure

#

the matrix behaves a lot more predictably than layermasks

#
  • collision matrix
waxen edge
#

Thanks for the detailed answer!
I tried the velocity.y == 0f approach as a placeholder, and while I expected it to be buggy as hell, it works perfectly like a charm, I am rlly surprised! My "character" is only a cube atm, so it may not work for complex meshes

#

I don't even check for KeyDown, I check for Key, and there have been 0 issues so far, works like every other ground check I did before, with a way easier setup

fossil oasis
#

I'm trying to make the car fly up in the air when it enters the trigger but nothing happens

#

what am I doing wrong?

coarse sundial
#

this might sound like a stupid question but how do you add physics like gravity

river tide
#

Edit -> Project Settings -> Physics to adjust the gravity in your game

coarse sundial
#

ok

river tide
#

Object has to have rigid body and a collider afaik

coarse sundial
#

ok

river tide
#

If the object is set as Is Trigger I don't think physics is enabled for it

timid dove
#

Collider being trigger or not doesn't matter for gravity. You just need a Rigidbody

slim olive
#

If I want to make a physics explosion at a certain point in the world what method do I use?
where all physics2d objects get moved away from the point
do I do a circlecast and then add an explosion force to all rigidbodies?

little egret
#

wantedRotation = Quaternion.LookRotation(this.transform.up - Vector3.up);
transform.rotation = Quaternion.Slerp(transform.rotation, wantedRotation, rotationSpeed * Time.deltaTime);
Im trying to "selfbalance" an object, if it starting to flip, i want to turn it to point it's up to world up, somehow this isn't working correct, it changes the direction sometimes
anyone has an better solution or fix? Lowering the center of mass is somehow not working correct, i think because im not on the ground.

copper obsidian
#

We are using a rigidbody2d thats kinematic so we can do our own gravity and stuff, our trigger is completely inconsistent. I tried messing with the fixed step, but that would only if you using dynamic and moving things in the fixed update right?

timid dove
copper obsidian
#

If we have a 2d sprite object with its pivot set to the bottom center, is there a way to still rotate the the object based on a center pivot using offsets?

#

The pivot being at the bottom helps with the spline following code we doing

distant coyote
mighty sluice
#

There's a bug with configurable joints: the "edit angular limits" gizmo should appear at the anchor point of the joint (defined by a localPosition relative to the joint's parent), but instead it appears relative to the connected body object

#

only seems to happen when the joint is created at runtime though

#

not sure if it is linked to any other issues but it's possible that the incorrect force points are being used in some cases

unkempt summit
#

Say you have 200 rigidbodies in a scene. If those 200 rigidbodies are moving, is it going to be more CPU intensive than if they weren't moving?

daring ridge
#

@unkempt summit Look into the Sleeping mode. From the documentation: Sleeping Mode: Define how the GameObject “sleeps” to save processor time when it is at rest.

#

Want me to DM you the link?

unkempt summit
#

I think I know what that is

#

just wanted to know how much CPU its going to save

#

Don't rigidbodies automatically sleep when not being fucked with?

daring ridge
#

Well, my educated guess is that it will skip the fixed update for the rigid body, so if it's only a rigid body, it will save a lot, but if you have a lot of custom behavior or other classes attached to it, it will not be as significant.

unkempt summit
#

alright

daring ridge
#

But to answer you other question, a non-official source says: When Rigidbodies fall to rest - a box landing on the floor - they will start sleeping. Sleeping is an optimization which allows the Physics Engine to stop processing those rigidbodies. This way you can have huge amounts of rigidbodies in your scene as long as you make sure that they normally don't move.

keen spoke
#

uhh

#

something is wrong

#

my enemies have triggers that detect the player

#

they are all set to istrigger and have a layer that only interacts with the player

#

now I have on the player a trigger at the feet that collides with ground and stuff

#

but it still registers the enemy trigger colliders and adds them

#

which results in super weird behaviour

#

I can float in the air whenever I'm in one of the enemies range

#

Here is my ground detection collider

#

and here is the player detetion trigger on the enemy

#

both are set to istrigger

#

what's wrong?

#

I thought triggers don't interact with other triggers

hollow echo
#

They won't physically interact with each other though - triggers don't cause physical collisions

keen spoke
#

oh, that's new to me

#

I thought they just didn't trigger each other at all

daring ridge
#

A way would be to have a custom filter in your OnPlayerEnterRange (or ther other one) that skips undesired hits

keen spoke
#

yeah, then no problem

daring ridge
#

I think you can have your trigger collidables all in a certain layer, and make them not interact with that layer

hollow echo
#

Or manage the layer based collision settings to filter them out if possible

keen spoke
#

I think I can just check

unknown.png
hollow echo
#

Or that 🙂

daring ridge
#

You can, but filtering with the layer would probably be more efficient. I'm not talking about significant difference here, though it really depends on your use case.

little egret
#

@timid dove i know it can cause issues it's just for the example, using torque makes it even more complicated, but if i know whats wrong and the wantedRotation is right, i can start using torque to reach the wanted rotation

#

@distant coyote i think i take that into account, i set the origin in start with rb.centerOfMass += new Vector3(0, -anynumber, 0);

twin wolf
#

hey Guys, i have a weird problem and not sure if its from the unity version or some kind of other problem

i'm going through Udemy tutorial with Unity 2019 version and there we have a basic code like this:

public class CheckpointController : MonoBehaviour
{
    public string cpName;

    // Start is called before the first frame update
    void Start()
    {
        if(PlayerPrefs.HasKey(SceneManager.GetActiveScene().name + "_cp"))
        {
            if(PlayerPrefs.GetString(SceneManager.GetActiveScene().name + "_cp") == cpName)
            {
                PlayerController.instance.transform.position = transform.position;
            }
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        if(other.gameObject.tag == "Player")
        {
            Debug.Log("hit cp" + cpName);
            PlayerPrefs.SetString(SceneManager.GetActiveScene().name + "_cp", cpName);
        }
    }
}
#

and the idea is when player dies to respawn(reload scene) on last colided checkpoint (simple 3d box)

#

but im currently with Unity 2020.2 and this is buggy and it spawns me at center of the map and sometimes on the given checkpoints

#

i found about Physics.SyncTransforms(); and when added it after PlayerController.instance.transform.position = transform.position; its working normally...
is this the new way of working with player setting position?

#

this is how scene looks and each checkpoint have unique name

unknown.png
#

anyone have any ideas?

twilit kettle
# 
{
    public CharacterController controller;
    public Transform cam;

    public float speed = 6f;
    public float gravity = -9.81f;

    public Transform groundCheck;
    public float groundDistance = 0.4f;
    public LayerMask groundMask;

    Vector3 velocity;
    bool isGrounded;

    public float turnSmoothTime = 0.1f;
    float turnSmoothVelocity;

    // Update is called once per frame
    void Update()
    {
        isGrounded = Physics.CheckSphere(groundCheck.position, groundDistance, groundMask);

        if (isGrounded && velocity.y < 0)
        {
            velocity.y = -2f;
        }

        float horizontal = Input.GetAxisRaw("Horizontal");
        float vertical = Input.GetAxisRaw("Vertical");
        Vector3 direction = new Vector3(horizontal, 0f, vertical).normalized;

        if (direction.magnitude >= 0.1f)
        {
            float targetAngle = Mathf.Atan2(direction.x, direction.z) * Mathf.Rad2Deg + cam.eulerAngles.y;
            float angle = Mathf.SmoothDampAngle(transform.eulerAngles.y, targetAngle, ref turnSmoothVelocity, turnSmoothTime);
            transform.rotation = Quaternion.Euler(0f, angle, 0f);

            Vector3 moveDir = Quaternion.Euler(0f, targetAngle, 0f) * Vector3.forward;
            controller.Move(moveDir.normalized * speed * Time.deltaTime);

            velocity.y += gravity * Time.deltaTime;

            controller.Move(velocity * Time.deltaTime);
        }
    }
}```
#

im trying to make gravity but when i fall i stop moving if im not moving forward. so pretty much if im

#

not moving my character freezes and floats in the air

viral ginkgo
#

@twilit kettle looks like you arent doing any gravity where you should have, when these conditions are satisfied:

not grounded
&
velocity.y > 0
&
no WASD buttons pressed

#

so you jump, hands off keyboard and you character floats in the air as i see it

#

and if you try to move via WASD, it will fall down again

#

.
either way, you should be doing this: velocity.y += gravity * Time.deltaTime; anyways regardless of what player does

#

and also velocity.y = 0; when grounded

#

i dont know what will character controller do if you tried to make it move into the ground too hard

fresh bane
#

how can i improve this?

swing2.gif
#

i'm using rigidbody 2d, capsule collider 2d and hinge joint 2d

#

this seems to be the max height too

unknown.png
supple sparrow
#

Looking good to me

#

👍

tacit surge
#

Hello, where should I start if I want to code a custom 3D pendulum effect (like a character swinging a rigid rope) without using the configurable joint, if its even possible? When I look online, most of the thing I find use some type of Unity joint, and I feel like its either not what I am looking for (spring joint) or overkill and super complex to set-up ( configurable joint) . Is there an algorithm out there that could be my solution?

daring ridge
#

@fresh bane You asked that forever ago, but I would just tweak the inertia to have it come to rest faster.

timid dove
alpine ingot
heady kraken
#

Hello, I am trying to lift the Tire/Wheel using the bucket of the excavator. I have tried adding Rigid body and colliders but no luck so far... Any suggestions on how this can be achieved?

unknown.png
winter sun
unkempt summit
#

@heady kraken That's going to be extremely weird and wonky with physics alone

#

not to mention, you're going to want a bucket that scoops upwards

#

not downwards

heady kraken
#

@unkempt summit I can control the bucket movement.. Any alternate solutions to make this work?? Attaching the reference to what I am trying to achieve

unknown.png
unkempt summit
#

@heady kraken You will need a detailed circular collider for your rigidbody

#

with a hole in the middle.

#

for the tire

heady kraken
#

Oh okay... Circular collider as in Mesh collider? @unkempt summit

unkempt summit
#

I'm not sure, I've never really used mesh colliders

#

You'll just need to find a way to put a hole in the middle of the tire

#

as a collider

#

so that the crane is able to grab it on the inside

heady kraken
#

@unkempt summit Yup that is exactly what I am trying to do... But not found a way yet... Thanks for the suggestion!

unkempt summit
#

mesh collider will probably work, but they're very resource intensive

heady kraken
#

Another problem with mesh collider is that it has to be convex if a rigid body is used... And convex does not work for hollow Gameobjects (That have a hole)

royal walrus
#

Does anyone know how I can implement an aerodynamics system like Kerbal Space Program?

fresh bane
outer ocean
#

might work decently

#

concave colliders wont work with rigidbodies

modest zodiac
#

Guys this answer has been on Quora for 2 years, it has nearly 3k views and 3 up votes, but is it correct. Are those equations correct?

Distance=Speed/Time 
Speed=Distance∗Time 
Time=Speed/Distance

Shouldn't it be:

distance = speed * time
time = distance / speed
speed = distance / time

?
https://www.quora.com/What-is-the-product-of-velocity-and-time

spiral comet
#

if I jump into the wall and hold W it sticks to the wall how can I fix that?

daring ridge
#

@modest zodiac That looks like a troll answer to me. Yes, your equations are the right ones. To figure it out for yourself, use units.

#

For example: What's a units of Distance, Speed and Time? (an example)
Distance: m
Speed: m/s
Time: s

#

So if you use their distance formula, you'd end up with distance being in m/s² instead of m.

modest zodiac
quasi chasm
#

Can anyone help me with some simple physics
How would you rotate a rigidbody through code?
Add Torque rotates it endlessly
MoveRotation gives me errors about quaternion not being in a correct unity
and angularVelocity is the same as AddTorque

halcyon prairie
#

I'm having trouble with Colliders

#

OnTriggerStay doesn't seem to function

#

correctly

last narwhal
#

Anyone have a good free interactive water asset you can recommend?

frigid pier
#

@last narwhal Don't cross-post. And this has nothing to do with physics.

last narwhal
#

Cross posted on general because I didn't know where this question falls. Has to do with physics because I want the water to MOVE based on colliders and forces. Thnx for mod-ing @frigid pier

frigid pier
#

@last narwhal Still has nothing to do with physics system. You'll need to fake it, preferably with shaders. Next time you'll get a warning for cross-post.

last narwhal
quasi chasm
eager oar
#

hello there. I need help with collisions. I need my collider to collide with something, but not to transfer its force to the colliding object (when a bullet hits you, you don't fly 200 metes away) how can I achieve it?

lavish rose
#

howdy! Have a really newbie question...
I have a seat object and a character animated on it. Now im rb.AddForce-ing the seat hoping the guy the guy would move too (as he is "sitting" on the chair the force is being applied to...) But.... The force makes the seat float through the guy, leaving him in place... I feel like there is some parenting to be done... But how? Seat to the guy? Guy to the seat? Both to EmptyGameObject?

lavish rose
eager oar
#

I am not using one