How to disable the Tracked Pose Driver in a Unity VR Application? - unity3d

I need to write a VR application that disables HMD positional tracking for a specific situation and then reenable it again.
In the UI it is a simple as ticking and unticking the TrackedPoseDriver shown in the picture below.
How can I do that via Scripting?
I assume I need to use the enabled property of a game object. But I don't know how to grab a hold of this GameObject (or Component).
EDIT: In case this was clear this is GameObject/Component associated to the main camera.

Ok. So I was able to do It.
What I did is I search MonoBehaviour Based Components on the camera and then cast it to a MonoBehaviour once I found the right one. And then used the enabled property. Like this:
Component[] components = Camera.main.GetComponents(typeof(MonoBehaviour));
bool found = false;
foreach(Component component in components) {
string name = component.ToString();
MonoBehaviour mb = (MonoBehaviour) component;
if (name.Contains(TRACK_POSE_DRIVER_NAME)){
mbTrackingPose = mb;
found = true;
break;
}
}
The unique string that the toString() method provided was somethign like (I don't have it on hand) "Main Camera (Unity.XR.TrackedPoseDriver)". So I just made sure that the string had the "TrackedPoseDriver" and stored that as a MonoBehaviour.
I hope this helps someone else.

Related

Check if a gameobject is visble on the current camera

I've been searching stack overflow and the internet for a bit trying to search for a solution to this issue, everytime i try to use OnBecameVisible() or OnBecameInvisible() or TestPlanesAABB to check if the object is not visible through the wall, the camera can still see the object through a solid wall.
Video of the problem here:
https://youtu.be/3HiEugm6On8
As you can see, if i'm looking at him he stops moving, if i turn around and he "unloads" or "becomes invisible" he moves closer, but if i go around a corner still looking in his direction he stops moving as if i can see him and there is no wall there, this is what i'm looking to solve
it's an enemy that roams around, and i want him to only move if i cannot see him, which i thought would be fairly simple, but alas it seems not to be as simple as i thought
my current code is basic:
public bool IsSeen = false;
public void OnBecameVisible()
{
Debug.Log("I can now see you");
IsSeen = true;
}
public void OnBecameInvisible()
{
Debug.Log("I can't see you");
IsSeen = false;
}
this is attatched to the object that i wish to detect / not detect through walls, which i do believe checks if the object is viewable by the camera that i choose.
does anyone have any ideas as to how i can fix / achieve this?
As already mentioned the general "problem" with Renderer.OnBecameVisible is
Note that object is considered visible when it needs to be rendered in the Scene. It might not be actually visible by any camera, but still need to be rendered for shadows for example. Also, when running in the editor, the Scene view cameras will also cause this function to be called.
So its not really usable for you.
is there a simple way to raycast the whole screen?
Unfortunately not really :/
You can a bit avoid this using GeometryUtility.CalculateFrustumPlanes in order to get the four planes of the camera frustrum. Then you can check whether the object is actually inside the frustrum using GeometryUtility.TestPlanesAABB
var cam = Camera.main;
var planes = GeometryUtility.CalculateFrustumPlanes(cam);
var objCollider = GetComponent<Collider>();
if (GeometryUtility.TestPlanesAABB(planes, objCollider.bounds))
{
Debug.Log("I am inside the camera frustrum!");
}
else
{
Debug.Log("I am out of sight...");
}
However, this still does not cover any other object being in front of the target object and therefore actually covering it.
You would need to define exactly what visible means (e.g. any portion of the mesh? Is the center of the object enough to test? etc).
For e.g. testing only the center of the object you could use a Physics.Linecast like e.g.
if (GeometryUtility.TestPlanesAABB(planes, objCollider.bounds))
{
Debug.Log("I am inside the camera frustrum!");
if(Physics.LineCast(cam.transform.position, objCollider.GetComponentInChildren<Renderer>().bounds.center, out var hit)
{
if(hit.gameObject != objCollider.gameObject)
{
Debug.Log("..but something else is in the way..");
}
else
{
Debug.Log("Now you see me, muhaha!");
}
}
}
If you want it to be more precise and track of any part of the mesh is visible then it actually gets tricky. You would need to raycast multiple key points of the bounding box (e.g. each corner, centers of the edges etc) depending on your needs.

How do you fire off the Cinemachine Impulse source without using the Collision one?

How do properly call GenerateImpulse() to implement Cinemachine's camera ImpulseListener (camera shake) via the ImpulseSource? I can get it working if I put a CollisionImpuleSource on the player, but I don't want that. I want to use the Impulse Source and then with code, determine when to shake.
I'm looking at the documentation https://docs.unity3d.com/Packages/com.unity.cinemachine#2.3/manual/CinemachineImpulseSource.html but not seeing how to properly make the ImpulseSource fire off.
I set a private...
public CinemachineVirtualCamera vCamera;
private CinemachineImpulseSource _impulseSource;
I can call the generateImpulse...
_impulseSource.GenerateImpulse();
but I don't see how to get the component
private void Start(){
_impulseSource = vCamera.GetCinemachineComponent<CinemachineImpulseSource>();
}
I get an error..
The type
'Cinemachine.CinemachineImpulseSource'
must be convertible to
'Cinemachine.CinemachineComponentBase'
in order to use it as parameter 'T' in
the generic method 'T
Cinemachine.CinemachineVirtualCamera.GetCinemachineComponent()'
but if I change the private too..
private CinemachineComponentBase _impulseSource;
that doesn't help. Need some guidance on how this should be referenced.
Think of the CinemachineImpulseSource as a component on a custom GameObject.
Attach the CinemachineImpulseSource Script Component to a new gameobject. You could probably add it to the same GO where the script from your question is attached to, did not test this though.
Configure the impulse source component according to your needs and reference it. If its on the same GameObject, create a public field just as with your camera reference and assign it in the inspector or get it using GetComponent<CinemachineImpulseSource>(). Then you can call GenerateImpulse() on it.
public CinemachineVirtualCamera vCamera;
public CinemachineImpulseSource ImpulseSource; // Assign in inspector
...
ImpulseSource.GenerateImpulse();

Best practice to to access components using scripts in Unity?

I am new to Unity so go easy on me. :)
I added an game object with a text field component (via TextMeshProUGUI) to my heads up display in my scene. I want to use this to display various statistics on it for debugging purposes during game play.
I then created a script which I added as a component to the same game object that holds my text component. Is this the best practice? Not sure how else I would get the script to execute.
Once I had my script created, I needed to find the text component as well as some other components in my scene so I could display the debug information. Below you can see how I did it... it feels a little dirty to be searching the entire scene to find these things. Would love some insight on how long-time Unity programmers go about this!
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using TMPro;
public class PlayerDebugStatistics:MonoBehaviour {
TextMeshProUGUI playerDebugStatisticsText;
PlayerCharacterController playerCharacterController;
Health playerHealth;
private void Start() {
// First find the object in the scene named "PlayerDebugStatisticsText" and then get it's TextMeshProUGUI component
this.playerDebugStatisticsText = GameObject.Find("PlayerDebugStatisticsText").GetComponent<TextMeshProUGUI>();
// Get the player character controller
this.playerCharacterController = GameObject.FindObjectOfType<PlayerCharacterController>();
// Get the player health from the player character controller
this.playerHealth = playerCharacterController.GetComponent<Health>();
}
void Update() {
// Update the text every frame
this.playerDebugStatisticsText.SetText(string.Format("{0:N2}", this.playerHealth.currentHealth));
}
}
3 ways
Create an inspector reference to the other object and access it from your script - a public or private (with [SerializeField]) attribute in your script - and drag the component in like in this video: https://youtu.be/dMgQOP7kdxg?t=425
Use the singleton pattern: https://www.youtube.com/watch?v=5p2JlI7PV1w
Use dependency injection - https://github.com/modesttree/Zenject
Your way isn't terrible if you don't do it in the Update() loop, and cache your objects (like it appears you are doing), but if you need that performance in Start(), the above options can help.

Unity3D Text not changing after being set in Start()

I have a Canvas (World Space Render mode) with a Text and a Button component displayed in a tridimensional space (it's a VR app). The canvas instantiated at runtime using a prefab.
I get a reference to the Text object using:
_codeTextLabel = canvasPrefab.transform.Find("CodeTextLabel").gameObject.GetComponent<Text>();
I want to update the text at run-time using:
void Update()
{
_codeTextLabel.text = _codeText;
}
where _codeText is just a variable I update based on specific events.
The problem is that the Text gets updated only the first time, but if I try to change the variable nothing happens. I have tried several combinations and also the method _codeTextLabel.SetAllDirty() but it doesn't work.
The only way to update the text is to re-instantiate the prefab.
Are you instantiating your prefab before setting the values. If you are storing the _codeTextLabel reference before instantiating then your reference will point to the prefab not the runtime object. I can't see the rest of your code, so I can't say for sure. (I would have asked as a comment, but as I'm new I don't have the reputation to do so)
edit: I did a test to try and recreate your problem. I made the following script and it appears to work as expected. CanvasPrefab is a worldspace canvas with a UnityEngine.UI.Text component attached. (The script is attached on an empty game object in the scene btw)
public class ChangeText : MonoBehaviour
{
public GameObject CanvasPrefab;
private GameObject runtimeCanvas;
public string runtimeText = "something";
private Text textRef;
// Start is called before the first frame update
void Start()
{
runtimeCanvas = GameObject.Instantiate(CanvasPrefab);
textRef = runtimeCanvas.GetComponentInChildren<Text>();
}
// Update is called once per frame
void Update()
{
textRef.text = runtimeText;
}
}
as long as you did something wrong, It works absolutely so I guess there are several cases
Failed to do "_codeTextLabel = canvasPrefab.transform.Find("CodeTextLabel").gameObject.GetComponent();"
'_codeTextLabel' lost reference from 'GameObject.
Doesn't change runtimeText' change at all
Subscription of events failed I mean, your updating scripts doesn't get proper event to update that text.
Without codes, this is only thing I can guess for yours so please check above I hope there is case among above.

Add particles on button click in unity

I am new to unity 3d, I have to do some enhancement in exiting project.. if user choose correct option then I have to show some particles around the button at runtime.
My code for adding particles is below ..not working:
ParticleSystem ps = GetComponent<ParticleSystem>();
ps.Play ();
I have also added particles component from unity editor..
Thanks in advance
Edit :
as #kardux suggested:
declaration :
[SerializeField] private ParticleSystem ps;
on method :
ps.Play()
Screenshot from inspector:
Error:
I/Unity (23313): NullReferenceException
I/Unity (23313): at UnityEngine.ParticleSystem.<Play>m__0 (UnityEngine.ParticleSystem ps) [0x00001] in /Users/builduser/buildslave/unity/build/artifacts/generated/common/modules/ParticleSystem/ParticleSystemBindings.gen.cs:3666
I/Unity (23313): at UnityEngine.ParticleSystem.IterateParticleSystems (Boolean recurse, UnityEngine.IteratorDelegate func) [0x00003] in /Users/builduser/buildslave/unity/build/artifacts/generated/common/modules/ParticleSystem/ParticleSystemBindings.gen.cs:3780
I/Unity (23313): at UnityEngine.ParticleSystem.Play (Boolean withChildren) [0x00020] in /Users/builduser/buildslave/unity/build/artifacts/generated/common/modules/ParticleSystem/ParticleSystemBindings.gen.cs:3666
I/Unity (23313): at UnityEngine.ParticleSystem.Play () [0x00005] in /Users/builduser/buildslave/unity/build/artifacts/generated/common/modules/ParticleSystem/ParticleSystemBindings.gen.cs:3661
First of all if you're using particles inside Unity UI I highly advise you looking to UIParticleSystem.cs script from Unity UI Extension repository: this is a community gathering of many useful UI tools :)
(simply don't forget to add the UI/Particles/Hidden shader that you can find here)
You can change the sprite you want to use here:
Also keep in mind when using this script that you will have to scale your particles according to your screen (particles are initialized at a size of 1 because that's 1 meter in Unity 3D world: but now you will probably be in canvas space which will be something like 1920x1080px so 1px will be very small). You can find some base settings below:
Now coming to your scrip I suspect you simply have to call Stop() before Play() like this (note I used a burst emission type in my particle system settings):
ParticleSystem ps = GetComponent<ParticleSystem>();
ps.Stop ();
ps.Play ();
P.-S. Please note that if you use UIParticleSystem script you will have to consider your particles system as an UI item (will be rendered on top of other items based on hierarchy order)
Hope this helps,
EDIT:
You have two ways of setting up your GameObjects:
you have all component on the same GameObject (ParticleSystem, UIParticleSystem and YOUR_SCRIPT): this way you can get the ParticleSystem reference by calling GetComponent<ParticleSystem>() inside your script
you have one particle GameObject (with ParticleSystem and UIParticleSystem) and YOUR_SCRIPT is on another GameObject: you can't call GetComponent<ParticleSystem>() in your script since it will search on the components of this GameObject so you declare a ParticleSystem ps; variable (either public or [SerializeField] private) that you assign through the Inspector by dragging your particle GameObject to it.
Note that implicitly, GetComponent<ParticleSystem>() equals this.gameObject.GetComponent<ParticleSystem>(): that's why it will search components from the current GameObject.
EDIT 2:
Not sure why your script throw this NullReference exception: I just tried with a very short script and it works perfectly...
public class TestScript: MonoBehaviour
{
[SerializeField]
private ParticleSystem ps;
void Start()
{
// This one is not even needed
ps.Stop();
}
public void PlayParticles()
{
ps.Stop();
ps.Play();
}
}
Provided you have a particle system on the same gameObject as the script that is calling it, it should be fine.
Are you using a UI button? If so, have a look here..
http://answers.unity3d.com/questions/852397/particle-system-in-46-ui.html
It's old but still relevant.
Are you using the New Unity UI System or GUI, Is the UI worldspace?
Create a empty gameobject - attach the particle to that.
Whenever you want emit particles call Gameobject.SetActive(true);
Make sure Play on Awake option is checked in the particle system.
Set the position of the particle according to your UI.
public GameObject particle;
//include the particle in the gameobject
void Start() {
particle.SetActive(false);
}
void button() {
particle.SetActive(true);
}
//this works.