I'm developing a game using Box2D. I have to move ball according to accelerometer. I have created a body n connected ballsprite to it. I'm moving body using setLinearVelocity(). once the ball reaches the boundaries of screen,i want to stop the movement of ball at the edge of the screen. How do i do this?
public void onAccelerationChanged(AccelerationData arg0) {
ballBody.setLinearVelocity(arg0.getX(), 0);
}
you can set the body velocity to zero when reach the boundaries.Place the condition in update handler and then place below statement
body.setLinearVelocity(0, 0);
(or) you can make the the body type to static
body.setType(BodyType.Static);
Related
enter image description here I am instantiating prefabs and listing them on a scroll list. I am trying to teleport the player to instantiated prefab position when I click its reference on scroll list listing?
All suggestions are welcome.
From what I understand about your problem (explained in the comments rather than the question), you should be able to do this:
You can instantaneously move an object camera by setting its transform's position to the instantiated prefab's position when the click has occurred. For a camera, you probably have the camera view in X and Y dimension, so you want to move it to the new X and Y position but leave the Z-position as it is.
One potential solution: Add the following script to the GameObject with your Button component. Then add an event-listener on the Button component that points to the newly added script component and choose the MyTeleportingButton.OnClick as the target method. You also need to drag in the camera as a reference in the new script component.
public class MyTeleportingButton : MonoBehaviour
{
public GameObject camera;
public void OnClick()
{
// casting to Vector2 in order to move in 2D only
var currentPosition = camera.transform.position;
var newPosition = transform.position;
// set same depth as camera
newPosition.z = currentPosition.z;
camera.transform.position = newPosition;
}
}
Im having problems with position convertions. The way im trying to solve it may be very wrong but thats due to inexperience in that case and im up for any suggestion on how to do it differently.
What im trying to do is a gui with a dot graph envelope that the user can change by draging the dots with the mouse.
This is what i would wan it to look like.
https://imgur.com/FP6f1Cz
First i did the UI like normal in overlay but i couldnt get the line renderer to work so i took the whole ui into world space. This makes the line renderer visible. With the UI in world space ive tried both to put the envelope line renderer in the canvas with the rest of the ui and outside the canvas UI.
Here is the code that renders the lines where the dots are and moves the dots when the mouse drags them :
public class Envelope : MonoBehaviour
{
LineRenderer lineRenderer;
// Start is called before the first frame update
void Start()
{
lineRenderer = GetComponentInChildren<LineRenderer>();
}
// Update is called once per frame
void Update()
{
var points = GetComponentsInChildren<EnvelopePoint>().Select(ep => ep.transform.localPosition).ToArray();
lineRenderer.positionCount = points.Length;
lineRenderer.SetPositions(points);
}
}
public class EnvelopePoint : MonoBehaviour
{
[SerializeField] bool isHeld = false;
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
if (isHeld)
{
// Vector3 mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
Vector3 mousePos = Input.mousePosition;
transform.position = mousePos;
}
}
private void OnMouseDown()
{
isHeld = true;
}
private void OnMouseUp()
{
isHeld = false;
}
}
The best result is to put the envelope outside of the canvas.
The lines render well to where the points are but im not able to convert the mouse position to correct coordinates for the dots. When i click on a dot to drag it the dot snaps to a position a bit lower and a bit to the left of the mouse. Like this:
https://imgur.com/3KK6VD3
But then i can drag the dots and the lines adjust perfectly.
I guess i have two questions:
How should i get the mouse position conversion correctly?
Is this a strange or over complicated way of doing this? Is there a more reasonable way?
Id love some tip as well on what i should read up on to better understand the different screen types and how to convert between them.
RectTransformUtility.ScreenPointToWorldPointInRectangle: Transform a screen space point to a position in world space that is on the plane of the given RectTransform.
There is also ScreenPointToLocalPointInRectangle but since you are modifying Line Renderer's points (which are in world space), I think ScreenPointToWorldPointInRectangle best suits your needs.
I'm currently experiencing a coder's block right now as I'm trying to instantiate text on a game object, specifically a Zombie prefab. I've gotten down the enemy's position for the text to be spawned but can't seem to make it follow the zombie's movement as it walks towards the player.
This is my 'Word Spawner' script.
public GameObject wordpb; // my word prefab
public Transform canvas; // connected to a canvas ui that has world camera set
public EnemyOne enemy;
public DisplayWord Spawn()
{
Vector2 targetPos = new Vector2(enemy.transform.position.x, enemy.transform.position.y);
GameObject wordobj = Instantiate(wordpb, targetPos, Quaternion.identity, canvas);
DisplayWord displayWord = wordobj.GetComponent<DisplayWord>();
return displayWord;
}
and this is where the DisplayWord class is derived from.
public Text text;
public void SetWord(string word)
{
text.text = word;
}
public void ThrowLetter()
{
text.text = text.text.Remove(0, 1);
text.color = Color.red;
}
public void ThrowWord()
{
Destroy(gameObject);
}
My best guess is that I should be implementing a void Update method in which I use transform.Translate? Or should I put a placeholder that acts as a child class to my Zombie prefab and attach the DisplayWord script there? Please help a poor soul out.
How does the text relate to the Zombie game object? Knowing what the text is for in relation to the zombie might inform the best way to make it follow the game object.
If the text is something like a worldspace nametag, instead of translating in Update you could make the text a child of the game object it needs to follow. It might not be the most elegant solution but if you give each text its own worldspace canvas you could assign the text as a child of the zombie, or, if you know you'll always have text following a zombie, you could just add a worldspace canvas and text to the zombie prefab...
To instantiate as a child you'd need to rework your word prefab to be its own worldspace canvas with your text as its child.
You can assign a parent when you instantiate:
wordobj = Instantiate(wordpb, enemy);
Or set the parent after instantiation:
wordobj.transform.SetParent(enemy.gameObject.transform, true);
The second parameter in SetParent is 'worldPositionStays', and controls whether the child object keeps its world position (true) or whether it's transform is evaluated relative to its new parent's transform. You could make it work either way: if you leave it 'true' you don't need to change the rest of your code, but I think if you make it false you don't need to get the enemy GameObject's position... The same is true for Instantiate when a parent is assigned but no transform position/rotation. So I think you could skip the step of finding the enemy's position and rewrite your Spawn code to:
public GameObject wordpb; // my word prefab
public EnemyOne enemy;
public DisplayWord Spawn()
{
GameObject wordobj = Instantiate(wordpb, enemy, false);
DisplayWord displayWord = wordobj.GetComponent<DisplayWord>();
return displayWord;
}
You'd need to assign the newly instantiated canvas's worldspace camera to make this work...
I'm trying to follow the instructions in the unity documents how to use Inverse Kinematics in this page:
Inverse Kinematics
But i don't have the IK Animator Controller when i select Controller for the Animator.
I tried adding the script now. But the hand the right hand is folded to the other side. It's not like it's holding the flash light: The script is attached to the ThirdPersonController. And i dragged to the script in the Inspector to the rightHandObj the EthanRightHand and to the lookObj i dragged the Flashlight.
But the hand seems to be wrong way.
This is the script i'm using now the IKControl:
using UnityEngine;
using System;
using System.Collections;
[RequireComponent(typeof(Animator))]
public class IKControl : MonoBehaviour
{
protected Animator animator;
public bool ikActive = false;
public Transform rightHandObj = null;
public Transform lookObj = null;
void Start()
{
animator = GetComponent<Animator>();
}
//a callback for calculating IK
void OnAnimatorIK()
{
if (animator)
{
//if the IK is active, set the position and rotation directly to the goal.
if (ikActive)
{
// Set the look target position, if one has been assigned
if (lookObj != null)
{
animator.SetLookAtWeight(1);
animator.SetLookAtPosition(lookObj.position);
}
// Set the right hand target position and rotation, if one has been assigned
if (rightHandObj != null)
{
animator.SetIKPositionWeight(AvatarIKGoal.RightHand, 1);
animator.SetIKRotationWeight(AvatarIKGoal.RightHand, 1);
animator.SetIKPosition(AvatarIKGoal.RightHand, rightHandObj.position);
animator.SetIKRotation(AvatarIKGoal.RightHand, rightHandObj.rotation);
}
}
//if the IK is not active, set the position and rotation of the hand and head back to the original position
else
{
animator.SetIKPositionWeight(AvatarIKGoal.RightHand, 0);
animator.SetIKRotationWeight(AvatarIKGoal.RightHand, 0);
animator.SetLookAtWeight(0);
}
}
}
}
Add an empty game object to the flashlight and target that instead of the flashlight object itself. Hit play and then fiddle with the placement of the empty object until it is where you want it. Then just turn the flashlight into a prefab, stop play mode and make sure the flashlight in the scene matches the prefab (you can just use revert to do that if needed).
Now it would be doing exactly what you want every time. You could even have multiple prefabs with the empty object positioned differently to allow characters with larger or smaller hands to hold it convincingly.
I have made a gameobject together with some children gameobject to represent the information to show up when specific circumstances occurred.
I have already ajusted the position of the information gameobject(together with its' children) in the cameraarea. The thing is that I want to move the gameobject(together with its' children) out of the camera, maybe on top or maybe on left. Following is the scratch to demonstrate the position I want to put it:
So that I could move the information gameobject and its' children (Red box) with some movement effect when needed, I have no problem with moving it back but could find an elegant way to move it out of the camera when the game started.
Mostly because I don't know how to calculate the position out of the camera.
Maybe find the upper border of the camera and the size of the gameobject and its children?
I know I could do this by maybe add a marker gameobject to represent the downer border of the information gameobject, and move it until it's not visible, but is there a more elegant way?
Any ideas?
For this one, I would use the following trick: use any method (animation, coroutine, Update method...) to move your item out of screen the way you desire. Then you can use the OnBecameInvisible event which is called when the item does not need to be rendered on any camera anymore. The event will there be used to detect that the parent object moved out of screen, and that you want to stop the current movement. You then just need to define in this event that you want to stop the current moving behavior, and you will be done.
void OnBecameInvisible() {
// Stop moving coroutine, moving in Update or current animation.
}
There are probably more elegant ways of doing it as you said, but I think this method should be enough for what you want to achieve.
It took me time, but I found this way for you, attach this script to your gameObject:
public Renderer rend;
//drag the camera to the script in the inspector
public Camera camera1;
Vector3 bottomleft;
Vector3 topright;
void Start()
{
rend = GetComponent<Renderer>();
//the top-right point of the camera bounds
topright= camera1.ViewportToWorldPoint(new Vector3(0, 0, transform.position.z));
//the bottom-left point of the camera bounds
bottomleft = camera1.ViewportToWorldPoint(new Vector3(1, 1, transform.position.z));
StartCoroutine(MoveUp());
}
IEnumerator MoveUp()
{
//while the position and the height are lower that the Y of top right
while (transform.position.y + rend.bounds.size.y < topright.y)
{
//move the object to the new position (move it up)
transform.position = new Vector3(transform.position.x, transform.position.y + .01f, transform.position.z);
//and wait for 1/100 of a second
yield return new WaitForSecondsRealtime(.001f);
}
}
you can play with the WaitForSecondsRealtime value to change the velocity of moving.