Develop Reference

Moving a game object in Arcore

I have been working out on google ARCore, and got stuck on how to move the game object with the inputs coming from the android device.
The canvas that i have created is precisely with 4 buttons, which as AxisTouchButton script from cross platform input covering vertical and horizontal. I have tried out lean touch to scale, translate and rotate seems to works perfectly.But when i am trying to apply force or velocity to the game object, it moves perfectly for the first time, then when i again axis the buttons, it starts to float in that particular direction unless any other button is pressed.
The below code is for the movement of the game object attached to the Andy prefab in HelloAR scene from examples :
Vector3 offset=Vector3.zero;
offset.x = CrossPlatformInputManager.GetAxis("Horizontal");
offset.z= CrossPlatformInputManager.GetAxis("Vertical");
rb.velocity=(offset * speed ) ;

I'm not sure why your prefab is drifting with the code snippet you've provided,
Try resetting the velocity to zero after you are done with movement of prefab.
rb.velocity = new Vector3(0,0,0);
Or maybe it is due to the fact that you are moving the prefab too far away from its parent anchor, or maybe away from the plane detected by arcore.
But I've another tested way to move a prefab using touch input on the planes detected by arcore and as it allows you to move the prefab only on the planes detected so you can easily reset its anchor after you are done with replacing prefab.
I'd modified the HelloARController.cs script in the following way.
bool move = false; //handle move with some button calls
void Update(){
//add this in your update method to call MoveObject() method
//handle move with some buttons
if(move){
MoveObject();
}
}
void MoveObject(){
if(Input.touchCount == 1){
Touch touch = Input.GetTouch(0);
TrackableHit hit;
TrackableHitFlags raycastFilter = TrackableHitFlags.PlaneWithinPolygon | TrackableHitFlags.FeaturePointWithSurfaceNormal;
if (Frame.Raycast (touch.position.x, touch.position.y, raycastFilter, out hit)) {
if ((hit.Trackable is DetectedPlane) && Vector3.Dot (firstPersonCamera.transform.position - hit.Pose.position, hit.Pose.rotation * Vector3.up) < 0) {
Debug.Log ("Hit at back of the current detected plane");
}
else {// KEY CODE SNIPPET : moves the selectedObject at the location of touch on detected planes
selectedObject.transform.position = hit.Pose.position;
}
}
else {
Debug.Log ("Not moving");
}
}
}
here selectedObject is you andy prefab of whatever you are instantiating.
Make sure that you are instantiating only one prefab at a time and refer it to selectedObject.

Try out the new ARCore Manipulation System. Working like a charm (for newbies).
They forgot to add a collider on the prefab, so don't forget to add it before running the example.
ARCore Unity SDK v1.13.0

Unity3D touch event binding

I have created a button in my 2d game using Unity3d, added box collider 2d with name PADBASE to detect touch events this way:
if(Input.touchCount > 0)
{
for(int i = 0; i < Input.touchCount; i++)
{
Vector3 mouseWorldPos3D = Camera.main.ScreenToWorldPoint(Input.GetTouch(i).position);
Vector2 mousePos2D = new Vector2(mouseWorldPos3D.x, mouseWorldPos3D.y);
Vector2 dir = Vector2.zero;
RaycastHit2D hit = Physics2D.Raycast(mousePos2D, dir);
Touch t = Input.GetTouch(i);
if (hit.transform != null)
{
if(Physics2D.Raycast (hit.transform.position , hit.transform.forward))
{
GameObject recipient = hit.transform.gameObject;
if(t.phase == TouchPhase.Began) //poczatek dotyku
{
// button clicked
// change colour to red to visually show that button is being pressed
}
else if (t.phase == TouchPhase.Ended)
{
// change collor to its default colour to visually show that its no longer pressed
}
}
}
}
}
And lets assume I will change button colour to red when player touched the button, and back to its default colour when he released his finger (for example)
Now it will obviously work only when player will release his finger, as long as his finger is actually inside bounds of the box collider, what I am trying to do is "bind touch events(?)" to still catch touch event (slide or ended) even if player moved his finger outside of the collider without releasing his finger (for example accidentally)
I am looking forward for some suggestions, thanks.
In my game I will have multiple buttons so multi touch is necessary.

Solved, it actually turns to be really easy, you need to store and compare touch finger ID.
Solution:
- on touch began:
check if touch is withing game objects box collider like in the code attached above.
get touch finger ID and pass it to your button or keep reference of it
- on touch ended:
compare touch finger ID with your stored touch id, if they are equal, set your stored finger id to -1 and perform your code that should execute on touch edned
- on touch moved or (||) stationary:
do the same comparison of the touch id like in the touch ended, and perform your code that should be executed if player will slide/move his finger, but do not modify your finger id variable.
That`s it, works well with multiple buttons with multi touch.

Unity3d - Touch Input issue

I develop a game that need user to have a single touch to draw over to link multiple objects. Currently using mouse button as touch input with this code:
if(Input.GetButton("Fire1"))
{
mouseIsDown = true;
...//other codes
}
It works fine with mouse but it will give me problem when I compile it for multi touch device. In multitouch device, if you have 2 fingers down, the middle point will be taken as the input. But if I already touch an object then with second finger down to screen, it will mess up my game input and give me havoc design.
What I want is to limit it to 1 touch only. If the second finger come touching, ignore it. How can I achieve that?

Below is all you need:
if ((Input.touchCount == 1) && (Input.GetTouch (0).phase == TouchPhase.Began)) {
mouseIsDown = true;
...//other codes
}
It will only fire when one finger is on the screen because of Input.touchCount == 1

You are using Input.GetButton. A button is not a touch. You probably want to look at Input.GetTouch
If you need to support multiple input-type devices, you may want to consider scripting your own manager to abstract this out somewhat.

I would roll with a bit of polling!
so in your Update() I typically do something like this:
foreach (Touch touch in Input.touches)
{
// Get the touch id of the current touch if you're doing multi-touch.
int pointerID = touch.fingerId;
if (touch.phase == TouchPhase.Began)
{
// Do something off of a touch.
}
}
If you're looking for more info check this out:
TouchPhases in Unity

Moving object to touch position acting unexpectedly

Good evening, quick question.
Im developing a top-down 2D platformer game in Unity3D. Here is a picture of the game.
I have pretty much everything worked out on a desktop, but when attempting to set up the controls for mobile, I can't seem to get it to work the way it should. All I need is to get the player to move in the direction of wherever the user touches the screen. With the current code im using, the player just rotates in 4 directions, up, down, left and right. He also moves a little, but never goes far from his spawn point.
Please take a look at my revised code:
public Camera camera;
public float movespeed = 0;
// Use this for initialization
void Start () {
movespeed = 2.75F;
}
// Update is called once per frame
void Update () {
if (Input.touchCount > 0) {
// The screen has been touched so store the touch
Touch touch = Input.GetTouch(0);
if (touch.phase == TouchPhase.Stationary || touch.phase == TouchPhase.Moved) {
// If the finger is on the screen, move the object smoothly to the touch position
Vector3 touchPosition = camera.ScreenToWorldPoint(new Vector3(touch.position.x, touch.position.y, -13));
Quaternion rot = Quaternion.LookRotation(transform.position - touchPosition, Vector3.back);
transform.rotation = rot;
transform.eulerAngles = new Vector3 (0, 0, transform.eulerAngles.z);
rigidbody2D.angularVelocity = 0;
//float input = Input.GetAxis ("Vertical");
transform.position = Vector3.Lerp(transform.position, touchPosition, Time.deltaTime);
}
}
}
}
Any ideas on how I can get my player to move to the touched are of the screen? Any help would be much appreciated. Thanks in advance.

If I have understood correctly, you want your player game object to move towards the point on the screen that is being touched. I think it's probably best to describe the behavior of your code so that you can hopefully better understand what might be happening.
From the code posted, I can see one possible issue. Look again at this line:
Quaternion rot = Quaternion.LookRotation(transform.position - touchPosition, Vector3.back);
Here, you are asking Unity to calculate the unit quaternion that represents a rotation from the direction of Vector3.forward to the direction from of the player game object from the touch position. This probably isn't what you want. From the description of the problem, you want the game object to rotate to face the point on the screen being touched (rather than the opposite direction). You can either change the order of the subtraction operands or, preferably, use instead the Transform.LookAt method.
After this, you update the transform's rotation:
transform.rotation = rot;
That's fine, but note that you wouldn't need to do this when using Transform.LookAt.
You then set the transform's rotation again using in this line:
transform.eulerAngles = new Vector3 (0, 0, transform.eulerAngles.z);
I'm not entirely sure why you are doing this. If you only want one axis of rotation, you can use, for example:
transform.LookAt(new Vector3(touchPosition.x, touchPosition.y, transform.position.z))
This should rotate the player's transform around the z-axis to look in the direction of the point being touched.
Finally, you linearly interpolate the transform's position from its current position to the point being touched:
transform.position = Vector3.Lerp(transform.position, touchPosition, Time.deltaTime);
This isn't necessary. Instead, you should just move the player's transform forward. The player should be looking in the direction of the touched screen point. Hence, translating the player forward will move the player towards said screen point:
transform.position += transform.forward * speed * Time.deltaTime;
When the player is very close to the touched screen point it will overshoot and immediately rotate to look in the opposite direction. This will occur repeatedly. You should include some distance that specifies when the player is assumed to have reached the target point.

Dragging Camera based on Touch (Unity)

In my game, I want the camera to move based on the user swiping their finger. My issue is that when someone removes their finger from the screen, and places it down again, the camera jumps to a new position... I am guessing it has to do with the coordinates, I say this because if I click somewhere far from where I removed my finger from the screen, the camera jumps. Here is the code:
var speed : int = 1;
var lastPoint : Vector2; //make this private if you want to.
function Update()
{
var offset : float; //offset of the touch from last frame
if(Input.touches.Length 0)//make sure we have a touch in the first place
{
var evt : Touch = Input.touches[0]; //setting up touch events so we can get fancy.
if(evt.phase == TouchPhase.Began) //this is the first frame the screen has been touched for, simply save the point.
{
lastPoint == evt.position;
}
else if(evt.phase == TouchPhase.Moved
{
offset = evt.position.x - lastPoint.x ;//take the difference
//I'm going to use Transform.Rotate because it's handy dandy
transform.Rotate(0,offset * speed,0);
//save the new "lastPoint"
lastPoint = evt.position;
}
else if(evt.phase == TouchPhase.Ended)
{
//If you want the object to drift after you spin it you can make a function to go here.
//To do this, take the speed of the rotation and continue to rotate all while subtracting off of the speed.
//I would use the Transform.Rotate function on this too.
//If you need me to I could write this function too.
}
}
}
What is the solution to have the camera resume, and not jump once someone puts their finger down again?
I am also willing to redo it, if there is a better solution/more efficient method of solving the issue..
Thanks a lot!

The supplied code seems fine, all you need to do is when the user is not pressing, you update the lastPoint every frame. Or if you know when the user start to press, just set the lastPoint to the current pos before calculating the offset. This way the offset is zero the first frame the user touch the screen.