koobas.hobune.stream
[HELP] [2D] Launch an object in a particular direction
So, I'm making a game (for touchscreen) for my college project. In this project, I want to launch a ball in the direction where user want's it to.
[What currently do I have?]:
if (Input.GetMouseButtonDown(0)){
hasStarted = true;
print ("Left Mouse button clicked");
this.GetComponent<Rigidbody2D>().velocity = new Vector2 (2f,7.5f);
}
[Behavior I need]:
Ball should have a ray emerging from it in upward direction, the user should be able to move this ray between 10'o clock and 2'o clock.
After the user has acquired the direction he wants to point, he may tap on the screen to launch the ball (or maybe a button maybe used to launch the ball).
Can you please help me out with this?
So, I found the answer myself :D
1) For creating a ray, Just go here and copy down the script he has shown in the video ( Just remove the if (counter > dist) condition )
Link : https://www.youtube.com/watch?v=Bqcu94VuVOI
Let pointA be the ball, and pointB be an empty gameObject in the heirarchy. To move the ray, just move the pointB left or right, below is a script that I attached to pointB for moving it.
public float speed = 15.0f;
public float padding = 1.0f;
float xmin;
float xmax;
// Use this for initialization
void Start () {
float distance = transform.position.z - Camera.main.transform.position.z;
Vector3 leftmost = Camera.main.ViewportToWorldPoint(new Vector3(0,0,distance));
Vector3 rightmost = Camera.main.ViewportToWorldPoint(new Vector3(1,0,distance));
xmin = leftmost.x + padding;
xmax = rightmost.x - padding;
}
// Update is called once per frame
void Update () {
if (Input.GetKey(KeyCode.LeftArrow)){
transform.position += Vector3.left * speed * Time.deltaTime;
}
if (Input.GetKey(KeyCode.RightArrow)){
transform.position += Vector3.right * speed * Time.deltaTime;
}
float newX = Mathf.Clamp (transform.position.x, xmin, xmax);
transform.position = new Vector3 (newX, transform.position.y, transform.position.z);
}
I didn't had laser material, so I used flame material given in the standard assets of Unity 5.3.5f. And make the ray inActive after launching the ball. 
2) To launch the ball in particular direction go here, http://answers.unity3d.com/questions/315780/fire-a-projectile-towards-a-specific-object.html
Just instead of clone.velocity, use this.GetComponent<Rigidbody2D>().velocity
I used
this.GetComponent<Rigidbody2D>().velocity = (ptB.transform.position - transform.position).normalized * speed;
