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Hey, I'm trying to find the angle of an object from a certain point. I've tried a few things nothing seems to be working properly. I suck at explaining so here's a little drawing of what I mean:

alt text

Answer 1

0

  var findAngle = false;
  var findingAngle = false;
  var lastPosition : Vector3;
  var currentAngle : float;

  function Update() {

         if(!findAngle) findingAngle = false;
         if(findAngle && !findingAngle) {
             lastPosition = transform.forward;
             findingAngle = true;
         }
         if(findingAngle) {
              currentAngle = Mathf.Acos(Vector3.Dot(lastPosition, transform.forward));
         }


  }

This tells you the angle between the two vectors - but it's only good for 180 degrees and it will be positive no matter which way the rotation happens - did you want something else?

answered Jun 24 '12 at 01:16 AM

whydoidoit
33.1k ● 12 ● 23 ● 101

This might work, let me give it a shot!

Jun 24 '12 at 01:25 AM commodore

hm... there's no way to check if it goes past 180 either way is there?

Jun 24 '12 at 01:45 AM commodore

@commodore: Best way to do it is to use the vector difference between the two points and Pythagorean's Theorem.

Jun 24 '12 at 01:51 AM Mizuho

@commodore Ah damn I was afraid you were going to say that :)

Jun 24 '12 at 02:21 AM whydoidoit

Try this:

 var findAngle = false;
  var findingAngle = false;
  var lastPosition : Vector3;
  var currentAngle : float;

  function Update() {

         if(!findAngle) findingAngle = false;
         if(findAngle && !findingAngle) {
             lastPosition = transform.right;
             findingAngle = true;
             currentAngle = 0;
         }
         if(findingAngle) {
              var newAngle = Mathf.Acos(Vector3.Dot(lastPosition, transform.forward));
              currentAngle += (newAngle-90);
              lastPosition = transform.right;
         }


  }

Jun 24 '12 at 02:24 AM whydoidoit

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Answer 2

0

#pragma strict

var findAngle = false;
var reference : Vector3;
var angle : float;

function Update () {
    if(Input.GetKeyDown(KeyCode.N)) findAngle = !findAngle;
    if(findAngle) {
        reference = new Vector3(1, 0, 0); // Direction 0 degrees is in (currently positive x axis)
        angle = Vector3.Angle(reference, transform.position);
       if(transform.position.z - reference.y < 0) {
         angle = 360 - angle;
       }
    }
}

Here's the updated function. It uses the positive x axis as 0 and counts degrees counter-clockwise.

Edit: Cleaned the code up.

answered Jun 25 '12 at 05:47 AM

Mizuho
392 ● 3 ● 5 ● 6

Maybe I'm just implementing your code wrong. It only gives me a value around 1.4.. Thanks for helping and sorry if I'm annoying or too much of a noob to understand

if(Input.GetKey("h"))
{
    findAngle = true;
}
else
{
    findAngle = false;
}   

if(findAngle) 
{
    // Or whatever point you're basing this off...
    reference = Vector3.zero;
    vector = transform.position - reference;
    angle = Mathf.Atan(vector.z / vector.x);
    if(vector.z > 0) angle += 180;
}

Debug.Log("Angle since findAngle turned true: "+angle);

Jun 27 '12 at 12:59 AM commodore

Gimme a second to throw this into my testing grounds then. I'll be back in about 10 minutes...

Jun 27 '12 at 01:06 AM Mizuho

Thank you! I'll take a little screencap of my problem. It's most likely a problem on my end.

Jun 27 '12 at 01:08 AM commodore

I included the debugger so you could see when I'm pressing "h"

http://www.youtube.com/watch?v=0sfcMIYt6j4&feature=youtu.be

Jun 27 '12 at 01:24 AM commodore

That took a looong time (sorry, I became very bad at math), but I figured out a foolproof way of doing it! See my updated answer.

Jun 27 '12 at 01:34 AM Mizuho

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