How to create a new rotation using quaternion?

I have a quaternion : [0.87497, -0.14171, -0.45028, -0.107673], and I want to set an object rotation directly using these values.

I'm looking for something along the lines of:

newObj.transform.rotation = Quaternion.<something>( 0.87497 , -0.14171 , -0.45028 , -0.107673);


What I have been doing so far is:

newObj.transform.rotation = Quaternion.identity;
newObj.transform.Rotate(rotX, rotY, rotZ, Space.World);

Where I calculate rotX, rotY and rotZ by converting quaternions into Euler angles. But I am guessing there should be a direct way of using quaternions.

 

Maybe this script will be helpful:

Code (CSharp):

1. // A quaternion is a four-element vector that can be used to encode any rotation in a 3D coordinate system.
2. // Technically, a quaternion is composed of one real element and three complex elements.
3. // https://github.com/przemyslawzaworski/Unity3D-C-programming/blob/master/quaternion.cs
4.  
5. using UnityEngine;
6.  
7. public class quaternion : MonoBehaviour
8. {
9.     Vector4 EulerToQuaternion(Vector3 p)
10.     {
11.         p.x *= Mathf.Deg2Rad;
12.         p.y *= Mathf.Deg2Rad;
13.         p.z *= Mathf.Deg2Rad;
14.         Vector4 q;
15.         float cy = Mathf.Cos(p.z * 0.5f);
16.         float sy = Mathf.Sin(p.z * 0.5f);
17.         float cr = Mathf.Cos(p.y * 0.5f);
18.         float sr = Mathf.Sin(p.y * 0.5f);
19.         float cp = Mathf.Cos(p.x * 0.5f);
20.         float sp = Mathf.Sin(p.x * 0.5f);
21.         q.w = cy * cr * cp + sy * sr * sp;
22.         q.x = cy * cr * sp + sy * sr * cp;  
23.         q.y = cy * sr * cp - sy * cr * sp;
24.         q.z = sy * cr * cp - cy * sr * sp;
25.         return q;
26.     }
27.  
28.     Vector3 QuaternionToEuler (Vector4 p)
29.     {
30.         Vector3 v;
31.         Vector4 q = new Vector4 (p.w, p.z, p.x, p.y);
32.         v.y = Mathf.Atan2 (2f * q.x * q.w + 2f * q.y * q.z, 1 - 2f * (q.z * q.z + q.w * q.w));
33.         v.x = Mathf.Asin (2f * (q.x * q.z - q.w * q.y));
34.         v.z = Mathf.Atan2 (2f * q.x * q.y + 2f * q.z * q.w, 1 - 2f * (q.y * q.y + q.z * q.z));
35.         v *= Mathf.Rad2Deg;
36.         v.x = v.x>360 ? v.x-360 : v.x;
37.         v.x = v.x<0 ? v.x+360 : v.x;
38.         v.y = v.y>360 ? v.y-360 : v.y;
39.         v.y = v.y<0 ? v.y+360 : v.y;
40.         v.z = v.z>360 ? v.z-360 : v.z;
41.         v.z = v.z<0 ? v.z+360 : v.z;
42.         return v;
43.     }
44.  
45.     void Start()
46.     {
47.         Vector3 euler = new Vector3(Random.Range(-360f,360f),Random.Range(-360f,360f),Random.Range(-360f,360f));
48.         Vector4 quaternion = new Vector4 (this.transform.rotation.x,this.transform.rotation.y,this.transform.rotation.z,this.transform.rotation.w);
49.         Debug.Log(EulerToQuaternion(euler).ToString("F8"));  
50.         Debug.Log(Quaternion.Euler(euler).ToString("F8"));
51.         Debug.Log(QuaternionToEuler(quaternion).ToString("F8"));
52.         Debug.Log(this.transform.rotation.eulerAngles.ToString("F8"));
53.     }
54. }

 

You mean like this?

Code (csharp):

1.  
2. newObj.transform.rotation = new Quaternion(0.87497, -0.14171, -0.45028, -0.107673);
3.