How to make Quaternion a negative

Questions & Answers
1

Hi All!

I got this script hanging on a Cube skybox, wich is a child of the main camera. It has to rotate horizontally against the rotation of the camera.

How do I make a variable that is the negative of the Camera’s rotation? This is the script I got so far.

function FixedUpdate()
{
var rot1 = Camera.main.transform.rotation;
print(rot1);
transform.rotation = rot1;
}

So, in short: How do I make var rot1 a negative? It returns values like this: (0.0, 1.0, 0.0, 0.1)

Thanks in advance!!

3

Maybe Quaternion.Inverse()

4

Ehm actually Quaternion.Inverse() will invert the rotation so you need to set the localRotation to the inverse of the camera. But it’s much simpler to set the .rotation to Quaternion.identity.

.rotation is the rotation in world-space. Setting it to identity will keep the skybox-rotation always world aligned.

Also don’t use FixedUpdate() it’s the physic-loop and has nothing to do with the visual result. LateUpdate is the place to go:

function LateUpdate()  
{  
    transform.rotation = Quaternion.identity;  
}

Another way is to keep the skybox as a seperate object and just move it along with the camera. That way the rotation won’t change :wink:

var camera : Transform;
function LateUpdate()  
{  
    transform.position = camera.position;  
}
2

In theory you would negate the 4th element. But maybe you need to convert it to Axis-Angle first, then negate the angle, then reconvert back to Quaternion. All those api’s exist.

Sounds like an interesting skybox. How is it different from a normal one, like you set in the Rendering settings?