Question Rotate Vector3 Based on the Rotation of a Transform

This was sort of hard to google down because googling only gives very basic guides on how to rotate a transform. In my particular case, I have a transform that has some arbitrary rotation, and then I have a Vector3 which has some direction, let's say it's pointing up.

I now want to be able to rotate this vector based on the rotation on the transform, so that if the transform is upside down, the vector is now point down instead of up.

Cheers!

 

Never Mind, I found it when looking through the Quaternion Methods.

Quaternion.FromToRotation(myVector, transform.rotation.eulerAngles).eulerAngles;

 

Hm, not sure about that one. Anytime you reach into .eulerAngles you are setting yourself up for lots of future confusion and weird edge case bugs. Here's why:

All about Euler angles and rotations, by StarManta:

https://starmanta.gitbooks.io/unitytipsredux/content/second-question.html

Based on your description:

you just multiply the Vector3 by the Quaternion:

Code (csharp):

1. Vector3 myRotatedVector = transform.rotation * myOriginalVector;

That's it.

 

You're right. I though it was working but it was just on that instance that made it look like it was working. I stumbled across this solution on some other forum, but thanks anyway!