i have a Vector3 represents an Orientation in 3D , how to convert it to the corresponding Quaternion ? is there any quick way ?
EDIT : i want to add an angular velocity vector to the Orientation Quaternion of the body
On the other hand, if you're not storing an euler angle, but just the direction (or forward vector) of the camera/object, then bear in mind that generally a single 3D vector is not enough to store a complete orientation in 3D space unless you restrict one of the axes of rotation.
A typical case is where your camera/object can't roll or flip around and the Up vector is always pointing in the upper direction, e.g. FPS camera. If that's the case, then you should create a rotation matrix from your forward vector, and then use the following static method:
As for creating that rotation matrix, I think something like this should work (I hope so, I'm a little rusty with cross products):
I think this may cause problems though if you try to look directly up or down, or close to those orientations, so you may need to handle those cases separatedly.