Quaternions to Rotator (FQuat and FRotator) How can I convert?

Development Programming & Scripting C++
1

Hi,

I have data in the form of Quats streaming in w, x, y, z.

I’m a bit confused as to how I can apply this in Unreal to my Actor object. Do I need to convert this explicitly to a Rotator first?
Ideally I would like the result to be accessible in Blueprints with UPROPERTY

This is what I have currently that seems to do nothing:



FQuat myQuatToRot(IncomingStruct.wRot, IncomingStruct.xRot, IncomingStruct.yRot, IncomingStruct.zRot);
FRotator myRot(myQuatToRot);
IncomingStruct.calculatedRotator = myQuatToRot.Rotator();

Help !

2

Quaternion functions aren’t really exposed to Blueprint, since they aren’t very artist/content-creator friendly. Usually you just convert to/from FRotator if you need to pass rotation information in and out of Blueprint.

You say your code does ‘nothing’ – what is it supposed to do?

3

Perhaps I can give you a bit more of an outline of what I’m trying to achieve:

Data is streaming to the game in Quaternion format. When I convert this to Rotator(Euler), It seems to be working in only 1 axis. However the same data converted in other software is producing valid angles.

I suspect it might be a euler lock/flip issue so I was hoping to eliminate that by applying the quaternions to the object in Unreal to see if it solves it.

4

Exposing the UPROPERTY to Blueprint should be fine if you want it to return a Rotator. You can return a Quaternion but you can’t do much with them in Blueprint, if anything.

What’s the purpose of the second line in that code snippet you posted?