Rotate a mesh around it's center using quaternion

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I would like your help if possible as i don’t know a lot of quaternion me myself.

so i have a cylinder and i want to rotate around the up vector as its axis of rotation when i press up or down arrows or swipe on touch.and i want to rotate it around the right vector when i swipe left or right, or pressing left and right keys on keyboard.

My current setup is this

Imgur

and this is the cylinder i want to rotate.

Imgur

So basically, i want when i press the up or down keys (or in case of mobile to swipe up or down) is to rotate around the green arrow and when pressing left and right i want to rotate around the red arrow.

I use quaternion bleuprint plugin found here Blueprint Quaternion Library in Code Plugins - UE Marketplace

you can check the photos of the plugin for all of the available nodes.

i would appreciate any help.

Many Thanks

2

This tutorial will show you how to use quaternions for rotations.

Haven’t bought that quaternion plugin so I can’t say for sure what to use from there but the nodes should largely be similar. Looking up in the FQuat API there is a C++ function “Make From Euler” this is probably what you will want to use as a blueprint node if the plugin has make that accessible to you.

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Please check the gif so you know what’s my problem

my current blueprint setup is

270277-capture.png
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i’m able to rotate around the up vector as my axis of rotation for left and right panning.

but for up and down panning weird issue happens.
i think because of the Euler gimbals lock.

4

i was able to solve the problems using those nodes.

270405-capture.png
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270404-capture1.png
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This was used with quaternion plugin to find the quat at the y axis and to rotate the object around it

5

To orientation vector dont exits anymore, new name ?

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6

Just for the future - in C++ you can simply rotate by FQuats

const FQuat  curretnQuatRotation = FQuat(YOUR FRotator Rotation);
const FQuat CurRelRotQuat = FQuat(FRotator(DeltaPitch, DeltaYaw, DeltaRoll));
const FQuat NewRelRotQuat = CurRelRotQuat * curretnQuatRotation;

In blue print simple use Add Local Rotation function of the object.

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