For an AR iOS app I'm making, I want to rotate a 3D model using Quaternions. After getting the quaternion rotation instruction completely wrong, I realized... hmmm I am definitely lacking something in my understanding. Why would it fly up to the ceiling?!?!
I'm familiar with matrix manipulations, but I don't have the visual intuition for some of the operations. Happily, YouTube exists and I found the wonderful 3Blue1Brown.
I'll be noting what I learn brushing up on Linear Algebra & Quaternions.