iOS 8 popoverpresentationcontroller popoverlayoutmargin not working

Question

I am using the new popOverPresentationController to present UIPopOverController in iOS 8. I set the popOverLayoutMargins with a value like

Answer 1

It works on iOS 13 now.

I guess the arrow point origin maybe follow this expressions

let xRatio = (permittedArrowDirections is horizonal) ? 1/2 : 1
let yRatio = (permittedArrowDirections is vertical) ? 1/2 : 1

x =  sourceRect.origin.x + sourceRect.size.width * xRatio + popoverLayoutMargins.left
y =  sourceRect.origin.y + sourceRect.size.height * yRatio + popoverLayoutMargins.top