I have a drawing app that I created and have sold on the App Store since 2018. It requires an Apple Pencil. My app uses the azimuth feature to orient the brush pattern that is drawn on the screen. A user just contacted me and said his azimuth feature is not working. Now it works fine for me, and I have not heard complaints from other users, so this leads me to believe it could be a problem with his Pencil. I wanted to show my code just to rule out that the problem is on my end and also get suggestions on what I should tell this user to do. Should he just contact Apple about it?
// calculate the pencil direction
let vector1 = touch.azimuthUnitVector(in: selectedCanvas)
let angle = atan2(vector1.dy, vector1.dx)
let azimu = angle - CGFloat(Double.pi) / 2.0
// adjust for wonky azimuth rotation translation
if azimu >= -4.5 && azimu <= 0 {
rot = abs(azimu)
} else {
rot = 6.2 - azimu
}
The azimu is then used as a point rotation in a basic Bézier curve and drawn on the screen.
If it works on one iPad, it should work on all of them, right? He’s using an iPad Pro and so am I. I asked if he was using an Apple Pencil and he said yes.