I wrote a custom renderer to represent a min and a max Radius. In some cases the renderer is not working as expected. It looks like the overlay is getting cut of by the map tiles.
Here is how I did it. Did I miss something?
class RadiusOverlayRenderer: MKOverlayRenderer {
override func draw(_ mapRect: MKMapRect, zoomScale: MKZoomScale, in context: CGContext) {
guard let overlay = self.overlay as? RadiusOverlay else {
return
}
let maxRadiusRect = self.rect(for: overlay.boundingMapRect)
.offsetBy(
dx: CGFloat(-overlay.boundingMapRect.height)/2,
dy: CGFloat(-overlay.boundingMapRect.width)/2
)
let minRadiusRect = CGRect(
x: Double(maxRadiusRect.midX)-overlay.minRadRect.width/2,
y: Double(maxRadiusRect.midY)-overlay.minRadRect.height/2,
width: overlay.minRadRect.width,
height: overlay.minRadRect.height)
let aPath = CGMutablePath()
aPath.addEllipse(in: maxRadiusRect)
aPath.addEllipse(in: minRadiusRect)
aPath.closeSubpath()
context.setFillColor(overlay.color.cgColor)
context.setAlpha(overlay.alpha)
context.addPath(aPath)
context.drawPath(using: .eoFillStroke)
}
}
Notice that only the upper left parts are clipped?
with .offsetBy
you are drawing outside of the .boundingMapRect
.
Remove the .offsetBy...
If you want to draw your circle at a different place, then adjust coordinate
and / or boundingMapRect
of your MKOverlay
.