Smaller brush is darker than larger brush

[ulitiy]

Some significant issue with opacity calculation, blending mode or overlapping? It should be exactly the same color.

related #82

[ulitiy]

https://www.wolframalpha.com/input/?i=area+of+symmetric+lens

probably this should help with calculating overlaps

[ulitiy]

        let n = Int(brush!.pointSize / brush!.pointStep)
        let overlapMultiplier = Array(1...n).map { (el: Int) -> CGFloat in
            let d = brush!.pointStep * CGFloat(el) / brush!.pointSize // normalised distance between point centers
            let gendia = sqrt(4.0 - d*d )
            return CGFloat.pi - d/2.0 * gendia - 2.0 * atan(d/gendia)
        }.reduce(0, +)

@Harley-xk I used this code and it seems to provide more consistent result.

[ulitiy]

Nevermind, my bad, it's pretty much the same.