Merge connected UIBezierPaths - objective-c

Question

Is there some way (code or pseudo-code algorithm) to utilize UIBezierPath instance methods like appendPath to "merge" any number of connected, distinct UIBezierPaths into a single big path? In a document with many paths, I am trying to reduce the encoded file size by perhaps reducing the number of paths as there is surely some redundant information there. If I am barking up the wrong tree, let me know.

Answer 1

In my case, I had few logically connected paths that together form a closed shape and I wanted to fill this closed shape. This cannot be done if you just append(_:) them together as the fill would simply applied to each path. I looked at similar questions asked but none of them solved the problem. So I wrote this extension to merge logically connected paths together to form a single path.
If you have path1, path2 and path3 logically form a closed shape. Call them in the same order
let mergedPath = UIBezierPath()
mergedPath.merge(with: path1)
mergedPath.merge(with: path2)
mergedPath.merge(with: path3)
import UIKit
extension UIBezierPath {
func merge(with path: UIBezierPath) {
let currentPath = self.cgPath.mutableCopy()!
let lastPoint = self.lastPoint()
let firstPoint = path.firstPoint()
var index = -1
path.cgPath.applyWithBlock { block in
index += 1
let element = block.pointee
switch (element.type) {
case .moveToPoint:
if index != 0 && lastPoint != firstPoint || lastPoint == nil {
currentPath.move(to: element.points[0])
}
case .addLineToPoint:
currentPath.addLine(to: element.points[0])
case .addQuadCurveToPoint:
currentPath.addQuadCurve(to: element.points[1], control: element.points[0])
case .addCurveToPoint:
currentPath.addCurve(to: element.points[2], control1: element.points[0], control2: element.points[1])
case .closeSubpath:
currentPath.closeSubpath()
#unknown default:
fatalError()
}
}
self.cgPath = currentPath
}
func firstPoint() -> CGPoint? {
var firstPoint: CGPoint? = nil
var index = -1
self.cgPath.applyWithBlock { block in
index += 1
let element = block.pointee
if index == 0 {
if element.type == .moveToPoint || element.type == .addLineToPoint {
firstPoint = element.points[0]
} else if element.type == .addQuadCurveToPoint {
firstPoint = element.points[1]
} else if element.type == .addCurveToPoint {
firstPoint = element.points[2]
}
}
}
return firstPoint
}
func lastPoint() -> CGPoint? {
var lastPoint: CGPoint? = nil
var index = -1
self.reversing().cgPath.applyWithBlock { block in
index += 1
let element = block.pointee
if index == 0 {
if element.type == .moveToPoint || element.type == .addLineToPoint {
lastPoint = element.points[0]
} else if element.type == .addQuadCurveToPoint {
lastPoint = element.points[1]
} else if element.type == .addCurveToPoint {
lastPoint = element.points[2]
}
}
}
return lastPoint
}
}

Answer 2

well if its only an esthetically problem...just set the first point of the 2nd bezier curve as the last point of the 1st..and so on..
if its not i don't think there is a way to merge 2 or more bezier paths cuz ...well..they are bezier and it wont look right if you do
read more about bezier curves
bezier curves and see why it wont work