I wanted to add lipstick like effect on lips using CGMutable path. Detecting face landmarks using vision kit. Landmark.outer lips fill the whole lips, even opened mouth. i wanted to apply on the lips area only.

I have tried to play VNFaceLandmarkRegion2D.normalized path point but unable to achieve the result. Below is the code snippet.

let landmarkPath = CGMutablePath()
    let landmarkPathPoints = eye.normalizedPoints
        .map({ eyePoint in
            CGPoint(
                x: eyePoint.y * faceBoundingBox.height + faceBoundingBox.origin.x,
                y: eyePoint.x * faceBoundingBox.width + faceBoundingBox.origin.y
            )
        })

    
  landmarkPath.addLines(between: landmarkPathPoints)
    landmarkPath.closeSubpath()
    let landmarkLayer = CAShapeLayer()
    landmarkLayer.path = landmarkPath
    landmarkLayer.fillColor = nil
    landmarkLayer.strokeColor = UIColor.green.cgColor
    
    self.faceLayers.append(landmarkLayer)
    self.view.layer.addSublayer(landmarkLayer)