Distance At Best Angle

DistanceAtBestAngle.swift

public static func distanceAtBestAngle(points: [StrokePoint], strokeTemplate: [StrokePoint], var fromAngle: Double, var toAngle: Double, threshold: Double) -> Double {
	var x1 = StrokeConsts.Phi * fromAngle + (1.0 - StrokeConsts.Phi) * toAngle
	var f1 = StrokePoint.distanceAtAngle(points, strokeTemplate: strokeTemplate, radians: x1)
		
	var x2 = (1.0 - StrokeConsts.Phi) * fromAngle + StrokeConsts.Phi * toAngle
	var f2 = StrokePoint.distanceAtAngle(points, strokeTemplate: strokeTemplate, radians: x2)
		
	while ( abs(toAngle-fromAngle) > threshold ) {
		if f1 < f2 {
			toAngle = x2
			x2 = x1
			f2 = f1
			x1 = StrokeConsts.Phi * fromAngle + (1.0 - StrokeConsts.Phi) * toAngle
			f1 = StrokePoint.distanceAtAngle(points, strokeTemplate: strokeTemplate, radians: x1)
		} else {
			fromAngle = x1
			x1 = x2
			f1 = f2
			x2 = (1.0 - StrokeConsts.Phi) * fromAngle + StrokeConsts.Phi * toAngle
			f2 = StrokePoint.distanceAtAngle(points, strokeTemplate: strokeTemplate, radians: x2)
		}
	}
	return min(f1,f2)
}