in Source/Charts/Utils/ChartUtils.swift [293:297]
func drawMultilineText(_ text: String, at point: CGPoint, constrainedTo size: CGSize, anchor: CGPoint, angleRadians: CGFloat, attributes: [NSAttributedString.Key : Any]?)
{
let rect = text.boundingRect(with: size, options: .usesLineFragmentOrigin, attributes: attributes, context: nil)
drawMultilineText(text, at: point, constrainedTo: size, anchor: anchor, knownTextSize: rect.size, angleRadians: angleRadians, attributes: attributes)
}