NSBezierPathからSVGのpath要素d属性の値を作る

NSBezierPathの'elementAtIndex:associatedPoints:'メソッドについてのあれこれ．

 NSBezierPath *path= ...;
 NSMutableString *dValue= [NSMutableString string];

 int j, cj= [path elementCount];
 for(j= 0; j<cj; j++) {
  NSPoint points[3];
  NSBezierPathElement e= [path elementAtIndex:j associatedPoints:points];
  if (e == NSMoveToBezierPathElement) {
   NSPoint p= points[0];
   [dValue appendFormat:@"M %.4f,%.4f", p.x, p.y];
  } 
  else if (e == NSLineToBezierPathElement) {
   NSPoint p= points[0];
   [dValue appendFormat:@" L%.4f,%.4f", p.x, p.y];
  }
  else if (e == NSCurveToBezierPathElement) {
   NSPoint c1= points[0];
   NSPoint c2= points[1];
   NSPoint p= points[2];
   [dValue appendFormat:@" C%.4f,%.4f,%.4f,%.4f,%.4f,%.4f",  c1.x, c1.y, c2.x, c2.y, p.x, p.y];
  }
  else if (e == NSClosePathBezierPathElement) {
   [dValue appendFormat:@" Z"];
   break; //グリフなどのように複数パスがある場合はこれいらない．
  }
 }