Having position problem in Core Text animation - ios

Question

I'm trying to convert following (link) swift code in objective c.
https://stackoverflow.com/a/49100870/797196
CTFontRef helveticaBold = CTFontCreateWithName( CFSTR("Helvetica-Bold"), 60.0, NULL);
NSString* unicodeString =#"Window Title";
CGColorRef color = [UIColor blueColor].CGColor;
NSNumber* underline = [NSNumber numberWithInt:
kCTUnderlineStyleSingle|kCTUnderlinePatternDot];
NSDictionary* attributesDict = [NSDictionary dictionaryWithObjectsAndKeys:
(__bridge id)helveticaBold, (NSString*)kCTFontAttributeName,
color, (NSString*)kCTForegroundColorAttributeName,
underline, (NSString*)kCTUnderlineStyleAttributeName, nil];
NSAttributedString* stringToDraw = [[NSAttributedString alloc]
initWithString:unicodeString
attributes:attributesDict];
CGMutablePathRef letters = CGPathCreateMutable();
// CTFontRef font = CTFontCreateWithName((__bridge CFStringRef)#"Avenir",20,nil);
CTLineRef lines = CTLineCreateWithAttributedString((CFAttributedStringRef)stringToDraw);
CFArrayRef runArray = CTLineGetGlyphRuns(lines);
CAShapeLayer *pathLayer = [CAShapeLayer layer];
for (int i = 0; i < CFArrayGetCount(runArray); i++) {
CTRunRef run = CFArrayGetValueAtIndex(runArray, i);
CFDictionaryRef dictRef = CTRunGetAttributes(run);
NSDictionary *dict = (__bridge NSDictionary*)dictRef;
CTFontRef runFont = (__bridge CTFontRef)(dict[(NSString*)kCTFontAttributeName]);
for (int runGlyphIndex=0; runGlyphIndex<CTRunGetGlyphCount(run); runGlyphIndex++) {
CGGlyph glyph;
CGPoint position = CGPointZero;
CTRunGetGlyphs(run, CFRangeMake(runGlyphIndex, 1), &glyph);
CTRunGetPositions(run, CFRangeMake(runGlyphIndex, 1), &position);
CGPathRef letter = CTFontCreatePathForGlyph(runFont, glyph, nil);
CGAffineTransform t = CGAffineTransformMakeTranslation(position.x, position.y);
CGPathAddPath(letters, &t, letter);
CAShapeLayer *pathL = [CAShapeLayer layer];
// pathLayer.frame = _pathLayerView.bounds;
CGRect rect = CGPathGetBoundingBox(letter);
rect.origin = position;
pathL.frame = rect;
pathL.geometryFlipped = true;
pathL.path = letter;
pathL.strokeColor = UIColor.blueColor.CGColor;
pathL.fillColor = UIColor.redColor.CGColor;
pathL.lineWidth = 4.0;
pathL.lineJoin = kCALineJoinBevel;
CABasicAnimation *stroke = [CABasicAnimation animationWithKeyPath:#"strokeEnd"];
stroke.fromValue = #(0.0);
stroke.duration = 3.0f;
stroke.repeatCount = 0;
[pathL addAnimation:stroke forKey:nil];
[pathLayer addSublayer:pathL];
}
}
[_pathLayerView.layer addSublayer:pathLayer];
But the problem is letters alignment is not in required position. "i","n","o" letters y position starts from the top. & its obvious, because I didn't use the position of the letters.
I find out the positions of the letters using CTRunGetPositions, but I dont know how to use it or where to use it.