---
title: CGPathAddRelativeArc
framework: coregraphics
role: symbol
role_heading: Function
path: coregraphics/cgpathaddrelativearc
---

# CGPathAddRelativeArc

Appends an arc to a mutable graphics path, possibly preceded by a straight line segment.

## Declaration

```occ
extern void CGPathAddRelativeArc(CGMutablePathRef path, const CGAffineTransform *matrix, CGFloat x, CGFloat y, CGFloat radius, CGFloat startAngle, CGFloat delta);
```

## Parameters

- `path`: The mutable graphics path to change.
- `matrix`: A pointer to an affine transformation matrix, or NULL if no transformation is needed. If specified, Core Graphics applies the transformation to the arc before it is added to the path.
- `x`: The x-coordinate of the center point of the arc.
- `y`: The y-coordinate of the center point of the arc.
- `radius`: The radius of the arc.
- `startAngle`: The angle (in radians) that determines the starting point of the arc, measured from the x-axis in the current user space.
- `delta`: The distance the arc should travel (in radians). A positive value indicates a counter-clockwise arc in the current user space.

## Discussion

Discussion The angle to the second endpoint of the arc is calculated by adding the delta to the start angle.

## See Also

### Constructing a Graphics Path

- [CGPathMoveToPoint](coregraphics/cgpathmovetopoint.md)
- [CGPathAddLineToPoint](coregraphics/cgpathaddlinetopoint.md)
- [CGPathAddLines](coregraphics/cgpathaddlines.md)
- [CGPathAddRect](coregraphics/cgpathaddrect.md)
- [CGPathAddRects](coregraphics/cgpathaddrects.md)
- [CGPathAddEllipseInRect](coregraphics/cgpathaddellipseinrect.md)
- [CGPathAddRoundedRect](coregraphics/cgpathaddroundedrect.md)
- [CGPathAddArc](coregraphics/cgpathaddarc.md)
- [CGPathAddArcToPoint](coregraphics/cgpathaddarctopoint.md)
- [CGPathAddCurveToPoint](coregraphics/cgpathaddcurvetopoint.md)
- [CGPathAddQuadCurveToPoint](coregraphics/cgpathaddquadcurvetopoint.md)
- [CGPathAddPath](coregraphics/cgpathaddpath.md)
- [closeSubpath()](coregraphics/cgmutablepath/closesubpath().md)