Instance Method

addQuadCurveToPoint:controlPoint:

Appends a quadratic Bézier curve to the receiver’s path.

Declaration

- (void)addQuadCurveToPoint:(CGPoint)endPoint controlPoint:(CGPoint)controlPoint;

Parameters

endPoint

The end point of the curve.

controlPoint

The control point of the curve.

Discussion

This method appends a quadratic Bézier curve from the current point to the end point specified by the endPoint parameter. The relationships between the current point, control point, and end point are what defines the actual curve. Figure 1 shows some examples of quadratic curves and the approximate curve shape based on some sample points. The exact curvature of the segment involves a complex mathematical relationship between the points and is well documented online.

Figure 1

Quadratic curve examples

You must set the path’s current point (using the moveToPoint: method or through the previous creation of a line or curve segment) before you call this method. If the path is empty, this method does nothing. After adding the curve segment, this method updates the current point to the value in point.

See Also

Constructing a Path

- moveToPoint:

Moves the receiver’s current point to the specified location.

- addLineToPoint:

Appends a straight line to the receiver’s path.

- addArcWithCenter:radius:startAngle:endAngle:clockwise:

Appends an arc to the receiver’s path.

- addCurveToPoint:controlPoint1:controlPoint2:

Appends a cubic Bézier curve to the receiver’s path.

- closePath

Closes the most recently added subpath.

- removeAllPoints

Removes all points from the receiver, effectively deleting all subpaths.

- appendPath:

Appends the contents of the specified path object to the receiver’s path.

CGPath

The Core Graphics representation of the path.

- CGPath

The Core Graphics representation of the path.

currentPoint

The current point in the graphics path.