CGContextAddCurve

CGContextAddCurve is a function in the Core Graphics framework of Apple's operating systems that allows developers to add a cubic Bézier curve to a graphics path. This function is used within a drawing context to define the shape of curves that will be rendered.

The function takes several parameters: the drawing context itself, and then eight floating-point values representing the coordinates of four points. The first two coordinates (x1, y1) define the start point of the curve. The next four coordinates (x2, y2, x3, y3) define two control points. The final two coordinates (x4, y4) define the end point of the curve. The curve's shape is determined by how the control points influence the trajectory from the start point to the end point.

Cubic Bézier curves are a common way to represent smooth, flowing lines in computer graphics. They offer more control over the curve's shape compared to quadratic Bézier curves, as they have two control points instead of one. After calling CGContextAddCurve, the curve becomes part of the current path. This path can then be stroked (drawn with a line) or filled (colored in) using other Core Graphics functions. This function is essential for creating custom shapes, drawing charts, and designing user interface elements with curved borders or graphics.