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15. Graphics and Animations > 15.5. Drawing Lines
Retrieve the handle to your graphics context and then use the
CGContextMoveToPoint
and the CGContextAddLineToPoint functions to draw
your line.
When we talk about drawing shapes in iOS or OS X, we are implicitly talking about paths. What are paths, you may ask? A path is constructed from one or more series of points drawn on a screen. There is a big difference between paths and lines. A path can contain many lines, but a line cannot contain many paths. Think of paths as series of points—it’s as simple as that.
Lines have to be drawn using paths. Specify the start and end points, and then ask Core Graphics to fill that path for you. Core Graphics realizes that you have created a line on that path, and will paint that path for you using the color that you specified (see Recipe 15.3).
