TurtleBezierPath
TurtleBezierPath is a UIBezierPath subclass for Turtle Graphics: a simple, intuitive drawing system developed by Seymour Papert for the Logo programming language.
The Turtle is a drawing cursor that follows the commands: home, turn, forward, leftArc, rightArc, up and down. As the Turtle moves, it draws a path in its wake. Many shapes are much easier to draw this way.
Demo app
The app requires iOS 7 and allows you to explore Turtle Graphics drawing with simple controls. It's fun too!
Installation
Simply add TurtleBezierPath.swift to your project, or add it as a Cocoapod named TurtleBezierPath.
Both NSCoding and NSCopying are fully supported.
var bearing: CGFloat // The compass bearing of the Turtle in degrees
- 0 - North
- 90 - East
- 180 - South
- 270 - West
var penUp: Bool // When YES the Turtle will move but not draw
func boundsWithStroke() -> CGRect // The bounds rect of the path including the stroke width
func home() // Move the Turtle to (0, 0) and set the bearing to 0 degrees
func forward(_ distance: CGFloat) // Move the Turtle forward distance points
func turn(_ angle: CGFloat) // Add angle degrees to the Turtle's bearing
func leftArc(_ radius: CGFloat, turn angle: CGFloat) // Move the Turtle angle degrees in an anticlockwise arc of radius points
func rightArc(_ radius: CGFloat, turn angle: CGFloat) // Move the Turtle angle degrees in a clockwise arc of radius points
func down() // Move the pen down
func up() // Move the pen up
func centerInBounds(_ bounds: CGRect) // Transform the path so that the home position is in the centre of the bounds