Turtle Graphics绘图Drawing功能

应用介绍

Turtle Graphics绘图Drawing功能，TurtleBezierPath 是 UIBezierPath 的子类，用于实现了 Turtle Graphics 的绘图方式。效果图1，小编绘制了一个简单的圆形；效果图2，小编通过一系列命令的组成绘制了较为复杂的组合图形。 Turtle Graphics 是什么呢？小编稍微调研了一下，Turtle Graphics是一种制图方式。基本元素就是一个箭头（用于控制画线方向），然后通过一系列的（编程）命令，比如直走、向左、向右、左弧形、右弧形等等来绘制一系列复杂的矢量图。具体情况Wiki：http://en.wikipedia.org/wiki/Turtle_graphics 。 TurtleBezierPath is a UIBezierPath subclass for Turtle Graphics: a simple, intuitive drawing system developed my 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.