ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Using the drawing API
Point A single location in a coordinate space. In the 2-d coordinate system used in ActionScript, a point is defined by
its location along the x axis and the y axis (the point’s coordinates).
Quadratic Bézier curve A type of curve defined by a particular mathematical formula. In this type of curve, the shape
of the curve is calculated based on the positions of the anchor points (the end points of the curve) and a control point
that defines the amount and direction of the curve.
Scale The size of an object relative to its original size. When used as a verb, to scale an object means to change its size
by stretching or shrinking the object.
Stroke The outline portion of a shape that has a line filled in with color, or the lines of an un-filled shape.
Translate To change a point’s coordinates from one coordinate space to another.
X axis The horizontal axis in the 2-d coordinate system used in ActionScript.
Y axis The vertical axis in the 2-d coordinate system used in ActionScript.
The Graphics class
Flash Player 9 and later, Adobe AIR 1.0 and later
Each Shape, Sprite, and MovieClip object has a graphics property, which is an instance of the Graphics class. The
Graphics class includes properties and methods for drawing lines, fills, and shapes. If you want a display object to use
solely as a canvas for drawing content, you can use a Shape instance. A Shape instance will perform better than other
display objects for drawing, because it doesn’t have the overhead of the additional functionality in the Sprite and
MovieClip classes. If you want a display object on which you can draw graphical content and also want that object to
contain other display objects, you can use a Sprite instance. For more information on determining which display object
to use for various tasks, see “Choosing a DisplayObject subclass” on page 172.
Drawing lines and curves
Flash Player 9 and later, Adobe AIR 1.0 and later
All drawing that you do with a Graphics instance is based on basic drawing with lines and curves. Consequently, all
ActionScript drawing must be performed using the same series of steps:
Define line and fill styles
Set the initial drawing position
Draw lines, curves, and shapes (optionally moving the drawing point)
If necessary, finish creating a fill
Last updated 6/6/2012
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