ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with Pixel Bender shaders
4 Save the Pixel Bender bytecode file in the same directory as the Flash document. The file’s name should match the
name specified in the example description.
The ActionScript part of each example is written as a class file. To test the example in Flash Professional:
1 Create an empty Flash document and save it to your computer.
2 Create a new ActionScript file and save it in the same directory as the Flash document. The file’s name should match
the name of the class in the code listing. For instance, if the code listing defines a class named MyApplication, use
the name MyApplication.as to save the ActionScript file.
3 Copy the code listing into the ActionScript file and save the file.
4 In the Flash document, click a blank part of the Stage or work space to activate the document Property inspector.
5 In the Property inspector, in the Document Class field, enter the name of the ActionScript class you copied from
the text.
6 Run the program using Control > Test Movie
You will see the results of the example in the preview window.
These techniques for testing example code listings are explained in more detail in “How to Use ActionScript Examples”
on page 1085.
Loading or embedding a shader
Flash Player 10 and later, Adobe AIR 1.5 and later
The first step in using a Pixel Bender shader in ActionScript is to get access to the shader in your ActionScript code.
Because a shader is created using the Adobe Pixel Bender Toolkit, and written in the Pixel Bender language, it cannot
be directly accessed in ActionScript. Instead, you create an instance of the Shader class that represents the Pixel Bender
shader to ActionScript. The Shader object allows you to find out information about the shader, such as whether it
expects parameters or input image values. You pass the Shader object to other objects to actually use the shader. For
example, to use the shader as a filter you assign the Shader object to a ShaderFilter object’s shader property.
Alternatively, to use the shader as a drawing fill, you pass the Shader object as an argument to the
Graphics.beginShaderFill() method.
Your ActionScript code can access a shader created by Adobe Pixel Bender Toolkit (a .pbj file) in two ways:
Loaded at run time: the shader file can be loaded as an external asset using a URLLoader object. This technique is
like loading an external asset such as a text file. The following example demonstrates loading a shader bytecode file
at run time and linking it to a Shader instance:
Last updated 6/6/2012
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