flash.display.ShaderData - Adobe® Flex® 4 Language Reference (Flex 4)

Package	flash.display
Class	public final dynamic class ShaderData
Inheritance	ShaderData Object

Language Version:

ActionScript 3.0

Runtime Versions:

Flash Player 10, AIR 1.5

A ShaderData object contains properties representing any parameters and inputs for a shader kernel, as well as properties containing any metadata specified for the shader.

These properties are added to the ShaderData object when it is created. The properties' names match the names specified in the shader's source code. The data type of each property varies according to what aspect of the shader the property represents. The properties that represent shader parameters are ShaderParameter instances, the properties that represent input images are ShaderInput instances, and the properties that represent shader metadata are instances of the ActionScript class corresponding to their data type (for example, a String instance for textual metadata and a uint for uint metadata).

For example, consider this shader, which is defined with one input image (src), two parameters (size and radius), and three metadata values (nameSpace, version, and description):

     <languageVersion : 1.0;>
     
     kernel DoNothing
     <
         namespace: "Adobe::Example";
         vendor: "Adobe examples";
         version: 1;
         description: "A shader that does nothing, but does it well.";
     >
     {
         input image4 src;
     
         output pixel4 dst;
         
         parameter float2 size
         <
             description: "The size of the image to which the kernel is applied";
             minValue: float2(0.0, 0.0);
             maxValue: float2(100.0, 100.0);
             defaultValue: float2(50.0, 50.0);
         >;
         
         parameter float radius
         <
             description: "The radius of the effect";
             minValue: 0.0;
             maxValue: 50.0;
             defaultValue: 25.0;
         >;
     
         void evaluatePixel()
         {
             float2 one = (radius / radius) ∗ (size / size);
             dst = sampleNearest(src, outCoord());
         }
     }

If you create a Shader instance by loading the byte code for this shader, the ShaderData instance in its data property contains these properties:

Property	Data type	Value
name	String	"DoNothing"
nameSpace	String	"Adobe::Example"
version	String	"1"
description	String	"A shader that does nothing, but does it well."
src	ShaderInput	[A ShaderInput instance]
size	ShaderParameter	[A ShaderParameter instance, with properties for the parameter metadata]
radius	ShaderParameter	[A ShaderParameter instance, with properties for the parameter metadata]

Note that any input image or parameter that is defined in the shader source code but not used in the shader's evaluatePixel() function is removed when the shader is compiled to byte code. In that case, there is no corresponding ShaderInput or ShaderParameter instance added as a property of the ShaderData instance.

Generally, developer code does not create a ShaderData instance. A ShaderData instance containing data, parameters, and inputs for a shader is available as the Shader instance's data property.

View the examples

	Property	Defined By
		constructor : Object A reference to the class object or constructor function for a given object instance.	Object
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object

	Method	Defined By
		ShaderData(byteCode:ByteArray) Creates a ShaderData instance.	ShaderData
		hasOwnProperty(name:String):Boolean Indicates whether an object has a specified property defined.	Object
		isPrototypeOf(theClass:Object):Boolean Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.	Object
		propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable.	Object
		setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations.	Object
		toLocaleString():String Returns the string representation of this object, formatted according to locale-specific conventions.	Object
		toString():String Returns the string representation of the specified object.	Object
		valueOf():Object Returns the primitive value of the specified object.	Object

ShaderData

()

Constructor

public function ShaderData(byteCode:ByteArray)

Language Version:

ActionScript 3.0

Runtime Versions:

Flash Player 10, AIR 1.5

Creates a ShaderData instance. Generally, developer code does not call the ShaderData constructor directly. A ShaderData instance containing data, parameters, and inputs for a Shader instance is accessed using its data property.

Parameters

byteCode:ByteArray — The shader's byte code.

See also

flash.display.Shader.data

Examples ( How to use this example )

ShaderDataExample.1.as

The following example loads a shader and enumerates the ShaderData instance in its data property to display the input, parameters, and metadata properties of the shader.

Note that this example assumes there's a shader bytecode file named "donothing.pbj" in the same directory as the output directory for the application.


//
// Source code for the shader:
//
<languageVersion : 1.0;>

kernel DoNothing
<
    namespace: "Adobe::Example";
    vendor: "Adobe examples";
    version: 1;
    description: "A shader that does nothing, but does it well.";
>
{
    input image4 src;
    
    output pixel4 dst;
    
    parameter float2 size
    <
        description: "The size of the image to which the shader is applied";
        minValue: float2(0.0, 0.0);
        maxValue: float2(100.0, 100.0);
        defaultValue: float2(50.0, 50.0);
    >;
    
    parameter float radius
    <
        description: "The radius of the effect";
        minValue: float(0.0);
        maxValue: float(50.0);
        defaultValue: float(25.0);
    >;

    void evaluatePixel()
    {
        float2 one = (radius / radius) * (size / size);
        dst = sampleNearest(src, outCoord());
    }
}

//
// ActionScript source code:
//
package {
    import flash.display.Shader;
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.net.URLLoader;
    import flash.net.URLLoaderDataFormat;
    import flash.net.URLRequest;

    public class ShaderDataExample extends Sprite {
        
        private var loader:URLLoader;
        
        public function ShaderDataExample() {
            loader = new URLLoader();
            loader.dataFormat = URLLoaderDataFormat.BINARY;
            loader.addEventListener(Event.COMPLETE, loadCompleteHandler);
            loader.load(new URLRequest("donothing.pbj"));
        }
        
        private function loadCompleteHandler(event:Event):void {
            var shader:Shader = new Shader();
            shader.byteCode = loader.data;
            
            for (var p:String in shader.data) {
                trace(p, ":", shader.data[p]);
                for (var d:String in shader.data[p]) {
                    trace("\t", d, ":", shader.data[p][d]);
                }
            }
        }
    }
}