flash.display3D

# Context3DBlendFactor - AS3

Package | flash.display3D
Class | public final class Context3DBlendFactor
Inheritance | Context3DBlendFactor Object

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

Defines the values to use for specifying the source and destination blend factors.

A blend factor represents a particular four-value vector that is multiplied with the source or destination color in the blending formula. The blending formula is:

`result = source * sourceFactor + destination * destinationFactor`

In the formuls, the source color is the output color of the pixel shader program. The destination color is the color that currently exists in the color buffer, as set by previous clear and draw operations.

For example, if the source color is (.6, .6, .6, .4) and the source blend factor is `Context3DBlendFactor.ONE_MINUS_SOURCE_ALPHA`, then the source part of the blending equation is calculated as:

`(.6, .6, .6, .4) * (1-0.4, 1-0.4, 1-0.4, 1-0.4) = (.36, .36, .36, .24)`

The final calculation is clamped to the range [0,1].

Examples

The following examples demonstrate the blending math using source color = (.6,.4,.2,.4), destination color = (.8,.8,.8,.5), and various blend factors.

Purpose | Source factor | Destination factor | Blend formula | Result
--- | --- | --- | --- | ---
No blending | ONE | ZERO | (.6,.4,.2,.4) * ( 1, 1, 1, 1) + (.8,.8,.8,.5) * ( 0, 0, 0, 0) | ( .6, .4, .2, .4)
Alpha | SOURCE_ALPHA | ONE_MINUS_SOURCE_ALPHA | (.6,.4,.2,.4) * (.4,.4,.4,.4) + (.8,.8,.8,.5) * (.6,.6,.6,.6) | (.72,.64,.56,.46)
Additive | ONE | ONE | (.6,.4,.2,.4) * ( 1, 1, 1, 1) + (.8,.8,.8,.5) * ( 1, 1, 1, 1) | ( 1, 1, 1, .9)
Multiply | DESTINATION_COLOR | ZERO | (.6,.4,.2,.4) * (.8,.8,.8,.5) + (.8,.8,.8,.5) * ( 0, 0, 0, 0) | (.48,.32,.16, .2)
Screen | ONE | ONE_MINUS_SOURCE_COLOR | (.6,.4,.2,.4) * ( 1, 1, 1, 1) + (.8,.8,.8,.5) * (.4,.6,.8,.6) | (.92,.88,.68, .7)

Note that not all combinations of blend factors are useful and that you can sometimes achieve the same effect in different ways.

Related API Elements

Context3D.setBlendFactors()

Public Properties
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| Property | Defined By
--- | --- | ---
|  | constructor : Object A reference to the class object or constructor function for a given object instance. | Object

Public Methods
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| Method | Defined By
--- | --- | ---
|  | 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

Public Constants

| Constant | Defined By
--- | --- | ---
|  | DESTINATION_ALPHA : String = "destinationAlpha" [static] The blend factor is (Da,Da,Da,Da), where Da is the alpha component of the fragment color computed by the pixel program. | Context3DBlendFactor
|  | DESTINATION_COLOR : String = "destinationColor" [static] The blend factor is (Dr,Dg,Db,Da), where Dr/g/b/a is the corresponding component of the current color in the color buffer. | Context3DBlendFactor
|  | ONE : String = "one" [static] The blend factor is (1,1,1,1). | Context3DBlendFactor
|  | ONE_MINUS_DESTINATION_ALPHA : String = "oneMinusDestinationAlpha" [static] The blend factor is (1-Da,1-Da,1-Da,1-Da), where Da is the alpha component of the current color in the color buffer. | Context3DBlendFactor
|  | ONE_MINUS_DESTINATION_COLOR : String = "oneMinusDestinationColor" [static] The blend factor is (1-Dr,1-Dg,1-Db,1-Da), where Dr/g/b/a is the corresponding component of the current color in the color buffer. | Context3DBlendFactor
|  | ONE_MINUS_SOURCE_ALPHA : String = "oneMinusSourceAlpha" [static] The blend factor is (1-Sa,1-Sa,1-Sa,1-Sa), where Sa is the alpha component of the fragment color computed by the pixel program. | Context3DBlendFactor
|  | ONE_MINUS_SOURCE_COLOR : String = "oneMinusSourceColor" [static] The blend factor is (1-Sr,1-Sg,1-Sb,1-Sa), where Sr/g/b/a is the corresponding component of the fragment color computed by the pixel program. | Context3DBlendFactor
|  | SOURCE_ALPHA : String = "sourceAlpha" [static] The blend factor is (Sa,Sa,Sa,Sa), where Sa is the alpha component of the fragment color computed by the pixel program. | Context3DBlendFactor
|  | SOURCE_COLOR : String = "sourceColor" [static] The blend factor is (Sr,Sg,Sb,Sa), where Sr/g/b/a is the corresponding component of the fragment color computed by the pixel program. | Context3DBlendFactor
|  | ZERO : String = "zero" [static] The blend factor is (0,0,0,0). | Context3DBlendFactor

Constant Detail

### DESTINATION_ALPHA

Constant

`public static const DESTINATION_ALPHA:String = "destinationAlpha"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(Da,Da,Da,Da)`, where `Da` is the alpha component of the fragment color computed by the pixel program.

### DESTINATION_COLOR

Constant

`public static const DESTINATION_COLOR:String = "destinationColor"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(Dr,Dg,Db,Da)`, where `Dr/g/b/a` is the corresponding component of the current color in the color buffer.

### ONE

Constant

`public static const ONE:String = "one"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(1,1,1,1)`.

### ONE_MINUS_DESTINATION_ALPHA

Constant

`public static const ONE_MINUS_DESTINATION_ALPHA:String = "oneMinusDestinationAlpha"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(1-Da,1-Da,1-Da,1-Da)`, where `Da` is the alpha component of the current color in the color buffer.

### ONE_MINUS_DESTINATION_COLOR

Constant

`public static const ONE_MINUS_DESTINATION_COLOR:String = "oneMinusDestinationColor"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(1-Dr,1-Dg,1-Db,1-Da)`, where `Dr/g/b/a` is the corresponding component of the current color in the color buffer.

### ONE_MINUS_SOURCE_ALPHA

Constant

`public static const ONE_MINUS_SOURCE_ALPHA:String = "oneMinusSourceAlpha"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(1-Sa,1-Sa,1-Sa,1-Sa)`, where `Sa` is the alpha component of the fragment color computed by the pixel program.

### ONE_MINUS_SOURCE_COLOR

Constant

`public static const ONE_MINUS_SOURCE_COLOR:String = "oneMinusSourceColor"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(1-Sr,1-Sg,1-Sb,1-Sa)`, where `Sr/g/b/a` is the corresponding component of the fragment color computed by the pixel program.

### SOURCE_ALPHA

Constant

`public static const SOURCE_ALPHA:String = "sourceAlpha"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(Sa,Sa,Sa,Sa)`, where `Sa` is the alpha component of the fragment color computed by the pixel program.

### SOURCE_COLOR

Constant

`public static const SOURCE_COLOR:String = "sourceColor"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(Sr,Sg,Sb,Sa)`, where `Sr/g/b/a` is the corresponding component of the fragment color computed by the pixel program.

### ZERO

Constant

`public static const ZERO:String = "zero"`

Language Version: | ActionScript 3.0

Runtime Versions: | Flash Player 11, AIR 3

The blend factor is `(0,0,0,0)`.

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Mon Apr 10 2017, 12:28 PM -07:00