PDFTron pdfnet-node

Class: Function

PDFNet. Function

new Function()

Although PDF is not a programming language it provides several types of function object that represent parameterized classes of functions, including mathematical formulas and sampled representations with arbitrary resolution. Functions are used in various ways in PDF, including device-dependent rasterization information for high-quality printing (halftone spot functions and transfer functions), color transform functions for certain color spaces, and specification of colors as a function of position for smooth shadings. Functions in PDF represent static, self-contained numerical transformations.

PDF::Function represents a single, flat interface around all PDF function types.

Extends

Members

<static> Type

Type:
  • number
Properties:
Name Type Description
e_sampled number
e_exponential number
e_stitching number
e_postscript number

Methods

<static> create( [funct_dict])

Create a PDF::Function object from an existing SDF function dictionary. If funct_dict is null, a non valid Function object is created.
Parameters:
Name Type Argument Description
funct_dict PDFNet.Obj <optional>
Returns:
A promise that resolves to an object of type: "PDFNet.Function"
Type
Promise.<PDFNet.Function>

destroy()

Destructor
Inherited From:
Returns:
Type
Promise.<void>

eval(inval, outval)

Parameters:
Name Type Description
inval number
outval number
Returns:
Type
Promise.<void>

getInputCardinality()

Returns:
A promise that resolves to the number of input components required by the function
Type
Promise.<number>

getOutputCardinality()

Returns:
A promise that resolves to the number of output components returned by the function
Type
Promise.<number>

getSDFObj()

Returns:
A promise that resolves to the underlying SDF/Cos object
Type
Promise.<PDFNet.Obj>

getType()

Returns:
A promise that resolves to the function type
Type
Promise.<number>
Example
Return value enum:
<pre>
PDFNet.Function.Type = {
	e_sampled : 0
	e_exponential : 2
	e_stitching : 3
	e_postscript : 4
}
</pre>

takeOwnership()

Take the ownership of this object, so that PDFNet.runWithCleanup won't destroy this object.
Inherited From:
Returns:
Type
void