Package org.openpdf.renderer.function

Class FunctionType4

java.lang.Object

org.openpdf.renderer.function.PDFFunction

org.openpdf.renderer.function.FunctionType4

public class FunctionType4
extends PDFFunction

A PostScript function is represented as a stream containing code written in a small subset of the PostScript language. This reference is taken from the (3200-1:2008:7.10.5)

http://www.adobe.com/devnet/acrobat/pdfs/adobe_supplement_iso32000.pdf

Field Summary

Fields

Modifier and Type	Field	Description
private Stack<Object>	stack	the stack of operations.
private List<String>	tokens	the list of tokens and sub-expressions.

Fields inherited from class org.openpdf.renderer.function.PDFFunction

TYPE_0, TYPE_2, TYPE_3, TYPE_4

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	FunctionType4()	Creates a new instance of FunctionType4

Method Summary

Modifier and Type	Method	Description
private void	assertResultIsCorrect(float[] outputs, int outputOffset)
protected void	doFunction(float[] inputs, int inputOffset, float[] outputs, int outputOffset)	Map from m input values to n output values.
protected void	parse(PDFObject obj)	Read the function information from a PDF Object
private void	prepareInitialStack(float[] inputs, int inputOffset)	Put all input values on the initial stack.
private void	prepareResult(float[] outputs, int outputOffset)

Methods inherited from class org.openpdf.renderer.function.PDFFunction

calculate, calculate, getDomain, getFunction, getNumInputs, getNumOutputs, getRange, getType, interpolate, setDomain, setRange

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

tokens

private List<String> tokens

the list of tokens and sub-expressions.

stack

private Stack<Object> stack

the stack of operations. The stack contents should all be Comparable.

Constructor Details

FunctionType4

protected FunctionType4()

Creates a new instance of FunctionType4

Method Details

parse

protected void parse(PDFObject obj)
              throws IOException

Read the function information from a PDF Object

Specified by:

parse in class PDFFunction

Throws:

IOException

doFunction

protected void doFunction(float[] inputs,
 int inputOffset,
 float[] outputs,
 int outputOffset)

Map from m input values to n output values. The number of inputs m must be exactly one half the size of the domain. The number of outputs should match one half the size of the range.

Specified by:

doFunction in class PDFFunction

Parameters:

inputs - an array of m input values

inputOffset - the offset into the input array to read from

outputs - an array of size >= n which will be filled with the output values

outputOffset - the offset into the output array to write to

prepareResult

private void prepareResult(float[] outputs,
 int outputOffset)

Parameters:

outputs -

outputOffset -

prepareInitialStack

private void prepareInitialStack(float[] inputs,
 int inputOffset)

Put all input values on the initial stack. All values are pushed as Double because we calculate internally with double.

Parameters:

inputs -

inputOffset -

assertResultIsCorrect

private void assertResultIsCorrect(float[] outputs,
 int outputOffset)

Parameters:

outputs -

outputOffset -