org.extex.font.format.xtf.tables.gps
Class XtfGPOSSingleTable.SingleTableFormat2

java.lang.Object
  org.extex.font.format.xtf.tables.gps.XtfLookupTable
      org.extex.font.format.xtf.tables.gps.XtfGPOSSingleTable
          org.extex.font.format.xtf.tables.gps.XtfGPOSSingleTable.SingleTableFormat2

All Implemented Interfaces:

XMLWriterConvertible

Enclosing class:

XtfGPOSSingleTable

public static class XtfGPOSSingleTable.SingleTableFormat2
extends XtfGPOSSingleTable
implements XMLWriterConvertible

Single Adjustment Positioning: Format 2

A SinglePosFormat2 subtable provides an array of ValueRecords that contains one positioning value for each glyph in the Coverage table. This format is more flexible than Format 1, but it requires more space in the font file.

For example, assume that the Cyrillic script will be used in left-justified text. For all glyphs, Format 2 could define position adjustments for left side bearings to align the left edges of the paragraphs. To achieve this, the Coverage table would list every glyph in the script, and the SinglePosFormat2 subtable would define a ValueRecord for each covered glyph. Correspondingly, each ValueRecord would specify an XPlacement adjustment value for the left side bearing.

Note: All ValueRecords defined in a SinglePos subtable must have the same ValueFormat. In this example, if XPlacement is the only value that a ValueRecord needs to optically align the glyphs, then XPlacement will be the only value specified in the ValueFormat of the subtable.

As in Format 1, the Format 2 subtable consists of a format identifier (PosFormat), an offset to a Coverage table that defines the glyphs to be adjusted by the positioning values (Coverage), and the format identifier (ValueFormat) that describes the amount and kinds of data in the ValueRecords. In addition, the Format 2 subtable includes:

A count of the ValueRecords (ValueCount). One ValueRecord is defined for each glyph in the Coverage table.

An array of ValueRecords that specify positioning values (Value). Because the array follows the Coverage Index order, the first ValueRecord applies to the first glyph listed in the Coverage table, and so on.

SinglePosFormat2 subtable: Array of positioning values

Value	Type	Description
uint16	PosFormat	Format identifier-format = 2
Offset	Coverage	Offset to Coverage table-from beginning of SinglePos subtable
uint16	ValueFormat	Defines the types of data in the ValueRecord
uint16	ValueCount	Number of ValueRecords
ValueRecord	Value [ValueCount]	Array of ValueRecords-positioning values applied to glyphs

Nested Class Summary

Nested classes/interfaces inherited from class org.extex.font.format.xtf.tables.gps.XtfGPOSSingleTable

XtfGPOSSingleTable.SingleTableFormat1, XtfGPOSSingleTable.SingleTableFormat2

Field Summary

Fields inherited from class org.extex.font.format.xtf.tables.gps.XtfGPOSSingleTable

coverage

Fields inherited from class org.extex.font.format.xtf.tables.gps.XtfLookupTable

count

Method Summary

int	getValueFormat() Getter for valueFormat.
ValueRecord	getValueRecord(int glyph) Returns the ValueRecord for the glyph.
ValueRecord[]	getValueRecordArray() Getter for valueRecordArray.
void	writeXML(XMLStreamWriter writer) Write the data to a XMLStreamWriter.

Methods inherited from class org.extex.font.format.xtf.tables.gps.XtfGPOSSingleTable

getCoverage, newInstance

Methods inherited from class org.extex.font.format.xtf.tables.gps.XtfLookupTable

getCount, getFormat, getXtfGlyph

Methods inherited from class java.lang.Object

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

Method Detail

getValueFormat

public int getValueFormat()

Getter for valueFormat.

Returns:

the valueFormat

getValueRecord

public ValueRecord getValueRecord(int glyph)

Returns the ValueRecord for the glyph.

Specified by:

getValueRecord in class XtfGPOSSingleTable

Parameters:

glyph - The glyph.

Returns:

Returns the ValueRecord for the glyph or null, if not found.

See Also:

XtfGPOSSingleTable.getValueRecord(int)

getValueRecordArray

public ValueRecord[] getValueRecordArray()

Getter for valueRecordArray.

Returns:

the valueRecordArray

writeXML

public void writeXML(XMLStreamWriter writer)
              throws java.io.IOException

Write the data to a XMLStreamWriter.

Specified by:

writeXML in interface XMLWriterConvertible

Parameters:

writer - the XML-Writer

Throws:

java.io.IOException - if an IO-error occurs.

See Also:

XMLWriterConvertible.writeXML(org.extex.util.xml.XMLStreamWriter)