org.extex.font.format.xtf.tables.gps
Class OtfTableGSUB

java.lang.Object
  org.extex.font.format.xtf.tables.AbstractXtfTable
      org.extex.font.format.xtf.tables.gps.AbstractXtfSFLTable
          org.extex.font.format.xtf.tables.gps.OtfTableGSUB

All Implemented Interfaces:

LookupTableFactory, XtfGlyphName, XtfTable, XMLWriterConvertible

public class OtfTableGSUB
extends AbstractXtfSFLTable
implements XtfTable, LookupTableFactory, XMLWriterConvertible

Glyph substitution (GSUB).

To access GSUB information, clients should use the following procedure:

1. Locate the current script in the GSUB ScriptList table.
2. If the language system is known, search the script for the correct LangSys table; otherwise, use the script's default language system (DefaultLangSys table).
3. The LangSys table provides index numbers into the GSUB FeatureList table to access a required feature and a number of additional features.
4. Inspect the FeatureTag of each feature, and select the features to apply to an input glyph string. Each feature provides an array of index numbers into the GSUB LookupList table.
5. Assemble all lookups from the set of chosen features, and apply the lookups in the order given in the LookupList table.

Version:

$Revision: 7274 $

Author:

Michael Niedermair

Field Summary

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

featureList, lookupList, scriptList

Constructor Summary

OtfTableGSUB(XtfTableMap tablemap, XtfTableDirectory.Entry de, RandomAccessR rar)
Create a new object

Method Summary

java.lang.String	getShortcut() Returns the table shortcut.
int	getType() Get the table type, as a table directory value.
java.lang.String	lookupType(int type) Returns the name of the lookup type (The start index is 1!).
XtfLookupTable	read(RandomAccessR rar, int posOffset, int type, int offset, XtfGlyphName xtfGlyph) Read the LookupTable or null, if not found.

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

findLangSys, findLookup, findScript, getFeatureList, getFeatureTag, getLookupList, getScriptList, writeXML

Methods inherited from class org.extex.font.format.xtf.tables.AbstractXtfTable

getGlyphName, getInitOrder, getTableMap, init, writeStartElement

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.extex.font.format.xtf.tables.XtfTable

getInitOrder, getTableMap, init

Methods inherited from interface org.extex.util.xml.XMLWriterConvertible

writeXML

Constructor Detail

OtfTableGSUB

public OtfTableGSUB(XtfTableMap tablemap,
                    XtfTableDirectory.Entry de,
                    RandomAccessR rar)
             throws java.io.IOException

Create a new object

Parameters:

tablemap - the table map

de - directory entry

rar - input

Throws:

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

Method Detail

getShortcut

public java.lang.String getShortcut()

Returns the table shortcut.

Specified by:

getShortcut in interface XtfTable

Returns:

Returns the table shortcut.

See Also:

XtfTable.getShortcut()

getType

public int getType()

Get the table type, as a table directory value.

Specified by:

getType in interface XtfTable

Returns:

Returns the table type

lookupType

public java.lang.String lookupType(int type)

Returns the name of the lookup type (The start index is 1!).

Specified by:

lookupType in interface LookupTableFactory

Parameters:

type - The type.

Returns:

Returns the name of the lookup type.

See Also:

LookupTableFactory.lookupType(int)

read

public XtfLookupTable read(RandomAccessR rar,
                           int posOffset,
                           int type,
                           int offset,
                           XtfGlyphName xtfGlyph)
                    throws java.io.IOException

Read the LookupTable or null, if not found.

Type:

1 - Single - Replace one glyph with one glyph

2 - Multiple - Replace one glyph with more than one glyph

3 - Alternate - Replace one glyph with one of many glyphs

4 - Ligature - Replace multiple glyphs with one glyph

5 - Context - Replace one or more glyphs in context

6 - Chaining - Context Replace one or more glyphs in chained context

Specified by:

read in interface LookupTableFactory

Parameters:

rar - The input.

posOffset - The offset of the pos table (GPOS, GSUB).

type - The table type.

offset - The offset.

xtfGlyph - The glyph name.

Returns:

Returns the table.

Throws:

java.io.IOException - if a io-error occurred.

See Also:

LookupTableFactory.read(org.extex.util.file.random.RandomAccessR, int, int, int, org.extex.font.format.xtf.tables.XtfGlyphName)