OpenFont (Apache FOP Core 2.11 API)
Date: 2025-04-24

org.apache.fop.fonts.truetype

## Class OpenFont

- java.lang.Object
- - org.apache.fop.fonts.truetype.OpenFont

- Direct Known Subclasses:
    OTFFile, TTFFile

      public abstract class OpenFont
      extends Object

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and Description
    --- | ---
    `static class` | `OpenFont.PostScriptVersion` Version of the PostScript table (post) contained in this font.

  - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected OTFAdvancedTypographicTableReader` | `advancedTableReader`
    `protected boolean` | `cid`
    `protected Map<OFTableName,OFDirTabEntry>` | `dirTabs` Table directory
    `protected String` | `embedFontName`
    `protected Set<String>` | `familyNames`
    `protected FontFileReader` | `fontFile` The FontFileReader used to read this TrueType font.
    `protected String` | `fullName`
    `protected long` | `lastLoca` Offset to last loca
    `protected int` | `locaFormat`
    `protected org.apache.commons.logging.Log` | `log` logging instance
    `protected OFMtxEntry[]` | `mtxTab` Contains glyph data
    `protected int` | `nhmtx`
    `protected String` | `notice`
    `protected int` | `numberOfGlyphs`
    `protected String` | `postScriptName`
    `protected String` | `subFamilyName`
    `protected Map<Integer,SVGGlyphData>` | `svgs`
    `static boolean` | `TRACE_ENABLED` Set to true to get even more debug output than with level DEBUG
    `protected List<org.apache.fop.fonts.truetype.OpenFont.UnicodeMapping>` | `unicodeMappings`
    `protected boolean` | `useAdvanced`
    `protected boolean` | `useKerning`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `OpenFont()`
    `OpenFont(boolean useKerning, boolean useAdvanced)` Constructor

  - ### Method Summary

    All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected boolean` | `checkTTC(String tag, String name)` Check if this is a TrueType collection and that the given name exists in the collection.
    `int` | `convertTTFUnit2PDFUnit(int n)` Convert from truetype unit to pdf unit based on the unitsPerEm field in the "head" table
    `protected void` | `createCMaps()`
    `protected void` | `determineAscDesc()` Determines the right source for the ascender and descender values.
    `Map<Integer,Map<Integer,Integer>>` | `getAnsiKerning()` Returns the ANSI kerning table.
    `int[]` | `getBBox(int glyphIndex)` Returns an array (xMin, yMin, xMax, yMax) for a glyph.
    `int[]` | `getBBoxRaw()` Returns the original bounding box values from the HEAD table
    `Rectangle[]` | `getBoundingBoxes()`
    `int` | `getCapHeight()` Returns the CapHeight attribute of the font.
    `String` | `getCharSetName()` Returns the name of the character set used.
    `int` | `getCharWidth(int idx)` Returns the width of a given character.
    `int` | `getCharWidthRaw(int idx)` Returns the width of a given character in raw units
    `List<CMapSegment>` | `getCMaps()` Returns this font's character to glyph mapping.
    `String` | `getCopyrightNotice()`
    `OFDirTabEntry` | `getDirectoryEntry(OFTableName name)` Obtain directory table entry.
    `String` | `getEmbedFontName()`
    `Set<String>` | `getFamilyNames()` Returns the font family names of the font.
    `short` | `getFirstChar()` Returns the index of the first character.
    `int` | `getFlags()` Returns the Flags attribute of the font.
    `int[]` | `getFontBBox()`
    `String` | `getFullName()` Returns the full name of the font.
    `GlyphDefinitionTable` | `getGDEF()` Returns the GDEF table or null if none present.
    `GlyphPositioningTable` | `getGPOS()` Returns the GPOS table or null if none present.
    `GlyphSubstitutionTable` | `getGSUB()` Returns the GSUB table or null if none present.
    `String` | `getItalicAngle()` Returns the ItalicAngle attribute of the font.
    `Map<Integer,Map<Integer,Integer>>` | `getKerning()` Returns the kerning table.
    `short` | `getLastChar()` Returns the index of the last character, but this is for WinAnsiEncoding only, so the last char is < 256.
    `int` | `getLowerCaseAscent()` Returns the LowerCaseAscent attribute of the font.
    `int` | `getLowerCaseDescent()` Returns the LowerCaseDescent attribute of the font.
    `List<OFMtxEntry>` | `getMtx()`
    `protected void` | `getNumGlyphs()` Read the number of glyphs from the "maxp" table
    `protected int` | `getPadSize(int currentPosition)` Returns the number of bytes necessary to pad the currentPosition so that a table begins on a 4-byte boundary.
    `String` | `getPostScriptName()` Returns the PostScript name of the font.
    `String` | `getStemV()` Returns the StemV attribute of the font.
    `int` | `getStrikeoutPosition()`
    `int` | `getStrikeoutThickness()`
    `String` | `getSubFamilyName()` Returns the font sub family name of the font.
    `List<String>` | `getTTCnames(FontFileReader in)` Return TTC font names
    `int` | `getUnderlinePosition()`
    `int` | `getUnderlineThickness()`
    `int` | `getWeightClass()` Returns the weight class of this font.
    `int[]` | `getWidths()` Returns an array of character widths.
    `int` | `getXHeight()` Returns the XHeight attribute of the font.
    `protected void` | `guessVerticalMetricsFromGlyphBBox()`
    `protected void` | `handleCharacterSpacing(FontFileReader in)`
    `boolean` | `hasAdvancedTable()` Determine if advanced (typographic) table is present.
    `protected void` | `initAnsiWidths()` initialize the ansiWidths array (for winAnsiEncoding) and fill with the missingwidth
    `protected abstract void` | `initializeFont(FontFileReader in)`
    `boolean` | `isCFF()` Indicates whether or not the font is an OpenType CFF font (rather than a TrueType font).
    `boolean` | `isEmbeddable()` Indicates if the font may be embedded.
    `static void` | `main(String[] args)` Static main method to get info about a TrueType font.
    `void` | `printStuff()` Dumps a few informational values to System.out.
    `protected boolean` | `readCMAP()` Read the cmap table, return false if the table is not present or only unsupported tables are present.
    `protected void` | `readDirTabs()` Read Table Directory from the current position in the FontFileReader and fill the global HashMap dirTabs with the table name (String) as key and a TTFDirTabEntry as value.
    `void` | `readFont(FontFileReader in, String header)` Reads the font using a FontFileReader.
    `void` | `readFont(FontFileReader in, String header, MultiByteFont mbfont)` Reads a font.
    `boolean` | `readFont(FontFileReader in, String header, String name)` Read the font data.
    `protected void` | `readFontHeader()` Read the "head" table, this reads the bounding box and sets the upem (unitsPerEM) variable
    `protected void` | `readHorizontalHeader()` Read the "hhea" table to find the ascender and descender and size of "hmtx" table, as a fixed size font might have only one width.
    `protected void` | `readHorizontalMetrics()` Read "hmtx" table and put the horizontal metrics in the mtxTab array.
    `protected void` | `readKerning()` Read the kerning table, create a table for both CIDs and winAnsiEncoding.
    `protected abstract void` | `readName()`
    `protected void` | `readOS2()` Read the "OS/2" table
    `protected boolean` | `readPCLT()` Read the "PCLT" table to find xHeight and capHeight.
    `protected void` | `readPostScript()` Read the "post" table containing the PostScript names of the glyphs.
    `boolean` | `seekTab(FontFileReader in, OFTableName tableName, long offset)` Position inputstream to position indicated in the dirtab offset + offset
    `void` | `stream(TTFOutputStream ttfOut)` Streams a font.
    `protected abstract void` | `updateBBoxAndOffset()`

    - ### Methods inherited from class java.lang.Object

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

- - ### Field Detail

    - #### fontFile

          protected FontFileReader fontFile

      The FontFileReader used to read this TrueType font.

    - #### TRACE_ENABLED

          public static final boolean TRACE_ENABLED

      Set to true to get even more debug output than with level DEBUG
      See Also:
        Constant Field Values

    - #### useKerning

          protected boolean useKerning

    - #### dirTabs

          protected Map<OFTableName,OFDirTabEntry> dirTabs

      Table directory

    - #### unicodeMappings

          protected List<org.apache.fop.fonts.truetype.OpenFont.UnicodeMapping> unicodeMappings

    - #### nhmtx

          protected int nhmtx

    - #### locaFormat

          protected int locaFormat

    - #### lastLoca

          protected long lastLoca

      Offset to last loca

    - #### numberOfGlyphs

          protected int numberOfGlyphs

    - #### mtxTab

          protected OFMtxEntry[] mtxTab

      Contains glyph data

    - #### postScriptName

          protected String postScriptName

    - #### fullName

          protected String fullName

    - #### embedFontName

          protected String embedFontName

    - #### notice

          protected String notice

    - #### familyNames

          protected final Set<String> familyNames

    - #### subFamilyName

          protected String subFamilyName

    - #### cid

          protected boolean cid

    - #### svgs

          protected Map<Integer,SVGGlyphData> svgs

    - #### useAdvanced

          protected boolean useAdvanced

    - #### advancedTableReader

          protected OTFAdvancedTypographicTableReader advancedTableReader

    - #### log

          protected org.apache.commons.logging.Log log

      logging instance

  - ### Constructor Detail

    - #### OpenFont

          public OpenFont()

    - #### OpenFont

          public OpenFont(boolean useKerning,
                          boolean useAdvanced)

      Constructor
      Parameters:
        `useKerning` - true if kerning data should be loaded
        `useAdvanced` - true if advanced typographic tables should be loaded

  - ### Method Detail

    - #### getDirectoryEntry

          public OFDirTabEntry getDirectoryEntry(OFTableName name)

      Obtain directory table entry.
      Parameters:
        `name` - (tag) of entry
      Returns:
        a directory table entry or null if none found

    - #### seekTab

          public boolean seekTab(FontFileReader in,
                                 OFTableName tableName,
                                 long offset)
                          throws IOException

      Position inputstream to position indicated in the dirtab offset + offset
      Parameters:
        `in` - font file reader
        `tableName` - (tag) of table
        `offset` - from start of table
      Returns:
        true if seek succeeded
      Throws:
        `IOException` - if I/O exception occurs during seek

    - #### convertTTFUnit2PDFUnit

          public int convertTTFUnit2PDFUnit(int n)

      Convert from truetype unit to pdf unit based on the unitsPerEm field in the "head" table
      Parameters:
        `n` - truetype unit
      Returns:
        pdf unit

    - #### readCMAP

          protected boolean readCMAP()
                              throws IOException

      Read the cmap table, return false if the table is not present or only unsupported tables are present. Currently only unicode cmaps are supported. Set the unicodeIndex in the TTFMtxEntries and fills in the cmaps vector.
      Throws:
        `IOException`
      See Also:
        TrueType-Reference-Manual

    - #### getMtx

          public List<OFMtxEntry> getMtx()

      Returns:
        mmtx data

    - #### readFont

          public void readFont(FontFileReader in,
                               String header)
                        throws IOException

      Reads the font using a FontFileReader.
      Parameters:
        `in` - The FontFileReader to use
      Throws:
        `IOException` - In case of an I/O problem

    - #### initAnsiWidths

          protected void initAnsiWidths()

      initialize the ansiWidths array (for winAnsiEncoding) and fill with the missingwidth

    - #### readFont

          public boolean readFont(FontFileReader in,
                                  String header,
                                  String name)
                           throws IOException

      Read the font data. If the fontfile is a TrueType Collection (.ttc file) the name of the font to read data for must be supplied, else the name is ignored.
      Parameters:
        `in` - The FontFileReader to use
        `name` - The name of the font
      Returns:
        boolean Returns true if the font is valid
      Throws:
        `IOException` - In case of an I/O problem

    - #### readFont

          public void readFont(FontFileReader in,
                               String header,
                               MultiByteFont mbfont)
                        throws IOException

      Reads a font.
      Parameters:
        `in` - FontFileReader to read from
      Throws:
        `IOException` - in case of an I/O problem

    - #### updateBBoxAndOffset

          protected abstract void updateBBoxAndOffset()
                                               throws IOException

      Throws:
        `IOException`

    - #### readName

          protected abstract void readName()
                                    throws IOException

      Throws:
        `IOException`

    - #### initializeFont

          protected abstract void initializeFont(FontFileReader in)
                                          throws IOException

      Throws:
        `IOException`

    - #### handleCharacterSpacing

          protected void handleCharacterSpacing(FontFileReader in)
                                         throws IOException

      Throws:
        `IOException`

    - #### createCMaps

          protected void createCMaps()

    - #### getPostScriptName

          public String getPostScriptName()

      Returns the PostScript name of the font.
      Returns:
        String The PostScript name

    - #### getFamilyNames

          public Set<String> getFamilyNames()

      Returns the font family names of the font.
      Returns:
        Set The family names (a Set of Strings)

    - #### getSubFamilyName

          public String getSubFamilyName()

      Returns the font sub family name of the font.
      Returns:
        String The sub family name

    - #### getFullName

          public String getFullName()

      Returns the full name of the font.
      Returns:
        String The full name

    - #### getCharSetName

          public String getCharSetName()

      Returns the name of the character set used.
      Returns:
        String The caracter set

    - #### getCapHeight

          public int getCapHeight()

      Returns the CapHeight attribute of the font.
      Returns:
        int The CapHeight

    - #### getXHeight

          public int getXHeight()

      Returns the XHeight attribute of the font.
      Returns:
        int The XHeight

    - #### getPadSize

          protected int getPadSize(int currentPosition)

      Returns the number of bytes necessary to pad the currentPosition so that a table begins on a 4-byte boundary.
      Parameters:
        `currentPosition` - the position to pad.
      Returns:
        int the number of bytes to pad.

    - #### getFlags

          public int getFlags()

      Returns the Flags attribute of the font.
      Returns:
        int The Flags

    - #### getWeightClass

          public int getWeightClass()

      Returns the weight class of this font. Valid values are 100, 200....,800, 900.
      Returns:
        the weight class value (or 0 if there was no OS/2 table in the font)

    - #### getStemV

          public String getStemV()

      Returns the StemV attribute of the font.
      Returns:
        String The StemV

    - #### getItalicAngle

          public String getItalicAngle()

      Returns the ItalicAngle attribute of the font.
      Returns:
        String The ItalicAngle

    - #### getFontBBox

          public int[] getFontBBox()

      Returns:
        int[] The font bbox

    - #### getBBoxRaw

          public int[] getBBoxRaw()

      Returns the original bounding box values from the HEAD table
      Returns:
        An array of bounding box values

    - #### getLowerCaseAscent

          public int getLowerCaseAscent()

      Returns the LowerCaseAscent attribute of the font.
      Returns:
        int The LowerCaseAscent

    - #### getLowerCaseDescent

          public int getLowerCaseDescent()

      Returns the LowerCaseDescent attribute of the font.
      Returns:
        int The LowerCaseDescent

    - #### getLastChar

          public short getLastChar()

      Returns the index of the last character, but this is for WinAnsiEncoding only, so the last char is < 256.
      Returns:
        short Index of the last character (<256)

    - #### getFirstChar

          public short getFirstChar()

      Returns the index of the first character.
      Returns:
        short Index of the first character

    - #### getWidths

          public int[] getWidths()

      Returns an array of character widths.
      Returns:
        int[] The character widths

    - #### getBoundingBoxes

          public Rectangle[] getBoundingBoxes()

    - #### getBBox

          public int[] getBBox(int glyphIndex)

      Returns an array (xMin, yMin, xMax, yMax) for a glyph.
      Parameters:
        `glyphIndex` - the index of the glyph
      Returns:
        int[] Array defining bounding box.

    - #### getCharWidth

          public int getCharWidth(int idx)

      Returns the width of a given character.
      Parameters:
        `idx` - Index of the character
      Returns:
        int Standard width

    - #### getCharWidthRaw

          public int getCharWidthRaw(int idx)

      Returns the width of a given character in raw units
      Parameters:
        `idx` - Index of the character
      Returns:
        int Width in it's raw form stored in the font

    - #### getKerning

          public Map<Integer,Map<Integer,Integer>> getKerning()

      Returns the kerning table.
      Returns:
        Map The kerning table

    - #### getAnsiKerning

          public Map<Integer,Map<Integer,Integer>> getAnsiKerning()

      Returns the ANSI kerning table.
      Returns:
        Map The ANSI kerning table

    - #### getUnderlinePosition

          public int getUnderlinePosition()

    - #### getUnderlineThickness

          public int getUnderlineThickness()

    - #### getStrikeoutPosition

          public int getStrikeoutPosition()

    - #### getStrikeoutThickness

          public int getStrikeoutThickness()

    - #### isEmbeddable

          public boolean isEmbeddable()

      Indicates if the font may be embedded.
      Returns:
        boolean True if it may be embedded

    - #### isCFF

          public boolean isCFF()

      Indicates whether or not the font is an OpenType CFF font (rather than a TrueType font).
      Returns:
        true if the font is in OpenType CFF format.

    - #### readDirTabs

          protected void readDirTabs()
                              throws IOException

      Read Table Directory from the current position in the FontFileReader and fill the global HashMap dirTabs with the table name (String) as key and a TTFDirTabEntry as value.
      Throws:
        `IOException` - in case of an I/O problem

    - #### readFontHeader

          protected void readFontHeader()
                                 throws IOException

      Read the "head" table, this reads the bounding box and sets the upem (unitsPerEM) variable
      Throws:
        `IOException` - in case of an I/O problem

    - #### getNumGlyphs

          protected void getNumGlyphs()
                               throws IOException

      Read the number of glyphs from the "maxp" table
      Throws:
        `IOException` - in case of an I/O problem

    - #### readHorizontalHeader

          protected void readHorizontalHeader()
                                       throws IOException

      Read the "hhea" table to find the ascender and descender and size of "hmtx" table, as a fixed size font might have only one width.
      Throws:
        `IOException` - in case of an I/O problem

    - #### readHorizontalMetrics

          protected void readHorizontalMetrics()
                                        throws IOException

      Read "hmtx" table and put the horizontal metrics in the mtxTab array. If the number of metrics is less than the number of glyphs (eg fixed size fonts), extend the mtxTab array and fill in the missing widths
      Throws:
        `IOException` - in case of an I/O problem

    - #### readPostScript

          protected void readPostScript()
                                 throws IOException

      Read the "post" table containing the PostScript names of the glyphs.
      Throws:
        `IOException`

    - #### readOS2

          protected void readOS2()
                          throws IOException

      Read the "OS/2" table
      Throws:
        `IOException`

    - #### readPCLT

          protected boolean readPCLT()
                              throws IOException

      Read the "PCLT" table to find xHeight and capHeight.
      Throws:
        `IOException` - In case of a I/O problem

    - #### determineAscDesc

          protected void determineAscDesc()

      Determines the right source for the ascender and descender values. The problem here is that the interpretation of these values is not the same for every font. There doesn't seem to be a uniform definition of an ascender and a descender. In some fonts the hhea values are defined after the Apple interpretation, but not in every font. The same problem is in the OS/2 table. FOP needs the ascender and descender to determine the baseline so we need values which add up more or less to the "em box". However, due to accent modifiers a character can grow beyond the em box.

    - #### guessVerticalMetricsFromGlyphBBox

          protected void guessVerticalMetricsFromGlyphBBox()

    - #### readKerning

          protected void readKerning()
                              throws IOException

      Read the kerning table, create a table for both CIDs and winAnsiEncoding.
      Throws:
        `IOException` - In case of a I/O problem

    - #### stream

          public void stream(TTFOutputStream ttfOut)
                      throws IOException

      Streams a font.
      Parameters:
        `ttfOut` - The interface for streaming TrueType tables.
      Throws:
        `IOException` - file write error

    - #### getCMaps

          public List<CMapSegment> getCMaps()

      Returns this font's character to glyph mapping.
      Returns:
        the font's cmap

    - #### checkTTC

          protected final boolean checkTTC(String tag,
                                           String name)
                                    throws IOException

      Check if this is a TrueType collection and that the given name exists in the collection. If it does, set offset in fontfile to the beginning of the Table Directory for that font.
      Parameters:
        `name` - The name to check
      Returns:
        True if not collection or font name present, false otherwise
      Throws:
        `IOException` - In case of an I/O problem

    - #### getTTCnames

          public final List<String> getTTCnames(FontFileReader in)
                                         throws IOException

      Return TTC font names
      Parameters:
        `in` - FontFileReader to read from
      Returns:
        True if not collection or font name present, false otherwise
      Throws:
        `IOException` - In case of an I/O problem

    - #### printStuff

          public void printStuff()

      Dumps a few informational values to System.out.

    - #### hasAdvancedTable

          public boolean hasAdvancedTable()

      Determine if advanced (typographic) table is present.
      Returns:
        true if advanced (typographic) table is present

    - #### getGDEF

          public GlyphDefinitionTable getGDEF()

      Returns the GDEF table or null if none present.
      Returns:
        the GDEF table

    - #### getGSUB

          public GlyphSubstitutionTable getGSUB()

      Returns the GSUB table or null if none present.
      Returns:
        the GSUB table

    - #### getGPOS

          public GlyphPositioningTable getGPOS()

      Returns the GPOS table or null if none present.
      Returns:
        the GPOS table

    - #### main

          public static void main(String[] args)

      Static main method to get info about a TrueType font.
      Parameters:
        `args` - The command line arguments

    - #### getEmbedFontName

          public String getEmbedFontName()

    - #### getCopyrightNotice

          public String getCopyrightNotice()

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