truetypefont.java

java itext java itext java itext

/*
 * $Id: TrueTypeFont.java,v 1.10 2001/12/10 13:53:22 blowagie Exp $
 * $Name:  $
 *
 * Copyright 2001 by Paulo Soares
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or any
 * later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Library general Public License for more
 * details.
 *
 * You should have received a copy of the GNU Library General Public License along
 * with this library; if not, write to the Free Foundation, Inc., 59 Temple Place,
 * Suite 330, Boston, MA 02111-1307 USA.
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 *
 * ir-arch Bruno Lowagie,
 * Adolf Baeyensstraat 121
 * 9040 Sint-Amandsberg
 * BELGIUM
 * tel. [phone]
 * [e-mail]
 *
 */

package com.lowagie.text.pdf;

import java.io.*;
import java.util.HashMap;
import java.util.Iterator;
import com.lowagie.text.DocumentException;
/** Reads a Truetype font
 *
 * @author Paulo Soares ([e-mail])
 */
class TrueTypeFont extends BaseFont {
    /** Contains the location of the several tables. The key is the name of
     * the table and the value is an <CODE>int[2]</CODE> where position 0
     * is the offset from the start of the file and position 1 is the length
     * of the table.
     */
    protected HashMap tables;
    /** The file in use.
     */
    protected RandomAccessFile rf;
    /** The file name.
     */
    protected String fileName;
    
    /** The offset from the start of the file to the table directory.
     * It is 0 for TTF and may vary for TTC depending on the chosen font.
     */    
    protected int directoryOffset;
    /** The index for the TTC font. It is an empty <CODE>String</CODE> for a
     * TTF file.
     */    
    protected String ttcIndex;
    /** The style modifier */
    protected String style = "";
    /** The content of table 'head'.
     */
    protected FontHeader head = new FontHeader();
    /** The content of table 'hhea'.
     */
    protected HorizontalHeader hhea = new HorizontalHeader();
    /** The content of table 'OS/2'.
     */
    protected WindowsMetrics os_2 = new WindowsMetrics();
    /** The width of the glyphs. This is essentially the content of table
     * 'hmtx' normalized to 1000 units.
     */
    protected int GlyphWidths[];
    /** The map containing the code information for the table 'cmap', encoding 1.0.
     * The key is the code and the value is an <CODE>int[2]</CODE> where position 0
     * is the glyph number and position 1 is the glyph width normalized to 1000
     * units.
     */
    protected HashMap cmap10;
    /** The map containing the code information for the table 'cmap', encoding 3.1
     * in Unicode.
     * <P>
     * The key is the code and the value is an <CODE>int</CODE>[2] where position 0
     * is the glyph number and position 1 is the glyph width normalized to 1000
     * units.
     */
    protected HashMap cmap31;
    /** The map containig the kerning information. It represents the content of
     * table 'kern'. The key is an <CODE>Integer</CODE> where the top 16 bits
     * are the Unicode for the first character and the lower 16 bits are the
     * Unicode for the second character. The value is the amount of kerning in
     * normalized 1000 units as an <CODE>Integer</CODE>. This value is usually negative.
     */
    protected HashMap kerning;
    /** The font name. this name is usually extracted from the table 'name' with
     * the 'Name ID' 6.
     */
    protected String fontName;
    /** The italic angle. It is usually extracted from the 'post' table or in it's
     * absence with the code:
     * <P>
     * <PRE>
     * -Math.atan2(hhea.caretSlopeRun, hhea.caretSlopeRise) * 180 / Math.PI
     * </PRE>
     */
    protected double italicAngle;
    /** <CODE>true</CODE> if all the glyphs have the same width.
     */
    protected boolean isFixedPitch = false;
    
    /** The components of table 'head'.
     */
    protected class FontHeader {
        /** A variable. */
        int flags;
        /** A variable. */
        int unitsPerEm;
        /** A variable. */
        short xMin;
        /** A variable. */
        short yMin;
        /** A variable. */
        short xMax;
        /** A variable. */
        short yMax;
        /** A variable. */
        int macStyle;
    }
    
    /** The components of table 'hhea'.
     */
    protected class HorizontalHeader {
        /** A variable. */
        short Ascender;
        /** A variable. */
        short Descender;
        /** A variable. */
        short LineGap;
        /** A variable. */
        int advanceWidthMax;
        /** A variable. */
        short minLeftSideBearing;
        /** A variable. */
        short minRightSideBearing;
        /** A variable. */
        short xMaxExtent;
        /** A variable. */
        short caretSlopeRise;
        /** A variable. */
        short caretSlopeRun;
        /** A variable. */
        int numberOfHMetrics;
    }
    
    /** The components of table 'OS/2'.
     */
    protected class WindowsMetrics {
        /** A variable. */
        short xAvgCharWidth;
        /** A variable. */
        int usWeightClass;
        /** A variable. */
        int usWidthClass;
        /** A variable. */
        short fsType;
        /** A variable. */
        short ySubscriptXSize;
        /** A variable. */
        short ySubscriptYSize;
        /** A variable. */
        short ySubscriptXOffset;
        /** A variable. */
        short ySubscriptYOffset;
        /** A variable. */
        short ySuperscriptXSize;
        /** A variable. */
        short ySuperscriptYSize;
        /** A variable. */
        short ySuperscriptXOffset;
        /** A variable. */
        short ySuperscriptYOffset;
        /** A variable. */
        short yStrikeoutSize;
        /** A variable. */
        short yStrikeoutPosition;
        /** A variable. */
        short sFamilyClass;
        /** A variable. */
        byte panose[] = new byte[10];
        /** A variable. */
        byte achVendID[] = new byte[4];
        /** A variable. */
        int fsSelection;
        /** A variable. */
        int usFirstCharIndex;
        /** A variable. */
        int usLastCharIndex;
        /** A variable. */
        short sTypoAscender;
        /** A variable. */
        short sTypoDescender;
        /** A variable. */
        short sTypoLineGap;
        /** A variable. */
        int usWinAscent;
        /** A variable. */
        int usWinDescent;
        /** A variable. */
        int sCapHeight;
    }
    
    /** This constructor is present to allow extending the class.
     */
    protected TrueTypeFont() {
    }
    
    /** Creates a new TrueType font.
     * @param ttFile the location of the font on file. The file must end in '.ttf' or
     * '.ttc' but can have modifiers after the name
     * @param enc the encoding to be applied to this font
     * @param emb true if the font is to be embedded in the PDF
     * @throws DocumentException the font is invalid
     * @throws IOException the font file could not be read
     */
    TrueTypeFont(String ttFile, String enc, boolean emb) throws DocumentException, IOException {
        String nameBase = getBaseName(ttFile);
        String ttcName = getTTCName(nameBase);
        if (nameBase.length() < ttFile.length()) {
            style = ttFile.substring(nameBase.length());
        }
        encoding = enc;
        embedded = emb;
        fileName = ttcName;
        fontType = FONT_TYPE_TT;
        ttcIndex = "";
        if (ttcName.length() < nameBase.length())
            ttcIndex = nameBase.substring(ttcName.length() + 1);
        if (fileName.toLowerCase().endsWith(".ttf") || fileName.toLowerCase().endsWith(".ttc")) {
            process();
        }
        else
            throw new DocumentException(fileName + style + " is not a TTF or TTC font file.");
        try {
            " ".getBytes(enc); // check if the encoding exists
            createEncoding();
        }
        catch (UnsupportedEncodingException e) {
            throw new DocumentException(e.getMessage());
        }
    }
    
    /** Gets the name from a composed TTC file name.
     * If I have for input "myfont.ttc,2" the return will
     * be "myfont.ttc".
     * @param name the full name
     * @return the simple file name
     */    
    protected static String getTTCName(String name) {
        int idx = name.toLowerCase().indexOf(".ttc,");
        if (idx < 0)
            return name;
        else
            return name.substring(0, idx + 4);
    }
    
    
    /**
     * Reads the tables 'head', 'hhea', 'OS/2' and 'post' filling several variables.
     * @throws DocumentException the font is invalid
     * @throws IOException the font file could not be read
     */
    void fillTables() throws DocumentException, IOException {
        int table_location[];
        table_location = (int[])tables.get("head");
        if (table_location == null)
            throw new DocumentException("Table 'head' does not exist in " + fileName + style);
        rf.seek(table_location[0] + 16);
        head.flags = rf.readUnsignedShort();
        head.unitsPerEm = rf.readUnsignedShort();
        rf.skipBytes(16);
        head.xMin = rf.readShort();
        head.yMin = rf.readShort();
        head.xMax = rf.readShort();
        head.yMax = rf.readShort();
        head.macStyle = rf.readUnsignedShort();
        
        table_location = (int[])tables.get("hhea");
        if (table_location == null)
            throw new DocumentException("Table 'hhea' does not exist " + fileName + style);
        rf.seek(table_location[0] + 4);
        hhea.Ascender = rf.readShort();
        hhea.Descender = rf.readShort();
        hhea.LineGap = rf.readShort();
        hhea.advanceWidthMax = rf.readUnsignedShort();
        hhea.minLeftSideBearing = rf.readShort();
        hhea.minRightSideBearing = rf.readShort();
        hhea.xMaxExtent = rf.readShort();
        hhea.caretSlopeRise = rf.readShort();
        hhea.caretSlopeRun = rf.readShort();
        rf.skipBytes(12);
        hhea.numberOfHMetrics = rf.readUnsignedShort();