ttfcmaptable.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 216 行

// Copyright 2001, FreeHEP.
package org.jnode.awt.font.truetype;

import java.io.IOException;

/**
 * CMAP Table.
 *
 *  @author Simon Fischer
 *  @version $Id: TTFCMapTable.java,v 1.1 2003/11/25 11:51:38 epr Exp $
 */
public class TTFCMapTable extends TTFTable {

	private int version;
	private EncodingTable encodingTable[];

	public int getNrEncodingTables() {
		return encodingTable.length;
	}

	public EncodingTable getEncodingTable(int index) {
		return encodingTable[index];
	}

	public class EncodingTable {
		private int platformID;
		private int encodingID;
		private long offset;
		private int format;
		private int length;
		private int encTblVersion;
		private TableFormat tableFormat;

		public void readHeader() throws IOException {
			platformID = ttf.readUShort();
			encodingID = ttf.readUShort();
			offset = ttf.readULong();
		}

		public void readBody() throws IOException {
			ttf.seek(offset);
			format = ttf.readUShort();
			length = ttf.readUShort();
			encTblVersion = ttf.readUShort();
			switch (format) {
				case 0 :
					tableFormat = new TableFormat0();
					break;
				case 4 :
					tableFormat = new TableFormat4();
					break;
				case 6 :
					tableFormat = new TableFormat6();
					break;
				case 2 :
					break;
				default :
					System.err.println("Illegal value for encoding table format: " + format);
					break;
			}
			if (tableFormat != null)
				tableFormat.read();
		}

		public String toString() {
			String str =
				"[encoding] PID:" + platformID + " EID:" + encodingID + " format:" + format + " v" + encTblVersion + (tableFormat != null ? tableFormat.toString() : " [no data read]");
			return str;
		}
		/**
		 * @return The length of the table
		 */
		public int getLength() {
			return this.length;
		}

		/**
		 * @return The table format
		 */
		public TableFormat getTableFormat() {
			return this.tableFormat;
		}

	}

	public abstract class TableFormat {
		public abstract void read() throws IOException;
		public abstract int getGlyphIndex(int character);
	}

	public class TableFormat0 extends TableFormat {

		public int[] glyphIdArray = new int[256];

		public void read() throws IOException {
			for (int i = 0; i < glyphIdArray.length; i++)
				glyphIdArray[i] = ttf.readByte();
		}

		public String toString() {
			String str = "";
			for (int i = 0; i < glyphIdArray.length; i++) {
				if (i % 16 == 0)
					str += "\n    " + Integer.toHexString(i / 16) + "x: ";
				String number = glyphIdArray[i] + "";
				while (number.length() < 3)
					number = " " + number;
				str += number + " ";
			}
			return str;
		}

		public int getGlyphIndex(int character) {
			return glyphIdArray[character];
		}
	}

	public class TableFormat4 extends TableFormat {

		public int segCount;
		public int[] endCount, startCount, idRangeOffset;
		public short[] idDelta; // could be int (ushort) as well

		public void read() throws IOException {
			segCount = ttf.readUShort() / 2;
			// dump the next three ushorts to /dev/null as they guy
			// who invented them really must have drunk a lot
			ttf.readUShort();
			ttf.readUShort();
			ttf.readUShort();

			//endCount = readFFFFTerminatedUShortArray();
			endCount = ttf.readUShortArray(segCount);
			int reservedPad = ttf.readUShort();
			if (reservedPad != 0)
				System.err.println("reservedPad not 0, but " + reservedPad + ".");

			startCount = ttf.readUShortArray(endCount.length);
			// the deltas should be unsigned, but due to
			// modulo arithmetic it makes no difference
			idDelta = ttf.readShortArray(endCount.length);
			idRangeOffset = ttf.readUShortArray(endCount.length);
		}

		public String toString() {
			String str = "\n   " + endCount.length + " sections:";
			for (int i = 0; i < endCount.length; i++)
				str += "\n    " + startCount[i] + " to " + endCount[i] + " : " + idDelta[i] + " (" + idRangeOffset[i] + ")";
			return str;
		}

		public int getGlyphIndex(int character) {
			return 0;
		}
	}

	public String getTag() {
		return "cmap";
	}

	public void readTable() throws IOException {
		version = ttf.readUShort();
		encodingTable = new EncodingTable[ttf.readUShort()];
		for (int i = 0; i < encodingTable.length; i++) {
			encodingTable[i] = new EncodingTable();
			encodingTable[i].readHeader();
		}
		for (int i = 0; i < encodingTable.length; i++) {
			encodingTable[i].readBody();
		}
	}
	public class TableFormat6 extends TableFormat {
		public int firstCode = 0, entryCount = 0;
		public int[] glyphIdArray;

		public void read() throws IOException {
			// read first character code of subrange
			firstCode = ttf.readUShort();
			//read entryCount  Number of character codes in subrange.
			entryCount = ttf.readUShort();

			glyphIdArray = new int[entryCount];

			for (int i = 0; i < entryCount; i++)
				glyphIdArray[i] = ttf.readUShort();
		}

		public String toString() {
			String str = "";
			for (int i = 0; i < glyphIdArray.length; i++) {
				if (i % 16 == 0)
					str += "\n    " + Integer.toHexString(i / 16) + "x: ";
				String number = glyphIdArray[i] + "";
				while (number.length() < 3)
					number = " " + number;
				str += number + " ";
			}
			return str;
		}

		public int getGlyphIndex(int character) {
			if (character < this.firstCode || character > this.firstCode + this.entryCount)
				return glyphIdArray[0];
			else
				return glyphIdArray[character - this.firstCode];
		}
	}

	public String toString() {
		String str = super.toString() + " v" + version;
		for (int i = 0; i < encodingTable.length; i++)
			str += "\n  " + encodingTable[i];
		return str;
	}
}