1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.fontbox.ttf;
18
19 import java.io.IOException;
20
21 /**
22 * An encoding entry for a cmap.
23 *
24 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
25 * @version $Revision: 1.2 $
26 */
27 public class CMAPEncodingEntry
28 {
29
30 private int platformId;
31 private int platformEncodingId;
32 private long subTableOffset;
33 private int[] glyphIdToCharacterCode;
34 /**
35 * This will read the required data from the stream.
36 *
37 * @param ttf The font that is being read.
38 * @param data The stream to read the data from.
39 * @throws IOException If there is an error reading the data.
40 */
41 public void initData( TrueTypeFont ttf, TTFDataStream data ) throws IOException
42 {
43 platformId = data.readUnsignedShort();
44 platformEncodingId = data.readUnsignedShort();
45 subTableOffset = data.readUnsignedInt();
46 }
47
48 /**
49 * This will read the required data from the stream.
50 *
51 * @param ttf The font that is being read.
52 * @param data The stream to read the data from.
53 * @throws IOException If there is an error reading the data.
54 */
55 public void initSubtable( TrueTypeFont ttf, TTFDataStream data ) throws IOException
56 {
57 data.seek( ttf.getCMAP().getOffset() + subTableOffset );
58 int subtableFormat = data.readUnsignedShort();
59 int length = data.readUnsignedShort();
60 int version = data.readUnsignedShort();
61 int numGlyphs = ttf.getMaximumProfile().getNumGlyphs();
62 if( subtableFormat == 0 )
63 {
64 byte[] glyphMapping = data.read( 256 );
65 glyphIdToCharacterCode = new int[256];
66 for( int i=0;i<glyphMapping.length; i++ )
67 {
68 glyphIdToCharacterCode[i]=(glyphMapping[i]+256)%256;
69 }
70 }
71 else if( subtableFormat == 2 )
72 {
73 int[] subHeaderKeys = new int[256];
74 for( int i=0; i<256; i++)
75 {
76 subHeaderKeys[i] = data.readUnsignedShort();
77 }
78 int firstCode = data.readUnsignedShort();
79 int entryCount = data.readUnsignedShort();
80 short idDelta = data.readSignedShort();
81 int idRangeOffset = data.readUnsignedShort();
82 //BJL
83 //HMM the TTF spec is not very clear about what is suppose to
84 //happen here. If you know please submit a patch or point
85 //me to some better documentation.
86 throw new IOException( "Not yet implemented:" + subtableFormat );
87 }
88 else if( subtableFormat == 4 )
89 {
90 int segCountX2 = data.readUnsignedShort();
91 int segCount = segCountX2/2;
92 int searchRange = data.readUnsignedShort();
93 int entrySelector = data.readUnsignedShort();
94 int rangeShift = data.readUnsignedShort();
95 int[] endCount = data.readUnsignedShortArray( segCount );
96 int reservedPad = data.readUnsignedShort();
97 int[] startCount = data.readUnsignedShortArray( segCount );
98 int[] idDelta = data.readUnsignedShortArray( segCount );
99 int[] idRangeOffset = data.readUnsignedShortArray( segCount );
100
101 //this is the final result
102 //key=glyphId, value is character codes
103 glyphIdToCharacterCode = new int[numGlyphs];
104
105 long currentPosition = data.getCurrentPosition();
106
107 for( int i=0; i<segCount; i++ )
108 {
109 int start = startCount[i];
110 int end = endCount[i];
111 int delta = idDelta[i];
112 int rangeOffset = idRangeOffset[i];
113 if( start != 65535 && end != 65535 )
114 {
115 for( int j=start; j<=end; j++ )
116 {
117 if( rangeOffset == 0 )
118 {
119 glyphIdToCharacterCode[ ((j+delta)%65536) ]=j;
120 }
121 else
122 {
123 long glyphOffset = currentPosition +
124 ((rangeOffset/2) + //idRangeOffset[i]/2
125 (j-start) + //(c - startCount[i])
126 (i-segCount))*2; //&idRangeOffset[i]);
127 data.seek( glyphOffset );
128 int glyphIndex = data.readUnsignedShort();
129 if( glyphIndex != 0 )
130 {
131 glyphIndex += delta;
132 glyphIndex = glyphIndex % 65536;
133 if( glyphIdToCharacterCode[glyphIndex] == 0 )
134 {
135 glyphIdToCharacterCode[glyphIndex] = j;
136 }
137 }
138
139 }
140 }
141 }
142 }
143 }
144 else if( subtableFormat == 6 )
145 {
146 int firstCode = data.readUnsignedShort();
147 int entryCount = data.readUnsignedShort();
148 glyphIdToCharacterCode = new int[numGlyphs];
149 int[] glyphIdArray = data.readUnsignedShortArray( entryCount );
150 for( int i=0; i<entryCount; i++)
151 {
152 glyphIdToCharacterCode[glyphIdArray[i]] = firstCode+i;
153 }
154 }
155 else
156 {
157 throw new IOException( "Unknown cmap format:" + subtableFormat );
158 }
159 }
160
161
162 /**
163 * @return Returns the glyphIdToCharacterCode.
164 */
165 public int[] getGlyphIdToCharacterCode()
166 {
167 return glyphIdToCharacterCode;
168 }
169 /**
170 * @param glyphIdToCharacterCodeValue The glyphIdToCharacterCode to set.
171 */
172 public void setGlyphIdToCharacterCode(int[] glyphIdToCharacterCodeValue)
173 {
174 this.glyphIdToCharacterCode = glyphIdToCharacterCodeValue;
175 }
176
177 /**
178 * @return Returns the platformEncodingId.
179 */
180 public int getPlatformEncodingId()
181 {
182 return platformEncodingId;
183 }
184 /**
185 * @param platformEncodingIdValue The platformEncodingId to set.
186 */
187 public void setPlatformEncodingId(int platformEncodingIdValue)
188 {
189 this.platformEncodingId = platformEncodingIdValue;
190 }
191 /**
192 * @return Returns the platformId.
193 */
194 public int getPlatformId()
195 {
196 return platformId;
197 }
198 /**
199 * @param platformIdValue The platformId to set.
200 */
201 public void setPlatformId(int platformIdValue)
202 {
203 this.platformId = platformIdValue;
204 }
205 }