org.apache.fop.fonts.CIDSubset Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: CIDSubset.java 828516 2009-10-22 09:16:37Z jeremias $ */
package org.apache.fop.fonts;
import java.util.BitSet;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import org.apache.fop.util.CharUtilities;
//Naming:
//glyph index: original index of the glyph in the non-subset font (!= unicode index)
//character selector: index into a set of glyphs. For subset CID fonts, this starts at 0. For
// non-subset fonts, this is the same as the glyph index.
//Unicode index: The Unicode codepoint of a character.
//Glyph name: the Adobe glyph name (as found in Glyphs.java)
/**
* Keeps track of the glyphs used in a document. This information is later used to build
* a subset of a font.
*/
public class CIDSubset {
/**
* usedGlyphs contains orginal, new glyph index (glyph index -> char selector)
*/
private Map/**/ usedGlyphs = new java.util.HashMap();
/**
* usedGlyphsIndex contains new glyph, original index (char selector -> glyph index)
*/
private Map/**/ usedGlyphsIndex = new java.util.HashMap();
private int usedGlyphsCount = 0;
/**
* usedCharsIndex contains new glyph, original char (char selector -> Unicode)
*/
private Map/**/ usedCharsIndex = new java.util.HashMap();
public CIDSubset() {
}
/**
* Adds the initial 3 glyphs which are the same for all CID subsets.
*/
public void setupFirstThreeGlyphs() {
// Make sure that the 3 first glyphs are included
usedGlyphs.put(new Integer(0), new Integer(0));
usedGlyphsIndex.put(new Integer(0), new Integer(0));
usedGlyphsCount++;
usedGlyphs.put(new Integer(1), new Integer(1));
usedGlyphsIndex.put(new Integer(1), new Integer(1));
usedGlyphsCount++;
usedGlyphs.put(new Integer(2), new Integer(2));
usedGlyphsIndex.put(new Integer(2), new Integer(2));
usedGlyphsCount++;
}
/**
* Returns the original index of the glyph inside the (non-subset) font's glyph list. This
* index can be used to access the character width information, for example.
* @param subsetIndex the subset index (character selector) to access the glyph
* @return the original index (or -1 if no glyph index is available for the subset index)
*/
public int getGlyphIndexForSubsetIndex(int subsetIndex) {
Integer glyphIndex = (Integer)usedGlyphsIndex.get(new Integer(subsetIndex));
if (glyphIndex != null) {
return glyphIndex.intValue();
} else {
return -1;
}
}
/**
* Returns the Unicode value for a subset index (character selector). If there's no such
* Unicode value, the "NOT A CHARACTER" (0xFFFF) is returned.
* @param subsetIndex the subset index (character selector)
* @return the Unicode value or "NOT A CHARACTER" (0xFFFF)
*/
public char getUnicodeForSubsetIndex(int subsetIndex) {
Character mapValue = (Character)usedCharsIndex.get(new Integer(subsetIndex));
if (mapValue != null) {
return mapValue.charValue();
} else {
return CharUtilities.NOT_A_CHARACTER;
}
}
/**
* Maps a character to a character selector for a font subset. If the character isn't in the
* subset, yet, it is added and a new character selector returned. Otherwise, the already
* allocated character selector is returned from the existing map/subset.
* @param glyphIndex the glyph index of the character
* @param unicode the Unicode index of the character
* @return the subset index
*/
public int mapSubsetChar(int glyphIndex, char unicode) {
// Reencode to a new subset font or get the reencoded value
// IOW, accumulate the accessed characters and build a character map for them
Integer subsetCharSelector = (Integer)usedGlyphs.get(new Integer(glyphIndex));
if (subsetCharSelector == null) {
int selector = usedGlyphsCount;
usedGlyphs.put(new Integer(glyphIndex),
new Integer(selector));
usedGlyphsIndex.put(new Integer(selector),
new Integer(glyphIndex));
usedCharsIndex.put(new Integer(selector),
new Character(unicode));
usedGlyphsCount++;
return selector;
} else {
return subsetCharSelector.intValue();
}
}
/**
* Returns an unmodifiable Map of the font subset. It maps from glyph index to
* character selector (i.e. the subset index in this case).
* @return Map Map<Integer, Integer> of the font subset
*/
public Map/**/ getSubsetGlyphs() {
return Collections.unmodifiableMap(this.usedGlyphs);
}
/**
* Returns a char array containing all Unicode characters that are in the subset.
* @return a char array with all used Unicode characters
*/
public char[] getSubsetChars() {
char[] charArray = new char[usedGlyphsCount];
for (int i = 0; i < usedGlyphsCount; i++) {
charArray[i] = getUnicodeForSubsetIndex(i);
}
return charArray;
}
/**
* Returns the number of glyphs in the subset.
* @return the number of glyphs in the subset
*/
public int getSubsetSize() {
return this.usedGlyphsCount;
}
/**
* Returns a BitSet with bits set for each available glyph index in the subset.
* @return a BitSet indicating available glyph indices
*/
public BitSet getGlyphIndexBitSet() {
BitSet bitset = new BitSet();
Iterator iter = usedGlyphsIndex.keySet().iterator();
while (iter.hasNext()) {
Integer cid = (Integer)iter.next();
bitset.set(cid.intValue());
}
return bitset;
}
}