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<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Pdf
* @subpackage Fonts
* @copyright Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: SegmentToDelta.php 18993 2009-11-15 17:09:16Z alexander $
*/
/** Zend_Pdf_Cmap */
require_once 'Zend/Pdf/Cmap.php';
/**
* Implements the "segment mapping to delta values" character map (type 4).
*
* This is the Microsoft standard mapping table type for OpenType fonts. It
* provides the ability to cover multiple contiguous ranges of the Unicode
* character set, with the exception of Unicode Surrogates (U+D800 - U+DFFF).
*
* @package Zend_Pdf
* @subpackage Fonts
* @copyright Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_Pdf_Cmap_SegmentToDelta extends Zend_Pdf_Cmap
{
/**** Instance Variables ****/
/**
* The number of segments in the table.
* @var integer
*/
protected $_segmentCount = 0;
/**
* The size of the binary search range for segments.
* @var integer
*/
protected $_searchRange = 0;
/**
* The number of binary search steps required to cover the entire search
* range.
* @var integer
*/
protected $_searchIterations = 0;
/**
* Array of ending character codes for each segment.
* @var array
*/
protected $_segmentTableEndCodes = array();
/**
* The ending character code for the segment at the end of the low search
* range.
* @var integer
*/
protected $_searchRangeEndCode = 0;
/**
* Array of starting character codes for each segment.
* @var array
*/
protected $_segmentTableStartCodes = array();
/**
* Array of character code to glyph delta values for each segment.
* @var array
*/
protected $_segmentTableIdDeltas = array();
/**
* Array of offsets into the glyph index array for each segment.
* @var array
*/
protected $_segmentTableIdRangeOffsets = array();
/**
* Glyph index array. Stores glyph numbers, used with range offset.
* @var array
*/
protected $_glyphIndexArray = array();
/**** Public Interface ****/
/* Concrete Class Implementation */
/**
* Returns an array of glyph numbers corresponding to the Unicode characters.
*
* If a particular character doesn't exist in this font, the special 'missing
* character glyph' will be substituted.
*
* See also {@link glyphNumberForCharacter()}.
*
* @param array $characterCodes Array of Unicode character codes (code points).
* @return array Array of glyph numbers.
*/
public function glyphNumbersForCharacters($characterCodes)
{
$glyphNumbers = array();
foreach ($characterCodes as $key => $characterCode) {
/* These tables only cover the 16-bit character range.
*/
if ($characterCode > 0xffff) {
$glyphNumbers[$key] = Zend_Pdf_Cmap::MISSING_CHARACTER_GLYPH;
continue;
}
/* Determine where to start the binary search. The segments are
* ordered from lowest-to-highest. We are looking for the first
* segment whose end code is greater than or equal to our character
* code.
*
* If the end code at the top of the search range is larger, then
* our target is probably below it.
*
* If it is smaller, our target is probably above it, so move the
* search range to the end of the segment list.
*/
if ($this->_searchRangeEndCode >= $characterCode) {
$searchIndex = $this->_searchRange;
} else {
$searchIndex = $this->_segmentCount;
}
/* Now do a binary search to find the first segment whose end code
* is greater or equal to our character code. No matter the number
* of segments (there may be hundreds in a large font), we will only
* need to perform $this->_searchIterations.
*/
for ($i = 1; $i <= $this->_searchIterations; $i++) {
if ($this->_segmentTableEndCodes[$searchIndex] >= $characterCode) {
$subtableIndex = $searchIndex;
$searchIndex -= $this->_searchRange >> $i;
} else {
$searchIndex += $this->_searchRange >> $i;
}
}
/* If the segment's start code is greater than our character code,
* that character is not represented in this font. Move on.
*/
if ($this->_segmentTableStartCodes[$subtableIndex] > $characterCode) {
$glyphNumbers[$key] = Zend_Pdf_Cmap::MISSING_CHARACTER_GLYPH;
continue;
}
if ($this->_segmentTableIdRangeOffsets[$subtableIndex] == 0) {
/* This segment uses a simple mapping from character code to
* glyph number.
*/
$glyphNumbers[$key] = ($characterCode + $this->_segmentTableIdDeltas[$subtableIndex]) % 65536;
} else {
/* This segment relies on the glyph index array to determine the
* glyph number. The calculation below determines the correct
* index into that array. It's a little odd because the range
* offset in the font file is designed to quickly provide an
* address of the index in the raw binary data instead of the
* index itself. Since we've parsed the data into arrays, we
* must process it a bit differently.
*/
$glyphIndex = ($characterCode - $this->_segmentTableStartCodes[$subtableIndex] +
$this->_segmentTableIdRangeOffsets[$subtableIndex] - $this->_segmentCount +
$subtableIndex - 1);
$glyphNumbers[$key] = $this->_glyphIndexArray[$glyphIndex];
}
}
return $glyphNumbers;
}
/**
* Returns the glyph number corresponding to the Unicode character.
*
* If a particular character doesn't exist in this font, the special 'missing
* character glyph' will be substituted.
*
* See also {@link glyphNumbersForCharacters()} which is optimized for bulk
* operations.
*
* @param integer $characterCode Unicode character code (code point).
* @return integer Glyph number.
*/
public function glyphNumberForCharacter($characterCode)
{
/* This code is pretty much a copy of glyphNumbersForCharacters().
* See that method for inline documentation.
*/
if ($characterCode > 0xffff) {
return Zend_Pdf_Cmap::MISSING_CHARACTER_GLYPH;
}
if ($this->_searchRangeEndCode >= $characterCode) {
$searchIndex = $this->_searchRange;
} else {
$searchIndex = $this->_segmentCount;
}
for ($i = 1; $i <= $this->_searchIterations; $i++) {
if ($this->_segmentTableEndCodes[$searchIndex] >= $characterCode) {
$subtableIndex = $searchIndex;
$searchIndex -= $this->_searchRange >> $i;
} else {
$searchIndex += $this->_searchRange >> $i;
}
}
if ($this->_segmentTableStartCodes[$subtableIndex] > $characterCode) {
return Zend_Pdf_Cmap::MISSING_CHARACTER_GLYPH;
}
if ($this->_segmentTableIdRangeOffsets[$subtableIndex] == 0) {
$glyphNumber = ($characterCode + $this->_segmentTableIdDeltas[$subtableIndex]) % 65536;
} else {
$glyphIndex = ($characterCode - $this->_segmentTableStartCodes[$subtableIndex] +
$this->_segmentTableIdRangeOffsets[$subtableIndex] - $this->_segmentCount +
$subtableIndex - 1);
$glyphNumber = $this->_glyphIndexArray[$glyphIndex];
}
return $glyphNumber;
}
/**
* Returns an array containing the Unicode characters that have entries in
* this character map.
*
* @return array Unicode character codes.
*/
public function getCoveredCharacters()
{
$characterCodes = array();
for ($i = 1; $i <= $this->_segmentCount; $i++) {
for ($code = $this->_segmentTableStartCodes[$i]; $code <= $this->_segmentTableEndCodes[$i]; $code++) {
$characterCodes[] = $code;
}
}
return $characterCodes;
}
/**
* Returns an array containing the glyphs numbers that have entries in this character map.
* Keys are Unicode character codes (integers)
*
* This functionality is partially covered by glyphNumbersForCharacters(getCoveredCharacters())
* call, but this method do it in more effective way (prepare complete list instead of searching
* glyph for each character code).
*
* @internal
* @return array Array representing <Unicode character code> => <glyph number> pairs.
*/
public function getCoveredCharactersGlyphs()
{
$glyphNumbers = array();
for ($segmentNum = 1; $segmentNum <= $this->_segmentCount; $segmentNum++) {
if ($this->_segmentTableIdRangeOffsets[$segmentNum] == 0) {
$delta = $this->_segmentTableIdDeltas[$segmentNum];
for ($code = $this->_segmentTableStartCodes[$segmentNum];
$code <= $this->_segmentTableEndCodes[$segmentNum];
$code++) {
$glyphNumbers[$code] = ($code + $delta) % 65536;
}
} else {
$code = $this->_segmentTableStartCodes[$segmentNum];
$glyphIndex = $this->_segmentTableIdRangeOffsets[$segmentNum] - ($this->_segmentCount - $segmentNum) - 1;
while ($code <= $this->_segmentTableEndCodes[$segmentNum]) {
$glyphNumbers[$code] = $this->_glyphIndexArray[$glyphIndex];
$code++;
$glyphIndex++;
}
}
}
return $glyphNumbers;
}
/* Object Lifecycle */
/**
* Object constructor
*
* Parses the raw binary table data. Throws an exception if the table is
* malformed.
*
* @param string $cmapData Raw binary cmap table data.
* @throws Zend_Pdf_Exception
*/
public function __construct($cmapData)
{
/* Sanity check: The table should be at least 23 bytes in size.
*/
$actualLength = strlen($cmapData);
if ($actualLength < 23) {
require_once 'Zend/Pdf/Exception.php';
throw new Zend_Pdf_Exception('Insufficient table data',
Zend_Pdf_Exception::CMAP_TABLE_DATA_TOO_SMALL);
}
/* Sanity check: Make sure this is right data for this table type.
*/
$type = $this->_extractUInt2($cmapData, 0);
if ($type != Zend_Pdf_Cmap::TYPE_SEGMENT_TO_DELTA) {
require_once 'Zend/Pdf/Exception.php';
throw new Zend_Pdf_Exception('Wrong cmap table type',
Zend_Pdf_Exception::CMAP_WRONG_TABLE_TYPE);
}
$length = $this->_extractUInt2($cmapData, 2);
if ($length != $actualLength) {
require_once 'Zend/Pdf/Exception.php';
throw new Zend_Pdf_Exception("Table length ($length) does not match actual length ($actualLength)",
Zend_Pdf_Exception::CMAP_WRONG_TABLE_LENGTH);
}
/* Mapping tables should be language-independent. The font may not work
* as expected if they are not. Unfortunately, many font files in the
* wild incorrectly record a language ID in this field, so we can't
* call this a failure.
*/
$language = $this->_extractUInt2($cmapData, 4);
if ($language != 0) {
// Record a warning here somehow?
}
/* These two values are stored premultiplied by two which is convienent
* when using the binary data directly, but we're parsing it out to
* native PHP data types, so divide by two.
*/
$this->_segmentCount = $this->_extractUInt2($cmapData, 6) >> 1;
$this->_searchRange = $this->_extractUInt2($cmapData, 8) >> 1;
$this->_searchIterations = $this->_extractUInt2($cmapData, 10) + 1;
$offset = 14;
for ($i = 1; $i <= $this->_segmentCount; $i++, $offset += 2) {
$this->_segmentTableEndCodes[$i] = $this->_extractUInt2($cmapData, $offset);
}
$this->_searchRangeEndCode = $this->_segmentTableEndCodes[$this->_searchRange];
$offset += 2; // reserved bytes
for ($i = 1; $i <= $this->_segmentCount; $i++, $offset += 2) {
$this->_segmentTableStartCodes[$i] = $this->_extractUInt2($cmapData, $offset);
}
for ($i = 1; $i <= $this->_segmentCount; $i++, $offset += 2) {
$this->_segmentTableIdDeltas[$i] = $this->_extractInt2($cmapData, $offset); // signed
}
/* The range offset helps determine the index into the glyph index array.
* Like the segment count and search range above, it's stored as a byte
* multiple in the font, so divide by two as we extract the values.
*/
for ($i = 1; $i <= $this->_segmentCount; $i++, $offset += 2) {
$this->_segmentTableIdRangeOffsets[$i] = $this->_extractUInt2($cmapData, $offset) >> 1;
}
/* The size of the glyph index array varies by font and depends on the
* extent of the usage of range offsets versus deltas. Some fonts may
* not have any entries in this array.
*/
for (; $offset < $length; $offset += 2) {
$this->_glyphIndexArray[] = $this->_extractUInt2($cmapData, $offset);
}
/* Sanity check: After reading all of the data, we should be at the end
* of the table.
*/
if ($offset != $length) {
require_once 'Zend/Pdf/Exception.php';
throw new Zend_Pdf_Exception("Ending offset ($offset) does not match length ($length)",
Zend_Pdf_Exception::CMAP_FINAL_OFFSET_NOT_LENGTH);
}
}
}
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