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// Bidi.cpp - version 26
// Reference implementation for Unicode Bidirectional Algorithm
// Set WINDOWS_UI to 0 to get commandline UI
// Set WINDOWS_UI to 1 for generic win 32 dialog
// Set WINDOWS_UI to 2 for private build
#ifndef WINDOWS_UI
#define WINDOWS_UI 2
#endif
// Bidi include file
#include "bidi.h"
// Set to 0 for default
// Set to 1 to run in debug mode
#ifndef DEBUGGING
#define DEBUGGING 0
#else
#define DEMO 1
#endif
// Debug mode enables Demo mode
// Debug mode enables Table checks
// Set to 1 if demo operation is
// desired outside debug mode
#ifndef DEMO
#define DEMO 0
#endif
// Demo mode restricts levels to 15
/*------------------------------------------------------------------------
File: Bidi.Cpp
Description
-----------
Sample Implementation of the Unicode Bidirectional Algorithm as it
was revised by Revision 5 of the Uniode Technical Report # 9
(1999-8-17)
Verified for changes to the algorithm up through Unicode 5.2.0 (2009).
This implementation is organized into several passes, each implemen-
ting one or more of the rules of the Unicode Bidi Algorithm. The
resolution of Weak Types and of Neutrals each use a state table
approach.
Both a printf based interface and a Windows DlgProc are provided for
interactive testing.
A stress harness comparing this implementation (v24) to a Java based
implementation was used by Doug Felt to verify that the two
implementations produce identical results for all strings up to six
bidi classes and stochastic strings up to length 20.
Version 26 was verified by the author against the Unicode 5.2.0
file BidiTest.txt, which provides an exhaustive text of strings of
length 4 or less, but covers some important cases where the language
in UAX#9 had been clarified.
To see this code running in an actual Windows program,
download the free Unibook uitlity from http://unicode.org/unibook
The bidi demo is executed from the tools menu. It is build from
this source file.
Build Notes
-----------
To compile the sample implementation please set the #define
directives above so the correct headers get included. Not all the
files are needed for all purposes. For the commandline version
only bidi.h and bidi.cpp are needed.
The Win32 version is provided as a dialog procedure. To use as a
standalone program compile with the the lbmain.cpp file. If all you
need is the ability to run the code "as is", you can instead download
the unibook utility from http://uincode.org/unibook/ which contains
the bidi demo compiled from this source file.
This code uses an extension to C++ that gives variables declared in
a for() statement function the same scope as the for() statement.
If your compiler does not support this extension, you may need to
move the declaration, e.g. int ich = 0; in front of the for statement.
Implementation Note
-------------------
NOTE: The Unicode Bidirectional Algorithm removes all explicit
formatting codes in rule X9, but states that this can be
simulated by conformant implementations. This implementation
attempts to demonstrate such a simulation
To demonstrate this, the current implementation does the
following:
in resolveExplicit()
- change LRE, LRO, RLE, RLO, PDF to BN
- assign nested levels to BN
in resolveWeak and resolveNeutrals
- assign L and R to BN's where they exist in place of
sor and eor by changing the last BN in front of a
level change to a strong type
- skip over BN's for the purpose of determining actions
- include BN in the count of deferred runs
which will resolve some of them to EN, AN and N
in resolveWhiteSpace
- set the level of any surviving BN to the base level,
or the level of the preceding character
- include LRE,LRO, RLE, RLO, PDF and BN in the count
whitespace to be reset
This will result in the same order for non-BN characters as
if the BN characters had been removed.
The clean() function can be used to remove boundary marks for
verification purposes.
Notation
--------
Pointer variables generally start with the letter p
Counter variables generally start with the letter c
Index variables generally start with the letter i
Boolean variables generally start with the letter f
The enumerated bidirectional types have the same name as in the
description for the Unicode Bidirectional Algorithm
Using this code outside a demo context
--------------------------------------
The way the functions are broken down in this demo code is based
on the needs of the demo to show the evolution in internal state
as the algorithm proceeds. This obscures how the algorithm would
be used in practice. These are the steps:
1. Allocate a pair of arrays large enough to hold bidi class
and calculated levels (one for each input character)
2. Provide your own function to assign directional types (bidi
classes) corresponding to each character in the input,
conflating ON, WS, S to N. Unlike the classify function in this
demo, the input would be actual Unicode characters.
3. Process the first paragraph by calling BidiParagraph. That
function changes B into BN and returns a length including the
paragraph separator. (The iteration over multiple paragraphs
is left as excercise for the reader).
4. Assign directional types again, but now assign specific types
to whitespace characters.
5. Instead of reordering the input in place it is often desirable
to calculate an array of offsets indicating the reordering.
To that end, allocate such an array here and use it instead
of the input array in the next step.
6. Resolve and reorder the lines by calling BidiLines. That
function 'breaks' lines on LS characters. Provide an optional
array of flags indicating the location of other line breaks as
needed.
Update History
--------------
Version 24 is the initial published and verified version of this
reference implementation. Version 25 and its updates fix various
minor issues with the scaffolding used for demonstrating the
algorithm using pseudo-alphabets from the command line or dialog
box. No changes to the implementation of the actual bidi algrithm
are made in any of the minor updates to version 25. Version 26
also makes no change to the actual algorithm but was verified
against the official BidiTest.txt file for Unicode 5.2.0.
- updated pseudo-alphabet
- Last Revised 12-10-99 (25)
- enable demo mode for release builds - no other changes
- Last Revised 12-10-00 (25a)
- fix regression in pseudo alphabet use for Windows UI
- Last Revised 02-01-01 (25b)
- fixed a few comments, renamed a variable
- Last Revised 03-04-01 (25c)
- make base level settable, enable mirror by default,
fix dialog size
- Last Revised 06-02-01 (25e)
- fixed some comments
- Last Revised 09-29-01 (25f)
- fixed classification for LS,RLM,LRM in pseudo alphabet,
focus issues in UI, regression fix to commandline from 25(e)
fix DEMO switch
- Last Revised 11-07-01 (25g)
- fixed classification for plus/minus in pseudo alphabet
to track changes made in Unicode 4.0.1
- Last Revised 12-03-04 (25h)
- now compiles as dialog-only program for WINDOWS_UI==1
using new bidimain.cpp
- Last Revised 12-02-07 (25i)
- cleaned up whitespace and indenting in the source,
fixed two comments (table headers)
- Last Revised 15-03-07 (25j)
- named enumerations
- Last Revised 30-05-07 (25k)
- added usage notes, minor edits to comments, indentation, etc
throughout. Added the bidiParagraph function. Checked against
changes in the Unicode Bidi Algorithm for Unicode 5.2.0. No
changes needed to this implementation to match the values in
the BidiTest.txt file in the Unicode Character Database.
Minor fixes to dialog/windows proc, updated preprocessor directives.
- Last Revised 03-08-09 (26)
Credits:
-------
Written by: Asmus Freytag
Command line interface by: Rick McGowan
Verification (v24): Doug Felt
Disclaimer and legal rights:
---------------------------
Copyright (C) 1999-2009, ASMUS, Inc. All Rights Reserved.
Distributed under the Terms of Use in http://www.unicode.org/copyright.html.
THIS SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE
BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES,
OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THE SOFTWARE.
The file bid.rc is included in the software covered by the above.
------------------------------------------------------------------------*/
// === HELPER FUNCTIONS AND DECLARATIONS =================================
#define odd(x) ((x) & 1)
/*------------------------------------------------------------------------
Bidirectional Character Types
as defined by the Unicode Bidirectional Algorithm Table 3-7.
Note:
The list of bidirectional character types here is not grouped the
same way as the table 3-7, since the numberic values for the types
are chosen to keep the state and action tables compact.
------------------------------------------------------------------------*/
enum bidi_class
{
// input types
// ON MUST be zero, code relies on ON = N = 0
ON = 0, // Other Neutral
L, // Left Letter
R, // Right Letter
AN, // Arabic Number
EN, // European Number
AL, // Arabic Letter (Right-to-left)
NSM, // Non-spacing Mark
CS, // Common Separator
ES, // European Separator
ET, // European Terminator (post/prefix e.g. $ and %)
// resolved types
BN, // Boundary neutral (type of RLE etc after explicit levels)
// input types,
S, // Segment Separator (TAB) // used only in L1
WS, // White space // used only in L1
B, // Paragraph Separator (aka as PS)
// types for explicit controls
RLO, // these are used only in X1-X9
RLE,
LRO,
LRE,
PDF,
// resolved types, also resolved directions
N = ON, // alias, where ON, WS and S are treated the same
};
/*----------------------------------------------------------------------
The following array maps character codes to types for the purpose of
this sample implementation. The legend string gives a human readable
explanation of the pseudo alphabet.
For simplicity, characters entered by buttons are given a 1:1 mapping
between their type and pseudo character value. Pseudo characters that
can be typed from the keyboard are explained in the legend string.
Use the Unicode Character Database for the real values in real use.
---------------------------------------------------------------------*/
#if WINDOWS_UI
const TCHAR legend[] =
TEXT("This sample uses the following pseudo-alphabet as input\r\n")
TEXT("Excplicit: LRE: [ RLE: ] LRO: { RLO: } PDF: 0x12,^ \r\n")
TEXT("Strong: AL: A-F R: 0x17,G-Z L: 0x16,a-z LRM: <btn> RLM: <btn> \r\n")
TEXT("Numeric: EN: 0-5 AN: 6-9 CS: [comma],.,: ES: /,+,- ET: #,$,% \r\n")
TEXT("Neutral: WS: 0xc,0x15,[space] ON: !,\",&,',(,),*,;,<,=,>,?,@,\\,0x7f \r\n")
TEXT("Special: NSM: ` B: | S: _ BN: ~ ");
#endif
const int chLRM = 4;
const int chRLM = 5;
const int chLS = 0x15;
const int chRLO = '}';
const int chLRO = '{';
const int chRLE = ']';
const int chLRE = '[';
const int chPDF = '^';
const int chBN = '~';
int TypesFromChar[] =
{
//0 1 2 3 4 5 6 7 8 9 a b c d e f
BN, BN, BN, BN, L, R, BN, BN, BN, S, B, S, WS, B, BN, BN, /*00-0f*/
LRO,LRE,PDF,RLO,RLE, WS, L, R, BN, BN, BN, BN, B, B, B, S, /*10-1f*/
WS, ON, ON, ET, ET, ET, ON, ON, ON, ON, ON, ES, CS, ES, CS, ES, /*20-2f*/
EN, EN, EN, EN, EN, EN, AN, AN, AN, AN, CS, ON, ON, ON, ON, ON, /*30-3f*/
ON, AL, AL, AL, AL, AL, AL, R, R, R, R, R, R, R, R, R, /*40-4f*/
R, R, R, R, R, R, R, R, R, R, R,LRE, ON,RLE,PDF, S, /*50-5f*/
NSM, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, /*60-6f*/
L, L, L, L, L, L, L, L, L, L, L,LRO, B,RLO, BN, ON, /*70-7f*/
};
/***************************************
Reverse, human readable reference:
LRM: 0x4
RLM: 0x5
L: 0x16,a-z
LRE: 0x11,[
LRO: 0x10,{
R: 0x17,G-Z
AL: A-F
RLE: 0x14,]
RLO: 0x13,}
PDF: 0x12,^
EN: 0-5
ES: /,+,[hyphen]
ET: #,$,%
AN: 6-9
CS: [comma],.,:
NSM: `
BN: 0x0-0x8,0xe,0xf,0x18-0x1b,~
B: 0xa,0xd,0x1c-0x1e,|
S: 0x9,0xb,0x1f,_
WS: 0xc,0x15,[space]
ON: !,",&,',(,),*,;,<,=,>,?,@,\,0x7f
****************************************/
// WS, LS and S are not explicitly needed except for L1. Therefore this
// table conflates ON, S, WS, and LS to N, all others unchanged
int NTypes[] = {
N, // ON,
L, // L,
R, // R,
AN, // AN,
EN, // EN,
AL, // AL
NSM, // NSM
CS, // CS
ES, // ES
ET, // ET
BN, // BN
N, // S
N, // WS
B, // B
RLO, // RLO
RLE, // RLE
LRO, // LRO
LRE, // LRE
PDF, // PDF
ON, // LS
};
int ClassFromChN(TCHAR ch)
{
ASSERT(ch < 0x7f && ch >= 0);
return NTypes[TypesFromChar[ch & 0x7f]];
}
int ClassFromChWS(TCHAR ch)
{
ASSERT(ch < 0x7f && ch >= 0);
return TypesFromChar[ch & 0x7f];
}
// === DISPLAY SUPPORT =================================================
#if WINDOWS_UI < 1 || !defined(UNICODE)
enum display_symbol // Display character codes
{
RIGHT = '<', // rtl arrow
LEFT = '>', // ltr arrow
PUSH = '+', // dn arrow
POP = '-', // up arrow
LSEP = '=', // double dagger
NEUTRAL = ' ', // rtl/ltr dbl headed arrow
ALPHA = 'a',
};
#else
enum display_symbol // Display character codes
{
RIGHT = 0x2190, // rtl arrow
LEFT = 0x2192, // rtl arrow
PUSH = 0x2193, // dn arrow
POP = 0x2191, // up arrow
LSEP = 0x2021, // double dagger
NEUTRAL = 0x2194, // rtl/ltr dbl headed arrow
ALPHA = 0x03B1, // greek alpha
};
#endif
// display support:
TCHAR CharFromTypes[] =
{
NEUTRAL, // ON,
LEFT, // L,
RIGHT, // R,
'9', // AN,
'1', // EN,
ALPHA, // AL
'@', // NSM
'.', // CS
',', // ES
'$', // ET
':', // BN
'X', // S
'_', // WS
'B', // B
PUSH, // RLO
PUSH, // RLE
PUSH, // LRO
PUSH, // LRE
POP, // PDF
LSEP, // LS
};
// This works only for testing
// a full implementation would need 61 levels....
TCHAR CharFromLevel[] =
{
'0', '1', '2', '3', '4',
'5', '6', '7', '8', '9',
'A', 'B', 'C', 'D', 'E',
'F', 'X', 'Y', 'Z' // overhang levels
};
// === HELPER FUNCTIONS ================================================
// reverse cch characters
void reverse(LPTSTR psz, int cch)
{
TCHAR chTemp;
for (int ich = 0; ich < --cch; ich++)
{
chTemp = psz[ich];
psz[ich] = psz[cch];
psz[cch] = chTemp;
}
}
// Set a run of cval values at locations all prior to, but not including
// iStart, to the new value nval.
void SetDeferredRun(int *pval, int cval, int iStart, int nval)
{
for (int i = iStart - 1; i >= iStart - cval; i--)
{
pval[i] = nval;
}
}
// === ASSIGNING BIDI CLASSES ============================================
/*------------------------------------------------------------------------
Function: classify
Determines the character classes for all following
passes of the algorithm
Input: Text string
Character count
Whether to report types as WS, ON, S or as N (false)
Output: Array of directional classes
------------------------------------------------------------------------*/
int classify(const LPTSTR pszText, int * pcls, int cch, bool fWS = false)
{
if (fWS)
{
for (int ich = 0; ich < cch; ich++)
{
pcls[ich] = ClassFromChWS(pszText[ich]);
}
return ich;
}
else
{
for (int ich = 0; ich < cch; ich++)
{
pcls[ich] = ClassFromChN(pszText[ich]);
}
return ich;
}
}
// === THE PARAGRAPH LEVEL ===============================================
/*------------------------------------------------------------------------
Function: resolveParagraphs
Resolves the input strings into blocks over which the algorithm
is then applied.
Implements Rule P1 of the Unicode Bidi Algorithm
Input: Text string
Character count
Output: revised character count
Note: This is a very simplistic function. In effect it restricts
the action of the algorithm to the first paragraph in the input
where a paragraph ends at the end of the first block separator
or at the end of the input text.
------------------------------------------------------------------------*/
int resolveParagraphs(int * types, int cch)
{
// skip characters not of type B
for(int ich = 0; ich < cch && types[ich] != B; ich++)
;
// stop after first B, make it a BN for use in the next steps
if (ich < cch && types[ich] == B)
types[ich++] = BN;
return ich;
}
/*------------------------------------------------------------------------
Function: baseLevel
Determines the base level
Implements rule P2 of the Unicode Bidi Algorithm.
Input: Array of directional classes
Character count
Note: Ignores explicit embeddings
------------------------------------------------------------------------*/
int baseLevel(const int * pcls, int cch)
{
for (int ich = 0; ich < cch; ich++)
{
switch (pcls[ich])
{
// strong left
case L:
return 0;
break;
// strong right
case R:
case AL:
return 1;
break;
}
}
return 0;
}
//====== RESOLVE EXPLICIT ================================================
int GreaterEven(int i)
{
return odd(i) ? i + 1 : i + 2;
}
int GreaterOdd(int i)
{
return odd(i) ? i + 2 : i + 1;
}
int EmbeddingDirection(int level)
{
return odd(level) ? R : L;
}
/*------------------------------------------------------------------------
Function: resolveExplicit
Recursively resolves explicit embedding levels and overrides.
Implements rules X1-X9, of the Unicode Bidirectional Algorithm.
Input: Base embedding level and direction
Character count
Output: Array of embedding levels
Caller must allocate (one level per input character)
In/Out: Array of direction classes
Note: The function uses two simple counters to keep track of
matching explicit codes and PDF. Use the default argument for
the outermost call. The nesting counter counts the recursion
depth and not the embedding level.
------------------------------------------------------------------------*/
#if DEMO
const int MAX_LEVEL = 15; // leave at the smaller level so we can test hitting
// the limit more easily in interactive mode
#else
const int MAX_LEVEL = 61; // the real value
#endif
int resolveExplicit(int level, int dir, int * pcls, int * plevel, int cch,
int nNest = 0)
{
// always called with a valid nesting level
// nesting levels are != embedding levels
int nLastValid = nNest;
// check input values
ASSERT(nNest >= 0 && level >= 0 && level <= MAX_LEVEL);
// process the text
for (int ich = 0; ich < cch; ich++)
{
int cls = pcls[ich];
switch (cls)
{
case LRO:
case LRE:
nNest++;
if (GreaterEven(level) <= MAX_LEVEL)
{
plevel[ich] = GreaterEven(level);
pcls[ich] = BN;
ich += resolveExplicit(plevel[ich], (cls == LRE ? N : L),
&pcls[ich+1], &plevel[ich+1],
cch - (ich+1), nNest);
nNest--;
continue;
}
cls = pcls[ich] = BN;
break;
case RLO:
case RLE:
nNest++;
if (GreaterOdd(level) <= MAX_LEVEL)
{
plevel[ich] = GreaterOdd(level);
pcls[ich] = BN;
ich += resolveExplicit(plevel[ich], (cls == RLE ? N : R),
&pcls[ich+1], &plevel[ich+1],
cch - (ich+1), nNest);
nNest--;
continue;
}
cls = pcls[ich] = BN;
break;
case PDF:
cls = pcls[ich] = BN;
if (nNest)
{
if (nLastValid < nNest)
{
nNest--;
}
else
{
cch = ich; // break the loop, but complete body
}
}
break;
}
// Apply the override
if (dir != N)
{
cls = dir;
}
plevel[ich] = level;
if (pcls[ich] != BN)
pcls[ich] = cls;
}
return ich;
}
// === RESOLVE WEAK TYPES ================================================
enum bidi_state // possible states
{
xa, // arabic letter
xr, // right leter
xl, // left letter
ao, // arabic lett. foll by ON
ro, // right lett. foll by ON
lo, // left lett. foll by ON
rt, // ET following R
lt, // ET following L
cn, // EN, AN following AL
ra, // arabic number foll R
re, // european number foll R
la, // arabic number foll L
le, // european number foll L
ac, // CS following cn
rc, // CS following ra
rs, // CS,ES following re
lc, // CS following la
ls, // CS,ES following le
ret, // ET following re
let, // ET following le
} ;
int stateWeak[][10] =
{
// N, L, R, AN, EN, AL,NSM, CS, ES, ET,
/*xa*/ ao, xl, xr, cn, cn, xa, xa, ao, ao, ao, /* arabic letter */
/*xr*/ ro, xl, xr, ra, re, xa, xr, ro, ro, rt, /* right letter */
/*xl*/ lo, xl, xr, la, le, xa, xl, lo, lo, lt, /* left letter */
/*ao*/ ao, xl, xr, cn, cn, xa, ao, ao, ao, ao, /* arabic lett. foll by ON*/
/*ro*/ ro, xl, xr, ra, re, xa, ro, ro, ro, rt, /* right lett. foll by ON */
/*lo*/ lo, xl, xr, la, le, xa, lo, lo, lo, lt, /* left lett. foll by ON */
/*rt*/ ro, xl, xr, ra, re, xa, rt, ro, ro, rt, /* ET following R */
/*lt*/ lo, xl, xr, la, le, xa, lt, lo, lo, lt, /* ET following L */
/*cn*/ ao, xl, xr, cn, cn, xa, cn, ac, ao, ao, /* EN, AN following AL */
/*ra*/ ro, xl, xr, ra, re, xa, ra, rc, ro, rt, /* arabic number foll R */
/*re*/ ro, xl, xr, ra, re, xa, re, rs, rs,ret, /* european number foll R */
/*la*/ lo, xl, xr, la, le, xa, la, lc, lo, lt, /* arabic number foll L */
/*le*/ lo, xl, xr, la, le, xa, le, ls, ls,let, /* european number foll L */
/*ac*/ ao, xl, xr, cn, cn, xa, ao, ao, ao, ao, /* CS following cn */
/*rc*/ ro, xl, xr, ra, re, xa, ro, ro, ro, rt, /* CS following ra */
/*rs*/ ro, xl, xr, ra, re, xa, ro, ro, ro, rt, /* CS,ES following re */
/*lc*/ lo, xl, xr, la, le, xa, lo, lo, lo, lt, /* CS following la */
/*ls*/ lo, xl, xr, la, le, xa, lo, lo, lo, lt, /* CS,ES following le */
/*ret*/ ro, xl, xr, ra, re, xa,ret, ro, ro,ret, /* ET following re */
/*let*/ lo, xl, xr, la, le, xa,let, lo, lo,let, /* ET following le */
};
enum bidi_action // possible actions
{
// primitives
IX = 0x100, // increment
XX = 0xF, // no-op
// actions
xxx = (XX << 4) + XX, // no-op
xIx = IX + xxx, // increment run
xxN = (XX << 4) + ON, // set current to N
xxE = (XX << 4) + EN, // set current to EN
xxA = (XX << 4) + AN, // set current to AN
xxR = (XX << 4) + R, // set current to R
xxL = (XX << 4) + L, // set current to L
Nxx = (ON << 4) + 0xF, // set run to neutral
Axx = (AN << 4) + 0xF, // set run to AN
ExE = (EN << 4) + EN, // set run to EN, set current to EN
NIx = (ON << 4) + 0xF + IX, // set run to N, increment
NxN = (ON << 4) + ON, // set run to N, set current to N
NxR = (ON << 4) + R, // set run to N, set current to R
NxE = (ON << 4) + EN, // set run to N, set current to EN
AxA = (AN << 4) + AN, // set run to AN, set current to AN
NxL = (ON << 4) + L, // set run to N, set current to L
LxL = (L << 4) + L, // set run to L, set current to L
};
int actionWeak[][10] =
{
// N,.. L, R, AN, EN, AL, NSM, CS,..ES, ET,
/*xa*/ xxx, xxx, xxx, xxx, xxA, xxR, xxR, xxN, xxN, xxN, /* arabic letter */
/*xr*/ xxx, xxx, xxx, xxx, xxE, xxR, xxR, xxN, xxN, xIx, /* right leter */
/*xl*/ xxx, xxx, xxx, xxx, xxL, xxR, xxL, xxN, xxN, xIx, /* left letter */
/*ao*/ xxx, xxx, xxx, xxx, xxA, xxR, xxN, xxN, xxN, xxN, /* arabic lett. foll by ON */
/*ro*/ xxx, xxx, xxx, xxx, xxE, xxR, xxN, xxN, xxN, xIx, /* right lett. foll by ON */
/*lo*/ xxx, xxx, xxx, xxx, xxL, xxR, xxN, xxN, xxN, xIx, /* left lett. foll by ON */
/*rt*/ Nxx, Nxx, Nxx, Nxx, ExE, NxR, xIx, NxN, NxN, xIx, /* ET following R */
/*lt*/ Nxx, Nxx, Nxx, Nxx, LxL, NxR, xIx, NxN, NxN, xIx, /* ET following L */
/*cn*/ xxx, xxx, xxx, xxx, xxA, xxR, xxA, xIx, xxN, xxN, /* EN, AN following AL */
/*ra*/ xxx, xxx, xxx, xxx, xxE, xxR, xxA, xIx, xxN, xIx, /* arabic number foll R */
/*re*/ xxx, xxx, xxx, xxx, xxE, xxR, xxE, xIx, xIx, xxE, /* european number foll R */
/*la*/ xxx, xxx, xxx, xxx, xxL, xxR, xxA, xIx, xxN, xIx, /* arabic number foll L */
/*le*/ xxx, xxx, xxx, xxx, xxL, xxR, xxL, xIx, xIx, xxL, /* european number foll L */
/*ac*/ Nxx, Nxx, Nxx, Axx, AxA, NxR, NxN, NxN, NxN, NxN, /* CS following cn */
/*rc*/ Nxx, Nxx, Nxx, Axx, NxE, NxR, NxN, NxN, NxN, NIx, /* CS following ra */
/*rs*/ Nxx, Nxx, Nxx, Nxx, ExE, NxR, NxN, NxN, NxN, NIx, /* CS,ES following re */
/*lc*/ Nxx, Nxx, Nxx, Axx, NxL, NxR, NxN, NxN, NxN, NIx, /* CS following la */
/*ls*/ Nxx, Nxx, Nxx, Nxx, LxL, NxR, NxN, NxN, NxN, NIx, /* CS,ES following le */
/*ret*/xxx, xxx, xxx, xxx, xxE, xxR, xxE, xxN, xxN, xxE, /* ET following re */
/*let*/xxx, xxx, xxx, xxx, xxL, xxR, xxL, xxN, xxN, xxL, /* ET following le */
};
int GetDeferredType(int action)
{
return (action >> 4) & 0xF;
}
int GetResolvedType(int action)
{
return action & 0xF;
}
/* Note on action table:
States can be of two kinds:
- Immediate Resolution State, where each input token
is resolved as soon as it is seen. These states havve
only single action codes (xxN) or the no-op (xxx)
for static input tokens.
- Deferred Resolution State, where input tokens either
either extend the run (xIx) or resolve its Type (e.g. Nxx).
Input classes are of three kinds
- Static Input Token, where the class of the token remains
unchanged on output (AN, L, N, R)
- Replaced Input Token, where the class of the token is
always replaced on output (AL, BN, NSM, CS, ES, ET)
- Conditional Input Token, where the class of the token is
changed on output in some but not all cases (EN)
Where tokens are subject to change, a double action
(e.g. NxA, or NxN) is _required_ after deferred states,
resolving both the deferred state and changing the current token.
These properties of the table are verified by assertions below.
This code is needed only during debugging and maintenance
*/
#if ASSERT_ENABLED
bool IsDeferredState(int state)
{
switch(state)
{
case rt: // this needs to be a deferred
case lt:
case ac:
case rc:
case rs:
case lc:
case ls:
return true;
}
return false;
}
bool IsModifiedClass(int cls)
{
switch(cls)
{
case AL:
case NSM:
case ES:
case CS:
case ET:
case EN: // sometimes 'modified' to EN
return true;
}
return false;
}
const int state_first = xa;
const int state_last = let;
const int cls_first = N;
const int cls_last = ET;
// Verify these properties of the tables
int VerifyTables()
{
int done = 1;
for (int cls = cls_first; cls <= cls_last; cls++)
{
for (int state = state_first; state <= state_last; state++)
{
int action= actionWeak[state][cls];
int nextstate = stateWeak[state][cls];
if (IX & action)
{
// make sure when we defer we get to a
// deferred state
ASSERT(IsDeferredState(nextstate));
// Make sure permanent classes are not deferred
ASSERT(IsModifiedClass(cls));
}
else
{
// make sure we are not deferring without
// incrementing a run
ASSERT(!IsDeferredState(nextstate));
// make sure modified classes are modified
if (IsModifiedClass(cls))
{
ASSERT(GetResolvedType(action) != XX);
}
else
{
ASSERT(GetResolvedType(action) == XX);
}
}
// if we are deferring, make sure things are resolved
if (IsDeferredState(state))
{
// Deferred states must increment or have deferred type
ASSERT(action == xIx || GetDeferredType(action) != XX);
}
else
{
ASSERT(GetDeferredType(action) == XX);
}
}
};
return done;
}
#endif
/*------------------------------------------------------------------------
Function: resolveWeak
Resolves the directionality of numeric and other weak character types
Implements rules X10 and W1-W6 of the Unicode Bidirectional Algorithm.
Input: Array of embedding levels
Character count
In/Out: Array of directional classes
Note: On input only these directional classes are expected
AL, HL, R, L, ON, BN, NSM, AN, EN, ES, ET, CS,
------------------------------------------------------------------------*/
void resolveWeak(int baselevel, int *pcls, int *plevel, int cch)
{
int state = odd(baselevel) ? xr : xl;
int cls;
int level = baselevel;
int cchRun = 0;
for (int ich = 0; ich < cch; ich++)
{
#if WINDOWS_UI < 1
#ifdef DEBUGGING
if (pcls[ich] > BN) {
fprintf(stdout, "error: pcls[%d] > BN (%d)\n", ich, pcls[ich]);
}
#endif
#endif
// ignore boundary neutrals
if (pcls[ich] == BN)
{
// must flatten levels unless at a level change;
plevel[ich] = level;
// lookahead for level changes
if (ich + 1 == cch && level != baselevel)
{
// have to fixup last BN before end of the loop, since
// its fix-upped value will be needed below the assert
pcls[ich] = EmbeddingDirection(level);
}
else if (ich + 1 < cch && level != plevel[ich+1] && pcls[ich+1] != BN)
{
// fixup LAST BN in front / after a level run to make
// it act like the SOR/EOR in rule X10
int newlevel = plevel[ich+1];
if (level > newlevel) {
newlevel = level;
}
plevel[ich] = newlevel;
// must match assigned level
pcls[ich] = EmbeddingDirection(newlevel);
level = plevel[ich+1];
}
else
{
// don't interrupt runs
if (cchRun)
{
cchRun++;
}
continue;
}
}
ASSERT(pcls[ich] <= BN);
cls = pcls[ich];
int action = actionWeak[state][cls];
// resolve the directionality for deferred runs
int clsRun = GetDeferredType(action);
if (clsRun != XX)
{
SetDeferredRun(pcls, cchRun, ich, clsRun);
cchRun = 0;
}
// resolve the directionality class at the current location
int clsNew = GetResolvedType(action);
if (clsNew != XX)
pcls[ich] = clsNew;
// increment a deferred run
if (IX & action)
cchRun++;
state = stateWeak[state][cls];
}
// resolve any deferred runs
// use the direction of the current level to emulate PDF
cls = EmbeddingDirection(level);
// resolve the directionality for deferred runs
int clsRun = GetDeferredType(actionWeak[state][cls]);
if (clsRun != XX)
SetDeferredRun(pcls, cchRun, ich, clsRun);
}
// === RESOLVE NEUTAL TYPES ==============================================
// action values
enum neutral_action
{
// action to resolve previous input
nL = L, // resolve EN to L
En = 3 << 4, // resolve neutrals run to embedding level direction
Rn = R << 4, // resolve neutrals run to strong right
Ln = L << 4, // resolved neutrals run to strong left
In = (1<<8), // increment count of deferred neutrals
LnL = (1<<4)+L, // set run and EN to L
};
int GetDeferredNeutrals(int action, int level)
{
action = (action >> 4) & 0xF;
if (action == (En >> 4))
return EmbeddingDirection(level);
else
return action;
}
int GetResolvedNeutrals(int action)
{
action = action & 0xF;
if (action == In)
return 0;
else
return action;
}
// state values
enum neutral_state
{
// new temporary class
r, // R and characters resolved to R
l, // L and characters resolved to L
rn, // N preceded by right
ln, // N preceded by left
a, // AN preceded by left (the abbrev 'la' is used up above)
na, // N preceeded by a
} ;
/*------------------------------------------------------------------------
Notes:
By rule W7, whenever a EN is 'dominated' by an L (including start of
run with embedding direction = L) it is resolved to, and further treated
as L.
This leads to the need for 'a' and 'na' states.
------------------------------------------------------------------------*/
int actionNeutrals[][5] =
{
// N, L, R, AN, EN, = cls
// state =
In, 0, 0, 0, 0, // r right
In, 0, 0, 0, L, // l left
In, En, Rn, Rn, Rn, // rn N preceded by right
In, Ln, En, En, LnL, // ln N preceded by left
In, 0, 0, 0, L, // a AN preceded by left
In, En, Rn, Rn, En, // na N preceded by a
} ;
int stateNeutrals[][5] =
{
// N, L, R, AN, EN = cls
// state =
rn, l, r, r, r, // r right
ln, l, r, a, l, // l left
rn, l, r, r, r, // rn N preceded by right
ln, l, r, a, l, // ln N preceded by left
na, l, r, a, l, // a AN preceded by left
na, l, r, a, l, // na N preceded by la
} ;
/*------------------------------------------------------------------------
Function: resolveNeutrals
Resolves the directionality of neutral character types.
Implements rules W7, N1 and N2 of the Unicode Bidi Algorithm.
Input: Array of embedding levels
Character count
Baselevel
In/Out: Array of directional classes
Note: On input only these directional classes are expected
R, L, N, AN, EN and BN
W8 resolves a number of ENs to L
------------------------------------------------------------------------*/
void resolveNeutrals(int baselevel, int *pcls, const int *plevel, int cch)
{
// the state at the start of text depends on the base level
int state = odd(baselevel) ? r : l;
int cls;
int cchRun = 0;
int level = baselevel;
for (int ich = 0; ich < cch; ich++)
{
// ignore boundary neutrals
if (pcls[ich] == BN)
{
// include in the count for a deferred run
if (cchRun)
cchRun++;
// skip any further processing
continue;
}
ASSERT(pcls[ich] < 5); // "Only N, L, R, AN, EN are allowed"
cls = pcls[ich];
int action = actionNeutrals[state][cls];
// resolve the directionality for deferred runs
int clsRun = GetDeferredNeutrals(action, level);
if (clsRun != N)
{
SetDeferredRun(pcls, cchRun, ich, clsRun);
cchRun = 0;
}
// resolve the directionality class at the current location
int clsNew = GetResolvedNeutrals(action);
if (clsNew != N)
pcls[ich] = clsNew;
if (In & action)
cchRun++;
state = stateNeutrals[state][cls];
level = plevel[ich];
}
// resolve any deferred runs
cls = EmbeddingDirection(level); // eor has type of current level
// resolve the directionality for deferred runs
int clsRun = GetDeferredNeutrals(actionNeutrals[state][cls], level);
if (clsRun != N)
SetDeferredRun(pcls, cchRun, ich, clsRun);
}
// === RESOLVE IMPLLICIT =================================================
/*------------------------------------------------------------------------
Function: resolveImplicit
Recursively resolves implicit embedding levels.
Implements rules I1 and I2 of the Unicode Bidirectional Algorithm.
Input: Array of direction classes
Character count
Base level
In/Out: Array of embedding levels
Note: levels may exceed 15 on output.
Accepted subset of direction classes
R, L, AN, EN
------------------------------------------------------------------------*/
int addLevel[][4] =
{
// L, R, AN, EN = cls
// level =
/* even */ 0, 1, 2, 2, // EVEN
/* odd */ 1, 0, 1, 1, // ODD
};
void resolveImplicit(const int * pcls, int * plevel, int cch)
{
for (int ich = 0; ich < cch; ich++)
{
// cannot resolve bn here, since some bn were resolved to strong
// types in resolveWeak. To remove these we need the original
// types, which are available again in resolveWhiteSpace
if (pcls[ich] == BN)
{
continue;
}
ASSERT(pcls[ich] > 0); // "No Neutrals allowed to survive here."
ASSERT(pcls[ich] < 5); // "Out of range."
plevel[ich] += addLevel[odd(plevel[ich])][pcls[ich] - 1];
}
}
// === REORDER ===========================================================
/*------------------------------------------------------------------------
Function: resolveLines
Breaks a paragraph into lines
Input: Character count
Array of line break flags
In/Out: Array of characters
Returns the count of characters on the first line
Note: This function only breaks lines at hard line breaks. Other
line breaks can be passed in. If pbrk[n] is true, then a break
occurs after the character in pszInput[n]. Breaks before the first
character are not allowed.
------------------------------------------------------------------------*/
int resolveLines(TCHAR * pszInput, bool * pbrk, int cch)
{
// skip characters not of type LS
for(int ich = 0; ich < cch; ich++)
{
if (pszInput[ich] == chLS || (pbrk && pbrk[ich]))
{
ich++;
break;
}
}
return ich;
}
/*------------------------------------------------------------------------
Function: resolveWhiteSpace
Resolves levels for WS and S
Implements rule L1 of the Unicode bidi Algorithm.
Input: Base embedding level
Character count
Array of direction classes (for one line of text)
In/Out: Array of embedding levels (for one line of text)
Note: this should be applied a line at a time. The default driver
code supplied in this file assumes a single line of text; for
a real implementation, cch and the initial pointer values
would have to be adjusted.
------------------------------------------------------------------------*/
void resolveWhitespace(int baselevel, const int *pcls, int *plevel,
int cch)
{
int cchrun = 0;
int oldlevel = baselevel;
for (int ich = 0; ich < cch; ich++)
{
switch(pcls[ich])
{
default:
cchrun = 0; // any other character breaks the run
break;
case WS:
cchrun++;
break;
case RLE:
case LRE:
case LRO:
case RLO:
case PDF:
case BN:
plevel[ich] = oldlevel;
cchrun++;
break;
case S:
case B:
// reset levels for WS before eot
SetDeferredRun(plevel, cchrun, ich, baselevel);
cchrun = 0;
plevel[ich] = baselevel;
break;
}
oldlevel = plevel[ich];
}
// reset level before eot
SetDeferredRun(plevel, cchrun, ich, baselevel);
}
/*------------------------------------------------------------------------
Functions: reorder/reorderLevel
Recursively reorders the display string
"From the highest level down, reverse all characters at that level and
higher, down to the lowest odd level"
Implements rule L2 of the Unicode bidi Algorithm.
Input: Array of embedding levels
Character count
Flag enabling reversal (set to false by initial caller)
In/Out: Text to reorder
Note: levels may exceed 15 resp. 61 on input.
Rule L3 - reorder combining marks is not implemented here
Rule L4 - glyph mirroring is implemented as a display option below
Note: this should be applied a line at a time
-------------------------------------------------------------------------*/
int reorderLevel(int level, LPTSTR pszText, const int * plevel, int cch,
bool fReverse = false)
{
// true as soon as first odd level encountered
fReverse = fReverse || odd(level);
for (int ich = 0; ich < cch; ich++)
{
if (plevel[ich] < level)
{
break;
}
else if (plevel[ich] > level)
{
ich += reorderLevel(level + 1, pszText + ich, plevel + ich,
cch - ich, fReverse) - 1;
}
}
if (fReverse)
{
reverse(pszText, ich);
}
return ich;
}
int reorder(int baselevel, LPTSTR pszText, const int * plevel, int cch)
{
int ich = 0;
while (ich < cch)
{
ich += reorderLevel(baselevel, pszText + ich, plevel + ich,
cch - ich);
}
return ich;
}
// === DISPLAY OPTIONS ================================================
/*-----------------------------------------------------------------------
Function: mirror
Crudely implements rule L4 of the Unicode Bidirectional Algorithm
Demonstrate mirrored brackets, braces and parens
Input: Array of levels
Count of characters
In/Out: Array of characters (should be array of glyph ids)
Note;
A full implementation would need to substitute mirrored glyphs even
for characters that are not paired (e.g. integral sign).
-----------------------------------------------------------------------*/
void mirror(LPTSTR pszInput, const int * plevel, int cch)
{
for (int ich = 0; ich < cch; ich ++)
{
if (!odd(plevel[ich]))
continue;
if (pszInput[ich] == '<')
{
pszInput[ich] = '>';
}
else if (pszInput[ich] == '>')
{
pszInput[ich] = '<';
}
else if (pszInput[ich] == ')')
{
pszInput[ich] = '(';
}
else if (pszInput[ich] == '(')
{
pszInput[ich] = ')';
}
}
}
/*-----------------------------------------------------------------------
Function: clean
remove formatting codes
In/Out: Array of characters
Count of characters
Note;
This function can be used to remove formatting codes so the
ordering of the string can be compared to implementations that
remove formatting codes. This implementation is limited to the
pseudo alphabet used for the demo version.
-----------------------------------------------------------------------*/
int clean(LPTSTR pszInput, int cch)
{
int cchMove = 0;
for (int ich = 0; ich < cch; ich ++)
{
int ch = pszInput[ich];
switch (ch)
{
default:
if (pszInput[ich] < 0x20)
{
cchMove++;
}
else
{
pszInput[ich - cchMove] = pszInput[ich];
}
break;
case chRLO:
case chLRO:
case chRLE:
case chLRE:
case chPDF:
case chBN:
cchMove++;
break;
}
}
pszInput[ich - cchMove] = 0;
return ich - cchMove;
}
// === BIDI INTERFACE FUNCTIONS ========================================
/*------------------------------------------------------------------------
Function: BidiLines
Implements the Line-by-Line phases of the Unicode Bidi Algorithm
Input: Count of characters
Flag (Mirror output if true)
Optional: Array of flags, true for last character on each line
Inp/Out: Input text
Array of character directions
Array of levels
Note: See resolveLines for information how this function deals with line breaks
------------------------------------------------------------------------*/
void BidiLines(int baselevel, TCHAR * pszLine, int * pclsLine,
int * plevelLine, int cchPara, int fMirror, bool * pbrk)
{
int cchLine = 0;
do
{
// break lines at LS
cchLine = resolveLines(pszLine, pbrk, cchPara);
// resolve whitespace
resolveWhitespace(baselevel, pclsLine, plevelLine, cchLine);
if (fMirror)
{
mirror(pszLine, plevelLine, cchLine);
}
// reorder each line in place
reorder(baselevel, pszLine, plevelLine, cchLine);
pszLine += cchLine;
plevelLine += cchLine;
pbrk += pbrk ? cchLine : 0;
pclsLine += cchLine;
cchPara -= cchLine;
} while (cchPara);
}
/*------------------------------------------------------------------------
Function: BidiParagraph
Implements the per paragraph phases of the Unicode Bidi Algorithm
Input:
Count of characters
Inp/Out: Input text
Base paragraph level (negative value on input means implicit)
Array of character directions
Array of levels
Returns: The number of input characters processed for this paragraph
Note: This function is not called by the demo code in this file, but
provided here for completeness. It has been tested by being
used in the verfication code.
------------------------------------------------------------------------*/
int BidiParagraph(int &baselevel, int * types, int * levels, int cch)
{
// set baselevel
if (baselevel < 0)
baselevel = baseLevel(types, cch);
// change B into BN and return length including
int cchPara = resolveParagraphs(types, cch);
// resolve explicit
resolveExplicit(baselevel, N, types, levels, cchPara);
// resolve weak
resolveWeak(baselevel, types, levels, cchPara);
// resolve neutrals
resolveNeutrals(baselevel,types, levels, cchPara);
// resolveImplicit
resolveImplicit(types, levels, cchPara);
// return the part of the input processed so far
return cchPara;
}
#if WINDOWS_UI > 0
// === BIDI MAIN FUNCTION ================================================
#define MAX_CCH 256
void ShowInputTypes(HWND hwndDlg, int idc, LPTSTR pszInput, int cch)
{
TCHAR pszTypes[MAX_CCH];
for (int ich = 0; ich < cch; ich++)
{
pszTypes[ich] = CharFromTypes[ClassFromChWS(pszInput[ich])];
}
pszTypes[ich] = 0;
SetDlgItemText(hwndDlg, idc, pszTypes);
}
void ShowTypes(HWND hwndDlg, int idc, int * types, int cch)
{
TCHAR pszTypes[MAX_CCH];
for (int ich = 0; ich < cch; ich++)
{
pszTypes[ich] = CharFromTypes[types[ich]];
}
pszTypes[ich] = 0;
SetDlgItemText(hwndDlg, idc, pszTypes);
}
void ShowLevels(HWND hwndDlg, int idc, int * levels, int cch)
{
#if DEMO
// do nothing if levels are not limited to 15 as for debugging
// since we can't show 0-61 in a single character
TCHAR pszLevel[MAX_CCH];
for (int ich = 0; ich < cch; ich++)
{
pszLevel[ich] = CharFromLevel[levels[ich]];
}
pszLevel[ich] = 0;
SetDlgItemText(hwndDlg, idc, pszLevel);
#else
// squelch compiler warnings
idc; hwndDlg; levels; cch;
#endif
}
/*------------------------------------------------------------------------
Function: BidiDemo
Implements the Unicode Bidi Algorithm and drives display of results
Input: Handle to dialog
Note: directly reads/writes to fields in the dialog, limit 256 chars
------------------------------------------------------------------------*/
void BidiDemo(HWND hwndDlg)
{
// verify the tables once
#if DEBUGGING
#if WINDOWS_UI ==2
static int check = VerifyTables(); // ASSERT must be defind to enable this
#endif
#endif
TCHAR pszInput[MAX_CCH];
int types[MAX_CCH];
int levels[MAX_CCH];
// read input string
int cch = GetDlgItemText(hwndDlg, IDC_INPUT, pszInput, MAX_CCH);
// assign directional types
classify(pszInput, types, cch);
ShowInputTypes(hwndDlg, IDC_TYPES, pszInput, cch);
// limit text to first paragraph
cch = resolveParagraphs(types, cch);
// set base level and compute character types
int baselevel = GetDlgItemInt(hwndDlg, IDC_BASELEVEL, 0, 0);
if (IsDlgButtonChecked(hwndDlg, IDC_IMPLICIT))
{
baselevel = baseLevel(types, cch);
SetDlgItemInt(hwndDlg, IDC_BASELEVEL, baselevel, 0);
}
// resolve explicit
resolveExplicit(baselevel, N, types, levels, cch);
ShowLevels(hwndDlg, IDC_EX_LEVEL, levels, cch);
ShowTypes(hwndDlg, IDC_X_TYPES, types, cch);
// resolve weak
resolveWeak(baselevel, types, levels, cch);
ShowTypes(hwndDlg, IDC_W_TYPES, types, cch);
// resolve neutrals
resolveNeutrals(baselevel,types, levels, cch);
ShowTypes(hwndDlg, IDC_N_TYPES, types, cch);
// resolveImplicit
resolveImplicit(types, levels, cch);
// assign directional types to whitespace
classify(pszInput, types, cch, true);
// At this point, the paragraph is broken into lines
// This sample only supports hard line breaks (LS)
int fMirror = IsDlgButtonChecked(hwndDlg, IDC_MIRROR);
BidiLines(baselevel, pszInput, types, levels, cch, fMirror);
// report results
ShowLevels(hwndDlg, IDC_IM_LEVEL, levels, cch);
if (IsDlgButtonChecked(hwndDlg, IDC_CLEAN))
{
cch = clean(pszInput, cch);
}
// write display string
SetDlgItemText(hwndDlg, IDC_DISPL, pszInput);
}
// insert a special code into the edit field at the selection
void InsertAtSelection(HWND hwndDlg, TCHAR chFormat, int ichStart,
int ichEnd)
{
TCHAR pszInput[MAX_CCH];
TCHAR pszNew[MAX_CCH];
// read input string
int cch = GetDlgItemText(hwndDlg, IDC_INPUT, pszInput, MAX_CCH);
// no selection
if (ichEnd < ichStart || ichStart > cch)
return;
// insert RLM or LRM
lstrcpyn(pszNew, pszInput, ichStart + 1);
pszNew[ichStart] = chFormat;
lstrcpyn(pszNew + ichStart + 1, pszInput + ichStart,
cch - ichStart + 1);
// write formatted string
SetDlgItemText(hwndDlg, IDC_INPUT, pszNew);
// get ready to accept more typed input
SetFocus(GetDlgItem(hwndDlg, IDC_INPUT));
ichStart++;
SendDlgItemMessage(hwndDlg, IDC_INPUT, EM_SETSEL,
(LPARAM) ichStart, (WPARAM) ichStart);
}
// embed/override the selection by bracketing with explicit controls
void FormatSelection(HWND hwndDlg, TCHAR chFormat, int ichStart,
int ichEnd)
{
TCHAR pszInput[MAX_CCH];
TCHAR pszNew[MAX_CCH];
// read input string
int cch = GetDlgItemText(hwndDlg, IDC_INPUT, pszInput, MAX_CCH);
// no selection
if (ichEnd < ichStart || ichStart > cch)
return;
// embed or override the selection by bracketing with format
// character and PDF
lstrcpyn(pszNew, pszInput, ichStart + 1);
pszNew[ichStart] = chFormat;
lstrcpyn(pszNew + ichStart + 1, pszInput + ichStart,
ichEnd - ichStart + 1);
pszNew[ichEnd + 1] = chPDF;
lstrcpyn(pszNew + ichEnd + 2, pszInput + ichEnd, cch - ichEnd + 1);
// write formatted string
SetDlgItemText(hwndDlg, IDC_INPUT, pszNew);
// get ready to accept more typed input
SetFocus(GetDlgItem(hwndDlg, IDC_INPUT));
ichEnd+=2;
SendDlgItemMessage(hwndDlg, IDC_INPUT, EM_SETSEL,
(LPARAM) ichStart, (WPARAM) ichEnd);
}
#if WINDOWS_UI == 2
// For private build, this is an ordinary modeless dialog
BOOL CALLBACK BidiDlgProc(HWND hwndDlg, UINT message, WPARAM wParam,
LPARAM lParam)
{
static HFONT hfontDlg;
static int ichStart =0;
static int ichEnd = 0;
static PDWORD pcwndBidi = 0;
switch (message)
{
case WM_INITDIALOG:
{
// initialize dialog
SetDlgItemText(hwndDlg, IDC_LEGEND, legend);
CheckDlgButton(hwndDlg, IDC_MIRROR, TRUE);
CheckDlgButton(hwndDlg, IDC_IMPLICIT, TRUE);
#ifdef _WINDOW_H_
CWindow winDlg(hwndDlg);
winDlg.CenterAbove( GetWindow(hwndDlg,GW_OWNER));
#endif
hfontDlg = CreateFont(-14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
FIXED_PITCH | FF_MODERN, TEXT("Lucida Console"));
SendMessage (GetDlgItem (hwndDlg, IDC_LEGEND), WM_SETFONT, (UINT)hfontDlg, TRUE);
pcwndBidi = (PDWORD) lParam;
if (pcwndBidi)
(*pcwndBidi)++;
return TRUE;
}
// ... continued after #endif
#else
// For standalone (WINDOWS_UI == 1) the dialog is run as a main window
// requiring some difference in initialization code and message handling
// helper function to initialize the explanation window
BOOL CALLBACK SetLegendProc(HWND hwndChild, LPARAM lParam)
{
LONG id = GetWindowLong(hwndChild, GWL_ID);
if (id == IDC_LEGEND)
{
SendMessage(hwndChild, (UINT) WM_SETTEXT, (WPARAM) 0, (LPARAM) lParam);
return FALSE; // done
}
return TRUE; // continue looking
}
#pragma message("compiling standalone bidi dialog")
LRESULT CALLBACK BidiWndProc(HWND hwndDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
static HFONT hfontDlg;
static int ichStart =0;
static int ichEnd = 0;
switch (message)
{
case WM_SHOWWINDOW:
hfontDlg = CreateFont(-14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
FIXED_PITCH | FF_MODERN, TEXT("Lucida Console"));
SendMessage (GetDlgItem (hwndDlg, IDC_LEGEND), WM_SETFONT, (UINT)hfontDlg, TRUE);
CheckDlgButton(hwndDlg, IDC_MIRROR, TRUE);
CheckDlgButton(hwndDlg, IDC_IMPLICIT, TRUE);
// initialize explanation window
EnumChildWindows(hwndDlg, SetLegendProc, (LPARAM) legend);
return 0;
break;
case WM_DESTROY:
DeleteObject (hfontDlg);
PostQuitMessage(0);
return 0;
#endif
case WM_COMMAND:
{
int cmd = GET_WM_COMMAND_CMD(wParam, lParam);
int idc = GET_WM_COMMAND_ID(wParam, lParam);
switch (idc) //Command ID
{
case IDC_BASELEVEL:
if (!IsDlgButtonChecked(hwndDlg,IDC_IMPLICIT))
{
SendDlgItemMessage(hwndDlg, IDC_INPUT, EM_GETSEL,
(LPARAM) &ichStart, (WPARAM) &ichEnd);
BidiDemo(hwndDlg);
}
break;
// fall through causes display to update for these controls
case IDC_IMPLICIT:
SendDlgItemMessage(hwndDlg, IDC_BASELEVEL, EM_SETREADONLY,
IsDlgButtonChecked(hwndDlg,IDC_IMPLICIT), 0);
// FALL THROUGH
case IDC_INPUT:
if (idc == IDC_INPUT && cmd != EN_CHANGE)
break;
// FALL THROUGH
case IDC_CLEAN:
case IDC_MIRROR:
SendDlgItemMessage(hwndDlg, IDC_INPUT, EM_GETSEL,
(LPARAM) &ichStart, (WPARAM) &ichEnd);
BidiDemo(hwndDlg);
break;
case IDC_RLE:
FormatSelection(hwndDlg, chRLE, ichStart, ichEnd);
break;
case IDC_LRE:
FormatSelection(hwndDlg, chLRE, ichStart, ichEnd);
break;
case IDC_RLO:
FormatSelection(hwndDlg, chRLO, ichStart, ichEnd);
break;
case IDC_LRO:
FormatSelection(hwndDlg, chLRO, ichStart, ichEnd);
break;
case IDC_RLM:
InsertAtSelection(hwndDlg, chRLM, ichStart, ichEnd);
break;
case IDC_LRM:
InsertAtSelection(hwndDlg, chLRM, ichStart, ichEnd);
break;
case IDC_LS:
InsertAtSelection(hwndDlg, chLS, ichStart, ichEnd);
break;
#if WINDOWS_UI == 2
case IDOK: // "Close"
case IDCANCEL:
// pass either IDOK or IDCANCEL to ENDDIALOG
EndDialog(hwndDlg, GET_WM_COMMAND_ID(wParam, lParam));
DeleteObject (hfontDlg);
CWindow::SetModelessDlg(0);
if (pcwndBidi)
(*pcwndBidi)--;
return TRUE;
#endif
}
}
break;
}
#if WINDOWS_UI == 1
return DefWindowProc(hwndDlg, message, wParam, lParam);
#else
return FALSE ;
#endif
// squelch compiler warnings
lParam;
}
#else
#pragma message("compiling functions for commandline version")
// ===== FUNCTIONS FOR COMMAND LINE VERSION ==============================
#include <stdlib.h>
#include <string.h>
// An alternate CharFromTypes array may be needed to use with the command
// line version
#define MAX_CCH 256
void ShowInputTypes(FILE* f, LPTSTR pszInput, int cch)
{
TCHAR pszTypes[MAX_CCH+1];
for (int ich = 0; ich < cch; ich++)
{
pszTypes[ich] = CharFromTypes[ClassFromChWS(pszInput[ich])];
}
pszTypes[ich] = 0;
fprintf(f, pszTypes);
}
void ShowTypes(FILE* f, int * types, int cch)
{
TCHAR pszTypes[MAX_CCH+1];
for (int ich = 0; ich < cch; ich++)
{
pszTypes[ich] = CharFromTypes[types[ich]];
}
pszTypes[ich] = 0;
fprintf(f, pszTypes);
}
void ShowLevels(FILE* f, int * levels, int cch)
{
#if DEMO
// do nothing if levels are not limited to 15 as for debugging
// since we can't show 0-61 in a single character
TCHAR pszLevel[MAX_CCH+1];
for (int ich = 0; ich < cch; ich++)
{
pszLevel[ich] = CharFromLevel[levels[ich]];
}
pszLevel[ich] = 0;
fprintf(f, pszLevel);
#else
// squelch compiler warnings
f; levels; cch;
#endif
}
void usage(char *s)
{
printf("Usage: %s [-verbose] [-nomirror] [-level #] [-clean] strings...\n", s);
printf("\t-verbose = verbose debugging output.\n");
printf("\t-level # = specify # as the base level.\n");
printf("\t-nomirror = refrain from glyph mirroring.\n");
printf("\t-clean = clean up the result.\n");
printf("\tOptions affect all subsequent arguments.\n");
printf("\tAll other arguments are interpreted as strings to process.\n");
}
int main(int argc, char** argv)
{
int realArg = 0;
int doMirror = 1;
int doClean = 0;
int doLevel = 1;
int baselevel = 0;
int beVerbose = 0;
FILE* f = stdout;
if (argc == 1)
{
usage(argv[0]); exit(0);
}
for (int i = 1; i < argc; ++i)
{
if (doLevel == -1)
{
baselevel = atoi(argv[i]);
doLevel = 0;
continue;
}
else if (strcmp(argv[i], "-verbose") == 0)
{
beVerbose = 1;
continue;
}
else if (strcmp(argv[i], "-nomirror") == 0)
{
doMirror = 0;
continue;
}
else if (strcmp(argv[i], "-clean") == 0)
{
doClean = 1;
continue;
}
else if (strcmp(argv[i], "-level") == 0)
{
if (argc - 1 == i)
{
usage(argv[0]); exit(0);
}
doLevel = -1;
continue;
}
else
{
++realArg;
}
TCHAR pszInput[MAX_CCH+1];
int cch = strlen(argv[i]);
if (cch > MAX_CCH) cch = MAX_CCH;
strncpy(pszInput, argv[i], cch);
pszInput[cch] = 0;
fprintf(f, "Input %2d: %s\n", realArg, pszInput);
int types[MAX_CCH];
int levels[MAX_CCH];
// assign directional types
classify(pszInput, types, cch);
if (beVerbose)
{
fprintf(f, "Input Types: ");
ShowInputTypes(f, pszInput, cch); fprintf(f, "\n");
}
// limit text to first block
cch = resolveParagraphs(types, cch);
// set base level
if (doLevel)
baselevel = baseLevel(types, cch);
if (beVerbose)
{
fprintf(f, "Base Level : %d\n", baselevel);
}
// resolve explicit
resolveExplicit(baselevel, N, types, levels, cch);
if (beVerbose)
{
fprintf(f, "Levels (A) : ");
ShowLevels(f, levels, cch); fprintf(f, "\n");
}
// resolve weak
resolveWeak(baselevel, types, levels, cch);
if (beVerbose)
{
fprintf(f, "Types (A) : ");
ShowTypes(f, types, cch); fprintf(f, "\n");
}
// resolve neutrals
resolveNeutrals(baselevel,types, levels, cch);
if (beVerbose)
{
fprintf(f, "Types (B) : ");
ShowTypes(f, types, cch); fprintf(f, "\n");
}
// resolveImplicit
resolveImplicit(types, levels, cch);
if (beVerbose)
{
fprintf(f, "Levels (B) : ");
ShowLevels(f, levels, cch); fprintf(f, "\n");
}
// assign directional types again, but for WS, S this time
classify(pszInput, types, cch, true);
BidiLines(baselevel, pszInput, types, levels, cch, doMirror);
if (doClean)
{
cch = clean(pszInput, cch);
}
fprintf(f, "Output %2d: %s\n\n", realArg, pszInput);
}
return 0;
}
#endif // WINDOWS_UI
//[EOF]