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authorwolfbeast <mcwerewolf@gmail.com>2018-02-04 15:23:27 +0100
committerwolfbeast <mcwerewolf@gmail.com>2018-02-04 15:23:27 +0100
commit3ef4f63ec257cf90ad4bf8695a1e4e291f811af2 (patch)
treea250561efd62b85afa60738eec1cf3184d9ea499 /gfx/graphite2/src/Bidi.cpp
parentfeeb4327304db5af1c4aa7f77c082bb6527eef5b (diff)
parenta47a037ec9052bf1707be10ba5140226f939eb60 (diff)
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Merge branch 'ported-moebius'
Diffstat (limited to 'gfx/graphite2/src/Bidi.cpp')
-rw-r--r--gfx/graphite2/src/Bidi.cpp826
1 files changed, 0 insertions, 826 deletions
diff --git a/gfx/graphite2/src/Bidi.cpp b/gfx/graphite2/src/Bidi.cpp
deleted file mode 100644
index 48ec2ebfc..000000000
--- a/gfx/graphite2/src/Bidi.cpp
+++ /dev/null
@@ -1,826 +0,0 @@
-/* GRAPHITE2 LICENSING
-
- Copyright 2011, SIL International
- All rights reserved.
-
- This library is free software; you can redistribute it and/or modify
- it under the terms of the GNU Lesser General Public License as published
- by the Free Software Foundation; either version 2.1 of License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should also have received a copy of the GNU Lesser General Public
- License along with this library in the file named "LICENSE".
- If not, write to the Free Software Foundation, 51 Franklin Street,
- suite 500, Boston, MA 02110-1335, USA or visit their web page on the
- internet at http://www.fsf.org/licenses/lgpl.html.
-
-Alternatively, the contents of this file may be used under the terms of the
-Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public
-License, as published by the Free Software Foundation, either version 2
-of the License or (at your option) any later version.
-*/
-#include "inc/Main.h"
-#include "inc/Slot.h"
-#include "inc/Segment.h"
-#include "inc/Bidi.h"
-
-using namespace graphite2;
-
-enum DirCode { // Hungarian: dirc
- Unk = -1,
- N = 0, // other neutrals (default) - ON
- L = 1, // left-to-right, strong - L
- R = 2, // right-to-left, strong - R
- AL = 3, // Arabic letter, right-to-left, strong, AR
- EN = 4, // European number, left-to-right, weak - EN
- EUS = 5, // European separator, left-to-right, weak - ES
- ET = 6, // European number terminator, left-to-right, weak - ET
- AN = 7, // Arabic number, left-to-right, weak - AN
- CUS = 8, // Common number separator, left-to-right, weak - CS
- WS = 9, // white space, neutral - WS
- BN = 10, // boundary neutral - BN
-
- LRO = 11, // LTR override
- RLO = 12, // RTL override
- LRE = 13, // LTR embedding
- RLE = 14, // RTL embedding
- PDF = 15, // pop directional format
- NSM = 16, // non-space mark
- LRI = 17, // LRI isolate
- RLI = 18, // RLI isolate
- FSI = 19, // FSI isolate
- PDI = 20, // pop isolate
- OPP = 21, // opening paired parenthesis
- CPP = 22, // closing paired parenthesis
-
- ON = N
-};
-
-enum DirMask {
- WSflag = int8(1 << 7), // keep track of WS for eos handling
- WSMask = int8(~(1 << 7))
-};
-
-inline uint8 BaseClass(Slot *s) { return s->getBidiClass() & WSMask; }
-
-unsigned int bidi_class_map[] = { 0, 1, 2, 5, 4, 8, 9, 3, 7, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0 };
-// Algorithms based on Unicode reference standard code. Thanks Asmus Freitag.
-
-void resolveWeak(Slot *start, int sos, int eos);
-void resolveNeutrals(Slot *s, int baseLevel, int sos, int eos);
-void processParens(Slot *s, Segment *seg, uint8 aMirror, int level, BracketPairStack &stack);
-
-inline int calc_base_level(Slot *s)
-{
- int count = 0;
- for ( ; s; s = s->next())
- {
- int cls = s->getBidiClass();
- if (count)
- {
- switch(cls)
- {
- case LRI :
- case RLI :
- case FSI :
- ++count;
- break;
- case PDI :
- --count;
- }
- }
- else
- {
- switch(cls)
- {
- case L :
- return 0;
- case R :
- case AL :
- return 1;
- case LRI :
- case RLI :
- case FSI :
- ++count;
- }
- }
- }
- return 0;
-}
-
-// inline or not?
-void do_resolves(Slot *start, int level, int sos, int eos, int &bmask, Segment *seg, uint8 aMirror, BracketPairStack &stack)
-{
- if (bmask & 0x1F1178)
- resolveWeak(start, sos, eos);
- if (bmask & 0x200000)
- processParens(start, seg, aMirror, level, stack);
- if (bmask & 0x7E0361)
- resolveNeutrals(start, level, sos, eos);
- bmask = 0;
-}
-
-enum maxs
-{
- MAX_LEVEL = 125,
-};
-
-// returns where we are up to in processing
-Slot *process_bidi(Slot *start, int level, int prelevel, int &nextLevel, int dirover, int isol, int &cisol, int &isolerr, int &embederr, int init, Segment *seg, uint8 aMirror, BracketPairStack &bstack)
-{
- int bmask = 0;
- Slot *s = start;
- Slot *slast = start;
- Slot *scurr = 0;
- Slot *stemp;
- int lnextLevel = nextLevel;
- int newLevel;
- int empty = 1;
- for ( ; s; s = s ? s->next() : s)
- {
- int cls = s->getBidiClass();
- bmask |= (1 << cls);
- s->setBidiLevel(level);
- // we keep s->prev() pointing backwards for PDI repeating
-
- switch (cls)
- {
- case BN :
- if (slast == s) slast = s->next(); // ignore if at front of text
- continue;
- case LRE :
- case LRO :
- case RLE :
- case RLO :
- switch (cls)
- {
- case LRE :
- case LRO :
- newLevel = level + (level & 1 ? 1 : 2);
- break;
- case RLE :
- case RLO :
- newLevel = level + (level & 1 ? 2 : 1);
- break;
- }
- s->setBidiClass(BN);
- if (isolerr || newLevel > MAX_LEVEL || embederr)
- {
- if (!isolerr) ++embederr;
- break;
- }
- stemp = scurr;
- if (scurr)
- scurr->prev(0); // don't include control in string
- lnextLevel = newLevel;
- scurr = s;
- s->setBidiLevel(newLevel); // to make it vanish
- // recurse for the new subsequence. A sequence only contains text at the same level
- s = process_bidi(s->next(), newLevel, level, lnextLevel, cls < LRE, 0, cisol, isolerr, embederr, 0, seg, aMirror, bstack);
- // s points at PDF or end of sequence
- // try to keep extending the run and not process it until we have to
- if (lnextLevel != level || !s) // if the subsequence really had something in it, or we are at the end of the run
- {
- if (slast != scurr) // process the run now, don't try to extend it
- {
- // process text preceeding embedding
- do_resolves(slast, level, (prelevel > level ? prelevel : level) & 1, lnextLevel & 1, bmask, seg, aMirror, bstack);
- empty = 0;
- nextLevel = level;
- }
- else if (lnextLevel != level) // the subsequence had something
- {
- empty = 0; // so we aren't empty either
- nextLevel = lnextLevel; // but since we really are empty, pass back our level from the subsequence
- }
- if (s) // if still more to process
- {
- prelevel = lnextLevel; // future text starts out with sos of the higher subsequence
- lnextLevel = level; // and eos is our level
- }
- slast = s ? s->next() : s;
- }
- else if (stemp)
- stemp->prev(s);
- break;
-
- case PDF :
- s->setBidiClass(BN);
- s->prev(0); // unstitch us since we skip final stitching code when we return
- if (isol || isolerr || init) // boundary error conditions
- break;
- if (embederr)
- {
- --embederr;
- break;
- }
- if (slast != s)
- {
- scurr->prev(0); // if slast, then scurr. Terminate before here
- do_resolves(slast, level, level & 1, level & 1, bmask, seg, aMirror, bstack);
- empty = 0;
- }
- if (empty)
- {
- nextLevel = prelevel; // no contents? set our level to that of parent
- s->setBidiLevel(prelevel);
- }
- return s;
-
- case FSI :
- case LRI :
- case RLI :
- switch (cls)
- {
- case FSI :
- if (calc_base_level(s->next()))
- newLevel = level + (level & 1 ? 2 : 1);
- else
- newLevel = level + (level & 1 ? 1 : 2);
- break;
- case LRI :
- newLevel = level + (level & 1 ? 1 : 2);
- break;
- case RLI :
- newLevel = level + (level & 1 ? 2 : 1);
- break;
- }
- if (newLevel > MAX_LEVEL || isolerr)
- {
- ++isolerr;
- s->setBidiClass(ON | WSflag);
- break;
- }
- ++cisol;
- if (scurr) scurr->prev(s);
- scurr = s; // include FSI
- lnextLevel = newLevel;
- // recurse for the new sub sequence
- s = process_bidi(s->next(), newLevel, newLevel, lnextLevel, 0, 1, cisol, isolerr, embederr, 0, seg, aMirror, bstack);
- // s points at PDI
- if (s)
- {
- bmask |= 1 << BaseClass(s); // include the PDI in the mask
- s->setBidiLevel(level); // reset its level to our level
- }
- lnextLevel = level;
- break;
-
- case PDI :
- if (isolerr)
- {
- --isolerr;
- s->setBidiClass(ON | WSflag);
- break;
- }
- if (init || !cisol)
- {
- s->setBidiClass(ON | WSflag);
- break;
- }
- embederr = 0;
- if (!isol) // we are in an embedded subsequence, we have to return through all those
- {
- if (empty) // if empty, reset the level to tell embedded parent
- nextLevel = prelevel;
- return s->prev(); // keep working up the stack pointing at this PDI until we get to an isolate entry
- }
- else // we are terminating an isolate sequence
- {
- if (slast != s) // process any remaining content in this subseqence
- {
- scurr->prev(0);
- do_resolves(slast, level, prelevel & 1, level & 1, bmask, seg, aMirror, bstack);
- }
- --cisol; // pop the isol sequence from the stack
- return s;
- }
-
- default :
- if (dirover)
- s->setBidiClass((level & 1 ? R : L) | (WSflag * (cls == WS)));
- }
- if (s) s->prev(0); // unstitch us
- if (scurr) // stitch in text for processing
- scurr->prev(s);
- scurr = s; // add us to text to process
- }
- if (slast != s)
- {
- do_resolves(slast, level, (level > prelevel ? level : prelevel) & 1, lnextLevel & 1, bmask, seg, aMirror, bstack);
- empty = 0;
- }
- if (empty || isol)
- nextLevel = prelevel;
- return s;
-}
-
-// === 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
-} ;
-
-const bidi_state 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
-};
-
-
-const bidi_action 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 */ },
-};
-
-inline uint8 GetDeferredType(bidi_action a) { return (a >> 4) & 0xF; }
-inline uint8 GetResolvedType(bidi_action a) { return a & 0xF; }
-inline DirCode EmbeddingDirection(int l) { return l & 1 ? R : L; }
-
-// Neutrals
-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
-};
-
-// ->prev() here means ->next()
-void SetDeferredRunClass(Slot *s, Slot *sRun, int nval)
-{
- if (!sRun || s == sRun) return;
- for (Slot *p = sRun; p != s; p = p->prev())
- if (p->getBidiClass() == WS) p->setBidiClass(nval | WSflag);
- else if (BaseClass(p) != BN) p->setBidiClass(nval | (p->getBidiClass() & WSflag));
-}
-
-void SetThisDeferredRunClass(Slot *s, Slot *sRun, int nval)
-{
- if (!sRun) return;
- for (Slot *p = sRun, *e = s->prev(); p != e; p = p->prev())
- if (p->getBidiClass() == WS) p->setBidiClass(nval | WSflag);
- else if (BaseClass(p) != BN) p->setBidiClass(nval | (p->getBidiClass() & WSflag));
-}
-
-void resolveWeak(Slot *start, int sos, int eos)
-{
- int state = (sos & 1) ? xr : xl;
- int cls;
- Slot *s = start;
- Slot *sRun = NULL;
- Slot *sLast = s;
-
- for ( ; s; s = s->prev())
- {
- sLast = s;
- cls = BaseClass(s);
- switch (cls)
- {
- case BN :
- if (s == start) start = s->prev(); // skip initial BNs for NSM resolving
- continue;
- case LRI :
- case RLI :
- case FSI :
- case PDI :
- {
- Slot *snext = s->prev();
- if (snext && snext->getBidiClass() == NSM)
- snext->setBidiClass(ON);
- s->setBidiClass(ON | WSflag);
- }
- break;
-
- case NSM :
- if (s == start)
- {
- cls = EmbeddingDirection(sos);
- s->setBidiClass(cls);
- }
- break;
- }
-
- bidi_action action = actionWeak[state][bidi_class_map[cls]];
- int clsRun = GetDeferredType(action);
- if (clsRun != XX)
- {
- SetDeferredRunClass(s, sRun, clsRun);
- sRun = NULL;
- }
- int clsNew = GetResolvedType(action);
- if (clsNew != XX)
- s->setBidiClass(clsNew);
- if (!sRun && (IX & action))
- sRun = s;
- state = stateWeak[state][bidi_class_map[cls]];
- }
-
- cls = EmbeddingDirection(eos);
- int clsRun = GetDeferredType(actionWeak[state][bidi_class_map[cls]]);
- if (clsRun != XX)
- SetThisDeferredRunClass(sLast, sRun, clsRun);
-}
-
-void processParens(Slot *s, Segment *seg, uint8 aMirror, int level, BracketPairStack &stack)
-{
- uint8 mask = 0;
- int8 lastDir = -1;
- BracketPair *p;
- for ( ; s; s = s->prev()) // walk the sequence
- {
- uint16 ogid = seg->glyphAttr(s->gid(), aMirror) || s->gid();
- int cls = BaseClass(s);
-
- switch(cls)
- {
- case OPP :
- stack.orin(mask);
- stack.push(ogid, s, lastDir, lastDir != CPP);
- mask = 0;
- lastDir = OPP;
- break;
- case CPP :
- stack.orin(mask);
- p = stack.scan(s->gid());
- if (!p) break;
- mask = 0;
- stack.close(p, s);
- lastDir = CPP;
- break;
- case L :
- lastDir = L;
- mask |= 1;
- break;
- case R :
- case AL :
- case AN :
- case EN :
- lastDir = R;
- mask |= 2;
- }
- }
- if (stack.size())
- {
- for (p = stack.start(); p; p =p->next()) // walk the stack
- {
- if (p->close() && p->mask())
- {
- int dir = (level & 1) + 1;
- if (p->mask() & dir)
- { }
- else if (p->mask() & (1 << (~level & 1))) // if inside has strong other embedding
- {
- int ldir = p->before();
- if ((p->before() == OPP || p->before() == CPP) && p->prev())
- {
- for (BracketPair *q = p->prev(); q; q = q->prev())
- {
- ldir = q->open()->getBidiClass();
- if (ldir < 3) break;
- ldir = q->before();
- if (ldir < 3) break;
- }
- if (ldir > 2) ldir = 0;
- }
- if (ldir > 0 && (ldir - 1) != (level & 1)) // is dir given opp. to level dir (ldir == R or L)
- dir = (~level & 1) + 1;
- }
- p->open()->setBidiClass(dir);
- p->close()->setBidiClass(dir);
- }
- }
- stack.clear();
- }
-}
-
-int GetDeferredNeutrals(int action, int level)
-{
- action = (action >> 4) & 0xF;
- if (action == (En >> 4))
- return EmbeddingDirection(level);
- else
- return action;
-}
-
-int GetResolvedNeutrals(int action)
-{
- return action & 0xF;
-}
-
-// 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
-} ;
-
-const uint8 neutral_class_map[] = { 0, 1, 2, 0, 4, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
-
-const int actionNeutrals[][5] =
-{
-// cls= N, L, R, AN, EN, 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
-} ;
-
-const int stateNeutrals[][5] =
-{
-// cls= N, L, R, AN, EN 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
-} ;
-
-void resolveNeutrals(Slot *s, int baseLevel, int sos, int eos)
-{
- int state = (sos & 1) ? r : l;
- int cls;
- Slot *sRun = NULL;
- Slot *sLast = s;
- int level = baseLevel;
-
- for ( ; s; s = s->prev())
- {
- sLast = s;
- cls = BaseClass(s);
- switch (cls)
- {
- case BN :
- continue;
- case LRI :
- case RLI :
- case FSI :
- s->setBidiClass(BN | WSflag);
- continue;
-
- default :
- int action = actionNeutrals[state][neutral_class_map[cls]];
- int clsRun = GetDeferredNeutrals(action, level);
- if (clsRun != N)
- {
- SetDeferredRunClass(s, sRun, clsRun);
- sRun = NULL;
- }
- int clsNew = GetResolvedNeutrals(action);
- if (clsNew != N)
- s->setBidiClass(clsNew);
- if (!sRun && (action & In))
- sRun = s;
- state = stateNeutrals[state][neutral_class_map[cls]];
- }
- }
- cls = EmbeddingDirection(eos);
- int clsRun = GetDeferredNeutrals(actionNeutrals[state][neutral_class_map[cls]], level);
- if (clsRun != N)
- SetThisDeferredRunClass(sLast, sRun, clsRun);
-}
-
-const int addLevel[][4] =
-{
- // cls = L, R, AN, EN level =
-/* even */ { 0, 1, 2, 2, }, // EVEN
-/* odd */ { 1, 0, 1, 1, }, // ODD
-
-};
-
-void resolveImplicit(Slot *s, Segment *seg, uint8 aMirror)
-{
- bool rtl = seg->dir() & 1;
- int level = rtl;
- Slot *slast = 0;
- for ( ; s; s = s->next())
- {
- int cls = BaseClass(s);
- s->prev(slast); // restitch the prev() side of the doubly linked list
- slast = s;
- if (cls == AN)
- cls = AL; // use AL value as the index for AN, no property change
- if (cls < 5 && cls > 0)
- {
- level = s->getBidiLevel();
- level += addLevel[level & 1][cls - 1];
- s->setBidiLevel(level);
- }
- if (aMirror)
- {
- int hasChar = seg->glyphAttr(s->gid(), aMirror + 1);
- if ( ((level & 1) && (!(seg->dir() & 4) || !hasChar))
- || ((rtl ^ (level & 1)) && (seg->dir() & 4) && hasChar) )
- {
- unsigned short g = seg->glyphAttr(s->gid(), aMirror);
- if (g) s->setGlyph(seg, g);
- }
- }
- }
-}
-
-void resolveWhitespace(int baseLevel, Slot *s)
-{
- for ( ; s; s = s->prev())
- {
- int8 cls = s->getBidiClass();
- if (cls == WS || (cls & WSflag))
- s->setBidiLevel(baseLevel);
- else if (cls != BN)
- break;
- }
-}
-
-
-/*
-Stitch two spans together to make another span (with ends tied together).
-If the level is odd then swap the order of the two spans
-*/
-inline
-Slot * join(int level, Slot * a, Slot * b)
-{
- if (!a) return b;
- if (level & 1) { Slot * const t = a; a = b; b = t; }
- Slot * const t = b->prev();
- a->prev()->next(b); b->prev(a->prev()); // splice middle
- t->next(a); a->prev(t); // splice ends
- return a;
-}
-
-/*
-Given the first slot in a run of slots with the same bidi level, turn the run
-into it's own little doubly linked list ring (a span) with the two ends joined together.
-If the run is rtl then reverse its direction.
-Returns the first slot after the span
-*/
-Slot * span(Slot * & cs, const bool rtl)
-{
- Slot * r = cs, * re = cs; cs = cs->next();
- if (rtl)
- {
- Slot * t = r->next(); r->next(r->prev()); r->prev(t);
- for (int l = r->getBidiLevel(); cs && (l == cs->getBidiLevel() || cs->getBidiClass() == BN); cs = cs->prev())
- {
- re = cs;
- t = cs->next(); cs->next(cs->prev()); cs->prev(t);
- }
- r->next(re);
- re->prev(r);
- r = re;
- }
- else
- {
- for (int l = r->getBidiLevel(); cs && (l == cs->getBidiLevel() || cs->getBidiClass() == BN); cs = cs->next())
- re = cs;
- r->prev(re);
- re->next(r);
- }
- if (cs) cs->prev(0);
- return r;
-}
-
-inline int getlevel(const Slot *cs, const int level)
-{
- while (cs && cs->getBidiClass() == BN)
- { cs = cs->next(); }
- if (cs)
- return cs->getBidiLevel();
- else
- return level;
-}
-
-Slot *resolveOrder(Slot * & cs, const bool reordered, const int level)
-{
- Slot * r = 0;
- int ls;
- while (cs && level <= (ls = getlevel(cs, level) - reordered))
- {
- r = join(level, r, level < ls
- ? resolveOrder(/* updates */cs, reordered, level+1) // find span of heighest level
- : span(/* updates */cs, level & 1));
- }
- return r;
-}