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resultiterator.cpp
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1
2 // File: resultiterator.cpp
3 // Description: Iterator for tesseract results that is capable of
4 // iterating in proper reading order over Bi Directional
5 // (e.g. mixed Hebrew and English) text.
6 // Author: David Eger
7 // Created: Fri May 27 13:58:06 PST 2011
8 //
9 // (C) Copyright 2011, Google Inc.
10 // Licensed under the Apache License, Version 2.0 (the "License");
11 // you may not use this file except in compliance with the License.
12 // You may obtain a copy of the License at
13 // http://www.apache.org/licenses/LICENSE-2.0
14 // Unless required by applicable law or agreed to in writing, software
15 // distributed under the License is distributed on an "AS IS" BASIS,
16 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 // See the License for the specific language governing permissions and
18 // limitations under the License.
19 //
21
22 #include "resultiterator.h"
23
24 #include "allheaders.h"
25 #include "pageres.h"
26 #include "strngs.h"
27 #include "tesseractclass.h"
28 #include "unicharset.h"
29 #include "unicodes.h"
30
31 namespace tesseract {
32
33 ResultIterator::ResultIterator(const LTRResultIterator &resit)
34 : LTRResultIterator(resit) {
35 in_minor_direction_ = false;
36 at_beginning_of_minor_run_ = false;
37 current_paragraph_is_ltr_ = CurrentParagraphIsLtr();
38 MoveToLogicalStartOfTextline();
39 }
40
41 ResultIterator *ResultIterator::StartOfParagraph(
42 const LTRResultIterator &resit) {
43 return new ResultIterator(resit);
44 }
45
46 bool ResultIterator::ParagraphIsLtr() const {
47 return current_paragraph_is_ltr_;
48 }
49
50 bool ResultIterator::CurrentParagraphIsLtr() const {
51 if (!it_->word())
52 return true; // doesn't matter.
53 LTRResultIterator it(*this);
54 it.RestartParagraph();
55 // Try to figure out the ltr-ness of the paragraph. The rules below
56 // make more sense in the context of a difficult paragraph example.
57 // Here we denote {ltr characters, RTL CHARACTERS}:
58 //
59 // "don't go in there!" DAIS EH
60 // EHT OTNI DEPMUJ FELSMIH NEHT DNA
61 // .GNIDLIUB GNINRUB
62 //
63 // On the first line, the left-most word is LTR and the rightmost word
64 // is RTL. Thus, we are better off taking the majority direction for
65 // the whole paragraph contents. So instead of "the leftmost word is LTR"
66 // indicating an LTR paragraph, we use a heuristic about what RTL paragraphs
67 // would not do: Typically an RTL paragraph would *not* start with an LTR
68 // word. So our heuristics are as follows:
69 //
70 // (1) If the first text line has an RTL word in the left-most position
71 // it is RTL.
72 // (2) If the first text line has an LTR word in the right-most position
73 // it is LTR.
74 // (3) If neither of the above is true, take the majority count for the
75 // paragraph -- if there are more rtl words, it is RTL. If there
76 // are more LTR words, it's LTR.
77 bool leftmost_rtl = it.WordDirection() == DIR_RIGHT_TO_LEFT;
78 bool rightmost_ltr = it.WordDirection() == DIR_LEFT_TO_RIGHT;
79 int num_ltr, num_rtl;
80 num_rtl = leftmost_rtl ? 1 : 0;
81 num_ltr = (it.WordDirection() == DIR_LEFT_TO_RIGHT) ? 1 : 0;
82 for (it.Next(RIL_WORD);
83 !it.Empty(RIL_WORD) && !it.IsAtBeginningOf(RIL_TEXTLINE);
84 it.Next(RIL_WORD)) {
85 StrongScriptDirection dir = it.WordDirection();
86 rightmost_ltr = (dir == DIR_LEFT_TO_RIGHT);
87 num_rtl += (dir == DIR_RIGHT_TO_LEFT) ? 1 : 0;
88 num_ltr += rightmost_ltr ? 1 : 0;
89 }
90 if (leftmost_rtl)
91 return false;
92 if (rightmost_ltr)
93 return true;
94 // First line is ambiguous. Take statistics on the whole paragraph.
95 if (!it.Empty(RIL_WORD) && !it.IsAtBeginningOf(RIL_PARA)) do {
96 StrongScriptDirection dir = it.WordDirection();
97 num_rtl += (dir == DIR_RIGHT_TO_LEFT) ? 1 : 0;
98 num_ltr += (dir == DIR_LEFT_TO_RIGHT) ? 1 : 0;
99 } while (it.Next(RIL_WORD) && !it.IsAtBeginningOf(RIL_PARA));
100 return num_ltr >= num_rtl;
101 }
102
103 const int ResultIterator::kMinorRunStart = -1;
104 const int ResultIterator::kMinorRunEnd = -2;
105 const int ResultIterator::kComplexWord = -3;
106
107 void ResultIterator::CalculateBlobOrder(
108 GenericVector<int> *blob_indices) const {
109 bool context_is_ltr = current_paragraph_is_ltr_ ^ in_minor_direction_;
110 blob_indices->clear();
111 if (Empty(RIL_WORD)) return;
112 if (context_is_ltr || it_->word()->UnicharsInReadingOrder()) {
113 // Easy! just return the blobs in order;
114 for (int i = 0; i < word_length_; i++)
115 blob_indices->push_back(i);
116 return;
117 }
118
119 // The blobs are in left-to-right order, but the current reading context
120 // is right-to-left.
121 const int U_LTR = UNICHARSET::U_LEFT_TO_RIGHT;
122 const int U_RTL = UNICHARSET::U_RIGHT_TO_LEFT;
123 const int U_EURO_NUM = UNICHARSET::U_EUROPEAN_NUMBER;
124 const int U_EURO_NUM_SEP = UNICHARSET::U_EUROPEAN_NUMBER_SEPARATOR;
125 const int U_EURO_NUM_TERM = UNICHARSET::U_EUROPEAN_NUMBER_TERMINATOR;
126 const int U_COMMON_NUM_SEP = UNICHARSET::U_COMMON_NUMBER_SEPARATOR;
127 const int U_OTHER_NEUTRAL = UNICHARSET::U_OTHER_NEUTRAL;
128
129 // Step 1: Scan for and mark European Number sequences
130 // [:ET:]*[:EN:]+(([:ES:]|[:CS:])?[:EN:]+)*[:ET:]*
131 GenericVector<int> letter_types;
132 for (int i = 0; i < word_length_; i++) {
133 letter_types.push_back(it_->word()->SymbolDirection(i));
134 }
135 // Convert a single separtor sandwiched between two EN's into an EN.
136 for (int i = 0; i + 2 < word_length_; i++) {
137 if (letter_types[i] == U_EURO_NUM && letter_types[i + 2] == U_EURO_NUM &&
138 (letter_types[i + 1] == U_EURO_NUM_SEP ||
139 letter_types[i + 1] == U_COMMON_NUM_SEP)) {
140 letter_types[i + 1] = U_EURO_NUM;
141 }
142 }
143 // Scan for sequences of European Number Terminators around ENs and convert
144 // them to ENs.
145 for (int i = 0; i < word_length_; i++) {
146 if (letter_types[i] == U_EURO_NUM_TERM) {
147 int j = i + 1;
148 while (j < word_length_ && letter_types[j] == U_EURO_NUM_TERM) { j++; }
149 if (j < word_length_ && letter_types[j] == U_EURO_NUM) {
150 // The sequence [i..j] should be converted to all European Numbers.
151 for (int k = i; k < j; k++) letter_types[k] = U_EURO_NUM;
152 }
153 j = i - 1;
154 while (j > -1 && letter_types[j] == U_EURO_NUM_TERM) { j--; }
155 if (j > -1 && letter_types[j] == U_EURO_NUM) {
156 // The sequence [j..i] should be converted to all European Numbers.
157 for (int k = j; k <= i; k++) letter_types[k] = U_EURO_NUM;
158 }
159 }
160 }
161 // Step 2: Convert all remaining types to either L or R.
162 // Sequences ([:L:]|[:EN:])+ (([:CS:]|[:ON:])+ ([:L:]|[:EN:])+)* -> L.
163 // All other are R.
164 for (int i = 0; i < word_length_;) {
165 int ti = letter_types[i];
166 if (ti == U_LTR || ti == U_EURO_NUM) {
167 // Left to right sequence; scan to the end of it.
168 int last_good = i;
169 for (int j = i + 1; j < word_length_; j++) {
170 int tj = letter_types[j];
171 if (tj == U_LTR || tj == U_EURO_NUM) {
172 last_good = j;
173 } else if (tj == U_COMMON_NUM_SEP || tj == U_OTHER_NEUTRAL) {
174 // do nothing.
175 } else {
176 break;
177 }
178 }
179 // [i..last_good] is the L sequence
180 for (int k = i; k <= last_good; k++) letter_types[k] = U_LTR;
181 i = last_good + 1;
182 } else {
183 letter_types[i] = U_RTL;
184 i++;
185 }
186 }
187
188 // At this point, letter_types is entirely U_LTR or U_RTL.
189 for (int i = word_length_ - 1; i >= 0;) {
190 if (letter_types[i] == U_RTL) {
191 blob_indices->push_back(i);
192 i--;
193 } else {
194 // left to right sequence. scan to the beginning.
195 int j = i - 1;
196 for (; j >= 0 && letter_types[j] != U_RTL; j--) { } // pass
197 // Now (j, i] is LTR
198 for (int k = j + 1; k <= i; k++) blob_indices->push_back(k);
199 i = j;
200 }
201 }
202 ASSERT_HOST(blob_indices->size() == word_length_);
203 }
204
205 static void PrintScriptDirs(const GenericVector<StrongScriptDirection> &dirs) {
206 for (int i = 0; i < dirs.size(); i++) {
207 switch (dirs[i]) {
208 case DIR_NEUTRAL: tprintf ("N "); break;
209 case DIR_LEFT_TO_RIGHT: tprintf("L "); break;
210 case DIR_RIGHT_TO_LEFT: tprintf("R "); break;
211 case DIR_MIX: tprintf("Z "); break;
212 default: tprintf("? "); break;
213 }
214 }
215 tprintf("\n");
216 }
217
218 void ResultIterator::CalculateTextlineOrder(
219 bool paragraph_is_ltr,
220 const LTRResultIterator &resit,
221 GenericVectorEqEq<int> *word_indices) const {
222 GenericVector<StrongScriptDirection> directions;
223 CalculateTextlineOrder(paragraph_is_ltr, resit, &directions, word_indices);
224 }
225
226 void ResultIterator::CalculateTextlineOrder(
227 bool paragraph_is_ltr,
228 const LTRResultIterator &resit,
229 GenericVector<StrongScriptDirection> *dirs_arg,
230 GenericVectorEqEq<int> *word_indices) const {
231 GenericVector<StrongScriptDirection> dirs;
232 GenericVector<StrongScriptDirection> *directions;
233 directions = (dirs_arg != NULL) ? dirs_arg : &dirs;
234 directions->truncate(0);
235
236 // A LTRResultIterator goes strictly left-to-right word order.
237 LTRResultIterator ltr_it(resit);
238 ltr_it.RestartRow();
239 if (ltr_it.Empty(RIL_WORD)) return;
240 do {
241 directions->push_back(ltr_it.WordDirection());
242 } while (ltr_it.Next(RIL_WORD) && !ltr_it.IsAtBeginningOf(RIL_TEXTLINE));
243
244 word_indices->truncate(0);
245 CalculateTextlineOrder(paragraph_is_ltr, *directions, word_indices);
246 }
247
248 void ResultIterator::CalculateTextlineOrder(
249 bool paragraph_is_ltr,
250 const GenericVector<StrongScriptDirection> &word_dirs,
251 GenericVectorEqEq<int> *reading_order) {
252 reading_order->truncate(0);
253 if (word_dirs.size() == 0) return;
254
255 // Take all of the runs of minor direction words and insert them
256 // in reverse order.
257 int minor_direction, major_direction, major_step, start, end;
258 if (paragraph_is_ltr) {
259 start = 0;
260 end = word_dirs.size();
261 major_step = 1;
262 major_direction = DIR_LEFT_TO_RIGHT;
263 minor_direction = DIR_RIGHT_TO_LEFT;
264 } else {
265 start = word_dirs.size() - 1;
266 end = -1;
267 major_step = -1;
268 major_direction = DIR_RIGHT_TO_LEFT;
269 minor_direction = DIR_LEFT_TO_RIGHT;
270 // Special rule: if there are neutral words at the right most side
271 // of a line adjacent to a left-to-right word in the middle of the
272 // line, we interpret the end of the line as a single LTR sequence.
273 if (word_dirs[start] == DIR_NEUTRAL) {
274 int neutral_end = start;
275 while (neutral_end > 0 && word_dirs[neutral_end] == DIR_NEUTRAL) {
276 neutral_end--;
277 }
278 if (neutral_end >= 0 && word_dirs[neutral_end] == DIR_LEFT_TO_RIGHT) {
279 // LTR followed by neutrals.
280 // Scan for the beginning of the minor left-to-right run.
281 int left = neutral_end;
282 for (int i = left; i >= 0 && word_dirs[i] != DIR_RIGHT_TO_LEFT; i--) {
283 if (word_dirs[i] == DIR_LEFT_TO_RIGHT) left = i;
284 }
285 reading_order->push_back(kMinorRunStart);
286 for (int i = left; i < word_dirs.size(); i++) {
287 reading_order->push_back(i);
288 if (word_dirs[i] == DIR_MIX) reading_order->push_back(kComplexWord);
289 }
290 reading_order->push_back(kMinorRunEnd);
291 start = left - 1;
292 }
293 }
294 }
295 for (int i = start; i != end;) {
296 if (word_dirs[i] == minor_direction) {
297 int j = i;
298 while (j != end && word_dirs[j] != major_direction)
299 j += major_step;
300 if (j == end) j -= major_step;
301 while (j != i && word_dirs[j] != minor_direction)
302 j -= major_step;
303 // [j..i] is a minor direction run.
304 reading_order->push_back(kMinorRunStart);
305 for (int k = j; k != i; k -= major_step) {
306 reading_order->push_back(k);
307 }
308 reading_order->push_back(i);
309 reading_order->push_back(kMinorRunEnd);
310 i = j + major_step;
311 } else {
312 reading_order->push_back(i);
313 if (word_dirs[i] == DIR_MIX) reading_order->push_back(kComplexWord);
314 i += major_step;
315 }
316 }
317 }
318
319 int ResultIterator::LTRWordIndex() const {
320 int this_word_index = 0;
321 LTRResultIterator textline(*this);
322 textline.RestartRow();
323 while (!textline.PositionedAtSameWord(it_)) {
324 this_word_index++;
325 textline.Next(RIL_WORD);
326 }
327 return this_word_index;
328 }
329
330 void ResultIterator::MoveToLogicalStartOfWord() {
331 if (word_length_ == 0) {
332 BeginWord(0);
333 return;
334 }
335 GenericVector<int> blob_order;
336 CalculateBlobOrder(&blob_order);
337 if (blob_order.size() == 0 || blob_order[0] == 0) return;
338 BeginWord(blob_order[0]);
339 }
340
341 bool ResultIterator::IsAtFinalSymbolOfWord() const {
342 if (!it_->word()) return true;
343 GenericVector<int> blob_order;
344 CalculateBlobOrder(&blob_order);
345 return blob_order.size() == 0 || blob_order.back() == blob_index_;
346 }
347
348 bool ResultIterator::IsAtFirstSymbolOfWord() const {
349 if (!it_->word()) return true;
350 GenericVector<int> blob_order;
351 CalculateBlobOrder(&blob_order);
352 return blob_order.size() == 0 || blob_order[0] == blob_index_;
353 }
354
355 void ResultIterator::AppendSuffixMarks(STRING *text) const {
356 if (!it_->word()) return;
357 bool reading_direction_is_ltr =
358 current_paragraph_is_ltr_ ^ in_minor_direction_;
359 // scan forward to see what meta-information the word ordering algorithm
360 // left us.
361 // If this word is at the *end* of a minor run, insert the other
362 // direction's mark; else if this was a complex word, insert the
363 // current reading order's mark.
364 GenericVectorEqEq<int> textline_order;
365 CalculateTextlineOrder(current_paragraph_is_ltr_,
366 *this, &textline_order);
367 int this_word_index = LTRWordIndex();
368 int i = textline_order.get_index(this_word_index);
369 if (i < 0) return;
370
371 int last_non_word_mark = 0;
372 for (i++; i < textline_order.size() && textline_order[i] < 0; i++) {
373 last_non_word_mark = textline_order[i];
374 }
375 if (last_non_word_mark == kComplexWord) {
376 *text += reading_direction_is_ltr ? kLRM : kRLM;
377 } else if (last_non_word_mark == kMinorRunEnd) {
378 if (current_paragraph_is_ltr_) {
379 *text += kRLM;
380 *text += kLRM;
381 } else {
382 *text += kRLM;
383 *text += kLRM;
384 }
385 }
386 }
387
388 void ResultIterator::MoveToLogicalStartOfTextline() {
389 GenericVectorEqEq<int> word_indices;
390 RestartRow();
391 CalculateTextlineOrder(current_paragraph_is_ltr_,
392 dynamic_cast<const LTRResultIterator&>(*this),
393 &word_indices);
394 int i = 0;
395 for (; i < word_indices.size() && word_indices[i] < 0; i++) {
396 if (word_indices[i] == kMinorRunStart) in_minor_direction_ = true;
397 else if (word_indices[i] == kMinorRunEnd) in_minor_direction_ = false;
398 }
399 if (in_minor_direction_) at_beginning_of_minor_run_ = true;
400 if (i >= word_indices.size()) return;
401 int first_word_index = word_indices[i];
402 for (int j = 0; j < first_word_index; j++) {
403 PageIterator::Next(RIL_WORD);
404 }
405 MoveToLogicalStartOfWord();
406 }
407
408 void ResultIterator::Begin() {
409 LTRResultIterator::Begin();
410 current_paragraph_is_ltr_ = CurrentParagraphIsLtr();
411 in_minor_direction_ = false;
412 at_beginning_of_minor_run_ = false;
413 MoveToLogicalStartOfTextline();
414 }
415
416 bool ResultIterator::Next(PageIteratorLevel level) {
417 if (it_->block() == NULL) return false; // already at end!
418 switch (level) {
419 case RIL_BLOCK: // explicit fall-through
420 case RIL_PARA: // explicit fall-through
421 case RIL_TEXTLINE:
422 if (!PageIterator::Next(level)) return false;
423 if (IsWithinFirstTextlineOfParagraph()) {
424 // if we've advanced to a new paragraph,
425 // recalculate current_paragraph_is_ltr_
426 current_paragraph_is_ltr_ = CurrentParagraphIsLtr();
427 }
428 in_minor_direction_ = false;
429 MoveToLogicalStartOfTextline();
430 return it_->block() != NULL;
431 case RIL_SYMBOL:
432 {
433 GenericVector<int> blob_order;
434 CalculateBlobOrder(&blob_order);
435 int next_blob = 0;
436 while (next_blob < blob_order.size() &&
437 blob_index_ != blob_order[next_blob])
438 next_blob++;
439 next_blob++;
440 if (next_blob < blob_order.size()) {
441 // we're in the same word; simply advance one blob.
442 BeginWord(blob_order[next_blob]);
443 at_beginning_of_minor_run_ = false;
444 return true;
445 }
446 level = RIL_WORD; // we've fallen through to the next word.
447 }
448 case RIL_WORD: // explicit fall-through.
449 {
450 if (it_->word() == NULL) return Next(RIL_BLOCK);
451 GenericVectorEqEq<int> word_indices;
452 int this_word_index = LTRWordIndex();
453 CalculateTextlineOrder(current_paragraph_is_ltr_,
454 *this,
455 &word_indices);
456 int final_real_index = word_indices.size() - 1;
457 while (final_real_index > 0 && word_indices[final_real_index] < 0)
458 final_real_index--;
459 for (int i = 0; i < final_real_index; i++) {
460 if (word_indices[i] == this_word_index) {
461 int j = i + 1;
462 for (; j < final_real_index && word_indices[j] < 0; j++) {
463 if (word_indices[j] == kMinorRunStart) in_minor_direction_ = true;
464 if (word_indices[j] == kMinorRunEnd) in_minor_direction_ = false;
465 }
466 at_beginning_of_minor_run_ = (word_indices[j - 1] == kMinorRunStart);
467 // awesome, we move to word_indices[j]
468 if (BidiDebug(3)) {
469 tprintf("Next(RIL_WORD): %d -> %d\n",
470 this_word_index, word_indices[j]);
471 }
472 PageIterator::RestartRow();
473 for (int k = 0; k < word_indices[j]; k++) {
474 PageIterator::Next(RIL_WORD);
475 }
476 MoveToLogicalStartOfWord();
477 return true;
478 }
479 }
480 if (BidiDebug(3)) {
481 tprintf("Next(RIL_WORD): %d -> EOL\n", this_word_index);
482 }
483 // we're going off the end of the text line.
484 return Next(RIL_TEXTLINE);
485 }
486 }
487 ASSERT_HOST(false); // shouldn't happen.
488 return false;
489 }
490
491 bool ResultIterator::IsAtBeginningOf(PageIteratorLevel level) const {
492 if (it_->block() == NULL) return false; // Already at the end!
493 if (it_->word() == NULL) return true; // In an image block.
494 if (level == RIL_SYMBOL) return true; // Always at beginning of a symbol.
495
496 bool at_word_start = IsAtFirstSymbolOfWord();
497 if (level == RIL_WORD) return at_word_start;
498
499 ResultIterator line_start(*this);
500 // move to the first word in the line...
501 line_start.MoveToLogicalStartOfTextline();
502
503 bool at_textline_start = at_word_start && *line_start.it_ == *it_;
504 if (level == RIL_TEXTLINE) return at_textline_start;
505
506 // now we move to the left-most word...
507 line_start.RestartRow();
508 bool at_block_start = at_textline_start &&
509 line_start.it_->block() != line_start.it_->prev_block();
510 if (level == RIL_BLOCK) return at_block_start;
511
512 bool at_para_start = at_block_start ||
513 (at_textline_start &&
514 line_start.it_->row()->row->para() !=
515 line_start.it_->prev_row()->row->para());
516 if (level == RIL_PARA) return at_para_start;
517
518 ASSERT_HOST(false); // shouldn't happen.
519 return false;
520 }
521
527 bool ResultIterator::IsAtFinalElement(PageIteratorLevel level,
528 PageIteratorLevel element) const {
529 if (Empty(element)) return true; // Already at the end!
530 // The result is true if we step forward by element and find we are
531 // at the the end of the page or at beginning of *all* levels in:
532 // [level, element).
533 // When there is more than one level difference between element and level,
534 // we could for instance move forward one symbol and still be at the first
535 // word on a line, so we also have to be at the first symbol in a word.
536 ResultIterator next(*this);
537 next.Next(element);
538 if (next.Empty(element)) return true; // Reached the end of the page.
539 while (element > level) {
540 element = static_cast<PageIteratorLevel>(element - 1);
541 if (!next.IsAtBeginningOf(element))
542 return false;
543 }
544 return true;
545 }
546
551 char* ResultIterator::GetUTF8Text(PageIteratorLevel level) const {
552 if (it_->word() == NULL) return NULL; // Already at the end!
553 STRING text;
554 switch (level) {
555 case RIL_BLOCK:
556 {
557 ResultIterator pp(*this);
558 do {
559 pp.AppendUTF8ParagraphText(&text);
560 } while (pp.Next(RIL_PARA) && pp.it_->block() == it_->block());
561 }
562 break;
563 case RIL_PARA:
564 AppendUTF8ParagraphText(&text);
565 break;
566 case RIL_TEXTLINE:
567 {
568 ResultIterator it(*this);
569 it.MoveToLogicalStartOfTextline();
570 it.IterateAndAppendUTF8TextlineText(&text);
571 }
572 break;
573 case RIL_WORD:
574 AppendUTF8WordText(&text);
575 break;
576 case RIL_SYMBOL:
577 {
578 bool reading_direction_is_ltr =
579 current_paragraph_is_ltr_ ^ in_minor_direction_;
580 if (at_beginning_of_minor_run_) {
581 text += reading_direction_is_ltr ? kLRM : kRLM;
582 }
583 text = it_->word()->BestUTF8(blob_index_, !reading_direction_is_ltr);
584 if (IsAtFinalSymbolOfWord()) AppendSuffixMarks(&text);
585 }
586 break;
587 }
588 int length = text.length() + 1;
589 char* result = new char[length];
590 strncpy(result, text.string(), length);
591 return result;
592 }
593
594 void ResultIterator::AppendUTF8WordText(STRING *text) const {
595 if (!it_->word()) return;
596 ASSERT_HOST(it_->word()->best_choice != NULL);
597 bool reading_direction_is_ltr =
598 current_paragraph_is_ltr_ ^ in_minor_direction_;
599 if (at_beginning_of_minor_run_) {
600 *text += reading_direction_is_ltr ? kLRM : kRLM;
601 }
602
603 GenericVector<int> blob_order;
604 CalculateBlobOrder(&blob_order);
605 for (int i = 0; i < blob_order.size(); i++) {
606 *text += it_->word()->BestUTF8(blob_order[i], !reading_direction_is_ltr);
607 }
608 AppendSuffixMarks(text);
609 }
610
611 void ResultIterator::IterateAndAppendUTF8TextlineText(STRING *text) {
612 if (Empty(RIL_WORD)) {
613 Next(RIL_WORD);
614 return;
615 }
616 if (BidiDebug(1)) {
617 GenericVectorEqEq<int> textline_order;
618 GenericVector<StrongScriptDirection> dirs;
619 CalculateTextlineOrder(current_paragraph_is_ltr_,
620 *this, &dirs, &textline_order);
621 tprintf("Strong Script dirs [%p/P=%s]: ", it_->row(),
622 current_paragraph_is_ltr_ ? "ltr" : "rtl");
623 PrintScriptDirs(dirs);
624 tprintf("Logical textline order [%p/P=%s]: ", it_->row(),
625 current_paragraph_is_ltr_ ? "ltr" : "rtl");
626 for (int i = 0; i < textline_order.size(); i++) {
627 tprintf("%d ", textline_order[i]);
628 }
629 tprintf("\n");
630 }
631
632 int words_appended = 0;
633 do {
634 AppendUTF8WordText(text);
635 words_appended++;
636 *text += " ";
637 } while (Next(RIL_WORD) && !IsAtBeginningOf(RIL_TEXTLINE));
638 if (BidiDebug(1)) {
639 tprintf("%d words printed\n", words_appended);
640 }
641 text->truncate_at(text->length() - 1);
642 *text += line_separator_;
643 // If we just finished a paragraph, add an extra newline.
644 if (it_->block() == NULL || IsAtBeginningOf(RIL_PARA))
645 *text += paragraph_separator_;
646 }
647
648 void ResultIterator::AppendUTF8ParagraphText(STRING *text) const {
649 ResultIterator it(*this);
650 it.RestartParagraph();
651 it.MoveToLogicalStartOfTextline();
652 if (it.Empty(RIL_WORD)) return;
653 do {
654 it.IterateAndAppendUTF8TextlineText(text);
655 } while (it.it_->block() != NULL && !it.IsAtBeginningOf(RIL_PARA));
656 }
657
658 bool ResultIterator::BidiDebug(int min_level) const {
659 int debug_level = 1;
660 IntParam *p = ParamUtils::FindParam<IntParam>(
661 "bidi_debug", GlobalParams()->int_params,
662 tesseract_->params()->int_params);
663 if (p != NULL) debug_level = (inT32)(*p);
664 return debug_level >= min_level;
665 }
666
667 } // namespace tesseract.