DALi Version 2.1.17
[platform/core/uifw/dali-toolkit.git] / dali-toolkit / internal / text / text-controller-relayouter.cpp
1 /*
2  * Copyright (c) 2022 Samsung Electronics Co., Ltd.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  *
16  */
17
18 // CLASS HEADER
19 #include <dali-toolkit/internal/text/text-controller-relayouter.h>
20
21 // EXTERNAL INCLUDES
22 #include <dali/integration-api/debug.h>
23 #include <limits>
24
25 // INTERNAL INCLUDES
26 #include <dali-toolkit/internal/text/layouts/layout-parameters.h>
27 #include <dali-toolkit/internal/text/text-controller-event-handler.h>
28 #include <dali-toolkit/internal/text/text-controller-impl.h>
29
30 namespace
31 {
32 #if defined(DEBUG_ENABLED)
33 Debug::Filter* gLogFilter = Debug::Filter::New(Debug::NoLogging, true, "LOG_TEXT_CONTROLS");
34 #endif
35
36 constexpr float MAX_FLOAT = std::numeric_limits<float>::max();
37
38 float ConvertToEven(float value)
39 {
40   int intValue(static_cast<int>(value));
41   return static_cast<float>(intValue + (intValue & 1));
42 }
43
44 } // namespace
45
46 namespace Dali
47 {
48 namespace Toolkit
49 {
50 namespace Text
51 {
52 Size Controller::Relayouter::CalculateLayoutSizeOnRequiredControllerSize(Controller& controller, const Size& requestedControllerSize, const OperationsMask& requestedOperationsMask)
53 {
54   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->CalculateLayoutSizeOnRequiredControllerSize\n");
55   Size calculatedLayoutSize;
56
57   Controller::Impl& impl        = *controller.mImpl;
58   ModelPtr&         model       = impl.mModel;
59   VisualModelPtr&   visualModel = model->mVisualModel;
60
61   // Operations that can be done only once until the text changes.
62   const OperationsMask onlyOnceOperations = static_cast<OperationsMask>(CONVERT_TO_UTF32 |
63                                                                         GET_SCRIPTS |
64                                                                         VALIDATE_FONTS |
65                                                                         GET_LINE_BREAKS |
66                                                                         BIDI_INFO |
67                                                                         SHAPE_TEXT |
68                                                                         GET_GLYPH_METRICS);
69
70   // Set the update info to relayout the whole text.
71   TextUpdateInfo& textUpdateInfo = impl.mTextUpdateInfo;
72   if((0 == textUpdateInfo.mNumberOfCharactersToAdd) &&
73      (0 == textUpdateInfo.mPreviousNumberOfCharacters) &&
74      ((visualModel->mControlSize.width < Math::MACHINE_EPSILON_1000) || (visualModel->mControlSize.height < Math::MACHINE_EPSILON_1000)))
75   {
76     textUpdateInfo.mNumberOfCharactersToAdd = model->mLogicalModel->mText.Count();
77   }
78   textUpdateInfo.mParagraphCharacterIndex     = 0u;
79   textUpdateInfo.mRequestedNumberOfCharacters = model->mLogicalModel->mText.Count();
80
81   // This is to keep Index to the first character to be updated.
82   // Then restore it after calling Clear method.
83   auto updateInfoCharIndexBackup = textUpdateInfo.mCharacterIndex;
84
85   // Get a reference to the pending operations member
86   OperationsMask& operationsPending = impl.mOperationsPending;
87
88   // Layout the text for the new width.
89   // Apply the pending operations, requested operations and the only once operations.
90   // Then remove onlyOnceOperations
91   operationsPending = static_cast<OperationsMask>(operationsPending | requestedOperationsMask | onlyOnceOperations);
92
93   // Make sure the model is up-to-date before layouting
94   impl.UpdateModel(static_cast<OperationsMask>(operationsPending & ~UPDATE_LAYOUT_SIZE));
95
96   // Store the actual control's size to restore later.
97   const Size actualControlSize = visualModel->mControlSize;
98
99   DoRelayout(impl,
100              requestedControllerSize,
101              static_cast<OperationsMask>(operationsPending & ~UPDATE_LAYOUT_SIZE),
102              calculatedLayoutSize);
103
104   // Clear the update info. This info will be set the next time the text is updated.
105   textUpdateInfo.Clear();
106
107   //TODO: Refactor "DoRelayout" and extract common code of size calculation without modifying attributes of mVisualModel,
108   //TODO: then calculate GlyphPositions. Lines, Size, Layout for Natural-Size
109   //TODO: and utilize the values in OperationsPending and TextUpdateInfo without changing the original one.
110   //TODO: Also it will improve performance because there is no need todo FullRelyout on the next need for layouting.
111
112   // FullRelayoutNeeded should be true because DoRelayout is MAX_FLOAT, MAX_FLOAT.
113   // By this no need to take backup and restore it.
114   textUpdateInfo.mFullRelayoutNeeded = true;
115
116   // Restore mCharacterIndex. Because "Clear" set it to the maximum integer.
117   // The "CalculateTextUpdateIndices" does not work proprely because the mCharacterIndex will be greater than mPreviousNumberOfCharacters.
118   // Which apply an assumption to update only the last  paragraph. That could cause many of out of index crashes.
119   textUpdateInfo.mCharacterIndex = updateInfoCharIndexBackup;
120
121   // Do not do again the only once operations.
122   operationsPending = static_cast<OperationsMask>(operationsPending & ~onlyOnceOperations);
123
124   // Do the size related operations again.
125
126   const OperationsMask sizeOperations = static_cast<OperationsMask>(LAYOUT |
127                                                                     ALIGN |
128                                                                     REORDER);
129
130   operationsPending = static_cast<OperationsMask>(operationsPending | sizeOperations);
131
132   // Restore the actual control's size.
133   visualModel->mControlSize = actualControlSize;
134
135   return calculatedLayoutSize;
136 }
137
138 Vector3 Controller::Relayouter::GetNaturalSize(Controller& controller)
139 {
140   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->Controller::GetNaturalSize\n");
141   Vector3 naturalSizeVec3;
142
143   // Make sure the model is up-to-date before layouting
144   EventHandler::ProcessModifyEvents(controller);
145
146   Controller::Impl& impl        = *controller.mImpl;
147   ModelPtr&         model       = impl.mModel;
148   VisualModelPtr&   visualModel = model->mVisualModel;
149
150   if(impl.mRecalculateNaturalSize)
151   {
152     Size naturalSize;
153
154     // Layout the text for the new width.
155     OperationsMask requestedOperationsMask  = static_cast<OperationsMask>(LAYOUT | REORDER);
156     Size           sizeMaxWidthAndMaxHeight = Size(MAX_FLOAT, MAX_FLOAT);
157
158     naturalSize = CalculateLayoutSizeOnRequiredControllerSize(controller, sizeMaxWidthAndMaxHeight, requestedOperationsMask);
159
160     // Stores the natural size to avoid recalculate it again
161     // unless the text/style changes.
162     visualModel->SetNaturalSize(naturalSize);
163     naturalSizeVec3 = naturalSize;
164
165     impl.mRecalculateNaturalSize = false;
166
167     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::GetNaturalSize calculated %f,%f,%f\n", naturalSizeVec3.x, naturalSizeVec3.y, naturalSizeVec3.z);
168   }
169   else
170   {
171     naturalSizeVec3 = visualModel->GetNaturalSize();
172
173     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::GetNaturalSize cached %f,%f,%f\n", naturalSizeVec3.x, naturalSizeVec3.y, naturalSizeVec3.z);
174   }
175
176   naturalSizeVec3.x = ConvertToEven(naturalSizeVec3.x);
177   naturalSizeVec3.y = ConvertToEven(naturalSizeVec3.y);
178
179   return naturalSizeVec3;
180 }
181
182 bool Controller::Relayouter::CheckForTextFit(Controller& controller, float pointSize, const Size& layoutSize)
183 {
184   Size              textSize;
185   Controller::Impl& impl            = *controller.mImpl;
186   TextUpdateInfo&   textUpdateInfo  = impl.mTextUpdateInfo;
187   impl.mFontDefaults->mFitPointSize = pointSize;
188   impl.mFontDefaults->sizeDefined   = true;
189   impl.ClearFontData();
190
191   // Operations that can be done only once until the text changes.
192   const OperationsMask onlyOnceOperations = static_cast<OperationsMask>(CONVERT_TO_UTF32 |
193                                                                         GET_SCRIPTS |
194                                                                         VALIDATE_FONTS |
195                                                                         GET_LINE_BREAKS |
196                                                                         BIDI_INFO |
197                                                                         SHAPE_TEXT |
198                                                                         GET_GLYPH_METRICS);
199
200   textUpdateInfo.mParagraphCharacterIndex     = 0u;
201   textUpdateInfo.mRequestedNumberOfCharacters = impl.mModel->mLogicalModel->mText.Count();
202
203   // Make sure the model is up-to-date before layouting
204   impl.UpdateModel(onlyOnceOperations);
205
206   DoRelayout(impl,
207              Size(layoutSize.width, MAX_FLOAT),
208              static_cast<OperationsMask>(onlyOnceOperations | LAYOUT),
209              textSize);
210
211   // Clear the update info. This info will be set the next time the text is updated.
212   textUpdateInfo.Clear();
213   textUpdateInfo.mClearAll = true;
214
215   if(textSize.width > layoutSize.width || textSize.height > layoutSize.height)
216   {
217     return false;
218   }
219   return true;
220 }
221
222 void Controller::Relayouter::FitPointSizeforLayout(Controller& controller, const Size& layoutSize)
223 {
224   Controller::Impl& impl = *controller.mImpl;
225
226   const OperationsMask operations = impl.mOperationsPending;
227   if(NO_OPERATION != (UPDATE_LAYOUT_SIZE & operations) || impl.mTextFitContentSize != layoutSize)
228   {
229     ModelPtr& model = impl.mModel;
230
231     bool  actualellipsis      = model->mElideEnabled;
232     float minPointSize        = impl.mTextFitMinSize;
233     float maxPointSize        = impl.mTextFitMaxSize;
234     float pointInterval       = impl.mTextFitStepSize;
235     float currentFitPointSize = impl.mFontDefaults->mFitPointSize;
236
237     model->mElideEnabled = false;
238     Vector<float> pointSizeArray;
239
240     // check zero value
241     if(pointInterval < 1.f)
242     {
243       impl.mTextFitStepSize = pointInterval = 1.0f;
244     }
245
246     pointSizeArray.Reserve(static_cast<unsigned int>(ceil((maxPointSize - minPointSize) / pointInterval)));
247
248     for(float i = minPointSize; i < maxPointSize; i += pointInterval)
249     {
250       pointSizeArray.PushBack(i);
251     }
252
253     pointSizeArray.PushBack(maxPointSize);
254
255     int bestSizeIndex = 0;
256     int min           = bestSizeIndex + 1;
257     int max           = pointSizeArray.Size() - 1;
258     while(min <= max)
259     {
260       int destI = (min + max) / 2;
261
262       if(CheckForTextFit(controller, pointSizeArray[destI], layoutSize))
263       {
264         bestSizeIndex = min;
265         min           = destI + 1;
266       }
267       else
268       {
269         max           = destI - 1;
270         bestSizeIndex = max;
271       }
272     }
273
274     model->mElideEnabled = actualellipsis;
275     if(currentFitPointSize != pointSizeArray[bestSizeIndex])
276     {
277       impl.mTextFitChanged = true;
278     }
279     impl.mFontDefaults->mFitPointSize = pointSizeArray[bestSizeIndex];
280     impl.mFontDefaults->sizeDefined   = true;
281     impl.ClearFontData();
282   }
283 }
284
285 float Controller::Relayouter::GetHeightForWidth(Controller& controller, float width)
286 {
287   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->Controller::GetHeightForWidth %p width %f\n", &controller, width);
288
289   // Make sure the model is up-to-date before layouting
290   EventHandler::ProcessModifyEvents(controller);
291
292   Controller::Impl& impl           = *controller.mImpl;
293   ModelPtr&         model          = impl.mModel;
294   VisualModelPtr&   visualModel    = model->mVisualModel;
295   TextUpdateInfo&   textUpdateInfo = impl.mTextUpdateInfo;
296
297   Size layoutSize;
298
299   if(fabsf(width - visualModel->mControlSize.width) > Math::MACHINE_EPSILON_1000 ||
300      textUpdateInfo.mFullRelayoutNeeded ||
301      textUpdateInfo.mClearAll)
302   {
303     // Layout the text for the new width.
304     OperationsMask requestedOperationsMask        = static_cast<OperationsMask>(LAYOUT);
305     Size           sizeRequestedWidthAndMaxHeight = Size(width, MAX_FLOAT);
306
307     layoutSize = CalculateLayoutSizeOnRequiredControllerSize(controller, sizeRequestedWidthAndMaxHeight, requestedOperationsMask);
308
309     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::GetHeightForWidth calculated %f\n", layoutSize.height);
310   }
311   else
312   {
313     layoutSize = visualModel->GetLayoutSize();
314     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::GetHeightForWidth cached %f\n", layoutSize.height);
315   }
316
317   return layoutSize.height;
318 }
319
320 Controller::UpdateTextType Controller::Relayouter::Relayout(Controller& controller, const Size& size, Dali::LayoutDirection::Type layoutDirection)
321 {
322   Controller::Impl& impl           = *controller.mImpl;
323   ModelPtr&         model          = impl.mModel;
324   VisualModelPtr&   visualModel    = model->mVisualModel;
325   TextUpdateInfo&   textUpdateInfo = impl.mTextUpdateInfo;
326
327   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->Controller::Relayout %p size %f,%f, autoScroll[%s]\n", &controller, size.width, size.height, impl.mIsAutoScrollEnabled ? "true" : "false");
328
329   UpdateTextType updateTextType = NONE_UPDATED;
330
331   if((size.width < Math::MACHINE_EPSILON_1000) || (size.height < Math::MACHINE_EPSILON_1000))
332   {
333     if(0u != visualModel->mGlyphPositions.Count())
334     {
335       visualModel->mGlyphPositions.Clear();
336       updateTextType = MODEL_UPDATED;
337     }
338
339     // Clear the update info. This info will be set the next time the text is updated.
340     textUpdateInfo.Clear();
341
342     // Not worth to relayout if width or height is equal to zero.
343     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::Relayout (skipped)\n");
344
345     return updateTextType;
346   }
347
348   // Whether a new size has been set.
349   const bool newSize = (size != visualModel->mControlSize);
350
351   // Get a reference to the pending operations member
352   OperationsMask& operationsPending = impl.mOperationsPending;
353
354   if(newSize)
355   {
356     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "new size (previous size %f,%f)\n", visualModel->mControlSize.width, visualModel->mControlSize.height);
357
358     if((0 == textUpdateInfo.mNumberOfCharactersToAdd) &&
359        (0 == textUpdateInfo.mPreviousNumberOfCharacters) &&
360        ((visualModel->mControlSize.width < Math::MACHINE_EPSILON_1000) || (visualModel->mControlSize.height < Math::MACHINE_EPSILON_1000)))
361     {
362       textUpdateInfo.mNumberOfCharactersToAdd = model->mLogicalModel->mText.Count();
363     }
364
365     // Layout operations that need to be done if the size changes.
366     operationsPending = static_cast<OperationsMask>(operationsPending |
367                                                     LAYOUT |
368                                                     ALIGN |
369                                                     UPDATE_LAYOUT_SIZE |
370                                                     REORDER);
371     // Set the update info to relayout the whole text.
372     textUpdateInfo.mFullRelayoutNeeded = true;
373     textUpdateInfo.mCharacterIndex     = 0u;
374
375     // Store the size used to layout the text.
376     visualModel->mControlSize = size;
377   }
378
379   // Whether there are modify events.
380   if(0u != impl.mModifyEvents.Count())
381   {
382     // Style operations that need to be done if the text is modified.
383     operationsPending = static_cast<OperationsMask>(operationsPending | COLOR);
384   }
385
386   // Set the update info to elide the text.
387   if(model->mElideEnabled ||
388      ((NULL != impl.mEventData) && impl.mEventData->mIsPlaceholderElideEnabled))
389   {
390     // Update Text layout for applying elided
391     operationsPending                  = static_cast<OperationsMask>(operationsPending |
392                                                     ALIGN |
393                                                     LAYOUT |
394                                                     UPDATE_LAYOUT_SIZE |
395                                                     REORDER);
396     textUpdateInfo.mFullRelayoutNeeded = true;
397     textUpdateInfo.mCharacterIndex     = 0u;
398   }
399
400   bool layoutDirectionChanged = false;
401   if(impl.mLayoutDirection != layoutDirection)
402   {
403     // Flag to indicate that the layout direction has changed.
404     layoutDirectionChanged = true;
405     // Clear the update info. This info will be set the next time the text is updated.
406     textUpdateInfo.mClearAll = true;
407     // Apply modifications to the model
408     // Shape the text again is needed because characters like '()[]{}' have to be mirrored and the glyphs generated again.
409     operationsPending     = static_cast<OperationsMask>(operationsPending |
410                                                     GET_GLYPH_METRICS |
411                                                     SHAPE_TEXT |
412                                                     UPDATE_DIRECTION |
413                                                     ALIGN |
414                                                     LAYOUT |
415                                                     BIDI_INFO |
416                                                     REORDER);
417     impl.mLayoutDirection = layoutDirection;
418   }
419
420   // Make sure the model is up-to-date before layouting.
421   EventHandler::ProcessModifyEvents(controller);
422   bool updated = impl.UpdateModel(operationsPending);
423
424   // Layout the text.
425   Size layoutSize;
426   updated = DoRelayout(impl, size, operationsPending, layoutSize) || updated;
427
428   if(updated)
429   {
430     updateTextType = MODEL_UPDATED;
431   }
432
433   // Do not re-do any operation until something changes.
434   operationsPending          = NO_OPERATION;
435   model->mScrollPositionLast = model->mScrollPosition;
436
437   // Whether the text control is editable
438   const bool isEditable = NULL != impl.mEventData;
439
440   // Keep the current offset as it will be used to update the decorator's positions (if the size changes).
441   Vector2 offset;
442   if(newSize && isEditable)
443   {
444     offset = model->mScrollPosition;
445   }
446
447   if(!isEditable || !controller.IsMultiLineEnabled())
448   {
449     // After doing the text layout, the vertical offset to place the actor in the desired position can be calculated.
450     CalculateVerticalOffset(controller, size);
451   }
452
453   if(isEditable)
454   {
455     if(newSize || layoutDirectionChanged)
456     {
457       // If there is a new size or layout direction is changed, the scroll position needs to be clamped.
458       impl.ClampHorizontalScroll(layoutSize);
459
460       // Update the decorator's positions is needed if there is a new size.
461       impl.mEventData->mDecorator->UpdatePositions(model->mScrollPosition - offset);
462
463       // All decorator elements need to be updated.
464       if(EventData::IsEditingState(impl.mEventData->mState))
465       {
466         impl.mEventData->mScrollAfterUpdatePosition = true;
467         impl.mEventData->mUpdateCursorPosition      = true;
468         impl.mEventData->mUpdateGrabHandlePosition  = true;
469       }
470       else if(impl.mEventData->mState == EventData::SELECTING)
471       {
472         impl.mEventData->mUpdateHighlightBox = true;
473       }
474     }
475
476     // Move the cursor, grab handle etc.
477     if(impl.ProcessInputEvents())
478     {
479       updateTextType = static_cast<UpdateTextType>(updateTextType | DECORATOR_UPDATED);
480     }
481   }
482
483   // Clear the update info. This info will be set the next time the text is updated.
484   textUpdateInfo.Clear();
485   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::Relayout\n");
486
487   return updateTextType;
488 }
489
490 bool Controller::Relayouter::DoRelayout(Controller::Impl& impl, const Size& size, OperationsMask operationsRequired, Size& layoutSize)
491 {
492   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->Controller::Relayouter::DoRelayout %p size %f,%f\n", &impl, size.width, size.height);
493   bool viewUpdated(false);
494
495   // Calculate the operations to be done.
496   const OperationsMask operations = static_cast<OperationsMask>(impl.mOperationsPending & operationsRequired);
497
498   TextUpdateInfo&      textUpdateInfo              = impl.mTextUpdateInfo;
499   const CharacterIndex startIndex                  = textUpdateInfo.mParagraphCharacterIndex;
500   const Length         requestedNumberOfCharacters = textUpdateInfo.mRequestedNumberOfCharacters;
501
502   // Get the current layout size.
503   VisualModelPtr& visualModel = impl.mModel->mVisualModel;
504   layoutSize                  = visualModel->GetLayoutSize();
505
506   if(NO_OPERATION != (LAYOUT & operations))
507   {
508     DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->Controller::DoRelayout LAYOUT & operations\n");
509
510     // Some vectors with data needed to layout and reorder may be void
511     // after the first time the text has been laid out.
512     // Fill the vectors again.
513
514     // Calculate the number of glyphs to layout.
515     const Vector<GlyphIndex>& charactersToGlyph        = visualModel->mCharactersToGlyph;
516     const Vector<Length>&     glyphsPerCharacter       = visualModel->mGlyphsPerCharacter;
517     const GlyphIndex* const   charactersToGlyphBuffer  = charactersToGlyph.Begin();
518     const Length* const       glyphsPerCharacterBuffer = glyphsPerCharacter.Begin();
519
520     const CharacterIndex lastIndex       = startIndex + ((requestedNumberOfCharacters > 0u) ? requestedNumberOfCharacters - 1u : 0u);
521     const GlyphIndex     startGlyphIndex = textUpdateInfo.mStartGlyphIndex;
522
523     // Make sure the index is not out of bound
524     if(charactersToGlyph.Count() != glyphsPerCharacter.Count() ||
525        requestedNumberOfCharacters > charactersToGlyph.Count() ||
526        (lastIndex > charactersToGlyph.Count() && charactersToGlyph.Count() > 0u))
527     {
528       std::string currentText;
529       impl.GetText(currentText);
530
531       DALI_LOG_ERROR("Controller::DoRelayout: Attempting to access invalid buffer\n");
532       DALI_LOG_ERROR("Current text is: %s\n", currentText.c_str());
533       DALI_LOG_ERROR("startIndex: %u, lastIndex: %u, requestedNumberOfCharacters: %u, charactersToGlyph.Count = %lu, glyphsPerCharacter.Count = %lu\n", startIndex, lastIndex, requestedNumberOfCharacters, charactersToGlyph.Count(), glyphsPerCharacter.Count());
534
535       return false;
536     }
537
538     const Length numberOfGlyphs      = (requestedNumberOfCharacters > 0u) ? *(charactersToGlyphBuffer + lastIndex) + *(glyphsPerCharacterBuffer + lastIndex) - startGlyphIndex : 0u;
539     const Length totalNumberOfGlyphs = visualModel->mGlyphs.Count();
540
541     if(0u == totalNumberOfGlyphs)
542     {
543       if(NO_OPERATION != (UPDATE_LAYOUT_SIZE & operations))
544       {
545         visualModel->SetLayoutSize(Size::ZERO);
546       }
547
548       // Nothing else to do if there is no glyphs.
549       DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::DoRelayout no glyphs, view updated true\n");
550       return true;
551     }
552
553     // Set the layout parameters.
554     Layout::Parameters layoutParameters(size, impl.mModel);
555
556     // Resize the vector of positions to have the same size than the vector of glyphs.
557     Vector<Vector2>& glyphPositions = visualModel->mGlyphPositions;
558     glyphPositions.Resize(totalNumberOfGlyphs);
559
560     // Whether the last character is a new paragraph character.
561     const Character* const textBuffer           = impl.mModel->mLogicalModel->mText.Begin();
562     textUpdateInfo.mIsLastCharacterNewParagraph = TextAbstraction::IsNewParagraph(*(textBuffer + (impl.mModel->mLogicalModel->mText.Count() - 1u)));
563     layoutParameters.isLastNewParagraph         = textUpdateInfo.mIsLastCharacterNewParagraph;
564
565     // The initial glyph and the number of glyphs to layout.
566     layoutParameters.startGlyphIndex        = startGlyphIndex;
567     layoutParameters.numberOfGlyphs         = numberOfGlyphs;
568     layoutParameters.startLineIndex         = textUpdateInfo.mStartLineIndex;
569     layoutParameters.estimatedNumberOfLines = textUpdateInfo.mEstimatedNumberOfLines;
570
571     // Update the ellipsis
572     bool elideTextEnabled = impl.mModel->mElideEnabled;
573     auto ellipsisPosition = impl.mModel->mEllipsisPosition;
574
575     if(NULL != impl.mEventData)
576     {
577       if(impl.mEventData->mPlaceholderEllipsisFlag && impl.IsShowingPlaceholderText())
578       {
579         elideTextEnabled = impl.mEventData->mIsPlaceholderElideEnabled;
580       }
581       else if(EventData::INACTIVE != impl.mEventData->mState)
582       {
583         // Disable ellipsis when editing
584         elideTextEnabled = false;
585       }
586
587       // Reset the scroll position in inactive state
588       if(elideTextEnabled && (impl.mEventData->mState == EventData::INACTIVE))
589       {
590         impl.ResetScrollPosition();
591       }
592     }
593
594     // Update the visual model.
595     bool isAutoScrollEnabled = impl.mIsAutoScrollEnabled;
596     Size newLayoutSize;
597     viewUpdated               = impl.mLayoutEngine.LayoutText(layoutParameters,
598                                                 newLayoutSize,
599                                                 elideTextEnabled,
600                                                 isAutoScrollEnabled,
601                                                 ellipsisPosition);
602     impl.mIsAutoScrollEnabled = isAutoScrollEnabled;
603
604     viewUpdated = viewUpdated || (newLayoutSize != layoutSize);
605
606     if(viewUpdated)
607     {
608       layoutSize = newLayoutSize;
609
610       if(NO_OPERATION != (UPDATE_DIRECTION & operations))
611       {
612         impl.mIsTextDirectionRTL = false;
613       }
614
615       if((NO_OPERATION != (UPDATE_DIRECTION & operations)) && !visualModel->mLines.Empty())
616       {
617         impl.mIsTextDirectionRTL = visualModel->mLines[0u].direction;
618       }
619
620       // Sets the layout size.
621       if(NO_OPERATION != (UPDATE_LAYOUT_SIZE & operations))
622       {
623         visualModel->SetLayoutSize(layoutSize);
624       }
625     } // view updated
626   }
627
628   if(NO_OPERATION != (ALIGN & operations))
629   {
630     DoRelayoutHorizontalAlignment(impl, size, startIndex, requestedNumberOfCharacters);
631     viewUpdated = true;
632   }
633 #if defined(DEBUG_ENABLED)
634   std::string currentText;
635   impl.GetText(currentText);
636   DALI_LOG_INFO(gLogFilter, Debug::Concise, "Controller::Relayouter::DoRelayout [%p] mImpl->mIsTextDirectionRTL[%s] [%s]\n", &impl, (impl.mIsTextDirectionRTL) ? "true" : "false", currentText.c_str());
637 #endif
638   DALI_LOG_INFO(gLogFilter, Debug::Verbose, "<--Controller::Relayouter::DoRelayout, view updated %s\n", (viewUpdated ? "true" : "false"));
639   return viewUpdated;
640 }
641
642 void Controller::Relayouter::DoRelayoutHorizontalAlignment(Controller::Impl&    impl,
643                                                            const Size&          size,
644                                                            const CharacterIndex startIndex,
645                                                            const Length         requestedNumberOfCharacters)
646 {
647   // The visualModel
648   VisualModelPtr& visualModel = impl.mModel->mVisualModel;
649
650   // The laid-out lines.
651   Vector<LineRun>& lines = visualModel->mLines;
652
653   CharacterIndex alignStartIndex                  = startIndex;
654   Length         alignRequestedNumberOfCharacters = requestedNumberOfCharacters;
655
656   // the whole text needs to be full aligned.
657   // If you do not do a full aligned, only the last line of the multiline input is aligned.
658   if(impl.mEventData && impl.mEventData->mUpdateAlignment)
659   {
660     alignStartIndex                   = 0u;
661     alignRequestedNumberOfCharacters  = impl.mModel->mLogicalModel->mText.Count();
662     impl.mEventData->mUpdateAlignment = false;
663   }
664
665   // If there is no BoundedParagraphRuns then apply the alignment of controller.
666   // Check whether the layout is single line. It's needed to apply one alignment for single-line.
667   // In single-line layout case we need to check whether to follow the alignment of controller or the first BoundedParagraph.
668   // Apply BoundedParagraph's alignment if and only if there is one BoundedParagraph contains all characters. Otherwise follow controller's alignment.
669   const bool isFollowControllerAlignment = ((impl.mModel->GetNumberOfBoundedParagraphRuns() == 0u) ||
670                                             ((Layout::Engine::SINGLE_LINE_BOX == impl.mLayoutEngine.GetLayout()) &&
671                                              (impl.mModel->GetBoundedParagraphRuns()[0].characterRun.numberOfCharacters != impl.mModel->mLogicalModel->mText.Count())));
672
673   if(isFollowControllerAlignment)
674   {
675     // Need to align with the control's size as the text may contain lines
676     // starting either with left to right text or right to left.
677     impl.mLayoutEngine.Align(size,
678                              alignStartIndex,
679                              alignRequestedNumberOfCharacters,
680                              impl.mModel->mHorizontalAlignment,
681                              lines,
682                              impl.mModel->mAlignmentOffset,
683                              impl.mLayoutDirection,
684                              (impl.mModel->mMatchLayoutDirection != DevelText::MatchLayoutDirection::CONTENTS));
685   }
686   else
687   {
688     //Override the controller horizontal-alignment by horizontal-alignment of bounded paragraph.
689     const Length&                      numberOfBoundedParagraphRuns = impl.mModel->GetNumberOfBoundedParagraphRuns();
690     const Vector<BoundedParagraphRun>& boundedParagraphRuns         = impl.mModel->GetBoundedParagraphRuns();
691     const CharacterIndex               alignEndIndex                = alignStartIndex + alignRequestedNumberOfCharacters - 1u;
692
693     Length alignIndex               = alignStartIndex;
694     Length boundedParagraphRunIndex = 0u;
695
696     while(alignIndex <= alignEndIndex && boundedParagraphRunIndex < numberOfBoundedParagraphRuns)
697     {
698       //BP: BoundedParagraph
699       const BoundedParagraphRun& boundedParagraphRun   = boundedParagraphRuns[boundedParagraphRunIndex];
700       const CharacterIndex&      characterStartIndexBP = boundedParagraphRun.characterRun.characterIndex;
701       const Length&              numberOfCharactersBP  = boundedParagraphRun.characterRun.numberOfCharacters;
702       const CharacterIndex       characterEndIndexBP   = characterStartIndexBP + numberOfCharactersBP - 1u;
703
704       CharacterIndex                  decidedAlignStartIndex         = alignIndex;
705       Length                          decidedAlignNumberOfCharacters = alignEndIndex - alignIndex + 1u;
706       Text::HorizontalAlignment::Type decidedHorizontalAlignment     = impl.mModel->mHorizontalAlignment;
707
708       /*
709          * Shortcuts to explain indexes cases:
710          *
711          * AS: Alignment Start Index
712          * AE: Alignment End Index
713          * PS: Paragraph Start Index
714          * PE: Paragraph End Index
715          * B: BoundedParagraph Alignment
716          * M: Model Alignment
717          *
718          */
719
720       if(alignIndex < characterStartIndexBP && characterStartIndexBP <= alignEndIndex) /// AS.MMMMMM.PS--------AE
721       {
722         // Alignment from "Alignment Start Index" to index before "Paragraph Start Index" according to "Model Alignment"
723         decidedAlignStartIndex         = alignIndex;
724         decidedAlignNumberOfCharacters = characterStartIndexBP - alignIndex;
725         decidedHorizontalAlignment     = impl.mModel->mHorizontalAlignment;
726
727         // Need to re-heck the case of current bounded paragraph
728         alignIndex = characterStartIndexBP; // Shift AS to be PS
729       }
730       else if((characterStartIndexBP <= alignIndex && alignIndex <= characterEndIndexBP) ||     /// ---PS.BBBBBBB.AS.BBBBBBB.PE---
731               (characterStartIndexBP <= alignEndIndex && alignEndIndex <= characterEndIndexBP)) /// ---PS.BBBBBB.AE.BBBBBBB.PE---
732       {
733         // Alignment from "Paragraph Start Index" to "Paragraph End Index" according to "BoundedParagraph Alignment"
734         decidedAlignStartIndex         = characterStartIndexBP;
735         decidedAlignNumberOfCharacters = numberOfCharactersBP;
736         decidedHorizontalAlignment     = boundedParagraphRun.horizontalAlignmentDefined ? boundedParagraphRun.horizontalAlignment : impl.mModel->mHorizontalAlignment;
737
738         alignIndex = characterEndIndexBP + 1u; // Shift AS to be after PE direct
739         boundedParagraphRunIndex++;            // Align then check the case of next bounded paragraph
740       }
741       else
742       {
743         boundedParagraphRunIndex++; // Check the case of next bounded paragraph
744         continue;
745       }
746
747       impl.mLayoutEngine.Align(size,
748                                decidedAlignStartIndex,
749                                decidedAlignNumberOfCharacters,
750                                decidedHorizontalAlignment,
751                                lines,
752                                impl.mModel->mAlignmentOffset,
753                                impl.mLayoutDirection,
754                                (impl.mModel->mMatchLayoutDirection != DevelText::MatchLayoutDirection::CONTENTS));
755     }
756
757     //Align the remaining that is not aligned
758     if(alignIndex <= alignEndIndex)
759     {
760       impl.mLayoutEngine.Align(size,
761                                alignIndex,
762                                (alignEndIndex - alignIndex + 1u),
763                                impl.mModel->mHorizontalAlignment,
764                                lines,
765                                impl.mModel->mAlignmentOffset,
766                                impl.mLayoutDirection,
767                                (impl.mModel->mMatchLayoutDirection != DevelText::MatchLayoutDirection::CONTENTS));
768     }
769   }
770 }
771
772 void Controller::Relayouter::CalculateVerticalOffset(Controller& controller, const Size& controlSize)
773 {
774   Controller::Impl& impl                  = *controller.mImpl;
775   ModelPtr&         model                 = impl.mModel;
776   VisualModelPtr&   visualModel           = model->mVisualModel;
777   Size              layoutSize            = model->mVisualModel->GetLayoutSize();
778   Size              oldLayoutSize         = layoutSize;
779   float             offsetY               = 0.f;
780   bool              needRecalc            = false;
781   float             defaultFontLineHeight = impl.GetDefaultFontLineHeight();
782
783   if(fabsf(layoutSize.height) < Math::MACHINE_EPSILON_1000)
784   {
785     // Get the line height of the default font.
786     layoutSize.height = defaultFontLineHeight;
787   }
788
789   // Whether the text control is editable
790   const bool isEditable = NULL != impl.mEventData;
791   if(isEditable && layoutSize.height != defaultFontLineHeight && impl.IsShowingPlaceholderText())
792   {
793     // This code prevents the wrong positioning of cursor when the layout size is bigger/smaller than defaultFontLineHeight.
794     // This situation occurs when the size of placeholder text is different from the default text.
795     layoutSize.height = defaultFontLineHeight;
796     needRecalc        = true;
797   }
798
799   switch(model->mVerticalAlignment)
800   {
801     case VerticalAlignment::TOP:
802     {
803       model->mScrollPosition.y = 0.f;
804       offsetY                  = 0.f;
805       break;
806     }
807     case VerticalAlignment::CENTER:
808     {
809       model->mScrollPosition.y = floorf(0.5f * (controlSize.height - layoutSize.height)); // try to avoid pixel alignment.
810       if(needRecalc) offsetY = floorf(0.5f * (layoutSize.height - oldLayoutSize.height));
811       break;
812     }
813     case VerticalAlignment::BOTTOM:
814     {
815       model->mScrollPosition.y = controlSize.height - layoutSize.height;
816       if(needRecalc) offsetY = layoutSize.height - oldLayoutSize.height;
817       break;
818     }
819   }
820
821   if(needRecalc)
822   {
823     // Update glyphPositions according to recalculation.
824     const Length     positionCount  = visualModel->mGlyphPositions.Count();
825     Vector<Vector2>& glyphPositions = visualModel->mGlyphPositions;
826     for(Length index = 0u; index < positionCount; index++)
827     {
828       glyphPositions[index].y += offsetY;
829     }
830   }
831 }
832
833 } // namespace Text
834
835 } // namespace Toolkit
836
837 } // namespace Dali