2 * Copyright (c) 2017 Samsung Electronics Co., Ltd.
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 #include <dali-toolkit/internal/text/layouts/layout-engine.h>
23 #include <dali/integration-api/debug.h>
24 #include <dali/devel-api/text-abstraction/font-client.h>
27 #include <dali-toolkit/internal/text/bidirectional-line-info-run.h>
28 #include <dali-toolkit/internal/text/cursor-helper-functions.h>
29 #include <dali-toolkit/internal/text/glyph-metrics-helper.h>
30 #include <dali-toolkit/internal/text/layouts/layout-parameters.h>
47 #if defined(DEBUG_ENABLED)
48 Debug::Filter* gLogFilter = Debug::Filter::New(Debug::Concise, true, "LOG_TEXT_LAYOUT");
51 const float MAX_FLOAT = std::numeric_limits<float>::max();
52 const bool RTL = true;
53 const float CURSOR_WIDTH = 1.f;
54 const float LINE_SPACING= 0.f;
59 * @brief Stores temporary layout info of the line.
67 numberOfCharacters( 0u ),
71 wsLengthEndOfLine( 0.f ),
73 descender( MAX_FLOAT ),
85 numberOfCharacters = 0u;
89 wsLengthEndOfLine = 0.f;
91 descender = MAX_FLOAT;
94 GlyphIndex glyphIndex; ///< Index of the first glyph to be laid-out.
95 CharacterIndex characterIndex; ///< Index of the first character to be laid-out.
96 Length numberOfGlyphs; ///< The number of glyph which fit in one line.
97 Length numberOfCharacters; ///< The number of characters which fit in one line.
98 float length; ///< The addition of the advance metric of all the glyphs which fit in one line.
99 float extraBearing; ///< The extra width to be added to the line's length when the bearing of the first glyph is negative.
100 float extraWidth; ///< The extra width to be added to the line's length when the bearing + width of the last glyph is greater than the advance.
101 float wsLengthEndOfLine; ///< The length of the white spaces at the end of the line.
102 float ascender; ///< The maximum ascender of all fonts in the line.
103 float descender; ///< The minimum descender of all fonts in the line.
104 float lineSpacing; ///< The line spacing
110 : mLayout( Layout::Engine::SINGLE_LINE_BOX ),
111 mCursorWidth( CURSOR_WIDTH ),
112 mDefaultLineSpacing( LINE_SPACING ),
113 mPreviousCharacterExtraWidth( 0.0f )
118 * @brief Updates the line ascender and descender with the metrics of a new font.
120 * @param[in] fontId The id of the new font.
121 * @param[in,out] lineLayout The line layout.
123 void UpdateLineHeight( FontId fontId, LineLayout& lineLayout )
125 Text::FontMetrics fontMetrics;
126 mMetrics->GetFontMetrics( fontId, fontMetrics );
128 // Sets the maximum ascender.
129 if( fontMetrics.ascender > lineLayout.ascender )
131 lineLayout.ascender = fontMetrics.ascender;
134 // Sets the minimum descender.
135 if( fontMetrics.descender < lineLayout.descender )
137 lineLayout.descender = fontMetrics.descender;
140 // set the line spacing
141 lineLayout.lineSpacing = mDefaultLineSpacing;
145 * @brief Merges a temporary line layout into the line layout.
147 * @param[in,out] lineLayout The line layout.
148 * @param[in] tmpLineLayout A temporary line layout.
150 void MergeLineLayout( LineLayout& lineLayout,
151 const LineLayout& tmpLineLayout )
153 lineLayout.numberOfCharacters += tmpLineLayout.numberOfCharacters;
154 lineLayout.numberOfGlyphs += tmpLineLayout.numberOfGlyphs;
155 lineLayout.length += tmpLineLayout.length;
157 if( 0.f < tmpLineLayout.length )
159 lineLayout.length += lineLayout.wsLengthEndOfLine;
161 lineLayout.wsLengthEndOfLine = tmpLineLayout.wsLengthEndOfLine;
165 lineLayout.wsLengthEndOfLine += tmpLineLayout.wsLengthEndOfLine;
168 if( tmpLineLayout.ascender > lineLayout.ascender )
170 lineLayout.ascender = tmpLineLayout.ascender;
173 if( tmpLineLayout.descender < lineLayout.descender )
175 lineLayout.descender = tmpLineLayout.descender;
180 * Retrieves the line layout for a given box width.
182 * @note This method lais out text as it were left to right. At this point is not possible to reorder the line
183 * because the number of characters of the line is not known (one of the responsabilities of this method
184 * is calculate that). Due to glyph's 'x' bearing, width and advance, when right to left or mixed right to left
185 * and left to right text is laid-out, it can be small differences in the line length. One solution is to
186 * reorder and re-lay out the text after this method and add or remove one extra glyph if needed. However,
187 * this method calculates which are the first and last glyphs of the line (the ones that causes the
188 * differences). This is a good point to check if there is problems with the text exceeding the boundaries
189 * of the control when there is right to left text.
191 * @param[in] parameters The layout parameters.
192 * @param[out] lineLayout The line layout.
193 * @param[in,out] paragraphDirection in: the current paragraph's direction, out: the next paragraph's direction. Is set after a must break.
194 * @param[in] completelyFill Whether to completely fill the line ( even if the last word exceeds the boundaries ).
196 void GetLineLayoutForBox( const Parameters& parameters,
197 LineLayout& lineLayout,
198 CharacterDirection& paragraphDirection,
199 bool completelyFill )
201 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "-->GetLineLayoutForBox\n" );
202 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " initial glyph index : %d\n", lineLayout.glyphIndex );
203 // Stores temporary line layout which has not been added to the final line layout.
204 LineLayout tmpLineLayout;
206 const bool isMultiline = mLayout == MULTI_LINE_BOX;
207 const bool isWordLaidOut = parameters.lineWrapMode == Text::LineWrap::WORD;
209 // The last glyph to be laid-out.
210 const GlyphIndex lastGlyphOfParagraphPlusOne = parameters.startGlyphIndex + parameters.numberOfGlyphs;
212 // If the first glyph has a negative bearing its absolute value needs to be added to the line length.
213 // In the case the line starts with a right to left character, if the width is longer than the advance,
214 // the difference needs to be added to the line length.
216 // Check whether the first glyph comes from a character that is shaped in multiple glyphs.
217 const Length numberOfGLyphsInGroup = GetNumberOfGlyphsOfGroup( lineLayout.glyphIndex,
218 lastGlyphOfParagraphPlusOne,
219 parameters.charactersPerGlyphBuffer );
221 GlyphMetrics glyphMetrics;
222 GetGlyphsMetrics( lineLayout.glyphIndex,
223 numberOfGLyphsInGroup,
225 parameters.glyphsBuffer,
228 // Set the direction of the first character of the line.
229 lineLayout.characterIndex = *( parameters.glyphsToCharactersBuffer + lineLayout.glyphIndex );
230 const CharacterDirection firstCharacterDirection = ( NULL == parameters.characterDirectionBuffer ) ? false : *( parameters.characterDirectionBuffer + lineLayout.characterIndex );
231 CharacterDirection previousCharacterDirection = firstCharacterDirection;
233 const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
234 float tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
236 float tmpExtraBearing = ( 0.f > glyphMetrics.xBearing ) ? -glyphMetrics.xBearing : 0.f;
238 tmpLineLayout.length += mCursorWidth; // Added to give some space to the cursor.
240 // Calculate the line height if there is no characters.
241 FontId lastFontId = glyphMetrics.fontId;
242 UpdateLineHeight( lastFontId, tmpLineLayout );
244 bool oneWordLaidOut = false;
246 for( GlyphIndex glyphIndex = lineLayout.glyphIndex;
247 glyphIndex < lastGlyphOfParagraphPlusOne; )
249 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " glyph index : %d\n", glyphIndex );
251 // Check whether this glyph comes from a character that is shaped in multiple glyphs.
252 const Length numberOfGLyphsInGroup = GetNumberOfGlyphsOfGroup( glyphIndex,
253 lastGlyphOfParagraphPlusOne,
254 parameters.charactersPerGlyphBuffer );
256 GlyphMetrics glyphMetrics;
257 GetGlyphsMetrics( glyphIndex,
258 numberOfGLyphsInGroup,
260 parameters.glyphsBuffer,
263 const bool isLastGlyph = glyphIndex + numberOfGLyphsInGroup == parameters.totalNumberOfGlyphs;
265 // Check if the font of the current glyph is the same of the previous one.
266 // If it's different the ascender and descender need to be updated.
267 if( lastFontId != glyphMetrics.fontId )
269 UpdateLineHeight( glyphMetrics.fontId, tmpLineLayout );
270 lastFontId = glyphMetrics.fontId;
273 // Get the character indices for the current glyph. The last character index is needed
274 // because there are glyphs formed by more than one character but their break info is
275 // given only for the last character.
276 const Length charactersPerGlyph = *( parameters.charactersPerGlyphBuffer + glyphIndex + numberOfGLyphsInGroup - 1u );
277 const bool hasCharacters = charactersPerGlyph > 0u;
278 const CharacterIndex characterFirstIndex = *( parameters.glyphsToCharactersBuffer + glyphIndex );
279 const CharacterIndex characterLastIndex = characterFirstIndex + ( hasCharacters ? charactersPerGlyph - 1u : 0u );
281 // Get the line break info for the current character.
282 const LineBreakInfo lineBreakInfo = hasCharacters ? *( parameters.lineBreakInfoBuffer + characterLastIndex ) : TextAbstraction::LINE_NO_BREAK;
284 // Increase the number of characters.
285 tmpLineLayout.numberOfCharacters += charactersPerGlyph;
287 // Increase the number of glyphs.
288 tmpLineLayout.numberOfGlyphs += numberOfGLyphsInGroup;
290 // Check whether is a white space.
291 const Character character = *( parameters.textBuffer + characterFirstIndex );
292 const bool isWhiteSpace = TextAbstraction::IsWhiteSpace( character );
294 // Used to restore the temporal line layout when a single word does not fit in the control's width and is split by character.
295 const float previousTmpLineLength = tmpLineLayout.length;
296 const float previousTmpExtraBearing = tmpExtraBearing;
297 const float previousTmpExtraWidth = tmpExtraWidth;
299 // Get the character's direction.
300 const CharacterDirection characterDirection = ( NULL == parameters.characterDirectionBuffer ) ? false : *( parameters.characterDirectionBuffer + characterFirstIndex );
302 // Increase the accumulated length.
305 // Add the length to the length of white spaces at the end of the line.
306 tmpLineLayout.wsLengthEndOfLine += glyphMetrics.advance; // The advance is used as the width is always zero for the white spaces.
310 // Add as well any previous white space length.
311 tmpLineLayout.length += tmpLineLayout.wsLengthEndOfLine + glyphMetrics.advance;
313 // An extra space may be added to the line for the first and last glyph of the line.
314 // If the bearing of the first glyph is negative, its positive value needs to be added.
315 // If the bearing plus the width of the last glyph is greater than the advance, the difference
316 // needs to be added.
318 if( characterDirection == paragraphDirection )
320 if( RTL == characterDirection )
331 tmpExtraBearing = ( 0.f > glyphMetrics.xBearing ) ? -glyphMetrics.xBearing : 0.f;
344 const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
345 tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
346 tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
351 if( characterDirection != previousCharacterDirection )
353 if( RTL == characterDirection )
358 const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
359 tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
360 tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
367 tmpExtraBearing = ( 0.f > glyphMetrics.xBearing ) ? -glyphMetrics.xBearing : 0.f;
370 else if( characterDirection == firstCharacterDirection )
372 if( RTL == characterDirection )
378 tmpExtraBearing = ( 0.f > glyphMetrics.xBearing ) ? -glyphMetrics.xBearing : 0.f;
386 const float extraWidth = glyphMetrics.xBearing + glyphMetrics.width - glyphMetrics.advance;
387 tmpExtraWidth = ( 0.f < extraWidth ) ? extraWidth : 0.f;
388 tmpExtraWidth = std::max( mPreviousCharacterExtraWidth - glyphMetrics.advance, tmpExtraWidth );
393 // Clear the white space length at the end of the line.
394 tmpLineLayout.wsLengthEndOfLine = 0.f;
397 // If calculation is end but wsLengthEndOfLine is exist, it means end of text is space.
398 // Merge remained length.
399 if ( !parameters.ignoreSpaceAfterText && glyphIndex == lastGlyphOfParagraphPlusOne-1 && tmpLineLayout.wsLengthEndOfLine > 0 )
401 tmpLineLayout.length += tmpLineLayout.wsLengthEndOfLine;
402 tmpLineLayout.wsLengthEndOfLine = 0u;
405 // Save the current extra width to compare with the next one
406 mPreviousCharacterExtraWidth = tmpExtraWidth;
408 // Check if the accumulated length fits in the width of the box.
409 if( ( completelyFill || isMultiline ) && !(parameters.ignoreSpaceAfterText && isWhiteSpace) &&
410 ( tmpExtraBearing + lineLayout.length + lineLayout.wsLengthEndOfLine + tmpLineLayout.length + tmpExtraWidth > parameters.boundingBox.width ) )
412 // Current word does not fit in the box's width.
413 if( !oneWordLaidOut || completelyFill )
415 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " Break the word by character\n" );
417 // The word doesn't fit in the control's width. It needs to be split by character.
418 if( tmpLineLayout.numberOfGlyphs > 0u )
420 tmpLineLayout.numberOfCharacters -= charactersPerGlyph;
421 tmpLineLayout.numberOfGlyphs -= numberOfGLyphsInGroup;
422 tmpLineLayout.length = previousTmpLineLength;
423 tmpExtraBearing = previousTmpExtraBearing;
424 tmpExtraWidth = previousTmpExtraWidth;
427 // Add part of the word to the line layout.
428 MergeLineLayout( lineLayout, tmpLineLayout );
432 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " Current word does not fit.\n" );
435 lineLayout.extraBearing = tmpExtraBearing;
436 lineLayout.extraWidth = tmpExtraWidth;
438 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox.\n" );
443 if( ( isMultiline || isLastGlyph ) &&
444 ( TextAbstraction::LINE_MUST_BREAK == lineBreakInfo ) )
446 // Must break the line. Update the line layout and return.
447 MergeLineLayout( lineLayout, tmpLineLayout );
449 // Set the next paragraph's direction.
451 ( NULL != parameters.characterDirectionBuffer ) )
453 paragraphDirection = *( parameters.characterDirectionBuffer + 1u + characterLastIndex );
456 lineLayout.extraBearing = tmpExtraBearing;
457 lineLayout.extraWidth = tmpExtraWidth;
459 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " Must break\n" );
460 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox\n" );
466 ( TextAbstraction::LINE_ALLOW_BREAK == lineBreakInfo ) )
468 oneWordLaidOut = isWordLaidOut;
469 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " One word laid-out\n" );
471 // Current glyph is the last one of the current word.
472 // Add the temporal layout to the current one.
473 MergeLineLayout( lineLayout, tmpLineLayout );
475 tmpLineLayout.Clear();
478 previousCharacterDirection = characterDirection;
479 glyphIndex += numberOfGLyphsInGroup;
482 lineLayout.extraBearing = tmpExtraBearing;
483 lineLayout.extraWidth = tmpExtraWidth;
485 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--GetLineLayoutForBox\n" );
488 void SetGlyphPositions( const GlyphInfo* const glyphsBuffer,
489 Length numberOfGlyphs,
491 Vector2* glyphPositionsBuffer )
493 // Traverse the glyphs and set the positions.
495 // Check if the x bearing of the first character is negative.
496 // If it has a negative x bearing, it will exceed the boundaries of the actor,
497 // so the penX position needs to be moved to the right.
499 const GlyphInfo& glyph = *glyphsBuffer;
500 float penX = ( 0.f > glyph.xBearing ) ? -glyph.xBearing + outlineWidth : outlineWidth;
503 for( GlyphIndex i = 0u; i < numberOfGlyphs; ++i )
505 const GlyphInfo& glyph = *( glyphsBuffer + i );
506 Vector2& position = *( glyphPositionsBuffer + i );
508 position.x = penX + glyph.xBearing;
509 position.y = -glyph.yBearing;
511 penX += glyph.advance;
516 * @brief Resizes the line buffer.
518 * @param[in,out] lines The vector of lines. Used when the layout is created from scratch.
519 * @param[in,out] newLines The vector of lines used instead of @p lines when the layout is updated.
520 * @param[in,out] linesCapacity The capacity of the vector (either lines or newLines).
521 * @param[in] updateCurrentBuffer Whether the layout is updated.
523 * @return Pointer to either lines or newLines.
525 LineRun* ResizeLinesBuffer( Vector<LineRun>& lines,
526 Vector<LineRun>& newLines,
527 Length& linesCapacity,
528 bool updateCurrentBuffer )
530 LineRun* linesBuffer = NULL;
531 // Reserve more space for the next lines.
533 if( updateCurrentBuffer )
535 newLines.Resize( linesCapacity );
536 linesBuffer = newLines.Begin();
540 lines.Resize( linesCapacity );
541 linesBuffer = lines.Begin();
548 * Ellipsis a line if it exceeds the width's of the bounding box.
550 * @param[in] layoutParameters The parameters needed to layout the text.
551 * @param[in] layout The line layout.
552 * @param[in,out] layoutSize The text's layout size.
553 * @param[in,out] linesBuffer Pointer to the line's buffer.
554 * @param[in,out] glyphPositionsBuffer Pointer to the position's buffer.
555 * @param[in,out] numberOfLines The number of laid-out lines.
556 * @param[in] penY The vertical layout position.
557 * @param[in] currentParagraphDirection The current paragraph's direction.
559 * return Whether the line is ellipsized.
561 bool EllipsisLine( const Parameters& layoutParameters,
562 const LineLayout& layout,
564 LineRun* linesBuffer,
565 Vector2* glyphPositionsBuffer,
566 Length& numberOfLines,
568 CharacterDirection currentParagraphDirection )
570 const bool ellipsis = ( ( penY - layout.descender > layoutParameters.boundingBox.height ) ||
571 ( ( mLayout == SINGLE_LINE_BOX ) &&
572 ( layout.extraBearing + layout.length + layout.extraWidth > layoutParameters.boundingBox.width ) ) );
576 // Do not layout more lines if ellipsis is enabled.
578 // The last line needs to be completely filled with characters.
579 // Part of a word may be used.
581 LineRun* lineRun = NULL;
582 LineLayout ellipsisLayout;
583 if( 0u != numberOfLines )
585 // Get the last line and layout it again with the 'completelyFill' flag to true.
586 lineRun = linesBuffer + ( numberOfLines - 1u );
588 penY -= layout.ascender - lineRun->descender + lineRun->lineSpacing;
590 ellipsisLayout.glyphIndex = lineRun->glyphRun.glyphIndex;
594 // At least there is space reserved for one line.
595 lineRun = linesBuffer;
597 lineRun->glyphRun.glyphIndex = 0u;
598 ellipsisLayout.glyphIndex = 0u;
603 GetLineLayoutForBox( layoutParameters,
605 currentParagraphDirection,
608 lineRun->glyphRun.numberOfGlyphs = ellipsisLayout.numberOfGlyphs;
609 lineRun->characterRun.characterIndex = ellipsisLayout.characterIndex;
610 lineRun->characterRun.numberOfCharacters = ellipsisLayout.numberOfCharacters;
611 lineRun->width = ellipsisLayout.length;
612 lineRun->extraLength = ( ellipsisLayout.wsLengthEndOfLine > 0.f ) ? ellipsisLayout.wsLengthEndOfLine - ellipsisLayout.extraWidth : 0.f;
613 lineRun->ascender = ellipsisLayout.ascender;
614 lineRun->descender = ellipsisLayout.descender;
615 lineRun->direction = !RTL;
616 lineRun->ellipsis = true;
618 layoutSize.width = layoutParameters.boundingBox.width;
619 if( layoutSize.height < Math::MACHINE_EPSILON_1000 )
621 layoutSize.height += ( lineRun->ascender + -lineRun->descender ) + lineRun->lineSpacing;
624 SetGlyphPositions( layoutParameters.glyphsBuffer + lineRun->glyphRun.glyphIndex,
625 ellipsisLayout.numberOfGlyphs,
626 layoutParameters.outlineWidth,
627 glyphPositionsBuffer + lineRun->glyphRun.glyphIndex - layoutParameters.startGlyphIndex );
634 * @brief Updates the text layout with a new laid-out line.
636 * @param[in] layoutParameters The parameters needed to layout the text.
637 * @param[in] layout The line layout.
638 * @param[in,out] layoutSize The text's layout size.
639 * @param[in,out] linesBuffer Pointer to the line's buffer.
640 * @param[in] index Index to the vector of glyphs.
641 * @param[in,out] numberOfLines The number of laid-out lines.
642 * @param[in] isLastLine Whether the laid-out line is the last one.
644 void UpdateTextLayout( const Parameters& layoutParameters,
645 const LineLayout& layout,
647 LineRun* linesBuffer,
649 Length& numberOfLines,
652 LineRun& lineRun = *( linesBuffer + numberOfLines );
655 lineRun.glyphRun.glyphIndex = index;
656 lineRun.glyphRun.numberOfGlyphs = layout.numberOfGlyphs;
657 lineRun.characterRun.characterIndex = layout.characterIndex;
658 lineRun.characterRun.numberOfCharacters = layout.numberOfCharacters;
659 lineRun.lineSpacing = mDefaultLineSpacing;
661 if( isLastLine && !layoutParameters.isLastNewParagraph )
663 const float width = layout.extraBearing + layout.length + layout.extraWidth + layout.wsLengthEndOfLine;
664 if( MULTI_LINE_BOX == mLayout )
666 lineRun.width = ( width > layoutParameters.boundingBox.width ) ? layoutParameters.boundingBox.width : width;
670 lineRun.width = width;
673 lineRun.extraLength = 0.f;
677 lineRun.width = layout.extraBearing + layout.length + layout.extraWidth;
678 lineRun.extraLength = ( layout.wsLengthEndOfLine > 0.f ) ? layout.wsLengthEndOfLine - layout.extraWidth : 0.f;
680 lineRun.ascender = layout.ascender;
681 lineRun.descender = layout.descender;
682 lineRun.direction = !RTL;
683 lineRun.ellipsis = false;
685 // Update the actual size.
686 if( lineRun.width > layoutSize.width )
688 layoutSize.width = lineRun.width;
691 layoutSize.height += ( lineRun.ascender + -lineRun.descender ) + lineRun.lineSpacing;
695 * @brief Updates the text layout with the last laid-out line.
697 * @param[in] layoutParameters The parameters needed to layout the text.
698 * @param[in] characterIndex The character index of the line.
699 * @param[in] glyphIndex The glyph index of the line.
700 * @param[in,out] layoutSize The text's layout size.
701 * @param[in,out] linesBuffer Pointer to the line's buffer.
702 * @param[in,out] numberOfLines The number of laid-out lines.
704 void UpdateTextLayout( const Parameters& layoutParameters,
705 CharacterIndex characterIndex,
706 GlyphIndex glyphIndex,
708 LineRun* linesBuffer,
709 Length& numberOfLines )
711 // Need to add a new line with no characters but with height to increase the layoutSize.height
712 const GlyphInfo& glyphInfo = *( layoutParameters.glyphsBuffer + layoutParameters.totalNumberOfGlyphs - 1u );
714 Text::FontMetrics fontMetrics;
715 mMetrics->GetFontMetrics( glyphInfo.fontId, fontMetrics );
717 LineRun& lineRun = *( linesBuffer + numberOfLines );
720 lineRun.glyphRun.glyphIndex = glyphIndex;
721 lineRun.glyphRun.numberOfGlyphs = 0u;
722 lineRun.characterRun.characterIndex = characterIndex;
723 lineRun.characterRun.numberOfCharacters = 0u;
725 lineRun.ascender = fontMetrics.ascender;
726 lineRun.descender = fontMetrics.descender;
727 lineRun.extraLength = 0.f;
728 lineRun.alignmentOffset = 0.f;
729 lineRun.direction = !RTL;
730 lineRun.ellipsis = false;
731 lineRun.lineSpacing = mDefaultLineSpacing;
733 layoutSize.height += ( lineRun.ascender + -lineRun.descender ) + lineRun.lineSpacing;
737 * @brief Updates the text's layout size adding the size of the previously laid-out lines.
739 * @param[in] lines The vector of lines (before the new laid-out lines are inserted).
740 * @param[in,out] layoutSize The text's layout size.
742 void UpdateLayoutSize( const Vector<LineRun>& lines,
745 for( Vector<LineRun>::ConstIterator it = lines.Begin(),
750 const LineRun& line = *it;
752 if( line.width > layoutSize.width )
754 layoutSize.width = line.width;
757 layoutSize.height += ( line.ascender + -line.descender ) + line.lineSpacing;
762 * @brief Updates the indices of the character and glyph runs of the lines before the new lines are inserted.
764 * @param[in] layoutParameters The parameters needed to layout the text.
765 * @param[in,out] lines The vector of lines (before the new laid-out lines are inserted).
766 * @param[in] characterOffset The offset to be added to the runs of characters.
767 * @param[in] glyphOffset The offset to be added to the runs of glyphs.
769 void UpdateLineIndexOffsets( const Parameters& layoutParameters,
770 Vector<LineRun>& lines,
771 Length characterOffset,
774 // Update the glyph and character runs.
775 for( Vector<LineRun>::Iterator it = lines.Begin() + layoutParameters.startLineIndex,
782 line.glyphRun.glyphIndex = glyphOffset;
783 line.characterRun.characterIndex = characterOffset;
785 glyphOffset += line.glyphRun.numberOfGlyphs;
786 characterOffset += line.characterRun.numberOfCharacters;
790 bool LayoutText( const Parameters& layoutParameters,
791 Vector<Vector2>& glyphPositions,
792 Vector<LineRun>& lines,
794 bool elideTextEnabled )
796 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "-->LayoutText\n" );
797 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " box size %f, %f\n", layoutParameters.boundingBox.width, layoutParameters.boundingBox.height );
799 if( 0u == layoutParameters.numberOfGlyphs )
801 // Add an extra line if the last character is a new paragraph character and the last line doesn't have zero characters.
802 if( layoutParameters.isLastNewParagraph )
804 Length numberOfLines = lines.Count();
805 if( 0u != numberOfLines )
807 const LineRun& lastLine = *( lines.End() - 1u );
809 if( 0u != lastLine.characterRun.numberOfCharacters )
811 // Need to add a new line with no characters but with height to increase the layoutSize.height
813 Initialize( newLine );
814 lines.PushBack( newLine );
816 UpdateTextLayout( layoutParameters,
817 lastLine.characterRun.characterIndex + lastLine.characterRun.numberOfCharacters,
818 lastLine.glyphRun.glyphIndex + lastLine.glyphRun.numberOfGlyphs,
826 // Calculates the layout size.
827 UpdateLayoutSize( lines,
830 // Nothing else do if there are no glyphs to layout.
834 const GlyphIndex lastGlyphPlusOne = layoutParameters.startGlyphIndex + layoutParameters.numberOfGlyphs;
836 // In a previous layout, an extra line with no characters may have been added if the text ended with a new paragraph character.
837 // This extra line needs to be removed.
838 if( 0u != lines.Count() )
840 Vector<LineRun>::Iterator lastLine = lines.End() - 1u;
842 if( ( 0u == lastLine->characterRun.numberOfCharacters ) &&
843 ( lastGlyphPlusOne == layoutParameters.totalNumberOfGlyphs ) )
845 lines.Remove( lastLine );
849 // Set the first paragraph's direction.
850 CharacterDirection paragraphDirection = ( NULL != layoutParameters.characterDirectionBuffer ) ? *layoutParameters.characterDirectionBuffer : !RTL;
852 // Whether the layout is being updated or set from scratch.
853 const bool updateCurrentBuffer = layoutParameters.numberOfGlyphs < layoutParameters.totalNumberOfGlyphs;
855 Vector2* glyphPositionsBuffer = NULL;
856 Vector<Vector2> newGlyphPositions;
858 LineRun* linesBuffer = NULL;
859 Vector<LineRun> newLines;
861 // Estimate the number of lines.
862 Length linesCapacity = std::max( 1u, layoutParameters.estimatedNumberOfLines );
863 Length numberOfLines = 0u;
865 if( updateCurrentBuffer )
867 newGlyphPositions.Resize( layoutParameters.numberOfGlyphs );
868 glyphPositionsBuffer = newGlyphPositions.Begin();
870 newLines.Resize( linesCapacity );
871 linesBuffer = newLines.Begin();
875 glyphPositionsBuffer = glyphPositions.Begin();
877 lines.Resize( linesCapacity );
878 linesBuffer = lines.Begin();
881 float penY = CalculateLineOffset( lines,
882 layoutParameters.startLineIndex );
884 for( GlyphIndex index = layoutParameters.startGlyphIndex; index < lastGlyphPlusOne; )
886 CharacterDirection currentParagraphDirection = paragraphDirection;
888 // Get the layout for the line.
890 layout.glyphIndex = index;
891 GetLineLayoutForBox( layoutParameters,
896 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " glyph index %d\n", layout.glyphIndex );
897 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " character index %d\n", layout.characterIndex );
898 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " number of glyphs %d\n", layout.numberOfGlyphs );
899 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " number of characters %d\n", layout.numberOfCharacters );
900 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " length %f\n", layout.length );
902 if( 0u == layout.numberOfGlyphs )
904 // The width is too small and no characters are laid-out.
905 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--LayoutText width too small!\n\n" );
907 lines.Resize( numberOfLines );
911 // Set the line position. Discard if ellipsis is enabled and the position exceeds the boundaries
913 penY += layout.ascender;
915 DALI_LOG_INFO( gLogFilter, Debug::Verbose, " pen y %f\n", penY );
917 bool ellipsis = false;
918 if( elideTextEnabled )
920 // Does the ellipsis of the last line.
921 ellipsis = EllipsisLine( layoutParameters,
925 glyphPositionsBuffer,
928 currentParagraphDirection );
933 // No more lines to layout.
938 // Whether the last line has been laid-out.
939 const bool isLastLine = index + layout.numberOfGlyphs == layoutParameters.totalNumberOfGlyphs;
941 if( numberOfLines == linesCapacity )
943 // Reserve more space for the next lines.
944 linesBuffer = ResizeLinesBuffer( lines,
947 updateCurrentBuffer );
950 // Updates the current text's layout with the line's layout.
951 UpdateTextLayout( layoutParameters,
959 const GlyphIndex nextIndex = index + layout.numberOfGlyphs;
961 if( ( nextIndex == layoutParameters.totalNumberOfGlyphs ) &&
962 layoutParameters.isLastNewParagraph &&
963 ( mLayout == MULTI_LINE_BOX ) )
965 // The last character of the text is a new paragraph character.
966 // An extra line with no characters is added to increase the text's height
967 // in order to place the cursor.
969 if( numberOfLines == linesCapacity )
971 // Reserve more space for the next lines.
972 linesBuffer = ResizeLinesBuffer( lines,
975 updateCurrentBuffer );
978 UpdateTextLayout( layoutParameters,
979 layout.characterIndex + layout.numberOfCharacters,
980 index + layout.numberOfGlyphs,
984 } // whether to add a last line.
986 // Sets the positions of the glyphs.
987 SetGlyphPositions( layoutParameters.glyphsBuffer + index,
988 layout.numberOfGlyphs,
989 layoutParameters.outlineWidth,
990 glyphPositionsBuffer + index - layoutParameters.startGlyphIndex );
992 // Updates the vertical pen's position.
993 penY += -layout.descender + layout.lineSpacing + mDefaultLineSpacing;
995 // Increase the glyph index.
998 } // end for() traversing glyphs.
1000 if( updateCurrentBuffer )
1002 glyphPositions.Insert( glyphPositions.Begin() + layoutParameters.startGlyphIndex,
1003 newGlyphPositions.Begin(),
1004 newGlyphPositions.End() );
1005 glyphPositions.Resize( layoutParameters.totalNumberOfGlyphs );
1007 newLines.Resize( numberOfLines );
1009 // Current text's layout size adds only the newly laid-out lines.
1010 // Updates the layout size with the previously laid-out lines.
1011 UpdateLayoutSize( lines,
1014 if( 0u != newLines.Count() )
1016 const LineRun& lastLine = *( newLines.End() - 1u );
1018 const Length characterOffset = lastLine.characterRun.characterIndex + lastLine.characterRun.numberOfCharacters;
1019 const Length glyphOffset = lastLine.glyphRun.glyphIndex + lastLine.glyphRun.numberOfGlyphs;
1021 // Update the indices of the runs before the new laid-out lines are inserted.
1022 UpdateLineIndexOffsets( layoutParameters,
1027 // Insert the lines.
1028 lines.Insert( lines.Begin() + layoutParameters.startLineIndex,
1035 lines.Resize( numberOfLines );
1038 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "<--LayoutText\n\n" );
1043 void ReLayoutRightToLeftLines( const Parameters& layoutParameters,
1044 CharacterIndex startIndex,
1045 Length numberOfCharacters,
1046 Vector<Vector2>& glyphPositions )
1048 const CharacterIndex lastCharacterIndex = startIndex + numberOfCharacters;
1050 // Traverses the paragraphs with right to left characters.
1051 for( LineIndex lineIndex = 0u; lineIndex < layoutParameters.numberOfBidirectionalInfoRuns; ++lineIndex )
1053 const BidirectionalLineInfoRun& bidiLine = *( layoutParameters.lineBidirectionalInfoRunsBuffer + lineIndex );
1055 if( startIndex >= bidiLine.characterRun.characterIndex + bidiLine.characterRun.numberOfCharacters )
1057 // Do not reorder the line if it has been already reordered.
1061 if( bidiLine.characterRun.characterIndex >= lastCharacterIndex )
1063 // Do not reorder the lines after the last requested character.
1067 const CharacterIndex characterVisualIndex = bidiLine.characterRun.characterIndex + *bidiLine.visualToLogicalMap;
1068 const GlyphInfo& glyph = *( layoutParameters.glyphsBuffer + *( layoutParameters.charactersToGlyphsBuffer + characterVisualIndex ) );
1070 float penX = ( 0.f > glyph.xBearing ) ? -glyph.xBearing - layoutParameters.outlineWidth : -layoutParameters.outlineWidth;
1072 Vector2* glyphPositionsBuffer = glyphPositions.Begin();
1074 // Traverses the characters of the right to left paragraph.
1075 for( CharacterIndex characterLogicalIndex = 0u;
1076 characterLogicalIndex < bidiLine.characterRun.numberOfCharacters;
1077 ++characterLogicalIndex )
1079 // Convert the character in the logical order into the character in the visual order.
1080 const CharacterIndex characterVisualIndex = bidiLine.characterRun.characterIndex + *( bidiLine.visualToLogicalMap + characterLogicalIndex );
1082 // Get the number of glyphs of the character.
1083 const Length numberOfGlyphs = *( layoutParameters.glyphsPerCharacterBuffer + characterVisualIndex );
1085 for( GlyphIndex index = 0u; index < numberOfGlyphs; ++index )
1087 // Convert the character in the visual order into the glyph in the visual order.
1088 const GlyphIndex glyphIndex = *( layoutParameters.charactersToGlyphsBuffer + characterVisualIndex ) + index;
1090 DALI_ASSERT_DEBUG( 0u <= glyphIndex && glyphIndex < layoutParameters.totalNumberOfGlyphs );
1092 const GlyphInfo& glyph = *( layoutParameters.glyphsBuffer + glyphIndex );
1093 Vector2& position = *( glyphPositionsBuffer + glyphIndex );
1095 position.x = penX + glyph.xBearing;
1096 penX += glyph.advance;
1102 void Align( const Size& size,
1103 CharacterIndex startIndex,
1104 Length numberOfCharacters,
1105 Text::HorizontalAlignment::Type horizontalAlignment,
1106 Vector<LineRun>& lines,
1107 float& alignmentOffset,
1108 Dali::LayoutDirection::Type layoutDirection,
1109 bool matchSystemLanguageDirection )
1111 const CharacterIndex lastCharacterPlusOne = startIndex + numberOfCharacters;
1113 alignmentOffset = MAX_FLOAT;
1114 // Traverse all lines and align the glyphs.
1115 for( Vector<LineRun>::Iterator it = lines.Begin(), endIt = lines.End();
1119 LineRun& line = *it;
1121 if( line.characterRun.characterIndex < startIndex )
1123 // Do not align lines which have already been aligned.
1127 if( line.characterRun.characterIndex >= lastCharacterPlusOne )
1129 // Do not align lines beyond the last laid-out character.
1133 // Calculate the line's alignment offset accordingly with the align option,
1134 // the box width, line length, and the paragraph's direction.
1135 CalculateHorizontalAlignment( size.width,
1136 horizontalAlignment,
1139 matchSystemLanguageDirection );
1141 // Updates the alignment offset.
1142 alignmentOffset = std::min( alignmentOffset, line.alignmentOffset );
1146 void CalculateHorizontalAlignment( float boxWidth,
1147 HorizontalAlignment::Type horizontalAlignment,
1149 Dali::LayoutDirection::Type layoutDirection,
1150 bool matchSystemLanguageDirection )
1152 line.alignmentOffset = 0.f;
1153 bool isRTL = RTL == line.direction;
1154 float lineLength = line.width;
1155 HorizontalAlignment::Type alignment = horizontalAlignment;
1157 // match align for system language direction
1158 if( matchSystemLanguageDirection )
1160 isRTL = layoutDirection == LayoutDirection::RIGHT_TO_LEFT;
1163 // Swap the alignment type if the line is right to left.
1168 case HorizontalAlignment::BEGIN:
1170 alignment = HorizontalAlignment::END;
1173 case HorizontalAlignment::CENTER:
1178 case HorizontalAlignment::END:
1180 alignment = HorizontalAlignment::BEGIN;
1187 // Calculate the horizontal line offset.
1190 case HorizontalAlignment::BEGIN:
1192 line.alignmentOffset = 0.f;
1196 // 'Remove' the white spaces at the end of the line (which are at the beginning in visual order)
1197 line.alignmentOffset -= line.extraLength;
1201 case HorizontalAlignment::CENTER:
1203 line.alignmentOffset = 0.5f * ( boxWidth - lineLength );
1207 line.alignmentOffset -= line.extraLength;
1210 line.alignmentOffset = floorf( line.alignmentOffset ); // try to avoid pixel alignment.
1213 case HorizontalAlignment::END:
1217 lineLength += line.extraLength;
1220 line.alignmentOffset = boxWidth - lineLength;
1226 void Initialize( LineRun& line )
1228 line.glyphRun.glyphIndex = 0u;
1229 line.glyphRun.numberOfGlyphs = 0u;
1230 line.characterRun.characterIndex = 0u;
1231 line.characterRun.numberOfCharacters = 0u;
1233 line.ascender = 0.f;
1234 line.descender = 0.f;
1235 line.extraLength = 0.f;
1236 line.alignmentOffset = 0.f;
1237 line.direction = !RTL;
1238 line.ellipsis = false;
1239 line.lineSpacing = mDefaultLineSpacing;
1244 float mDefaultLineSpacing;
1245 float mPreviousCharacterExtraWidth;
1247 IntrusivePtr<Metrics> mMetrics;
1253 mImpl = new Engine::Impl();
1261 void Engine::SetMetrics( MetricsPtr& metrics )
1263 mImpl->mMetrics = metrics;
1266 void Engine::SetLayout( Type layout )
1268 mImpl->mLayout = layout;
1271 Engine::Type Engine::GetLayout() const
1273 DALI_LOG_INFO( gLogFilter, Debug::Verbose, "GetLayout[%d]\n", mImpl->mLayout);
1274 return mImpl->mLayout;
1277 void Engine::SetCursorWidth( int width )
1279 mImpl->mCursorWidth = static_cast<float>( width );
1282 int Engine::GetCursorWidth() const
1284 return static_cast<int>( mImpl->mCursorWidth );
1287 bool Engine::LayoutText( const Parameters& layoutParameters,
1288 Vector<Vector2>& glyphPositions,
1289 Vector<LineRun>& lines,
1291 bool elideTextEnabled )
1293 return mImpl->LayoutText( layoutParameters,
1300 void Engine::ReLayoutRightToLeftLines( const Parameters& layoutParameters,
1301 CharacterIndex startIndex,
1302 Length numberOfCharacters,
1303 Vector<Vector2>& glyphPositions )
1305 mImpl->ReLayoutRightToLeftLines( layoutParameters,
1311 void Engine::Align( const Size& size,
1312 CharacterIndex startIndex,
1313 Length numberOfCharacters,
1314 Text::HorizontalAlignment::Type horizontalAlignment,
1315 Vector<LineRun>& lines,
1316 float& alignmentOffset,
1317 Dali::LayoutDirection::Type layoutDirection,
1318 bool matchSystemLanguageDirection )
1323 horizontalAlignment,
1327 matchSystemLanguageDirection );
1330 void Engine::SetDefaultLineSpacing( float lineSpacing )
1332 mImpl->mDefaultLineSpacing = lineSpacing;
1335 float Engine::GetDefaultLineSpacing() const
1337 return mImpl->mDefaultLineSpacing;
1340 } // namespace Layout
1344 } // namespace Toolkit