dali-toolkit/internal/text/rendering/styles/strikethrough-helper-functions.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/rendering/styles/strikethrough-helper-functions.h>
  20
  21 namespace Dali
  22 {
  23 namespace Toolkit
  24 {
  25 namespace Text
  26 {
  27 bool IsGlyphStrikethrough(GlyphIndex                                    index,
  28                           const Vector<StrikethroughGlyphRun>&          strikethroughRuns,
  29                           Vector<StrikethroughGlyphRun>::ConstIterator& currentStrikethroughGlyphRunIt)
  30 {
  31   for(Vector<StrikethroughGlyphRun>::ConstIterator it    = strikethroughRuns.Begin(),
  32                                                    endIt = strikethroughRuns.End();
  33       it != endIt;
  34       ++it)
  35   {
  36     const StrikethroughGlyphRun& run = *it;
  37
  38     if((run.glyphRun.glyphIndex <= index) && (index < run.glyphRun.glyphIndex + run.glyphRun.numberOfGlyphs))
  39     {
  40       currentStrikethroughGlyphRunIt = it;
  41       return true;
  42     }
  43   }
  44
  45   return false;
  46 }
  47
  48 StrikethroughStyleProperties GetCurrentStrikethroughProperties(GlyphIndex                                    index,
  49                                                                const bool&                                   isGlyphStrikethrough,
  50                                                                const Vector<StrikethroughGlyphRun>&          strikethroughRuns,
  51                                                                Vector<StrikethroughGlyphRun>::ConstIterator& currentStrikethroughGlyphRunIt,
  52                                                                const StrikethroughStyleProperties&           commonStrikethroughProperties)
  53 {
  54   StrikethroughStyleProperties currentStrikethroughStyleProperties = commonStrikethroughProperties;
  55
  56   if(isGlyphStrikethrough && (currentStrikethroughGlyphRunIt != strikethroughRuns.End()))
  57   {
  58     // Retrieve the latest run to handle the nested case.
  59     for(Vector<StrikethroughGlyphRun>::ConstIterator it    = currentStrikethroughGlyphRunIt + 1,
  60                                                      endIt = strikethroughRuns.End();
  61         it != endIt;
  62         ++it)
  63     {
  64       const StrikethroughGlyphRun& run = *it;
  65
  66       if((run.glyphRun.glyphIndex <= index) && (index < (run.glyphRun.glyphIndex + run.glyphRun.numberOfGlyphs)))
  67       {
  68         currentStrikethroughGlyphRunIt = it;
  69       }
  70     }
  71
  72     currentStrikethroughStyleProperties.OverrideByDefinedProperties(currentStrikethroughGlyphRunIt->properties);
  73   }
  74
  75   return currentStrikethroughStyleProperties;
  76 }
  77
  78 /// Helper method to fetch the strikethrough metrics for the specified font glyph
  79 void CalcualteStrikethroughHeight(float& currentStrikethroughHeight, float& maxStrikethroughHeight)
  80 {
  81   //Height of strikethrough represents the thickness of line.
  82
  83   // Ensure strikethrough will be at least a pixel high
  84   if(currentStrikethroughHeight < 1.0f)
  85   {
  86     currentStrikethroughHeight = 1.0f;
  87   }
  88   else
  89   {
  90     currentStrikethroughHeight = ceil(currentStrikethroughHeight);
  91   }
  92
  93   // The strikethrough height should be the max strikethrough height of all glyphs of the line.
  94   if(currentStrikethroughHeight > maxStrikethroughHeight)
  95   {
  96     maxStrikethroughHeight = currentStrikethroughHeight;
  97   }
  98 }
  99
 100 } // namespace Text
 101
 102 } // namespace Toolkit
 103
 104 } // namespace Dali