[dali_2.3.43] Merge branch 'devel/master'
[platform/core/uifw/dali-toolkit.git] / dali-toolkit / internal / text / rendering / text-typesetter.cpp
index 9d58934..52747a3 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2024 Samsung Electronics Co., Ltd.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
 
 // EXTERNAL INCLUDES
 #include <dali/devel-api/text-abstraction/font-client.h>
+#include <dali/integration-api/debug.h>
+#include <dali/integration-api/trace.h>
 #include <dali/public-api/common/constants.h>
+#include <dali/public-api/math/math-utils.h>
 #include <memory.h>
+#include <cmath>
 
 // INTERNAL INCLUDES
 #include <dali-toolkit/devel-api/controls/text-controls/text-label-devel.h>
 #include <dali-toolkit/internal/text/glyph-metrics-helper.h>
+#include <dali-toolkit/internal/text/line-helper-functions.h>
+#include <dali-toolkit/internal/text/rendering/styles/character-spacing-helper-functions.h>
 #include <dali-toolkit/internal/text/rendering/styles/strikethrough-helper-functions.h>
 #include <dali-toolkit/internal/text/rendering/styles/underline-helper-functions.h>
+#include <dali-toolkit/internal/text/rendering/text-typesetter-impl.h>
 #include <dali-toolkit/internal/text/rendering/view-model.h>
 
 namespace Dali
@@ -38,523 +45,142 @@ namespace Text
 {
 namespace
 {
-const float HALF(0.5f);
-const float ONE_AND_A_HALF(1.5f);
-/**
- * @brief Data struct used to set the buffer of the glyph's bitmap into the final bitmap's buffer.
- */
-struct GlyphData
-{
-  Devel::PixelBuffer                           bitmapBuffer;     ///< The buffer of the whole bitmap. The format is RGBA8888.
-  Vector2*                                     position;         ///< The position of the glyph.
-  TextAbstraction::FontClient::GlyphBufferData glyphBitmap;      ///< The glyph's bitmap.
-  unsigned int                                 width;            ///< The bitmap's width.
-  unsigned int                                 height;           ///< The bitmap's height.
-  int                                          horizontalOffset; ///< The horizontal offset to be added to the 'x' glyph's position.
-  int                                          verticalOffset;   ///< The vertical offset to be added to the 'y' glyph's position.
-};
+DALI_INIT_TRACE_FILTER(gTraceFilter, DALI_TRACE_TEXT_PERFORMANCE_MARKER, false);
 
 /**
- * @brief Sets the glyph's buffer into the bitmap's buffer.
+ * @brief Fast multiply & divide by 255. It wiil be useful when we applying alpha value in color
  *
- * @param[in] data Struct which contains the glyph's data and the bitmap's data.
- * @param[in] position The position of the glyph.
- * @param[in] color The color of the glyph.
- * @param[in] style The style of the text.
- * @param[in] pixelFormat The format of the pixel in the image that the text is rendered as (i.e. either Pixel::BGRA8888 or Pixel::L8).
+ * @param x The value between [0..255]
+ * @param y The value between [0..255]
+ * @return (x*y)/255
  */
-void TypesetGlyph(GlyphData&           data,
-                  const Vector2* const position,
-                  const Vector4* const color,
-                  Typesetter::Style    style,
-                  Pixel::Format        pixelFormat)
+inline uint8_t MultiplyAndNormalizeColor(const uint8_t x, const uint8_t y) noexcept
 {
-  if((0u == data.glyphBitmap.width) || (0u == data.glyphBitmap.height))
-  {
-    // Nothing to do if the width or height of the buffer is zero.
-    return;
-  }
-
-  const int widthMinusOne  = static_cast<int>(data.width - 1u);
-  const int heightMinusOne = static_cast<int>(data.height - 1u);
-
-  if(Pixel::RGBA8888 == pixelFormat)
-  {
-    // Whether the given glyph is a color one.
-    const bool     isColorGlyph   = data.glyphBitmap.isColorEmoji || data.glyphBitmap.isColorBitmap;
-    const uint32_t glyphPixelSize = Pixel::GetBytesPerPixel(data.glyphBitmap.format);
-    const uint32_t alphaIndex     = glyphPixelSize - 1u;
-    const bool     swapChannelsBR = Pixel::BGRA8888 == data.glyphBitmap.format;
-
-    // Pointer to the color glyph if there is one.
-    const uint32_t* const colorGlyphBuffer = isColorGlyph ? reinterpret_cast<uint32_t*>(data.glyphBitmap.buffer) : NULL;
-
-    // Initial vertical offset.
-    const int yOffset = data.verticalOffset + position->y;
-
-    uint32_t* bitmapBuffer = reinterpret_cast<uint32_t*>(data.bitmapBuffer.GetBuffer());
-
-    // Traverse the pixels of the glyph line per line.
-    for(int lineIndex = 0, glyphHeight = static_cast<int>(data.glyphBitmap.height); lineIndex < glyphHeight; ++lineIndex)
-    {
-      const int yOffsetIndex = yOffset + lineIndex;
-      if((0 > yOffsetIndex) || (yOffsetIndex > heightMinusOne))
-      {
-        // Do not write out of bounds.
-        continue;
-      }
-
-      const int verticalOffset    = yOffsetIndex * data.width;
-      const int xOffset           = data.horizontalOffset + position->x;
-      const int glyphBufferOffset = lineIndex * static_cast<int>(data.glyphBitmap.width);
-      for(int index = 0, glyphWidth = static_cast<int>(data.glyphBitmap.width); index < glyphWidth; ++index)
-      {
-        const int xOffsetIndex = xOffset + index;
-        if((0 > xOffsetIndex) || (xOffsetIndex > widthMinusOne))
-        {
-          // Don't write out of bounds.
-          continue;
-        }
-
-        if(isColorGlyph)
-        {
-          // Retrieves the color from the color glyph.
-          uint32_t packedColorGlyph       = *(colorGlyphBuffer + glyphBufferOffset + index);
-          uint8_t* packedColorGlyphBuffer = reinterpret_cast<uint8_t*>(&packedColorGlyph);
-
-          // Update the alpha channel.
-          if(Typesetter::STYLE_MASK == style || Typesetter::STYLE_OUTLINE == style) // Outline not shown for color glyph
-          {
-            // Create an alpha mask for color glyph.
-            *(packedColorGlyphBuffer + 3u) = 0u;
-            *(packedColorGlyphBuffer + 2u) = 0u;
-            *(packedColorGlyphBuffer + 1u) = 0u;
-            *packedColorGlyphBuffer        = 0u;
-          }
-          else
-          {
-            const uint8_t colorAlpha       = static_cast<uint8_t>(color->a * static_cast<float>(*(packedColorGlyphBuffer + 3u)));
-            *(packedColorGlyphBuffer + 3u) = colorAlpha;
-
-            if(Typesetter::STYLE_SHADOW == style)
-            {
-              // The shadow of color glyph needs to have the shadow color.
-              *(packedColorGlyphBuffer + 2u) = static_cast<uint8_t>(color->b * colorAlpha);
-              *(packedColorGlyphBuffer + 1u) = static_cast<uint8_t>(color->g * colorAlpha);
-              *packedColorGlyphBuffer        = static_cast<uint8_t>(color->r * colorAlpha);
-            }
-            else
-            {
-              if(swapChannelsBR)
-              {
-                std::swap(*packedColorGlyphBuffer, *(packedColorGlyphBuffer + 2u)); // Swap B and R.
-              }
-
-              *(packedColorGlyphBuffer + 2u) = (*(packedColorGlyphBuffer + 2u) * colorAlpha / 255);
-              *(packedColorGlyphBuffer + 1u) = (*(packedColorGlyphBuffer + 1u) * colorAlpha / 255);
-              *packedColorGlyphBuffer        = (*(packedColorGlyphBuffer)*colorAlpha / 255);
-
-              if(data.glyphBitmap.isColorBitmap)
-              {
-                *(packedColorGlyphBuffer + 2u) = static_cast<uint8_t>(*(packedColorGlyphBuffer + 2u) * color->b);
-                *(packedColorGlyphBuffer + 1u) = static_cast<uint8_t>(*(packedColorGlyphBuffer + 1u) * color->g);
-                *packedColorGlyphBuffer        = static_cast<uint8_t>(*packedColorGlyphBuffer * color->r);
-              }
-            }
-          }
-
-          // Set the color into the final pixel buffer.
-          *(bitmapBuffer + verticalOffset + xOffsetIndex) = packedColorGlyph;
-        }
-        else
-        {
-          // Pack the given color into a 32bit buffer. The alpha channel will be updated later for each pixel.
-          // The format is RGBA8888.
-          uint32_t packedColor       = 0u;
-          uint8_t* packedColorBuffer = reinterpret_cast<uint8_t*>(&packedColor);
-
-          // Update the alpha channel.
-          const uint8_t alpha = *(data.glyphBitmap.buffer + glyphPixelSize * (glyphBufferOffset + index) + alphaIndex);
-
-          // Copy non-transparent pixels only
-          if(alpha > 0u)
-          {
-            // Check alpha of overlapped pixels
-            uint32_t& currentColor             = *(bitmapBuffer + verticalOffset + xOffsetIndex);
-            uint8_t*  packedCurrentColorBuffer = reinterpret_cast<uint8_t*>(&currentColor);
-
-            // For any pixel overlapped with the pixel in previous glyphs, make sure we don't
-            // overwrite a previous bigger alpha with a smaller alpha (in order to avoid
-            // semi-transparent gaps between joint glyphs with overlapped pixels, which could
-            // happen, for example, in the RTL text when we copy glyphs from right to left).
-            uint8_t currentAlpha = *(packedCurrentColorBuffer + 3u);
-            currentAlpha         = std::max(currentAlpha, alpha);
-
-            // Color is pre-muliplied with its alpha.
-            *(packedColorBuffer + 3u) = static_cast<uint8_t>(color->a * currentAlpha);
-            *(packedColorBuffer + 2u) = static_cast<uint8_t>(color->b * currentAlpha);
-            *(packedColorBuffer + 1u) = static_cast<uint8_t>(color->g * currentAlpha);
-            *(packedColorBuffer)      = static_cast<uint8_t>(color->r * currentAlpha);
-
-            // Set the color into the final pixel buffer.
-            currentColor = packedColor;
-          }
-        }
-      }
-    }
-  }
-  else
-  {
-    // Whether the given glyph is a color one.
-    const bool     isColorGlyph   = data.glyphBitmap.isColorEmoji || data.glyphBitmap.isColorBitmap;
-    const uint32_t glyphPixelSize = Pixel::GetBytesPerPixel(data.glyphBitmap.format);
-    const uint32_t alphaIndex     = glyphPixelSize - 1u;
-
-    // Initial vertical offset.
-    const int yOffset = data.verticalOffset + position->y;
-
-    uint8_t* bitmapBuffer = reinterpret_cast<uint8_t*>(data.bitmapBuffer.GetBuffer());
-
-    // Traverse the pixels of the glyph line per line.
-    for(int lineIndex = 0, glyphHeight = static_cast<int>(data.glyphBitmap.height); lineIndex < glyphHeight; ++lineIndex)
-    {
-      const int yOffsetIndex = yOffset + lineIndex;
-      if((0 > yOffsetIndex) || (yOffsetIndex > heightMinusOne))
-      {
-        // Do not write out of bounds.
-        continue;
-      }
-
-      const int verticalOffset    = yOffsetIndex * data.width;
-      const int xOffset           = data.horizontalOffset + position->x;
-      const int glyphBufferOffset = lineIndex * static_cast<int>(data.glyphBitmap.width);
-      for(int index = 0, glyphWidth = static_cast<int>(data.glyphBitmap.width); index < glyphWidth; ++index)
-      {
-        const int xOffsetIndex = xOffset + index;
-        if((0 > xOffsetIndex) || (xOffsetIndex > widthMinusOne))
-        {
-          // Don't write out of bounds.
-          continue;
-        }
-
-        if(!isColorGlyph)
-        {
-          // Update the alpha channel.
-          const uint8_t alpha = *(data.glyphBitmap.buffer + glyphPixelSize * (glyphBufferOffset + index) + alphaIndex);
-
-          // Copy non-transparent pixels only
-          if(alpha > 0u)
-          {
-            // Check alpha of overlapped pixels
-            uint8_t& currentAlpha = *(bitmapBuffer + verticalOffset + xOffsetIndex);
-
-            // For any pixel overlapped with the pixel in previous glyphs, make sure we don't
-            // overwrite a previous bigger alpha with a smaller alpha (in order to avoid
-            // semi-transparent gaps between joint glyphs with overlapped pixels, which could
-            // happen, for example, in the RTL text when we copy glyphs from right to left).
-            currentAlpha = std::max(currentAlpha, alpha);
-          }
-        }
-      }
-    }
-  }
+  const uint32_t xy = static_cast<const uint32_t>(x) * y;
+  return ((xy << 15) + (xy << 7) + xy) >> 23;
 }
 
-/// Draws the specified color to the pixel buffer
-void WriteColorToPixelBuffer(
-  GlyphData&         glyphData,
-  uint32_t*          bitmapBuffer,
-  const Vector4&     color,
-  const unsigned int x,
-  const unsigned int y)
+/**
+ * @brief Fast multiply & Summation & divide by 255.
+ *
+ * @param x1 The value between [0..255]
+ * @param y1 The value between [0..255]
+ * @param x2 The value between [0..255]
+ * @param y2 The value between [0..255]
+ * @return min(255, (x1*y1)/255 + (x2*y2)/255)
+ */
+inline uint8_t MultiplyAndSummationAndNormalizeColor(const uint8_t x1, const uint8_t y1, const uint8_t x2, const uint8_t y2) noexcept
 {
-  // Always RGBA image for text with styles
-  uint32_t pixel       = *(bitmapBuffer + y * glyphData.width + x);
-  uint8_t* pixelBuffer = reinterpret_cast<uint8_t*>(&pixel);
-
-  // Write the color to the pixel buffer
-  uint8_t colorAlpha  = static_cast<uint8_t>(color.a * 255.f);
-  *(pixelBuffer + 3u) = colorAlpha;
-  *(pixelBuffer + 2u) = static_cast<uint8_t>(color.b * colorAlpha);
-  *(pixelBuffer + 1u) = static_cast<uint8_t>(color.g * colorAlpha);
-  *(pixelBuffer)      = static_cast<uint8_t>(color.r * colorAlpha);
-
-  *(bitmapBuffer + y * glyphData.width + x) = pixel;
+  const uint32_t xy1 = static_cast<const uint32_t>(x1) * y1;
+  const uint32_t xy2 = static_cast<const uint32_t>(x2) * y2;
+  const uint32_t res = std::min(65025u, xy1 + xy2); // 65025 is 255 * 255.
+  return ((res + ((res + 257) >> 8)) >> 8);         // fast divide by 255.
 }
 
-/// Draws the specified underline color to the buffer
-void DrawUnderline(
-  const unsigned int              bufferWidth,
-  const unsigned int              bufferHeight,
-  GlyphData&                      glyphData,
-  const float                     baseline,
-  const float                     currentUnderlinePosition,
-  const float                     maxUnderlineHeight,
-  const float                     lineExtentLeft,
-  const float                     lineExtentRight,
-  const UnderlineStyleProperties& commonUnderlineProperties,
-  const UnderlineStyleProperties& currentUnderlineProperties,
-  const LineRun&                  line)
+/**
+ * @brief Combine the two RGBA image buffers together.
+ *
+ * The top layer buffer will blend over the bottom layer buffer:
+ * - If the pixel is not fully opaque from either buffer, it will be blended with
+ *   the pixel from the other buffer and copied to the combined buffer.
+ * - If the pixels from both buffers are fully opaque, the pixels from the top layer
+ *   buffer will be copied to the combined buffer.
+ *
+ * Due to the performance issue, We need to re-use input'ed pixelBuffer memory.
+ * We can determine which pixelBuffer's memory is destination
+ *
+ * @param[in, out] topPixelBuffer The top layer buffer.
+ * @param[in, out] bottomPixelBuffer The bottom layer buffer.
+ * @param[in] bufferWidth The width of the image buffer.
+ * @param[in] bufferHeight The height of the image buffer.
+ * @param[in] storeResultIntoTop True if we store the combined image buffer result into topPixelBuffer.
+ * False if we store the combined image buffer result into bottomPixelBuffer.
+ *
+ */
+void CombineImageBuffer(Devel::PixelBuffer& __restrict__ topPixelBuffer, Devel::PixelBuffer& __restrict__ bottomPixelBuffer, const uint32_t bufferWidth, const uint32_t bufferHeight, bool storeResultIntoTop)
 {
-  const Vector4&              underlineColor       = currentUnderlineProperties.colorDefined ? currentUnderlineProperties.color : commonUnderlineProperties.color;
-  const Text::Underline::Type underlineType        = currentUnderlineProperties.typeDefined ? currentUnderlineProperties.type : commonUnderlineProperties.type;
-  const float                 dashedUnderlineWidth = currentUnderlineProperties.dashWidthDefined ? currentUnderlineProperties.dashWidth : commonUnderlineProperties.dashWidth;
-  const float                 dashedUnderlineGap   = currentUnderlineProperties.dashGapDefined ? currentUnderlineProperties.dashGap : commonUnderlineProperties.dashGap;
-
-  int       underlineYOffset = glyphData.verticalOffset + baseline + currentUnderlinePosition;
-  uint32_t* bitmapBuffer     = reinterpret_cast<uint32_t*>(glyphData.bitmapBuffer.GetBuffer());
+  // Assume that we always combine two RGBA images
+  // Jump with 4bytes for optimize runtime.
+  uint32_t* topBuffer    = reinterpret_cast<uint32_t*>(topPixelBuffer.GetBuffer());
+  uint32_t* bottomBuffer = reinterpret_cast<uint32_t*>(bottomPixelBuffer.GetBuffer());
 
-  for(unsigned int y = underlineYOffset; y < underlineYOffset + maxUnderlineHeight; y++)
+  if(topBuffer == nullptr && bottomBuffer == nullptr)
   {
-    if(y > bufferHeight - 1)
-    {
-      // Do not write out of bounds.
-      break;
-    }
-    if(underlineType == Text::Underline::DASHED)
-    {
-      float dashWidth = dashedUnderlineWidth;
-      float dashGap   = 0;
-
-      for(unsigned int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++)
-      {
-        if(x > bufferWidth - 1)
-        {
-          // Do not write out of bounds.
-          break;
-        }
-        if(dashGap == 0 && dashWidth > 0)
-        {
-          WriteColorToPixelBuffer(glyphData, bitmapBuffer, underlineColor, x, y);
-          dashWidth--;
-        }
-        else if(dashGap < dashedUnderlineGap)
-        {
-          dashGap++;
-        }
-        else
-        {
-          //reset
-          dashWidth = dashedUnderlineWidth;
-          dashGap   = 0;
-        }
-      }
-    }
-    else
-    {
-      for(unsigned int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++)
-      {
-        if(x > bufferWidth - 1)
-        {
-          // Do not write out of bounds.
-          break;
-        }
-        WriteColorToPixelBuffer(glyphData, bitmapBuffer, underlineColor, x, y);
-      }
-    }
+    // Nothing to do if both buffers are empty.
+    return;
   }
-  if(underlineType == Text::Underline::DOUBLE)
+
+  if(topBuffer == nullptr)
   {
-    int secondUnderlineYOffset = underlineYOffset - ONE_AND_A_HALF * maxUnderlineHeight;
-    for(unsigned int y = secondUnderlineYOffset; y < secondUnderlineYOffset + maxUnderlineHeight; y++)
+    // Nothing to do if topBuffer is empty.
+    // If we need to store the result into top, change topPixelBuffer as bottomPixelBuffer.
+    if(storeResultIntoTop)
     {
-      if(y > bufferHeight - 1)
-      {
-        // Do not write out of bounds.
-        break;
-      }
-      for(unsigned int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++)
-      {
-        if(x > bufferWidth - 1)
-        {
-          // Do not write out of bounds.
-          break;
-        }
-        WriteColorToPixelBuffer(glyphData, bitmapBuffer, underlineColor, x, y);
-      }
+      topPixelBuffer = bottomPixelBuffer;
     }
+    return;
   }
-}
 
-/// Draws the background color to the buffer
-void DrawBackgroundColor(
-  Vector4            backgroundColor,
-  const unsigned int bufferWidth,
-  const unsigned int bufferHeight,
-  GlyphData&         glyphData,
-  const float        baseline,
-  const LineRun&     line,
-  const float        lineExtentLeft,
-  const float        lineExtentRight)
-{
-  uint32_t* bitmapBuffer = reinterpret_cast<uint32_t*>(glyphData.bitmapBuffer.GetBuffer());
-
-  for(int y = glyphData.verticalOffset + baseline - line.ascender; y < glyphData.verticalOffset + baseline - line.descender; y++)
+  if(bottomBuffer == nullptr)
   {
-    if((y < 0) || (y > static_cast<int>(bufferHeight - 1)))
-    {
-      // Do not write out of bounds.
-      continue;
-    }
-
-    for(int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++)
+    // Nothing to do if bottomBuffer is empty.
+    // If we need to store the result into bottom, change bottomPixelBuffer as topPixelBuffer.
+    if(!storeResultIntoTop)
     {
-      if((x < 0) || (x > static_cast<int>(bufferWidth - 1)))
-      {
-        // Do not write out of bounds.
-        continue;
-      }
-
-      WriteColorToPixelBuffer(glyphData, bitmapBuffer, backgroundColor, x, y);
+      bottomPixelBuffer = topPixelBuffer;
     }
+    return;
   }
-}
-
-Devel::PixelBuffer DrawGlyphsBackground(const ViewModel* model, Devel::PixelBuffer& buffer, const unsigned int bufferWidth, const unsigned int bufferHeight, bool ignoreHorizontalAlignment, int horizontalOffset, int verticalOffset)
-{
-  // Retrieve lines, glyphs, positions and colors from the view model.
-  const Length            modelNumberOfLines           = model->GetNumberOfLines();
-  const LineRun* const    modelLinesBuffer             = model->GetLines();
-  const Length            numberOfGlyphs               = model->GetNumberOfGlyphs();
-  const GlyphInfo* const  glyphsBuffer                 = model->GetGlyphs();
-  const Vector2* const    positionBuffer               = model->GetLayout();
-  const Vector4* const    backgroundColorsBuffer       = model->GetBackgroundColors();
-  const ColorIndex* const backgroundColorIndicesBuffer = model->GetBackgroundColorIndices();
-
-  // Create and initialize the pixel buffer.
-  GlyphData glyphData;
-  glyphData.verticalOffset   = verticalOffset;
-  glyphData.width            = bufferWidth;
-  glyphData.height           = bufferHeight;
-  glyphData.bitmapBuffer     = buffer;
-  glyphData.horizontalOffset = 0;
-
-  ColorIndex prevBackgroundColorIndex = 0;
-  ColorIndex backgroundColorIndex     = 0;
-
-  // Traverses the lines of the text.
-  for(LineIndex lineIndex = 0u; lineIndex < modelNumberOfLines; ++lineIndex)
-  {
-    const LineRun& line = *(modelLinesBuffer + lineIndex);
 
-    // Sets the horizontal offset of the line.
-    glyphData.horizontalOffset = ignoreHorizontalAlignment ? 0 : static_cast<int>(line.alignmentOffset);
-    glyphData.horizontalOffset += horizontalOffset;
+  const uint32_t bufferSizeInt = bufferWidth * bufferHeight;
 
-    // Increases the vertical offset with the line's ascender.
-    glyphData.verticalOffset += static_cast<int>(line.ascender);
+  uint32_t* __restrict__ combinedBuffer       = storeResultIntoTop ? topBuffer : bottomBuffer;
+  uint8_t* __restrict__ topAlphaBufferPointer = reinterpret_cast<uint8_t*>(topBuffer) + 3;
 
-    // Include line spacing after first line
-    if(lineIndex > 0u)
-    {
-      glyphData.verticalOffset += static_cast<int>(line.lineSpacing);
-    }
+  for(uint32_t pixelIndex = 0; pixelIndex < bufferSizeInt; ++pixelIndex)
+  {
+    // If the alpha of the pixel in either buffer is not fully opaque, blend the two pixels.
+    // Otherwise, copy pixel from topBuffer to combinedBuffer.
+    // Note : Be careful when we read & write into combinedBuffer. It can be write into same pointer.
 
-    float left     = bufferWidth;
-    float right    = 0.0f;
-    float baseline = 0.0f;
+    uint8_t topAlpha = *topAlphaBufferPointer;
 
-    // Traverses the glyphs of the line.
-    const GlyphIndex endGlyphIndex = std::min(numberOfGlyphs, line.glyphRun.glyphIndex + line.glyphRun.numberOfGlyphs);
-    for(GlyphIndex glyphIndex = line.glyphRun.glyphIndex; glyphIndex < endGlyphIndex; ++glyphIndex)
+    if(topAlpha == 0)
     {
-      // Retrieve the glyph's info.
-      const GlyphInfo* const glyphInfo = glyphsBuffer + glyphIndex;
-
-      if((glyphInfo->width < Math::MACHINE_EPSILON_1000) ||
-         (glyphInfo->height < Math::MACHINE_EPSILON_1000))
+      // Copy the pixel from bottomBuffer to combinedBuffer
+      if(storeResultIntoTop)
       {
-        // Nothing to do if default background color, the glyph's width or height is zero.
-        continue;
+        *(combinedBuffer) = *(bottomBuffer);
       }
-
-      backgroundColorIndex = (nullptr == backgroundColorsBuffer) ? 0u : *(backgroundColorIndicesBuffer + glyphIndex);
-
-      if((backgroundColorIndex != prevBackgroundColorIndex) &&
-         (prevBackgroundColorIndex != 0u))
-      {
-        const Vector4& backgroundColor = *(backgroundColorsBuffer + prevBackgroundColorIndex - 1u);
-        DrawBackgroundColor(backgroundColor, bufferWidth, bufferHeight, glyphData, baseline, line, left, right);
-      }
-
-      if(backgroundColorIndex == 0u)
-      {
-        prevBackgroundColorIndex = backgroundColorIndex;
-        //if background color is the default do nothing
-        continue;
-      }
-
-      // Retrieves the glyph's position.
-      const Vector2* const position = positionBuffer + glyphIndex;
-
-      if(baseline < position->y + glyphInfo->yBearing)
-      {
-        baseline = position->y + glyphInfo->yBearing;
-      }
-
-      // Calculate the positions of leftmost and rightmost glyphs in the current line
-      if((position->x < left) || (backgroundColorIndex != prevBackgroundColorIndex))
-      {
-        left = position->x - glyphInfo->xBearing;
-      }
-
-      if(position->x + glyphInfo->width > right)
+    }
+    else if(topAlpha == 255)
+    {
+      // Copy the pixel from topBuffer to combinedBuffer
+      if(!storeResultIntoTop)
       {
-        right = position->x - glyphInfo->xBearing + glyphInfo->advance;
+        *(combinedBuffer) = *(topBuffer);
       }
-
-      prevBackgroundColorIndex = backgroundColorIndex;
     }
-
-    //draw last background at line end if not default
-    if(backgroundColorIndex != 0u)
+    else
     {
-      const Vector4& backgroundColor = *(backgroundColorsBuffer + backgroundColorIndex - 1u);
-      DrawBackgroundColor(backgroundColor, bufferWidth, bufferHeight, glyphData, baseline, line, left, right);
-    }
-
-    // Increases the vertical offset with the line's descender.
-    glyphData.verticalOffset += static_cast<int>(-line.descender);
-  }
-
-  return glyphData.bitmapBuffer;
-}
-
-/// Draws the specified strikethrough color to the buffer
-void DrawStrikethrough(const unsigned int                  bufferWidth,
-                       const unsigned int                  bufferHeight,
-                       GlyphData&                          glyphData,
-                       const float                         baseline,
-                       const float                         strikethroughStartingYPosition,
-                       const float                         maxStrikethroughHeight,
-                       const float                         lineExtentLeft,
-                       const float                         lineExtentRight,
-                       const StrikethroughStyleProperties& commonStrikethroughProperties,
-                       const StrikethroughStyleProperties& currentStrikethroughProperties,
-                       const LineRun&                      line)
-{
-  const Vector4& strikethroughColor = currentStrikethroughProperties.colorDefined ? currentStrikethroughProperties.color : commonStrikethroughProperties.color;
+      // At least one pixel is not fully opaque
+      // "Over" blend the the pixel from topBuffer with the pixel in bottomBuffer
+      uint32_t blendedBottomBufferColor                    = *(bottomBuffer);
+      uint8_t* __restrict__ blendedBottomBufferColorBuffer = reinterpret_cast<uint8_t*>(&blendedBottomBufferColor);
 
-  uint32_t* bitmapBuffer = reinterpret_cast<uint32_t*>(glyphData.bitmapBuffer.GetBuffer());
+      blendedBottomBufferColorBuffer[0] = MultiplyAndNormalizeColor(blendedBottomBufferColorBuffer[0], 255 - topAlpha);
+      blendedBottomBufferColorBuffer[1] = MultiplyAndNormalizeColor(blendedBottomBufferColorBuffer[1], 255 - topAlpha);
+      blendedBottomBufferColorBuffer[2] = MultiplyAndNormalizeColor(blendedBottomBufferColorBuffer[2], 255 - topAlpha);
+      blendedBottomBufferColorBuffer[3] = MultiplyAndNormalizeColor(blendedBottomBufferColorBuffer[3], 255 - topAlpha);
 
-  for(unsigned int y = strikethroughStartingYPosition; y < strikethroughStartingYPosition + maxStrikethroughHeight; y++)
-  {
-    if(y > bufferHeight - 1)
-    {
-      // Do not write out of bounds.
-      break;
+      *(combinedBuffer) = *(topBuffer) + blendedBottomBufferColor;
     }
 
-    for(unsigned int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++)
-    {
-      if(x > bufferWidth - 1)
-      {
-        // Do not write out of bounds.
-        break;
-      }
-
-      WriteColorToPixelBuffer(glyphData, bitmapBuffer, strikethroughColor, x, y);
-    }
+    // Increase each buffer's pointer.
+    ++combinedBuffer;
+    ++topBuffer;
+    ++bottomBuffer;
+    topAlphaBufferPointer += sizeof(uint32_t) / sizeof(uint8_t);
   }
 }
 
@@ -567,43 +193,50 @@ TypesetterPtr Typesetter::New(const ModelInterface* const model)
 
 ViewModel* Typesetter::GetViewModel()
 {
-  return mModel;
+  return mImpl->GetViewModel();
 }
 
-Devel::PixelBuffer Typesetter::CreateImageBuffer(const unsigned int bufferWidth, const unsigned int bufferHeight, Pixel::Format pixelFormat)
+void Typesetter::SetFontClient(TextAbstraction::FontClient& fontClient)
 {
-  Devel::PixelBuffer imageBuffer = Devel::PixelBuffer::New(bufferWidth, bufferHeight, pixelFormat);
+  mImpl->SetFontClient(fontClient);
+}
 
-  if(Pixel::RGBA8888 == pixelFormat)
-  {
-    const unsigned int bufferSizeInt  = bufferWidth * bufferHeight;
-    const unsigned int bufferSizeChar = 4u * bufferSizeInt;
-    memset(imageBuffer.GetBuffer(), 0u, bufferSizeChar);
-  }
-  else
-  {
-    memset(imageBuffer.GetBuffer(), 0, bufferWidth * bufferHeight);
-  }
+PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirection::Type textDirection, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat)
+{
+  Devel::PixelBuffer result    = RenderWithPixelBuffer(size, textDirection, behaviour, ignoreHorizontalAlignment, pixelFormat);
+  PixelData          pixelData = Devel::PixelBuffer::Convert(result);
 
-  return imageBuffer;
+  return pixelData;
 }
 
-PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirection::Type textDirection, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat)
+PixelData Typesetter::RenderWithCutout(const Vector2& size, Toolkit::DevelText::TextDirection::Type textDirection, Devel::PixelBuffer mask, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, float originAlpha)
+{
+  Devel::PixelBuffer result = RenderWithPixelBuffer(size, textDirection, behaviour, ignoreHorizontalAlignment, pixelFormat);
+  SetMaskForImageBuffer(mask, result, size.width, size.height, originAlpha);
+
+  PixelData pixelData = Devel::PixelBuffer::Convert(result);
+
+  return pixelData;
+}
+
+Devel::PixelBuffer Typesetter::RenderWithPixelBuffer(const Vector2& size, Toolkit::DevelText::TextDirection::Type textDirection, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat)
 {
+  DALI_TRACE_SCOPE(gTraceFilter, "DALI_TEXT_RENDERING_TYPESETTER");
   // @todo. This initial implementation for a TextLabel has only one visible page.
 
+  // Use l-value to make ensure it is not nullptr, so compiler happy.
+  auto& viewModel = *(mImpl->GetViewModel());
+
   // Elides the text if needed.
-  mModel->ElideGlyphs();
+  viewModel.ElideGlyphs(mImpl->GetFontClient());
 
   // Retrieves the layout size.
-  const Size& layoutSize = mModel->GetLayoutSize();
-
-  const int outlineWidth = static_cast<int>(mModel->GetOutlineWidth());
+  const Size&   layoutSize   = viewModel.GetLayoutSize();
+  const int32_t outlineWidth = static_cast<int32_t>(viewModel.GetOutlineWidth());
 
   // Set the offset for the horizontal alignment according to the text direction and outline width.
-  int penX = 0;
-
-  switch(mModel->GetHorizontalAlignment())
+  int32_t penX = 0;
+  switch(viewModel.GetHorizontalAlignment())
   {
     case HorizontalAlignment::BEGIN:
     {
@@ -623,9 +256,8 @@ PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirect
   }
 
   // Set the offset for the vertical alignment.
-  int penY = 0u;
-
-  switch(mModel->GetVerticalAlignment())
+  int32_t penY = 0u;
+  switch(viewModel.GetVerticalAlignment())
   {
     case VerticalAlignment::TOP:
     {
@@ -634,38 +266,24 @@ PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirect
     }
     case VerticalAlignment::CENTER:
     {
-      penY = static_cast<int>(0.5f * (size.height - layoutSize.height));
+      penY = static_cast<int32_t>(std::round(0.5f * (size.height - layoutSize.height)));
       penY = penY < 0.f ? 0.f : penY;
+
       break;
     }
     case VerticalAlignment::BOTTOM:
     {
-      penY = static_cast<int>(size.height - layoutSize.height);
+      penY = static_cast<int32_t>(size.height - layoutSize.height);
       break;
     }
   }
 
-  // Calculate vertical line alignment
-  switch(mModel->GetVerticalLineAlignment())
+  const bool isCutoutEnabled = viewModel.IsCutoutEnabled();
+  if(isCutoutEnabled)
   {
-    case DevelText::VerticalLineAlignment::TOP:
-    {
-      break;
-    }
-    case DevelText::VerticalLineAlignment::MIDDLE:
-    {
-      const auto& line = *mModel->GetLines();
-      penY -= line.descender;
-      penY += static_cast<int>(line.lineSpacing * 0.5f + line.descender);
-      break;
-    }
-    case DevelText::VerticalLineAlignment::BOTTOM:
-    {
-      const auto& line       = *mModel->GetLines();
-      const auto  lineHeight = line.ascender + (-line.descender) + line.lineSpacing;
-      penY += static_cast<int>(lineHeight - (line.ascender - line.descender));
-      break;
-    }
+    Vector2 offset = viewModel.GetOffsetWithCutout();
+    penX           = offset.x;
+    penY           = offset.y;
   }
 
   // Generate the image buffers of the text for each different style first,
@@ -673,22 +291,22 @@ PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirect
   // do all of these in CPU only, so that once the final texture is generated,
   // no calculation is needed in GPU during each frame.
 
-  const unsigned int bufferWidth  = static_cast<unsigned int>(size.width);
-  const unsigned int bufferHeight = static_cast<unsigned int>(size.height);
+  const uint32_t bufferWidth  = static_cast<uint32_t>(size.width);
+  const uint32_t bufferHeight = static_cast<uint32_t>(size.height);
 
-  const unsigned int bufferSizeInt  = bufferWidth * bufferHeight;
-  const unsigned int bufferSizeChar = 4u * bufferSizeInt;
+  const uint32_t bufferSizeInt  = bufferWidth * bufferHeight;
+  const size_t   bufferSizeChar = sizeof(uint32_t) * static_cast<std::size_t>(bufferSizeInt);
 
   //Elided text in ellipsis at START could start on index greater than 0
-  auto startIndexOfGlyphs = mModel->GetStartIndexOfElidedGlyphs();
-  auto endIndexOfGlyphs   = mModel->GetEndIndexOfElidedGlyphs();
+  auto startIndexOfGlyphs = viewModel.GetStartIndexOfElidedGlyphs();
+  auto endIndexOfGlyphs   = viewModel.GetEndIndexOfElidedGlyphs();
 
   Devel::PixelBuffer imageBuffer;
 
   if(RENDER_MASK == behaviour)
   {
     // Generate the image buffer as an alpha mask for color glyphs.
-    imageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_MASK, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+    imageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_MASK, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
   }
   else if(RENDER_NO_TEXT == behaviour || RENDER_OVERLAY_STYLE == behaviour)
   {
@@ -699,33 +317,42 @@ PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirect
   else
   {
     // Generate the image buffer for the text with no style.
-    imageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_NONE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+    imageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_NONE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
   }
 
   if((RENDER_NO_STYLES != behaviour) && (RENDER_MASK != behaviour))
   {
     // Generate the outline if enabled
-    const uint16_t outlineWidth = mModel->GetOutlineWidth();
-    if(outlineWidth != 0u && RENDER_OVERLAY_STYLE != behaviour)
+    const uint16_t outlineWidth = viewModel.GetOutlineWidth();
+    const float    outlineAlpha = viewModel.GetOutlineColor().a;
+    if(outlineWidth != 0u && fabsf(outlineAlpha) > Math::MACHINE_EPSILON_1 && RENDER_OVERLAY_STYLE != behaviour)
     {
       // Create the image buffer for outline
-      Devel::PixelBuffer outlineImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_OUTLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+      Devel::PixelBuffer outlineImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_OUTLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+
+      const float& blurRadius = viewModel.GetOutlineBlurRadius();
+
+      if(blurRadius > Math::MACHINE_EPSILON_1)
+      {
+        outlineImageBuffer.ApplyGaussianBlur(blurRadius);
+      }
 
       // Combine the two buffers
-      imageBuffer = CombineImageBuffer(imageBuffer, outlineImageBuffer, bufferWidth, bufferHeight);
+      CombineImageBuffer(imageBuffer, outlineImageBuffer, bufferWidth, bufferHeight, true);
     }
 
-    // @todo. Support shadow and underline for partial text later on.
+    // @todo. Support shadow for partial text later on.
 
     // Generate the shadow if enabled
-    const Vector2& shadowOffset = mModel->GetShadowOffset();
-    if(RENDER_OVERLAY_STYLE != behaviour && (fabsf(shadowOffset.x) > Math::MACHINE_EPSILON_1 || fabsf(shadowOffset.y) > Math::MACHINE_EPSILON_1))
+    const Vector2& shadowOffset = viewModel.GetShadowOffset();
+    const float    shadowAlpha  = viewModel.GetShadowColor().a;
+    if(RENDER_OVERLAY_STYLE != behaviour && fabsf(shadowAlpha) > Math::MACHINE_EPSILON_1 && (fabsf(shadowOffset.x) > Math::MACHINE_EPSILON_1 || fabsf(shadowOffset.y) > Math::MACHINE_EPSILON_1))
     {
       // Create the image buffer for shadow
-      Devel::PixelBuffer shadowImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_SHADOW, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+      Devel::PixelBuffer shadowImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_SHADOW, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
 
       // Check whether it will be a soft shadow
-      const float& blurRadius = mModel->GetShadowBlurRadius();
+      const float& blurRadius = viewModel.GetShadowBlurRadius();
 
       if(blurRadius > Math::MACHINE_EPSILON_1)
       {
@@ -733,503 +360,119 @@ PixelData Typesetter::Render(const Vector2& size, Toolkit::DevelText::TextDirect
       }
 
       // Combine the two buffers
-      imageBuffer = CombineImageBuffer(imageBuffer, shadowImageBuffer, bufferWidth, bufferHeight);
-    }
-
-    // Generate the underline if enabled
-    const bool underlineEnabled = mModel->IsUnderlineEnabled();
-    if(underlineEnabled && RENDER_OVERLAY_STYLE == behaviour)
-    {
-      // Create the image buffer for underline
-      Devel::PixelBuffer underlineImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
-
-      // Combine the two buffers
-      imageBuffer = CombineImageBuffer(imageBuffer, underlineImageBuffer, bufferWidth, bufferHeight);
+      CombineImageBuffer(imageBuffer, shadowImageBuffer, bufferWidth, bufferHeight, true);
     }
 
     // Generate the background if enabled
-    const bool backgroundEnabled   = mModel->IsBackgroundEnabled();
-    const bool backgroundMarkupSet = mModel->IsMarkupBackgroundColorSet();
+    const bool backgroundEnabled   = viewModel.IsBackgroundEnabled();
+    const bool backgroundMarkupSet = viewModel.IsMarkupBackgroundColorSet();
     if((backgroundEnabled || backgroundMarkupSet) && RENDER_OVERLAY_STYLE != behaviour)
     {
       Devel::PixelBuffer backgroundImageBuffer;
 
       if(backgroundEnabled)
       {
-        backgroundImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_BACKGROUND, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
+        backgroundImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_BACKGROUND, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
       }
       else
       {
-        backgroundImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, pixelFormat);
+        backgroundImageBuffer = Impl::CreateTransparentImageBuffer(bufferWidth, bufferHeight, pixelFormat);
       }
 
       if(backgroundMarkupSet)
       {
-        DrawGlyphsBackground(mModel, backgroundImageBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, penX, penY);
+        mImpl->DrawGlyphsBackground(backgroundImageBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, penX, penY);
       }
 
       // Combine the two buffers
-      imageBuffer = CombineImageBuffer(imageBuffer, backgroundImageBuffer, bufferWidth, bufferHeight);
+      CombineImageBuffer(imageBuffer, backgroundImageBuffer, bufferWidth, bufferHeight, true);
     }
 
-    // Generate the strikethrough if enabled
-    const bool strikethroughEnabled = mModel->IsStrikethroughEnabled();
-    if(strikethroughEnabled && RENDER_OVERLAY_STYLE == behaviour)
+    // Generate the background_with_mask if enabled
+    const bool backgroundWithCutoutEnabled = viewModel.IsBackgroundWithCutoutEnabled();
+    if((backgroundWithCutoutEnabled) && RENDER_OVERLAY_STYLE != behaviour)
     {
-      // Create the image buffer for strikethrough
-      Devel::PixelBuffer strikethroughImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_STRIKETHROUGH, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, endIndexOfGlyphs);
-
-      // Combine the two buffers
-      imageBuffer = CombineImageBuffer(imageBuffer, strikethroughImageBuffer, bufferWidth, bufferHeight);
-    }
-
-    // Markup-Processor
-
-    imageBuffer = ApplyMarkupProcessorOnPixelBuffer(imageBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, pixelFormat, penX, penY);
-  }
-
-  // Create the final PixelData for the combined image buffer
-  PixelData pixelData = Devel::PixelBuffer::Convert(imageBuffer);
-
-  return pixelData;
-}
-
-Devel::PixelBuffer Typesetter::CreateImageBuffer(const unsigned int bufferWidth, const unsigned int bufferHeight, Typesetter::Style style, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int horizontalOffset, int verticalOffset, GlyphIndex fromGlyphIndex, GlyphIndex toGlyphIndex)
-{
-  // Retrieve lines, glyphs, positions and colors from the view model.
-  const Length            modelNumberOfLines = mModel->GetNumberOfLines();
-  const LineRun* const    modelLinesBuffer   = mModel->GetLines();
-  const GlyphInfo* const  glyphsBuffer       = mModel->GetGlyphs();
-  const Vector2* const    positionBuffer     = mModel->GetLayout();
-  const Vector4* const    colorsBuffer       = mModel->GetColors();
-  const ColorIndex* const colorIndexBuffer   = mModel->GetColorIndices();
-  const GlyphInfo*        hyphens            = mModel->GetHyphens();
-  const Length*           hyphenIndices      = mModel->GetHyphenIndices();
-  const Length            hyphensCount       = mModel->GetHyphensCount();
-
-  // Elided text info. Indices according to elided text and Ellipsis position.
-  const auto startIndexOfGlyphs              = mModel->GetStartIndexOfElidedGlyphs();
-  const auto endIndexOfGlyphs                = mModel->GetEndIndexOfElidedGlyphs();
-  const auto firstMiddleIndexOfElidedGlyphs  = mModel->GetFirstMiddleIndexOfElidedGlyphs();
-  const auto secondMiddleIndexOfElidedGlyphs = mModel->GetSecondMiddleIndexOfElidedGlyphs();
-  const auto ellipsisPosition                = mModel->GetEllipsisPosition();
-
-  // Whether to use the default color.
-  const bool     useDefaultColor = (NULL == colorsBuffer);
-  const Vector4& defaultColor    = mModel->GetDefaultColor();
-
-  // Create and initialize the pixel buffer.
-  GlyphData glyphData;
-  glyphData.verticalOffset   = verticalOffset;
-  glyphData.width            = bufferWidth;
-  glyphData.height           = bufferHeight;
-  glyphData.bitmapBuffer     = CreateImageBuffer(bufferWidth, bufferHeight, pixelFormat);
-  glyphData.horizontalOffset = 0;
-
-  // Get a handle of the font client. Used to retrieve the bitmaps of the glyphs.
-  TextAbstraction::FontClient fontClient  = TextAbstraction::FontClient::Get();
-  Length                      hyphenIndex = 0;
-
-  const Character*              textBuffer                = mModel->GetTextBuffer();
-  float                         calculatedAdvance         = 0.f;
-  const Vector<CharacterIndex>& glyphToCharacterMap       = mModel->GetGlyphsToCharacters();
-  const CharacterIndex*         glyphToCharacterMapBuffer = glyphToCharacterMap.Begin();
-
-  // Traverses the lines of the text.
-  for(LineIndex lineIndex = 0u; lineIndex < modelNumberOfLines; ++lineIndex)
-  {
-    const LineRun& line = *(modelLinesBuffer + lineIndex);
-
-    // Sets the horizontal offset of the line.
-    glyphData.horizontalOffset = ignoreHorizontalAlignment ? 0 : static_cast<int>(line.alignmentOffset);
-    glyphData.horizontalOffset += horizontalOffset;
-
-    // Increases the vertical offset with the line's ascender.
-    glyphData.verticalOffset += static_cast<int>(line.ascender);
-
-    // Include line spacing after first line
-    if(lineIndex > 0u)
-    {
-      glyphData.verticalOffset += static_cast<int>(line.lineSpacing);
-    }
+      Devel::PixelBuffer backgroundImageBuffer;
 
-    // Retrieves the glyph's outline width
-    float outlineWidth = static_cast<float>(mModel->GetOutlineWidth());
+      backgroundImageBuffer = CreateFullBackgroundBuffer(bufferWidth, bufferHeight, viewModel.GetBackgroundColorWithCutout());
 
-    if(style == Typesetter::STYLE_OUTLINE)
-    {
-      glyphData.horizontalOffset -= outlineWidth;
-      if(lineIndex == 0u)
-      {
-        // Only need to add the vertical outline offset for the first line
-        glyphData.verticalOffset -= outlineWidth;
-      }
-    }
-    else if(style == Typesetter::STYLE_SHADOW)
-    {
-      const Vector2& shadowOffset = mModel->GetShadowOffset();
-      glyphData.horizontalOffset += shadowOffset.x - outlineWidth; // if outline enabled then shadow should offset from outline
-
-      if(lineIndex == 0u)
-      {
-        // Only need to add the vertical shadow offset for first line
-        glyphData.verticalOffset += shadowOffset.y - outlineWidth;
-      }
+      // Combine the two buffers
+      CombineImageBuffer(imageBuffer, backgroundImageBuffer, bufferWidth, bufferHeight, true);
     }
 
-    const bool  underlineEnabled     = mModel->IsUnderlineEnabled();
-    const bool  strikethroughEnabled = mModel->IsStrikethroughEnabled();
-    const float characterSpacing     = mModel->GetCharacterSpacing();
-
-    // Aggregate underline-style-properties from mModel
-    const UnderlineStyleProperties modelUnderlineProperties{mModel->GetUnderlineType(),
-                                                            mModel->GetUnderlineColor(),
-                                                            mModel->GetUnderlineHeight(),
-                                                            mModel->GetDashedUnderlineGap(),
-                                                            mModel->GetDashedUnderlineWidth(),
-                                                            true,
-                                                            true,
-                                                            true,
-                                                            true,
-                                                            true};
-
-    // Aggregate strikethrough-style-properties from mModel
-    const StrikethroughStyleProperties modelStrikethroughProperties{mModel->GetStrikethroughColor(),
-                                                                    mModel->GetStrikethroughHeight(),
-                                                                    true,
-                                                                    true};
-
-    // Get the underline runs.
-    const Length               numberOfUnderlineRuns = mModel->GetNumberOfUnderlineRuns();
-    Vector<UnderlinedGlyphRun> underlineRuns;
-    underlineRuns.Resize(numberOfUnderlineRuns);
-    mModel->GetUnderlineRuns(underlineRuns.Begin(), 0u, numberOfUnderlineRuns);
-
-    // Get the strikethrough runs.
-    const Length                  numberOfStrikethroughRuns = mModel->GetNumberOfStrikethroughRuns();
-    Vector<StrikethroughGlyphRun> strikethroughRuns;
-    strikethroughRuns.Resize(numberOfStrikethroughRuns);
-    mModel->GetStrikethroughRuns(strikethroughRuns.Begin(), 0u, numberOfStrikethroughRuns);
-
-    bool thereAreUnderlinedGlyphs    = false;
-    bool thereAreStrikethroughGlyphs = false;
-
-    float currentUnderlinePosition   = 0.0f;
-    float currentUnderlineHeight     = modelUnderlineProperties.height;
-    float maxUnderlineHeight         = currentUnderlineHeight;
-    auto  currentUnderlineProperties = modelUnderlineProperties;
-
-    float currentStrikethroughHeight     = modelStrikethroughProperties.height;
-    float maxStrikethroughHeight         = currentStrikethroughHeight;
-    auto  currentStrikethroughProperties = modelStrikethroughProperties;
-    float strikethroughStartingYPosition = 0.0f;
-
-    FontId lastFontId = 0;
-
-    float lineExtentLeft  = bufferWidth;
-    float lineExtentRight = 0.0f;
-    float baseline        = 0.0f;
-    bool  addHyphen       = false;
-
-    // Traverses the glyphs of the line.
-    const GlyphIndex startGlyphIndex = std::max(line.glyphRun.glyphIndex, startIndexOfGlyphs);
-    GlyphIndex       endGlyphIndex   = (line.isSplitToTwoHalves ? line.glyphRunSecondHalf.glyphIndex + line.glyphRunSecondHalf.numberOfGlyphs : line.glyphRun.glyphIndex + line.glyphRun.numberOfGlyphs) - 1u;
-    endGlyphIndex                    = std::min(endGlyphIndex, endIndexOfGlyphs);
-
-    for(GlyphIndex glyphIndex = startGlyphIndex; glyphIndex <= endGlyphIndex; ++glyphIndex)
+    if(RENDER_OVERLAY_STYLE == behaviour)
     {
-      if(glyphIndex < fromGlyphIndex || glyphIndex > toGlyphIndex)
-      {
-        // Ignore any glyph that out of the specified range
-        continue;
-      }
-
-      //To handle START case of ellipsis, the first glyph has been shifted
-      //glyphIndex represent indices in whole glyphs but elidedGlyphIndex represents indices in elided Glyphs
-      GlyphIndex elidedGlyphIndex = glyphIndex - startIndexOfGlyphs;
-
-      //To handle MIDDLE case of ellipsis, the first glyph in the second half of line has been shifted and skip the removed glyph from middle.
-      if(ellipsisPosition == DevelText::EllipsisPosition::MIDDLE)
-      {
-        if(glyphIndex > firstMiddleIndexOfElidedGlyphs &&
-           glyphIndex < secondMiddleIndexOfElidedGlyphs)
-        {
-          // Ignore any glyph that removed for MIDDLE ellipsis
-          continue;
-        }
-        if(glyphIndex >= secondMiddleIndexOfElidedGlyphs)
-        {
-          elidedGlyphIndex -= (secondMiddleIndexOfElidedGlyphs - firstMiddleIndexOfElidedGlyphs - 1u);
-        }
-      }
-
-      // Retrieve the glyph's info.
-      const GlyphInfo* glyphInfo;
-
-      if(addHyphen && hyphens)
-      {
-        glyphInfo = hyphens + hyphenIndex;
-        hyphenIndex++;
-      }
-      else
-      {
-        glyphInfo = glyphsBuffer + elidedGlyphIndex;
-      }
-
-      if((glyphInfo->width < Math::MACHINE_EPSILON_1000) ||
-         (glyphInfo->height < Math::MACHINE_EPSILON_1000))
-      {
-        // Nothing to do if the glyph's width or height is zero.
-        continue;
-      }
-
-      Vector<UnderlinedGlyphRun>::ConstIterator currentUnderlinedGlyphRunIt = underlineRuns.End();
-      const bool                                underlineGlyph              = underlineEnabled || IsGlyphUnderlined(glyphIndex, underlineRuns, currentUnderlinedGlyphRunIt);
-      currentUnderlineProperties                                            = GetCurrentUnderlineProperties(glyphIndex, underlineGlyph, underlineRuns, currentUnderlinedGlyphRunIt, modelUnderlineProperties);
-      currentUnderlineHeight                                                = currentUnderlineProperties.height;
-      thereAreUnderlinedGlyphs                                              = thereAreUnderlinedGlyphs || underlineGlyph;
-
-      Vector<StrikethroughGlyphRun>::ConstIterator currentStrikethroughGlyphRunIt = strikethroughRuns.End();
-      const bool                                   strikethroughGlyph             = strikethroughEnabled || IsGlyphStrikethrough(glyphIndex, strikethroughRuns, currentStrikethroughGlyphRunIt);
-      currentStrikethroughProperties                                              = GetCurrentStrikethroughProperties(glyphIndex, strikethroughGlyph, strikethroughRuns, currentStrikethroughGlyphRunIt, modelStrikethroughProperties);
-      currentStrikethroughHeight                                                  = currentStrikethroughProperties.height;
-      thereAreStrikethroughGlyphs                                                 = thereAreStrikethroughGlyphs || strikethroughGlyph;
-
-      // Are we still using the same fontId as previous
-      if((glyphInfo->fontId != lastFontId) && (strikethroughGlyph || underlineGlyph))
-      {
-        // We need to fetch fresh font underline metrics
-        FontMetrics fontMetrics;
-        fontClient.GetFontMetrics(glyphInfo->fontId, fontMetrics);
-
-        //The currentUnderlinePosition will be used for both Underline and/or Strikethrough
-        currentUnderlinePosition = FetchUnderlinePositionFromFontMetrics(fontMetrics);
-
-        if(underlineGlyph)
-        {
-          CalcualteUnderlineHeight(fontMetrics, currentUnderlineHeight, maxUnderlineHeight);
-        }
-
-        if(strikethroughGlyph)
-        {
-          CalcualteStrikethroughHeight(currentStrikethroughHeight, maxStrikethroughHeight);
-        }
-
-        // Update lastFontId because fontId is changed
-        lastFontId = glyphInfo->fontId; // Prevents searching for existing blocksizes when string of the same fontId.
-      }
-
-      // Retrieves the glyph's position.
-      Vector2 position = *(positionBuffer + elidedGlyphIndex);
-
-      if(addHyphen)
-      {
-        GlyphInfo tempInfo = *(glyphsBuffer + elidedGlyphIndex);
-        calculatedAdvance  = GetCalculatedAdvance(*(textBuffer + (*(glyphToCharacterMapBuffer + elidedGlyphIndex))), characterSpacing, tempInfo.advance);
-        position.x         = position.x + calculatedAdvance - tempInfo.xBearing + glyphInfo->xBearing;
-        position.y         = -glyphInfo->yBearing;
-      }
-
-      if(baseline < position.y + glyphInfo->yBearing)
+      if(viewModel.IsUnderlineEnabled())
       {
-        baseline = position.y + glyphInfo->yBearing;
-      }
-
-      // Calculate the positions of leftmost and rightmost glyphs in the current line
-      if(position.x < lineExtentLeft)
-      {
-        lineExtentLeft = position.x;
-      }
-
-      if(position.x + glyphInfo->width > lineExtentRight)
-      {
-        lineExtentRight = position.x + glyphInfo->width;
-      }
+        // Create the image buffer for underline
+        Devel::PixelBuffer underlineImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, startIndexOfGlyphs, endIndexOfGlyphs);
 
-      // Retrieves the glyph's color.
-      const ColorIndex colorIndex = useDefaultColor ? 0u : *(colorIndexBuffer + glyphIndex);
-
-      Vector4 color;
-      if(style == Typesetter::STYLE_SHADOW)
-      {
-        color = mModel->GetShadowColor();
-      }
-      else if(style == Typesetter::STYLE_OUTLINE)
-      {
-        color = mModel->GetOutlineColor();
+        // Combine the two buffers
+        CombineImageBuffer(imageBuffer, underlineImageBuffer, bufferWidth, bufferHeight, true);
       }
-      else
-      {
-        color = (useDefaultColor || (0u == colorIndex)) ? defaultColor : *(colorsBuffer + (colorIndex - 1u));
-      }
-
-      // Premultiply alpha
-      color.r *= color.a;
-      color.g *= color.a;
-      color.b *= color.a;
-
-      // Retrieves the glyph's bitmap.
-      glyphData.glyphBitmap.buffer = NULL;
-      glyphData.glyphBitmap.width  = glyphInfo->width; // Desired width and height.
-      glyphData.glyphBitmap.height = glyphInfo->height;
 
-      if(style != Typesetter::STYLE_OUTLINE && style != Typesetter::STYLE_SHADOW)
+      if(viewModel.IsStrikethroughEnabled())
       {
-        // Don't render outline for other styles
-        outlineWidth = 0.0f;
-      }
+        // Create the image buffer for strikethrough
+        Devel::PixelBuffer strikethroughImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_STRIKETHROUGH, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, endIndexOfGlyphs);
 
-      if(style != Typesetter::STYLE_UNDERLINE && style != Typesetter::STYLE_STRIKETHROUGH)
-      {
-        fontClient.CreateBitmap(glyphInfo->fontId,
-                                glyphInfo->index,
-                                glyphInfo->isItalicRequired,
-                                glyphInfo->isBoldRequired,
-                                glyphData.glyphBitmap,
-                                static_cast<int>(outlineWidth));
+        // Combine the two buffers
+        CombineImageBuffer(imageBuffer, strikethroughImageBuffer, bufferWidth, bufferHeight, true);
       }
 
-      // Sets the glyph's bitmap into the bitmap of the whole text.
-      if(NULL != glyphData.glyphBitmap.buffer)
+      // Markup-Processor for overlay styles
+      if(viewModel.IsMarkupProcessorEnabled() || viewModel.IsSpannedTextPlaced())
       {
-        if(style == Typesetter::STYLE_OUTLINE)
+        if(viewModel.IsMarkupUnderlineSet())
         {
-          // Set the position offset for the current glyph
-          glyphData.horizontalOffset -= glyphData.glyphBitmap.outlineOffsetX;
-          glyphData.verticalOffset -= glyphData.glyphBitmap.outlineOffsetY;
+          imageBuffer = ApplyUnderlineMarkupImageBuffer(imageBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, pixelFormat, penX, penY);
         }
 
-        // Set the buffer of the glyph's bitmap into the final bitmap's buffer
-        TypesetGlyph(glyphData,
-                     &position,
-                     &color,
-                     style,
-                     pixelFormat);
-
-        if(style == Typesetter::STYLE_OUTLINE)
+        if(viewModel.IsMarkupStrikethroughSet())
         {
-          // Reset the position offset for the next glyph
-          glyphData.horizontalOffset += glyphData.glyphBitmap.outlineOffsetX;
-          glyphData.verticalOffset += glyphData.glyphBitmap.outlineOffsetY;
-        }
-
-        // delete the glyphBitmap.buffer as it is now copied into glyphData.bitmapBuffer
-        delete[] glyphData.glyphBitmap.buffer;
-        glyphData.glyphBitmap.buffer = NULL;
-      }
-
-      if(hyphenIndices)
-      {
-        while((hyphenIndex < hyphensCount) && (glyphIndex > hyphenIndices[hyphenIndex]))
-        {
-          hyphenIndex++;
-        }
-
-        addHyphen = ((hyphenIndex < hyphensCount) && ((glyphIndex + 1) == hyphenIndices[hyphenIndex]));
-        if(addHyphen)
-        {
-          glyphIndex--;
+          imageBuffer = ApplyStrikethroughMarkupImageBuffer(imageBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, pixelFormat, penX, penY);
         }
       }
     }
-
-    // Draw the underline from the leftmost glyph to the rightmost glyph
-    if(thereAreUnderlinedGlyphs && style == Typesetter::STYLE_UNDERLINE)
-    {
-      DrawUnderline(bufferWidth, bufferHeight, glyphData, baseline, currentUnderlinePosition, maxUnderlineHeight, lineExtentLeft, lineExtentRight, modelUnderlineProperties, currentUnderlineProperties, line);
-    }
-
-    // Draw the background color from the leftmost glyph to the rightmost glyph
-    if(style == Typesetter::STYLE_BACKGROUND)
-    {
-      DrawBackgroundColor(mModel->GetBackgroundColor(), bufferWidth, bufferHeight, glyphData, baseline, line, lineExtentLeft, lineExtentRight);
-    }
-
-    // Draw the strikethrough from the leftmost glyph to the rightmost glyph
-    if(thereAreStrikethroughGlyphs && style == Typesetter::STYLE_STRIKETHROUGH)
-    {
-      //TODO : The currently implemented strikethrough creates a strikethrough on the line level. We need to create different strikethroughs the case of glyphs with different sizes.
-      strikethroughStartingYPosition = (glyphData.verticalOffset + baseline + currentUnderlinePosition) - ((line.ascender) * HALF); // Since Free Type font doesn't contain the strikethrough-position property, strikethrough position will be calculated by moving the underline position upwards by half the value of the line height.
-      DrawStrikethrough(bufferWidth, bufferHeight, glyphData, baseline, strikethroughStartingYPosition, maxStrikethroughHeight, lineExtentLeft, lineExtentRight, modelStrikethroughProperties, currentStrikethroughProperties, line);
-    }
-
-    // Increases the vertical offset with the line's descender.
-    glyphData.verticalOffset += static_cast<int>(-line.descender);
   }
 
-  return glyphData.bitmapBuffer;
+  return imageBuffer;
 }
 
-Devel::PixelBuffer Typesetter::CombineImageBuffer(Devel::PixelBuffer topPixelBuffer, Devel::PixelBuffer bottomPixelBuffer, const unsigned int bufferWidth, const unsigned int bufferHeight)
+Devel::PixelBuffer Typesetter::CreateFullBackgroundBuffer(const uint32_t bufferWidth, const uint32_t bufferHeight, const Vector4& backgroundColor)
 {
-  unsigned char* topBuffer    = topPixelBuffer.GetBuffer();
-  unsigned char* bottomBuffer = bottomPixelBuffer.GetBuffer();
+  const uint32_t bufferSizeInt        = bufferWidth * bufferHeight;
+  uint8_t        backgroundColorAlpha = static_cast<uint8_t>(backgroundColor.a * 255.f);
 
-  Devel::PixelBuffer combinedPixelBuffer;
+  Devel::PixelBuffer buffer = Devel::PixelBuffer::New(bufferWidth, bufferHeight, Pixel::RGBA8888);
 
-  if(topBuffer == NULL && bottomBuffer == NULL)
-  {
-    // Nothing to do if both buffers are empty.
-    return combinedPixelBuffer;
-  }
-
-  if(topBuffer == NULL)
-  {
-    // Nothing to do if topBuffer is empty.
-    return bottomPixelBuffer;
-  }
-
-  if(bottomBuffer == NULL)
-  {
-    // Nothing to do if bottomBuffer is empty.
-    return topPixelBuffer;
-  }
+  uint32_t* bitmapBuffer = reinterpret_cast<uint32_t*>(buffer.GetBuffer());
 
-  // Always combine two RGBA images
-  const unsigned int bufferSizeInt  = bufferWidth * bufferHeight;
-  const unsigned int bufferSizeChar = 4u * bufferSizeInt;
+  uint32_t packedBackgroundColor       = 0u;
+  uint8_t* packedBackgroundColorBuffer = reinterpret_cast<uint8_t*>(&packedBackgroundColor);
 
-  combinedPixelBuffer     = Devel::PixelBuffer::New(bufferWidth, bufferHeight, Pixel::RGBA8888);
-  uint8_t* combinedBuffer = reinterpret_cast<uint8_t*>(combinedPixelBuffer.GetBuffer());
-  memset(combinedBuffer, 0u, bufferSizeChar);
-
-  for(unsigned int pixelIndex = 0; pixelIndex < bufferSizeInt; pixelIndex++)
-  {
-    // If the alpha of the pixel in either buffer is not fully opaque, blend the two pixels.
-    // Otherwise, copy pixel from topBuffer to combinedBuffer.
-
-    unsigned int alphaBuffer1 = topBuffer[pixelIndex * 4 + 3];
+  // Write the color to the pixel buffer
+  *(packedBackgroundColorBuffer + 3u) = backgroundColorAlpha;
+  *(packedBackgroundColorBuffer + 2u) = static_cast<uint8_t>(backgroundColor.b * backgroundColorAlpha);
+  *(packedBackgroundColorBuffer + 1u) = static_cast<uint8_t>(backgroundColor.g * backgroundColorAlpha);
+  *(packedBackgroundColorBuffer)      = static_cast<uint8_t>(backgroundColor.r * backgroundColorAlpha);
 
-    if(alphaBuffer1 != 255)
-    {
-      // At least one pixel is not fully opaque
-      // "Over" blend the the pixel from topBuffer with the pixel in bottomBuffer
-      combinedBuffer[pixelIndex * 4]     = topBuffer[pixelIndex * 4] + (bottomBuffer[pixelIndex * 4] * (255 - topBuffer[pixelIndex * 4 + 3]) / 255);
-      combinedBuffer[pixelIndex * 4 + 1] = topBuffer[pixelIndex * 4 + 1] + (bottomBuffer[pixelIndex * 4 + 1] * (255 - topBuffer[pixelIndex * 4 + 3]) / 255);
-      combinedBuffer[pixelIndex * 4 + 2] = topBuffer[pixelIndex * 4 + 2] + (bottomBuffer[pixelIndex * 4 + 2] * (255 - topBuffer[pixelIndex * 4 + 3]) / 255);
-      combinedBuffer[pixelIndex * 4 + 3] = topBuffer[pixelIndex * 4 + 3] + (bottomBuffer[pixelIndex * 4 + 3] * (255 - topBuffer[pixelIndex * 4 + 3]) / 255);
-    }
-    else
-    {
-      // Copy the pixel from topBuffer to combinedBuffer
-      combinedBuffer[pixelIndex * 4]     = topBuffer[pixelIndex * 4];
-      combinedBuffer[pixelIndex * 4 + 1] = topBuffer[pixelIndex * 4 + 1];
-      combinedBuffer[pixelIndex * 4 + 2] = topBuffer[pixelIndex * 4 + 2];
-      combinedBuffer[pixelIndex * 4 + 3] = topBuffer[pixelIndex * 4 + 3];
-    }
-  }
+  std::fill(bitmapBuffer, bitmapBuffer + bufferSizeInt, packedBackgroundColor);
 
-  return combinedPixelBuffer;
+  return buffer;
 }
 
-Devel::PixelBuffer Typesetter::ApplyUnderlineMarkupImageBuffer(Devel::PixelBuffer topPixelBuffer, const unsigned int bufferWidth, const unsigned int bufferHeight, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int horizontalOffset, int verticalOffset)
+Devel::PixelBuffer Typesetter::ApplyUnderlineMarkupImageBuffer(Devel::PixelBuffer topPixelBuffer, const uint32_t bufferWidth, const uint32_t bufferHeight, const bool ignoreHorizontalAlignment, const Pixel::Format pixelFormat, const int32_t horizontalOffset, const int32_t verticalOffset)
 {
+  // Use l-value to make ensure it is not nullptr, so compiler happy.
+  auto& viewModel = *(mImpl->GetViewModel());
+
   // Underline-tags (this is for Markup case)
   // Get the underline runs.
-  const Length               numberOfUnderlineRuns = mModel->GetNumberOfUnderlineRuns();
+  const Length               numberOfUnderlineRuns = viewModel.GetNumberOfUnderlineRuns();
   Vector<UnderlinedGlyphRun> underlineRuns;
   underlineRuns.Resize(numberOfUnderlineRuns);
-  mModel->GetUnderlineRuns(underlineRuns.Begin(), 0u, numberOfUnderlineRuns);
+  viewModel.GetUnderlineRuns(underlineRuns.Begin(), 0u, numberOfUnderlineRuns);
 
   // Iterate on the consecutive underlined glyph run and connect them into one chunk of underlined characters.
   Vector<UnderlinedGlyphRun>::ConstIterator itGlyphRun    = underlineRuns.Begin();
@@ -1243,9 +486,10 @@ Devel::PixelBuffer Typesetter::ApplyUnderlineMarkupImageBuffer(Devel::PixelBuffe
     endGlyphIndex   = startGlyphIndex + itGlyphRun->glyphRun.numberOfGlyphs - 1;
 
     // Create the image buffer for underline
-    Devel::PixelBuffer underlineImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset, startGlyphIndex, endGlyphIndex);
+    Devel::PixelBuffer underlineImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset, startGlyphIndex, endGlyphIndex);
     // Combine the two buffers
-    topPixelBuffer = CombineImageBuffer(underlineImageBuffer, topPixelBuffer, bufferWidth, bufferHeight);
+    // Result pixel buffer will be stored into topPixelBuffer.
+    CombineImageBuffer(underlineImageBuffer, topPixelBuffer, bufferWidth, bufferHeight, false);
 
     itGlyphRun++;
   }
@@ -1253,14 +497,17 @@ Devel::PixelBuffer Typesetter::ApplyUnderlineMarkupImageBuffer(Devel::PixelBuffe
   return topPixelBuffer;
 }
 
-Devel::PixelBuffer Typesetter::ApplyStrikethroughMarkupImageBuffer(Devel::PixelBuffer topPixelBuffer, const unsigned int bufferWidth, const unsigned int bufferHeight, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int horizontalOffset, int verticalOffset)
+Devel::PixelBuffer Typesetter::ApplyStrikethroughMarkupImageBuffer(Devel::PixelBuffer topPixelBuffer, const uint32_t bufferWidth, const uint32_t bufferHeight, const bool ignoreHorizontalAlignment, const Pixel::Format pixelFormat, const int32_t horizontalOffset, const int32_t verticalOffset)
 {
+  // Use l-value to make ensure it is not nullptr, so compiler happy.
+  auto& viewModel = *(mImpl->GetViewModel());
+
   // strikethrough-tags (this is for Markup case)
   // Get the strikethrough runs.
-  const Length                  numberOfStrikethroughRuns = mModel->GetNumberOfStrikethroughRuns();
+  const Length                  numberOfStrikethroughRuns = viewModel.GetNumberOfStrikethroughRuns();
   Vector<StrikethroughGlyphRun> strikethroughRuns;
   strikethroughRuns.Resize(numberOfStrikethroughRuns);
-  mModel->GetStrikethroughRuns(strikethroughRuns.Begin(), 0u, numberOfStrikethroughRuns);
+  viewModel.GetStrikethroughRuns(strikethroughRuns.Begin(), 0u, numberOfStrikethroughRuns);
 
   // Iterate on the consecutive strikethrough glyph run and connect them into one chunk of strikethrough characters.
   Vector<StrikethroughGlyphRun>::ConstIterator itGlyphRun    = strikethroughRuns.Begin();
@@ -1274,9 +521,10 @@ Devel::PixelBuffer Typesetter::ApplyStrikethroughMarkupImageBuffer(Devel::PixelB
     endGlyphIndex   = startGlyphIndex + itGlyphRun->glyphRun.numberOfGlyphs - 1;
 
     // Create the image buffer for strikethrough
-    Devel::PixelBuffer strikethroughImageBuffer = CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_STRIKETHROUGH, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset, startGlyphIndex, endGlyphIndex);
+    Devel::PixelBuffer strikethroughImageBuffer = mImpl->CreateImageBuffer(bufferWidth, bufferHeight, Typesetter::STYLE_STRIKETHROUGH, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset, startGlyphIndex, endGlyphIndex);
     // Combine the two buffers
-    topPixelBuffer = CombineImageBuffer(strikethroughImageBuffer, topPixelBuffer, bufferWidth, bufferHeight);
+    // Result pixel buffer will be stored into topPixelBuffer.
+    CombineImageBuffer(strikethroughImageBuffer, topPixelBuffer, bufferWidth, bufferHeight, false);
 
     itGlyphRun++;
   }
@@ -1284,29 +532,54 @@ Devel::PixelBuffer Typesetter::ApplyStrikethroughMarkupImageBuffer(Devel::PixelB
   return topPixelBuffer;
 }
 
-Devel::PixelBuffer Typesetter::ApplyMarkupProcessorOnPixelBuffer(Devel::PixelBuffer topPixelBuffer, const unsigned int bufferWidth, const unsigned int bufferHeight, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int horizontalOffset, int verticalOffset)
+void Typesetter::SetMaskForImageBuffer(Devel::PixelBuffer& __restrict__ topPixelBuffer, Devel::PixelBuffer& __restrict__ bottomPixelBuffer, const uint32_t bufferWidth, const uint32_t bufferHeight, float originAlpha)
 {
-  // Apply the markup-Processor if enabled
-  const bool markupProcessorEnabled = mModel->IsMarkupProcessorEnabled();
-  if(markupProcessorEnabled)
-  {
-    topPixelBuffer = ApplyUnderlineMarkupImageBuffer(topPixelBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset);
+  // Assume that we always combine two RGBA images
+  // Jump with 4bytes for optimize runtime.
+  uint32_t* topBuffer    = reinterpret_cast<uint32_t*>(topPixelBuffer.GetBuffer());
+  uint32_t* bottomBuffer = reinterpret_cast<uint32_t*>(bottomPixelBuffer.GetBuffer());
 
-    topPixelBuffer = ApplyStrikethroughMarkupImageBuffer(topPixelBuffer, bufferWidth, bufferHeight, ignoreHorizontalAlignment, pixelFormat, horizontalOffset, verticalOffset);
+  if(topBuffer == nullptr || bottomBuffer == nullptr)
+  {
+    // Nothing to do if one of both buffers are empty.
+    return;
   }
 
-  return topPixelBuffer;
+  const uint32_t bufferSizeInt = bufferWidth * bufferHeight;
+
+  for(uint32_t pixelIndex = 0; pixelIndex < bufferSizeInt; ++pixelIndex)
+  {
+    uint32_t topBufferColor                       = *(topBuffer);
+    uint32_t bottomBufferColor                    = *(bottomBuffer);
+    uint8_t* __restrict__ topBufferColorBuffer    = reinterpret_cast<uint8_t*>(&topBufferColor);
+    uint8_t* __restrict__ bottomBufferColorBuffer = reinterpret_cast<uint8_t*>(&bottomBufferColor);
+
+    // Return the transparency of the text to original.
+    uint8_t originAlphaInt = originAlpha * 255;
+
+    uint8_t topAlpha    = topBufferColorBuffer[3];
+    uint8_t bottomAlpha = 255 - topAlpha;
+
+    // Manual blending.
+    bottomBufferColorBuffer[0] = MultiplyAndSummationAndNormalizeColor(topBufferColorBuffer[0], originAlphaInt, bottomBufferColorBuffer[0], bottomAlpha);
+    bottomBufferColorBuffer[1] = MultiplyAndSummationAndNormalizeColor(topBufferColorBuffer[1], originAlphaInt, bottomBufferColorBuffer[1], bottomAlpha);
+    bottomBufferColorBuffer[2] = MultiplyAndSummationAndNormalizeColor(topBufferColorBuffer[2], originAlphaInt, bottomBufferColorBuffer[2], bottomAlpha);
+    bottomBufferColorBuffer[3] = MultiplyAndSummationAndNormalizeColor(topBufferColorBuffer[3], originAlphaInt, bottomBufferColorBuffer[3], bottomAlpha);
+
+    *(bottomBuffer) = bottomBufferColor;
+
+    // Increase each buffer's pointer.
+    ++topBuffer;
+    ++bottomBuffer;
+  }
 }
 
 Typesetter::Typesetter(const ModelInterface* const model)
-: mModel(new ViewModel(model))
+: mImpl{std::make_unique<Impl>(model)}
 {
 }
 
-Typesetter::~Typesetter()
-{
-  delete mModel;
-}
+Typesetter::~Typesetter() = default;
 
 } // namespace Text