Scaling feature for fixed-size fonts

Change-Id: I77dd56483de63e92a9c2927428aeadf030909b98

diff --git a/text/dali/devel-api/text-abstraction/font-client.cpp b/text/dali/devel-api/text-abstraction/font-client.cpp
index 377e33d..27feb02 100644 (file)
--- a/text/dali/devel-api/text-abstraction/font-client.cpp
+++ b/text/dali/devel-api/text-abstraction/font-client.cpp
@@ -132,9 +132,9 @@ void FontClient::GetFixedSizes( const FontFamily& fontFamily,
   GetImplementation(*this).GetFixedSizes( fontFamily, style, sizes );
 }
 
-void FontClient::GetFontMetrics( FontId fontId, FontMetrics& metrics )
+void FontClient::GetFontMetrics( FontId fontId, FontMetrics& metrics, int maxFixedSize )
 {
-  GetImplementation(*this).GetFontMetrics( fontId, metrics );
+  GetImplementation(*this).GetFontMetrics( fontId, metrics, maxFixedSize );
 }
 
 GlyphIndex FontClient::GetGlyphIndex( FontId fontId, Character charcode )
@@ -142,9 +142,9 @@ GlyphIndex FontClient::GetGlyphIndex( FontId fontId, Character charcode )
   return GetImplementation(*this).GetGlyphIndex( fontId, charcode );
 }
 
-bool FontClient::GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal )
+bool FontClient::GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal, int maxFixedSize )
 {
-  return GetImplementation(*this).GetGlyphMetrics( array, size, horizontal );
+  return GetImplementation(*this).GetGlyphMetrics( array, size, horizontal, maxFixedSize );
 }
 
 BufferImage FontClient::CreateBitmap( FontId fontId, GlyphIndex glyphIndex )

diff --git a/text/dali/devel-api/text-abstraction/font-client.h b/text/dali/devel-api/text-abstraction/font-client.h
index 03d23a0..f069bd3 100644 (file)
--- a/text/dali/devel-api/text-abstraction/font-client.h
+++ b/text/dali/devel-api/text-abstraction/font-client.h
@@ -244,8 +244,9 @@ public:
    *
    * @param[in] fontId The ID of the font for the required glyph.
    * @param[out] metrics The font metrics.
+   * @param[in] maxFixedSize The metrics for fixed-size fonts will be down-scaled, when exceeding this maximum value in pixels.
    */
-  void GetFontMetrics( FontId fontId, FontMetrics& metrics );
+  void GetFontMetrics( FontId fontId, FontMetrics& metrics, int maxFixedSize = 0 );
 
   /**
    * @brief Retrieve the glyph index for a UTF-32 character code.
@@ -264,9 +265,10 @@ public:
    * On return, the glyph's size value will be initialized. The bearing value will be updated by adding the font's glyph bearing to the one set by the shaping tool.
    * @param[in] size The size of the array.
    * @param[in] horizontal True for horizontal layouts (set to false for vertical layouting).
+   * @param[in] maxFixedSize The metrics for fixed-size fonts will be down-scaled, when exceeding this maximum value in pixels.
    * @return True if all of the requested metrics were found.
    */
-  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal = true );
+  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal = true, int maxFixedSize = 0 );
 
   /**
    * @brief Render a bitmap representation of a glyph.

diff --git a/text/dali/devel-api/text-abstraction/glyph-info.cpp b/text/dali/devel-api/text-abstraction/glyph-info.cpp
index 78f18e2..2d7c811 100644 (file)
--- a/text/dali/devel-api/text-abstraction/glyph-info.cpp
+++ b/text/dali/devel-api/text-abstraction/glyph-info.cpp
@@ -31,7 +31,8 @@ GlyphInfo::GlyphInfo()
   height( 0 ),
   xBearing( 0 ),
   yBearing( 0 ),
-  advance( 0 )
+  advance( 0 ),
+  scaleFactor( 0 )
 {
 }
 
@@ -42,7 +43,8 @@ GlyphInfo::GlyphInfo( FontId font, GlyphIndex i )
   height( 0 ),
   xBearing( 0 ),
   yBearing( 0 ),
-  advance( 0 )
+  advance( 0 ),
+  scaleFactor( 0 )
 {
 }
 

diff --git a/text/dali/devel-api/text-abstraction/glyph-info.h b/text/dali/devel-api/text-abstraction/glyph-info.h
index c901c55..952a302 100644 (file)
--- a/text/dali/devel-api/text-abstraction/glyph-info.h
+++ b/text/dali/devel-api/text-abstraction/glyph-info.h
@@ -46,13 +46,14 @@ struct DALI_IMPORT_API GlyphInfo
    */
   GlyphInfo( FontId font, GlyphIndex i );
 
-  FontId fontId;    ///< Identifies the font containing the glyph
-  GlyphIndex index; ///< Uniquely identifies a glyph for a given FontId
-  float width;      ///< The width of the glyph
-  float height;     ///< The height of the glyph
-  float xBearing;   ///< The distance from the cursor position to the leftmost border of the glyph
-  float yBearing;   ///< The distance from the baseline to the topmost border of the glyph
-  float advance;    ///< The distance to move the cursor for this glyph
+  FontId fontId;     ///< Identifies the font containing the glyph
+  GlyphIndex index;  ///< Uniquely identifies a glyph for a given FontId
+  float width;       ///< The width of the glyph
+  float height;      ///< The height of the glyph
+  float xBearing;    ///< The distance from the cursor position to the leftmost border of the glyph
+  float yBearing;    ///< The distance from the baseline to the topmost border of the glyph
+  float advance;     ///< The distance to move the cursor for this glyph
+  float scaleFactor; ///< The scaling applied (fixed-size fonts only)
 };
 
 } // Dali

diff --git a/text/dali/internal/text-abstraction/font-client-impl.cpp b/text/dali/internal/text-abstraction/font-client-impl.cpp
index 9b5d5d2..c53b4cf 100644 (file)
--- a/text/dali/internal/text-abstraction/font-client-impl.cpp
+++ b/text/dali/internal/text-abstraction/font-client-impl.cpp
@@ -179,11 +179,11 @@ FontId FontClient::GetFontId( const FontFamily& fontFamily,
                              faceIndex );
 }
 
-void FontClient::GetFontMetrics( FontId fontId, FontMetrics& metrics )
+void FontClient::GetFontMetrics( FontId fontId, FontMetrics& metrics, int maxFixedSize )
 {
   CreatePlugin();
 
-  return mPlugin->GetFontMetrics( fontId, metrics );
+  return mPlugin->GetFontMetrics( fontId, metrics, maxFixedSize );
 }
 
 GlyphIndex FontClient::GetGlyphIndex( FontId fontId, Character charcode )
@@ -193,11 +193,11 @@ GlyphIndex FontClient::GetGlyphIndex( FontId fontId, Character charcode )
   return mPlugin->GetGlyphIndex( fontId, charcode );
 }
 
-bool FontClient::GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal )
+bool FontClient::GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal, int maxFixedSize )
 {
   CreatePlugin();
 
-  return mPlugin->GetGlyphMetrics( array, size, horizontal );
+  return mPlugin->GetGlyphMetrics( array, size, horizontal, maxFixedSize );
 }
 
 BufferImage FontClient::CreateBitmap( FontId fontId, GlyphIndex glyphIndex )

diff --git a/text/dali/internal/text-abstraction/font-client-impl.h b/text/dali/internal/text-abstraction/font-client-impl.h
index b221cb9..4e3edec 100644 (file)
--- a/text/dali/internal/text-abstraction/font-client-impl.h
+++ b/text/dali/internal/text-abstraction/font-client-impl.h
@@ -134,7 +134,7 @@ public:
   /**
    * @copydoc Dali::FontClient::GetFontMetrics()
    */
-  void GetFontMetrics( FontId fontId, FontMetrics& metrics );
+  void GetFontMetrics( FontId fontId, FontMetrics& metrics, int maxFixedSize );
 
   /**
    * @copydoc Dali::FontClient::GetGlyphIndex()
@@ -144,7 +144,7 @@ public:
   /**
    * @copydoc Dali::FontClient::GetGlyphMetrics()
    */
-  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal );
+  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal, int maxFixedSize );
 
   /**
    * @copydoc Dali::FontClient::CreateBitmap()

diff --git a/text/dali/internal/text-abstraction/font-client-plugin-impl.cpp b/text/dali/internal/text-abstraction/font-client-plugin-impl.cpp
index 18a4feb..23609ce 100644 (file)
--- a/text/dali/internal/text-abstraction/font-client-plugin-impl.cpp
+++ b/text/dali/internal/text-abstraction/font-client-plugin-impl.cpp
@@ -448,15 +448,30 @@ void FontClient::Plugin::ValidateFont( const FontFamily& fontFamily,
   FcPatternDestroy( fontFamilyPattern );
 }
 
-
-
 void FontClient::Plugin::GetFontMetrics( FontId fontId,
-                                         FontMetrics& metrics )
+                                         FontMetrics& metrics,
+                                         int maxFixedSize )
 {
   if( fontId > 0 &&
       fontId-1 < mFontCache.size() )
   {
-    metrics = mFontCache[fontId-1].mMetrics;
+    const CacheItem& font = mFontCache[fontId-1];
+
+    metrics = font.mMetrics;
+
+    // Adjust the metrics if the fixed-size font should be down-scaled
+    if( font.mIsFixedSizeBitmap &&
+        ( maxFixedSize > 0 ) &&
+        ( font.mFixedHeightPixels > maxFixedSize ) )
+    {
+      float scaleFactor = static_cast<float>(maxFixedSize) / static_cast<float>(font.mFixedHeightPixels);
+
+      metrics.ascender           *= scaleFactor;
+      metrics.descender          *= scaleFactor;
+      metrics.height             *= scaleFactor;
+      metrics.underlinePosition  *= scaleFactor;
+      metrics.underlineThickness *= scaleFactor;
+    }
   }
   else
   {
@@ -482,7 +497,8 @@ GlyphIndex FontClient::Plugin::GetGlyphIndex( FontId fontId,
 
 bool FontClient::Plugin::GetGlyphMetrics( GlyphInfo* array,
                                           uint32_t size,
-                                          bool horizontal )
+                                          bool horizontal,
+                                          int maxFixedSize )
 {
   bool success( true );
 
@@ -493,20 +509,37 @@ bool FontClient::Plugin::GetGlyphMetrics( GlyphInfo* array,
     if( fontId > 0 &&
         fontId-1 < mFontCache.size() )
     {
-      FT_Face ftFace = mFontCache[fontId-1].mFreeTypeFace;
+      const CacheItem& font = mFontCache[fontId-1];
+
+      FT_Face ftFace = font.mFreeTypeFace;
 
 #ifdef FREETYPE_BITMAP_SUPPORT
       // Check to see if we should be loading a Fixed Size bitmap?
-      if ( mFontCache[fontId-1].mIsFixedSizeBitmap )
+      if ( font.mIsFixedSizeBitmap )
       {
         int error = FT_Load_Glyph( ftFace, array[i].index, FT_LOAD_COLOR );
         if ( FT_Err_Ok == error )
         {
-          array[i].width = mFontCache[ fontId -1 ].mFixedWidthPixels;
-          array[i].height = mFontCache[ fontId -1 ].mFixedHeightPixels;
-          array[i].advance = mFontCache[ fontId -1 ].mFixedWidthPixels;
+          array[i].width = font.mFixedWidthPixels;
+          array[i].height = font.mFixedHeightPixels;
+          array[i].advance = font.mFixedWidthPixels;
           array[i].xBearing = 0.0f;
-          array[i].yBearing = mFontCache[ fontId -1 ].mFixedHeightPixels;
+          array[i].yBearing = font.mFixedHeightPixels;
+
+          // Adjust the metrics if the fixed-size font should be down-scaled
+          if( ( maxFixedSize > 0 ) &&
+              ( font.mFixedHeightPixels > maxFixedSize ) )
+          {
+            float scaleFactor = static_cast<float>(maxFixedSize) / static_cast<float>(font.mFixedHeightPixels);
+
+            array[i].width    *= scaleFactor;
+            array[i].height   *= scaleFactor;
+            array[i].advance  *= scaleFactor;
+            array[i].xBearing *= scaleFactor;
+            array[i].yBearing *= scaleFactor;
+
+            array[i].scaleFactor = scaleFactor;
+          }
         }
         else
         {
@@ -643,7 +676,7 @@ const GlyphInfo& FontClient::Plugin::GetEllipsisGlyph( PointSize26Dot6 pointSize
   item.glyph.index = FT_Get_Char_Index( mFontCache[item.glyph.fontId-1].mFreeTypeFace,
                                         ELLIPSIS_CHARACTER );
 
-  GetGlyphMetrics( &item.glyph, 1u, true );
+  GetGlyphMetrics( &item.glyph, 1u, true, 0 );
 
   return item.glyph;
 }
@@ -792,9 +825,9 @@ FontId FontClient::Plugin::CreateFont( const FontPath& path,
             float fixedHeight = static_cast< float >( ftFace->available_sizes[ i ].height );
 
             // Indicate that the font is a fixed sized bitmap
-            FontMetrics metrics( fixedHeight,
+            FontMetrics metrics( fixedHeight, // The ascender in pixels.
                                  0.0f,
-                                 fixedHeight,
+                                 fixedHeight, // The height in pixels.
                                  0.0f,
                                  0.0f );
 

diff --git a/text/dali/internal/text-abstraction/font-client-plugin-impl.h b/text/dali/internal/text-abstraction/font-client-plugin-impl.h
index 5032ef2..b292178 100644 (file)
--- a/text/dali/internal/text-abstraction/font-client-plugin-impl.h
+++ b/text/dali/internal/text-abstraction/font-client-plugin-impl.h
@@ -208,7 +208,7 @@ struct FontClient::Plugin
   /**
    * @copydoc Dali::FontClient::GetFontMetrics()
    */
-  void GetFontMetrics( FontId fontId, FontMetrics& metrics );
+  void GetFontMetrics( FontId fontId, FontMetrics& metrics, int maxFixedSize );
 
   /**
    * @copydoc Dali::FontClient::GetGlyphIndex()
@@ -218,7 +218,7 @@ struct FontClient::Plugin
   /**
    * @copydoc Dali::FontClient::GetGlyphMetrics()
    */
-  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal );
+  bool GetGlyphMetrics( GlyphInfo* array, uint32_t size, bool horizontal, int maxFixedSize );
 
   /**
    * @copydoc Dali::FontClient::CreateBitmap()