Underline for hypertext rollovers.

common/font/font.cpp

@@ -176,7 +176,8 @@ void FONT::Draw( KIGFX::GAL* aGal, const wxString& aText, const VECTOR2I& aPosit
     for( size_t i = 0; i < strings_list.GetCount(); i++ )
     {
         drawSingleLineText( aGal, nullptr, strings_list[i], positions[i], aAttrs.m_Size,
-                            aAttrs.m_Angle, aAttrs.m_Mirrored, aPosition, aAttrs.m_Italic );
+                            aAttrs.m_Angle, aAttrs.m_Mirrored, aPosition, aAttrs.m_Italic,
+                            aAttrs.m_Underlined );
     }
 }
 
@@ -245,7 +246,7 @@ VECTOR2I FONT::drawMarkup( BOX2I* aBoundingBox, std::vector<std::unique_ptr<GLYP
 void FONT::drawSingleLineText( KIGFX::GAL* aGal, BOX2I* aBoundingBox, const wxString& aText,
                                const VECTOR2I& aPosition, const VECTOR2I& aSize,
                                const EDA_ANGLE& aAngle, bool aMirror, const VECTOR2I& aOrigin,
-                               bool aItalic ) const
+                               bool aItalic, bool aUnderline ) const
 {
     if( !aGal )
         return;
@@ -255,6 +256,9 @@ void FONT::drawSingleLineText( KIGFX::GAL* aGal, BOX2I* aBoundingBox, const wxSt
     if( aItalic )
         textStyle |= TEXT_STYLE::ITALIC;
 
+    if( aUnderline )
+        textStyle |= TEXT_STYLE::UNDERLINE;
+
     std::vector<std::unique_ptr<GLYPH>> glyphs;
 
     (void) drawMarkup( aBoundingBox, &glyphs, aText, aPosition, aSize, aAngle, aMirror, aOrigin,

common/font/outline_font.cpp

@@ -141,6 +141,16 @@ double OUTLINE_FONT::ComputeOverbarVerticalPosition( double aGlyphHeight ) const
 }
 
 
+/**
+ * Compute the vertical position of an underline.  This is the distance between the text
+ * baseline and the underline.
+ */
+double OUTLINE_FONT::ComputeUnderlineVerticalPosition( double aGlyphHeight ) const
+{
+    return aGlyphHeight * m_underlineOffsetScaler;
+}
+
+
 /**
  * Compute the distance (interline) between 2 lines of text (for multiline texts).  This is
  * the distance between baselines, not the space between line bounding boxes.

common/font/stroke_font.cpp

@@ -46,6 +46,9 @@ using namespace KIFONT;
 ///< Factor that determines relative vertical position of the overbar.
 static constexpr double OVERBAR_POSITION_FACTOR = 1.33;
 
+///< Factor that determines relative vertical position of the underline.
+static constexpr double UNDERLINE_POSITION_FACTOR = -0.16;
+
 ///< Scale factor for a glyph
 static constexpr double STROKE_FONT_SCALE = 1.0 / 21.0;
 
@@ -210,6 +213,12 @@ double STROKE_FONT::ComputeOverbarVerticalPosition( double aGlyphHeight ) const
 }
 
 
+double STROKE_FONT::ComputeUnderlineVerticalPosition( double aGlyphHeight ) const
+{
+    return aGlyphHeight * UNDERLINE_POSITION_FACTOR;
+}
+
+
 VECTOR2I STROKE_FONT::GetTextAsGlyphs( BOX2I* aBBox, std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
                                        const wxString& aText, const VECTOR2I& aSize,
                                        const VECTOR2I& aPosition, const EDA_ANGLE& aAngle,
@@ -313,6 +322,29 @@ VECTOR2I STROKE_FONT::GetTextAsGlyphs( BOX2I* aBBox, std::vector<std::unique_ptr
         }
     }
 
+    if( aTextStyle & TEXT_STYLE::UNDERLINE )
+    {
+        barOffset.y = ComputeUnderlineVerticalPosition( glyphSize.y );
+
+        if( aTextStyle & TEXT_STYLE::ITALIC )
+            barOffset.x = barOffset.y * ITALIC_TILT;
+
+        VECTOR2D barStart( aPosition.x + barOffset.x + barTrim, cursor.y - barOffset.y );
+        VECTOR2D barEnd( cursor.x + barOffset.x - barTrim, cursor.y - barOffset.y );
+
+        if( aGlyphs )
+        {
+            STROKE_GLYPH underlineGlyph;
+
+            underlineGlyph.AddPoint( barStart );
+            underlineGlyph.AddPoint( barEnd );
+            underlineGlyph.Finalize();
+
+            aGlyphs->push_back( underlineGlyph.Transform( { 1.0, 1.0 }, { 0, 0 }, false,
+                                                          aAngle, aMirror, aOrigin ) );
+        }
+    }
+
     if( aBBox )
     {
         aBBox->SetOrigin( aPosition );

include/font/font.h

@@ -46,7 +46,8 @@ enum TEXT_STYLE
     ITALIC = 1 << 1,
     SUBSCRIPT = 1 << 2,
     SUPERSCRIPT = 1 << 3,
-    OVERBAR = 1 << 4
+    OVERBAR = 1 << 4,
+    UNDERLINE = 1 << 5
 };
 
 
@@ -159,6 +160,12 @@ public:
      */
     virtual double ComputeOverbarVerticalPosition( double aGlyphHeight ) const = 0;
 
+    /**
+     * Compute the vertical position of an underline.  This is the distance between the text
+     * baseline and the underline.
+     */
+    virtual double ComputeUnderlineVerticalPosition( double aGlyphHeight ) const = 0;
+
     /**
      * Compute the distance (interline) between 2 lines of text (for multiline texts).  This is
      * the distance between baselines, not the space between line bounding boxes.
@@ -218,7 +225,7 @@ protected:
     void drawSingleLineText( KIGFX::GAL* aGal, BOX2I* aBoundingBox, const wxString& aText,
                              const VECTOR2I& aPosition, const VECTOR2I& aSize,
                              const EDA_ANGLE& aAngle, bool aMirror, const VECTOR2I& aOrigin,
-                             bool aItalic ) const;
+                             bool aItalic, bool aUnderline ) const;
 
     /**
      * Computes the bounding box for a single line of text.

include/font/outline_font.h

@@ -83,6 +83,12 @@ public:
      */
     double ComputeOverbarVerticalPosition( double aGlyphHeight ) const override;
 
+    /**
+     * Compute the vertical position of an underline.  This is the distance between the text
+     * baseline and the underline.
+     */
+    double ComputeUnderlineVerticalPosition( double aGlyphHeight ) const override;
+
     /**
      * Compute the distance (interline) between 2 lines of text (for multiline texts).  This is
      * the distance between baselines, not the space between line bounding boxes.
@@ -142,6 +148,8 @@ private:
     // with 0.64.
     static constexpr double m_subscriptSuperscriptSize = 0.64;
 
+    static constexpr double m_underlineOffsetScaler = -0.16;
+
     int faceSize( int aSize ) const
     {
         return aSize * m_charSizeScaler * m_outlineFontSizeCompensation;

include/font/stroke_font.h

@@ -70,6 +70,12 @@ public:
      */
     double ComputeOverbarVerticalPosition( double aGlyphHeight ) const override;
 
+    /**
+     * Compute the vertical position of an underline.  This is the distance between the text
+     * baseline and the underline.
+     */
+    double ComputeUnderlineVerticalPosition( double aGlyphHeight ) const override;
+
     /**
      * Compute the distance (interline) between 2 lines of text (for multiline texts).  This is
      * the distance between baselines, not the space between line bounding boxes.