From de634c6f3e1324d3ad9b85ea23c6247ce633ecf4 Mon Sep 17 00:00:00 2001
From: Jeff Young <jeff@rokeby.ie>
Date: Mon, 5 Feb 2024 15:33:03 +0000
Subject: [PATCH] Generate tofu if we fail to decompose outline font glyph.

---
 common/font/outline_decomposer.cpp |  8 ++++----
 common/font/outline_font.cpp       | 31 +++++++++++++++++++++++++++++-
 include/font/outline_decomposer.h  |  2 +-
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/common/font/outline_decomposer.cpp b/common/font/outline_decomposer.cpp
index 0c66d8e854..83c8fcc5b7 100644
--- a/common/font/outline_decomposer.cpp
+++ b/common/font/outline_decomposer.cpp
@@ -122,7 +122,7 @@ int OUTLINE_DECOMPOSER::cubicTo( const FT_Vector* aFirstControlPoint,
 }
 
 
-void OUTLINE_DECOMPOSER::OutlineToSegments( std::vector<CONTOUR>* aContours )
+bool OUTLINE_DECOMPOSER::OutlineToSegments( std::vector<CONTOUR>* aContours )
 {
     m_contours = aContours;
 
@@ -138,12 +138,12 @@ void OUTLINE_DECOMPOSER::OutlineToSegments( std::vector<CONTOUR>* aContours )
     FT_Error e = FT_Outline_Decompose( &m_outline, &callbacks, this );
 
     if( e )
-    {
-        // TODO: handle error != 0
-    }
+        return false;
 
     for( CONTOUR& c : *m_contours )
         c.m_Winding = winding( c.m_Points );
+
+    return true;
 }
 
 
diff --git a/common/font/outline_font.cpp b/common/font/outline_font.cpp
index e569701c89..263aa0686b 100644
--- a/common/font/outline_font.cpp
+++ b/common/font/outline_font.cpp
@@ -328,7 +328,36 @@ VECTOR2I OUTLINE_FONT::getTextAsGlyphsUnlocked( BOX2I* aBBox,
             std::vector<CONTOUR> contours;
 
             OUTLINE_DECOMPOSER decomposer( face->glyph->outline );
-            decomposer.OutlineToSegments( &contours );
+
+            if( !decomposer.OutlineToSegments( &contours ) )
+            {
+                double  hb_advance = glyphPos[i].x_advance * GLYPH_SIZE_SCALER;
+                BOX2D   tofuBox( { scaler * 0.03, 0.0 },
+                                 { hb_advance - scaler * 0.02, scaler * 0.72 } );
+
+                contours.clear();
+
+                CONTOUR outline;
+                outline.m_Winding = 1;
+                outline.m_Orientation = FT_ORIENTATION_TRUETYPE;
+                outline.m_Points.push_back( tofuBox.GetPosition() );
+                outline.m_Points.push_back( { tofuBox.GetSize().x, tofuBox.GetPosition().y } );
+                outline.m_Points.push_back( tofuBox.GetSize() );
+                outline.m_Points.push_back( { tofuBox.GetPosition().x, tofuBox.GetSize().y } );
+                contours.push_back( outline );
+
+                CONTOUR hole;
+                tofuBox.Move( { scaler * 0.06, scaler * 0.06 } );
+                tofuBox.SetSize( { tofuBox.GetWidth() - scaler * 0.06,
+                                   tofuBox.GetHeight() - scaler * 0.06 } );
+                hole.m_Winding = 1;
+                hole.m_Orientation = FT_ORIENTATION_NONE;
+                hole.m_Points.push_back( tofuBox.GetPosition() );
+                hole.m_Points.push_back( { tofuBox.GetSize().x, tofuBox.GetPosition().y } );
+                hole.m_Points.push_back( tofuBox.GetSize() );
+                hole.m_Points.push_back( { tofuBox.GetPosition().x, tofuBox.GetSize().y } );
+                contours.push_back( hole );
+            }
 
             std::unique_ptr<OUTLINE_GLYPH> glyph = std::make_unique<OUTLINE_GLYPH>();
             std::vector<SHAPE_LINE_CHAIN>  holes;
diff --git a/include/font/outline_decomposer.h b/include/font/outline_decomposer.h
index 0b8f07ab0d..8838f7d911 100644
--- a/include/font/outline_decomposer.h
+++ b/include/font/outline_decomposer.h
@@ -54,7 +54,7 @@ class OUTLINE_DECOMPOSER
 public:
     OUTLINE_DECOMPOSER( FT_Outline& aOutline );
 
-    void OutlineToSegments( std::vector<CONTOUR>* aContours );
+    bool OutlineToSegments( std::vector<CONTOUR>* aContours );
 
 private:
     void newContour();