Safety for negative pen widths.

common/plotters/plotter.cpp

@@ -594,8 +594,7 @@ void PLOTTER::ThickArc( const VECTOR2D& centre, const EDA_ANGLE& aStartAngle,
 }
 
 
-void PLOTTER::ThickArc( const EDA_SHAPE& aArcShape,
-                           OUTLINE_MODE aTraceMode, void* aData )
+void PLOTTER::ThickArc( const EDA_SHAPE& aArcShape, OUTLINE_MODE aTraceMode, void* aData )
 {
     VECTOR2D center = aArcShape.getCenter();
     VECTOR2D mid = aArcShape.GetArcMid();

include/eda_shape.h

@@ -107,7 +107,7 @@ public:
     void SetFillColor( const COLOR4D& aColor ) { m_fillColor = aColor; }
 
     void SetWidth( int aWidth )                { m_stroke.SetWidth( aWidth ); }
-    int GetWidth() const                       { return m_stroke.GetWidth(); }
+    virtual int GetWidth() const               { return m_stroke.GetWidth(); }
     virtual int GetEffectiveWidth() const      { return GetWidth(); }
 
     void           SetLineStyle( const PLOT_DASH_TYPE aStyle );

pcbnew/convert_shape_list_to_polygon.cpp

@@ -382,8 +382,8 @@ bool ConvertOutlineToPolygon( std::vector<PCB_SHAPE*>& aShapeList, SHAPE_POLY_SE
                         // Ensure the approximated Bezier shape is built
                         // a good value is between (Bezier curve width / 2) and (Bezier curve width)
                         // ( and at least 0.05 mm to avoid very small segments)
-                        int min_segm_lenght = std::max( pcbIUScale.mmToIU( 0.05 ), graphic->GetWidth() );
-                        graphic->RebuildBezierToSegmentsPointsList( min_segm_lenght );
+                        int min_segm_length = std::max( pcbIUScale.mmToIU( 0.05 ), graphic->GetWidth() );
+                        graphic->RebuildBezierToSegmentsPointsList( min_segm_length );
 
                         if( reverse )
                         {

pcbnew/pcb_shape.cpp

@@ -146,6 +146,16 @@ std::vector<VECTOR2I> PCB_SHAPE::GetConnectionPoints() const
 }
 
 
+int PCB_SHAPE::GetWidth() const
+{
+    // A stroke width of 0 in PCBNew means no-border, but negative stroke-widths are only used
+    // in EEschema (see SCH_SHAPE::GetPenWidth()).
+    // Since negative stroke widths can trip up down-stream code (such as the Gerber plotter), we
+    // weed them out here.
+    return std::max( EDA_SHAPE::GetWidth(), 0 );
+}
+
+
 void PCB_SHAPE::StyleFromSettings( const BOARD_DESIGN_SETTINGS& settings )
 {
     m_stroke.SetWidth( settings.GetLineThickness( GetLayer() ) );

pcbnew/pcb_shape.h

@@ -82,6 +82,8 @@ public:
     STROKE_PARAMS GetStroke() const override { return m_stroke; }
     void SetStroke( const STROKE_PARAMS& aStroke ) override { m_stroke = aStroke; }
 
+    int GetWidth() const override;
+
     void StyleFromSettings( const BOARD_DESIGN_SETTINGS& settings ) override;
 
     /**