Plotters: better support of filled circles having a thickness set to 0.

Setting a line thickness = 0 for graphic objects (circle, rect, line) is
allowed but creates issues for circles that were plotted a non filled shapes
but having a outline thickness = 0.

common/plotters/GERBER_plotter.cpp

@@ -1000,6 +1000,31 @@ void GERBER_PLOTTER::ThickCircle( const wxPoint& pos, int diametre, int width,
 }
 
 
+void GERBER_PLOTTER::FilledCircle( const wxPoint& pos, int diametre,
+                              EDA_DRAW_MODE_T tracemode, void* aData )
+{
+    // A filled circle is a graphic item, not a pad.
+    // So it is drawn, not flashed.
+    GBR_METADATA *gbr_metadata = static_cast<GBR_METADATA*>( aData );
+
+    if( gbr_metadata )
+        formatNetAttribute( &gbr_metadata->m_NetlistMetadata );
+
+    if( tracemode == FILLED )
+    {
+        // Draw a circle of diameter = diametre/2 with a line thickness = radius,
+        // To create a filled circle
+        SetCurrentLineWidth( diametre/2, gbr_metadata );
+        Circle( pos, diametre/2, NO_FILL, DO_NOT_SET_LINE_WIDTH );
+    }
+    else
+    {
+        SetCurrentLineWidth( USE_DEFAULT_LINE_WIDTH, gbr_metadata );
+        Circle( pos, diametre, NO_FILL, DO_NOT_SET_LINE_WIDTH );
+    }
+}
+
+
 void GERBER_PLOTTER::FlashPadCircle( const wxPoint& pos, int diametre, EDA_DRAW_MODE_T trace_mode, void* aData )
 {
     wxSize size( diametre, diametre );

common/plotters/plotter.cpp

@@ -578,6 +578,19 @@ void PLOTTER::ThickCircle( const wxPoint& pos, int diametre, int width,
 }
 
 
+void PLOTTER::FilledCircle( const wxPoint& pos, int diametre,
+                            EDA_DRAW_MODE_T tracemode, void* aData )
+{
+    if( tracemode == FILLED )
+        Circle( pos, diametre, FILLED_SHAPE, 0 );
+    else
+    {
+        SetCurrentLineWidth( -1 );
+        Circle( pos, diametre, NO_FILL, -1 );
+    }
+}
+
+
 void PLOTTER::PlotPoly( const SHAPE_LINE_CHAIN& aCornerList, FILL_T aFill,
                        int aWidth, void * aData )
 {

common/plotters/plotter_gerber.h

@@ -67,6 +67,8 @@ public:
     // Currently, aScale and aMirror are not used in gerber plotter
     virtual void SetViewport( const wxPoint& aOffset, double aIusPerDecimil,
                           double aScale, bool aMirror ) override;
+
+    // Basic plot primitives
     virtual void Rect( const wxPoint& p1, const wxPoint& p2, FILL_T fill,
                        int width = USE_DEFAULT_LINE_WIDTH ) override;
     virtual void Circle( const wxPoint& pos, int diametre, FILL_T fill,
@@ -74,6 +76,7 @@ public:
     virtual void Arc( const wxPoint& aCenter, double aStAngle, double aEndAngle,
                       int aRadius, FILL_T aFill, int aWidth = USE_DEFAULT_LINE_WIDTH ) override;
 
+    // These functions plot an item and manage X2 gerber attributes
     virtual void ThickSegment( const wxPoint& start, const wxPoint& end, int width,
                                EDA_DRAW_MODE_T tracemode, void* aData ) override;
 
@@ -83,6 +86,9 @@ public:
                             EDA_DRAW_MODE_T tracemode, void* aData ) override;
     virtual void ThickCircle( const wxPoint& pos, int diametre, int width,
                               EDA_DRAW_MODE_T tracemode, void* aData ) override;
+    virtual void FilledCircle( const wxPoint& pos, int diametre,
+                              EDA_DRAW_MODE_T tracemode, void* aData ) override;
+
     /**
      * Gerber polygon: they can (and *should*) be filled with the
      * appropriate G36/G37 sequence

include/plotter.h

@@ -321,6 +321,9 @@ public:
                             EDA_DRAW_MODE_T tracemode, void* aData );
     virtual void ThickCircle( const wxPoint& pos, int diametre, int width,
                               EDA_DRAW_MODE_T tracemode, void* aData );
+    virtual void FilledCircle( const wxPoint& pos, int diametre,
+                              EDA_DRAW_MODE_T tracemode, void* aData );
+
 
     // Flash primitives
 

pcbnew/plot_brditems_plotter.cpp

@@ -578,7 +578,7 @@ void BRDITEMS_PLOTTER::PlotFootprintGraphicItem( FP_SHAPE* aShape )
         if( aShape->GetWidth() > 0 )
             m_plotter->ThickCircle( pos, radius * 2, thickness, GetPlotMode(), &gbr_metadata );
         else
-            m_plotter->Circle( pos, radius * 2, FILLED_SHAPE, -1 );
+            m_plotter->FilledCircle( pos, radius * 2, GetPlotMode(), &gbr_metadata );
 
         break;
 
@@ -859,7 +859,11 @@ void BRDITEMS_PLOTTER::PlotPcbShape( PCB_SHAPE* aShape )
 
     case S_CIRCLE:
         radius = KiROUND( GetLineLength( end, start ) );
-        m_plotter->ThickCircle( start, radius * 2, thickness, GetPlotMode(), &gbr_metadata );
+
+        if( thickness > 0 )
+            m_plotter->ThickCircle( start, radius * 2, thickness, GetPlotMode(), &gbr_metadata );
+        else
+            m_plotter->FilledCircle( start, radius * 2, GetPlotMode(), &gbr_metadata );
         break;
 
     case S_ARC: