Improve SHAPE_LINE_CHAIN arc plotting.

It still doesn't get it quite right as it restarts
the lineStyle pattern at each segment/arc transition.

common/plotters/GERBER_plotter.cpp

@@ -851,14 +851,7 @@ void GERBER_PLOTTER::Rect( const VECTOR2I& p1, const VECTOR2I& p2, FILL_T fill,
                            int aCornerRadius )
 {
     if( aCornerRadius > 0 )
-    {
-        BOX2I box( p1, VECTOR2I( p2.x - p1.x, p2.y - p1.y ) );
-        box.Normalize();
-        SHAPE_RECT rect( box );
-        rect.SetRadius( aCornerRadius );
-        PlotPoly( rect.Outline(), fill, width, nullptr );
-        return;
-    }
+        wxFAIL_MSG( wxT( "GERBER_PLOTTER must use PlotPolyAsRegion() for rounded-corner rectangles!" ) );
 
     std::vector<VECTOR2I> cornerList;
 

common/plotters/PDF_plotter.cpp

@@ -386,18 +386,10 @@ void PDF_PLOTTER::Circle( const VECTOR2I& pos, int diametre, FILL_T aFill, int w
 }
 
 
-void PDF_PLOTTER::Arc( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
-                       const EDA_ANGLE& aAngle, double aRadius, FILL_T aFill, int aWidth )
+std::string PDF_PLOTTER::arcPath( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
+                                  const EDA_ANGLE& aAngle, double aRadius )
 {
-    wxASSERT( m_workFile );
-
-    SetCurrentLineWidth( aWidth );
-
-    if( aRadius <= 0 )
-    {
-        Circle( aCenter, GetCurrentLineWidth(), FILL_T::FILLED_SHAPE, 0 );
-        return;
-    }
+    std::string path;
 
     /*
      * Arcs are not so easily approximated by beziers (in the general case), so we approximate
@@ -416,20 +408,39 @@ void PDF_PLOTTER::Arc( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
     start.x = KiROUND( aCenter.x + aRadius * ( -startAngle ).Cos() );
     start.y = KiROUND( aCenter.y + aRadius * ( -startAngle ).Sin() );
     VECTOR2D pos_dev = userToDeviceCoordinates( start );
-    fmt::print( m_workFile, "{:g} {:g} m ", pos_dev.x, pos_dev.y );
+    path += fmt::format( "{:g} {:g} m ", pos_dev.x, pos_dev.y );
 
     for( EDA_ANGLE ii = startAngle + delta; ii < endAngle; ii += delta )
     {
         end.x = KiROUND( aCenter.x + aRadius * ( -ii ).Cos() );
         end.y = KiROUND( aCenter.y + aRadius * ( -ii ).Sin() );
         pos_dev = userToDeviceCoordinates( end );
-        fmt::print( m_workFile, "{:g} {:g} l ", pos_dev.x, pos_dev.y );
+        path += fmt::format( "{:g} {:g} l ", pos_dev.x, pos_dev.y );
     }
 
     end.x = KiROUND( aCenter.x + aRadius * ( -endAngle ).Cos() );
     end.y = KiROUND( aCenter.y + aRadius * ( -endAngle ).Sin() );
     pos_dev = userToDeviceCoordinates( end );
-    fmt::print( m_workFile, "{:g} {:g} l ", pos_dev.x, pos_dev.y );
+    path += fmt::format( "{:g} {:g} l ", pos_dev.x, pos_dev.y );
+
+    return path;
+}
+
+
+void PDF_PLOTTER::Arc( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
+                       const EDA_ANGLE& aAngle, double aRadius, FILL_T aFill, int aWidth )
+{
+    wxASSERT( m_workFile );
+
+    SetCurrentLineWidth( aWidth );
+
+    if( aRadius <= 0 )
+    {
+        Circle( aCenter, GetCurrentLineWidth(), FILL_T::FILLED_SHAPE, 0 );
+        return;
+    }
+
+    fmt::print( m_workFile, "{}", arcPath( aCenter, aStartAngle, aAngle, aRadius ) );
 
     // The arc is drawn... if not filled we stroke it, otherwise we finish
     // closing the pie at the center
@@ -439,7 +450,7 @@ void PDF_PLOTTER::Arc( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
     }
     else
     {
-        pos_dev = userToDeviceCoordinates( aCenter );
+        VECTOR2D pos_dev = userToDeviceCoordinates( aCenter );
         fmt::println( m_workFile, "{:g} {:g} l b", pos_dev.x, pos_dev.y );
     }
 }
@@ -480,16 +491,43 @@ void PDF_PLOTTER::PlotPoly( const std::vector<VECTOR2I>& aCornerList, FILL_T aFi
 void PDF_PLOTTER::PlotPoly( const SHAPE_LINE_CHAIN& aCornerList, FILL_T aFill, int aWidth,
                             void* aData )
 {
-    std::vector<VECTOR2I> cornerList;
-    cornerList.reserve( aCornerList.PointCount() );
+    SetCurrentLineWidth( aWidth );
 
-    for( int ii = 0; ii < aCornerList.PointCount(); ii++ )
-        cornerList.emplace_back( aCornerList.CPoint( ii ) );
+    std::set<size_t> handledArcs;
 
-    if( aCornerList.IsClosed() && cornerList.front() != cornerList.back() )
-        cornerList.emplace_back( aCornerList.CPoint( 0 ) );
+    for( int ii = 0; ii < aCornerList.SegmentCount(); ++ii )
+    {
+        if( aCornerList.IsArcSegment( ii ) )
+        {
+            size_t arcIndex = aCornerList.ArcIndex( ii );
 
-    PlotPoly( cornerList, aFill, aWidth, aData );
+            if( !handledArcs.contains( arcIndex ) )
+            {
+                handledArcs.insert( arcIndex );
+                const SHAPE_ARC& arc( aCornerList.Arc( arcIndex ) );
+                fmt::print( m_workFile, "{}", arcPath( arc.GetCenter(), arc.GetStartAngle(),
+                                                       arc.GetCentralAngle(), arc.GetRadius() ) );
+            }
+        }
+        else
+        {
+            const SEG& seg( aCornerList.Segment( ii ) );
+
+            VECTOR2D pos = userToDeviceCoordinates( seg.A );
+            fmt::println( m_workFile, "{:f} {:f} m", pos.x, pos.y );
+
+            pos = userToDeviceCoordinates( seg.B );
+            fmt::println( m_workFile, "{:f} {:f} l", pos.x, pos.y );
+        }
+    }
+
+    // Close path and stroke and/or fill
+    if( aFill == FILL_T::NO_FILL )
+        fmt::println( m_workFile, "S" );
+    else if( aWidth == 0 )
+        fmt::println( m_workFile, "f" );
+    else
+        fmt::println( m_workFile, "b" );
 }
 
 

include/plotters/plotter_gerber.h

@@ -60,9 +60,13 @@ public:
                               double aScale, bool aMirror ) override;
 
     // Basic plot primitives
+
+    // Note: do not use Rect() to plot rounded-corner rectangles.  Use PlotPolyAsRegion() instead.
     virtual void Rect( const VECTOR2I& p1, const VECTOR2I& p2, FILL_T fill, int width,
                        int aCornerRadius = 0 ) override;
+
     virtual void Circle( const VECTOR2I& pos, int diametre, FILL_T fill, int width ) override;
+
     virtual void Arc( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
                       const EDA_ANGLE& aAngle, double aRadius, FILL_T aFill, int aWidth ) override;
 

include/plotters/plotters_pslike.h

@@ -418,6 +418,9 @@ private:
     void drawOverbars( const std::vector<OverbarInfo>& aOverbars,
                        const EDA_ANGLE& aOrient, const KIFONT::METRICS& aFontMetrics );
 
+    std::string arcPath( const VECTOR2D& aCenter, const EDA_ANGLE& aStartAngle,
+                         const EDA_ANGLE& aAngle, double aRadius );
+
 public:
     virtual void PlotText( const VECTOR2I&        aPos,
                            const COLOR4D&         aColor,

pcbnew/plot_brditems_plotter.cpp

@@ -1099,18 +1099,18 @@ void BRDITEMS_PLOTTER::PlotShape( const PCB_SHAPE* aShape )
                 BOX2I box( aShape->GetStart(), VECTOR2I( aShape->GetEnd().x - aShape->GetStart().x,
                                                          aShape->GetEnd().y - aShape->GetStart().y ) );
                 box.Normalize();
+
+                if( margin < 0 )
+                {
+                    box.Inflate( margin );
+                    radius += margin;
+                }
+
                 SHAPE_RECT rect( box );
                 rect.SetRadius( radius );
 
                 SHAPE_LINE_CHAIN outline = rect.Outline();
-                SHAPE_POLY_SET  poly;
-                poly.NewOutline();
-
-                for( int ii = 0; ii < outline.PointCount(); ++ii )
-                    poly.Append( outline.CPoint( ii ) );
-
-                if( margin < 0 )
-                    poly.Inflate( margin / 2, CORNER_STRATEGY::ROUND_ALL_CORNERS, aShape->GetMaxError() );
+                SHAPE_POLY_SET  poly( outline );
 
                 FILL_T fill_mode = isSolidFill ? FILL_T::FILLED_SHAPE : FILL_T::NO_FILL;
 
@@ -1119,11 +1119,11 @@ void BRDITEMS_PLOTTER::PlotShape( const PCB_SHAPE* aShape )
                     if( m_plotter->GetPlotterType() == PLOT_FORMAT::GERBER )
                     {
                         GERBER_PLOTTER* gbr_plotter = static_cast<GERBER_PLOTTER*>( m_plotter );
-                        gbr_plotter->PlotPolyAsRegion( poly.COutline( 0 ), fill_mode, thickness,
-                                                       &gbr_metadata );
+                        gbr_plotter->PlotPolyAsRegion( poly.COutline( 0 ), fill_mode, thickness, &gbr_metadata );
                     }
                     else
                     {
+                        // TODO: PlotPoly needs to handle arcs...
                         m_plotter->PlotPoly( poly.COutline( 0 ), fill_mode, thickness, getMetadata() );
                     }
                 }