Plotters: add plot Arcs using EDA_SHAPE or center, start point and end point.

It avoid trying to calculate arc angles (start, end or arc angle) that
frequently create issues due to reverse Y axis, plot mirrored and/or
angle normalization with different criteria.
Fixes #10914
https://gitlab.com/kicad/code/kicad/issues/10914

common/plotters/DXF_plotter.cpp

@@ -5,7 +5,7 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2017-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2017-2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License

common/plotters/GERBER_plotter.cpp

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2019 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -1124,9 +1124,9 @@ void GERBER_PLOTTER::ThickSegment( const VECTOR2I& start, const VECTOR2I& end, i
     }
 }
 
-void GERBER_PLOTTER::ThickArc( const VECTOR2I& centre, const EDA_ANGLE& aStartAngle,
+void GERBER_PLOTTER::ThickArc( const VECTOR2I& aCentre, const EDA_ANGLE& aStartAngle,
                                const EDA_ANGLE& aEndAngle, int aRadius, int aWidth,
-                               OUTLINE_MODE tracemode, void* aData )
+                               OUTLINE_MODE aTraceMode, void* aData )
 {
     GBR_METADATA *gbr_metadata = static_cast<GBR_METADATA*>( aData );
     SetCurrentLineWidth( aWidth, gbr_metadata );
@@ -1134,21 +1134,59 @@ void GERBER_PLOTTER::ThickArc( const VECTOR2I& centre, const EDA_ANGLE& aStartAn
     if( gbr_metadata )
         formatNetAttribute( &gbr_metadata->m_NetlistMetadata );
 
-    if( tracemode == FILLED )
+    if( aTraceMode == FILLED )
     {
-        Arc( centre, aStartAngle, aEndAngle, aRadius, FILL_T::NO_FILL, DO_NOT_SET_LINE_WIDTH );
+        Arc( aCentre, aStartAngle, aEndAngle, aRadius, FILL_T::NO_FILL, DO_NOT_SET_LINE_WIDTH );
     }
     else
     {
         SetCurrentLineWidth( USE_DEFAULT_LINE_WIDTH );
-        Arc( centre, aStartAngle, aEndAngle, aRadius - ( aWidth - m_currentPenWidth ) / 2,
+        Arc( aCentre, aStartAngle, aEndAngle, aRadius - ( aWidth - m_currentPenWidth ) / 2,
              FILL_T::NO_FILL, DO_NOT_SET_LINE_WIDTH );
-        Arc( centre, aStartAngle, aEndAngle, aRadius + ( aWidth - m_currentPenWidth ) / 2,
+        Arc( aCentre, aStartAngle, aEndAngle, aRadius + ( aWidth - m_currentPenWidth ) / 2,
              FILL_T::NO_FILL, DO_NOT_SET_LINE_WIDTH );
     }
 }
 
 
+void GERBER_PLOTTER::ThickArc( const VECTOR2I& aCentre, const VECTOR2I& aStart,
+                               const VECTOR2I& aEnd, int aWidth,
+                               OUTLINE_MODE aTraceMode, void* aData )
+{
+    EDA_ANGLE start_angle( aStart - aCentre );
+    EDA_ANGLE end_angle( aEnd - aCentre );
+
+    if( start_angle > end_angle )
+    {
+        if( end_angle < ANGLE_0 )
+            end_angle.Normalize();
+        else
+            start_angle = start_angle.Normalize() - ANGLE_360;
+    }
+
+    int radius = (aStart - aCentre).EuclideanNorm();
+
+    if( !m_yaxisReversed )   // should be always the case
+    {
+        std::swap( end_angle, start_angle );
+        end_angle = -end_angle;
+        start_angle = -start_angle;
+    }
+
+    ThickArc( aCentre, start_angle, end_angle, radius, aWidth, aTraceMode, aData );
+}
+
+
+void GERBER_PLOTTER::ThickArc( const EDA_SHAPE& aArcShape,
+                           OUTLINE_MODE aTraceMode, void* aData )
+{
+    wxASSERT( aArcShape.GetShape() == SHAPE_T::ARC );
+
+    ThickArc( aArcShape.getCenter(), aArcShape.GetStart(), aArcShape.GetEnd(),
+              aArcShape.GetWidth(), aTraceMode, aData );
+}
+
+
 void GERBER_PLOTTER::ThickRect( const VECTOR2I& p1, const VECTOR2I& p2, int width,
                             OUTLINE_MODE tracemode, void* aData )
 {

common/plotters/HPGL_plotter.cpp

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2017 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 2020-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2020-2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -570,8 +570,6 @@ void HPGL_PLOTTER::ThickSegment( const VECTOR2I& start, const VECTOR2I& end,
 void HPGL_PLOTTER::Arc( const VECTOR2I& aCenter, const EDA_ANGLE& aStartAngle,
                         const EDA_ANGLE& aEndAngle, int aRadius, FILL_T aFill, int aWidth )
 {
-    wxASSERT( m_outputFile );
-
     if( aRadius <= 0 )
         return;
 
@@ -611,6 +609,18 @@ void HPGL_PLOTTER::Arc( const VECTOR2I& aCenter, const EDA_ANGLE& aStartAngle,
 }
 
 
+void HPGL_PLOTTER::Arc( const VECTOR2I& aCenter, const VECTOR2I& aStart,
+                        const VECTOR2I& aEnd,
+                        FILL_T aFill, int aWidth, int aMaxError )
+{
+    EDA_ANGLE startAngle( aStart - aCenter );
+    EDA_ANGLE endAngle( aEnd - aCenter );
+    int       radius = ( aStart - aCenter ).EuclideanNorm();
+
+    Arc( aCenter, -endAngle, -startAngle, radius, aFill, aWidth );
+}
+
+
 void HPGL_PLOTTER::FlashPadOval( const VECTOR2I& aPos, const VECTOR2I& aSize,
                                  const EDA_ANGLE& aOrient, OUTLINE_MODE aTraceMode, void* aData )
 {

common/plotters/plotter.cpp

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2017 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 2017-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2017-2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -159,6 +159,9 @@ void PLOTTER::Arc( const VECTOR2I& aCenter, const VECTOR2I& aStart, const VECTOR
     EDA_ANGLE startAngle( aStart - aCenter );
     EDA_ANGLE endAngle( aEnd - aCenter );
     int       radius = ( aStart - aCenter ).EuclideanNorm();
+
+    #if 0
+    // Approximate arc by segments:
     int       numSegs = GetArcToSegmentCount( radius, aMaxError, FULL_CIRCLE );
     EDA_ANGLE delta = ANGLE_360 / std::max( 8, numSegs );
     VECTOR2I  start( aStart );
@@ -193,6 +196,25 @@ void PLOTTER::Arc( const VECTOR2I& aCenter, const VECTOR2I& aStart, const VECTOR
         LineTo( end );
         FinishTo( aCenter );
     }
+
+    #else
+    if( startAngle > endAngle )
+    {
+        if( endAngle < ANGLE_0 )
+            endAngle.Normalize();
+        else
+            startAngle = startAngle.Normalize() - ANGLE_360;
+    }
+
+    if( m_yaxisReversed )
+    {
+        std::swap( startAngle, endAngle );
+        startAngle = -startAngle;
+        endAngle = -endAngle;
+    }
+
+    Arc( aCenter, startAngle, endAngle, radius, aFill, aWidth );
+    #endif
 }
 
 
@@ -607,6 +629,42 @@ void PLOTTER::ThickArc( const VECTOR2I& centre, const EDA_ANGLE& aStartAngle,
 }
 
 
+void PLOTTER::ThickArc( const VECTOR2I& aCentre, const VECTOR2I& aStart,
+                        const VECTOR2I& aEnd, int aWidth,
+                        OUTLINE_MODE aTraceMode, void* aData )
+{
+    if( aTraceMode == FILLED )
+    {
+        Arc( aCentre, aStart, aEnd, FILL_T::NO_FILL, aWidth, GetPlotterArcHighDef() );
+    }
+    else
+    {
+        SetCurrentLineWidth( -1 );
+        int radius = ( aStart - aCentre ).EuclideanNorm();
+
+        int new_radius = radius - ( aWidth - m_currentPenWidth ) / 2;
+        VECTOR2I start = ( aStart - aCentre ).Resize( new_radius ) + aCentre;
+        VECTOR2I end = ( aEnd - aCentre ).Resize( new_radius ) + aCentre;
+
+        Arc( aCentre, start, end, FILL_T::NO_FILL, -1, GetPlotterArcHighDef() );
+
+        new_radius = radius + ( aWidth - m_currentPenWidth ) / 2;
+        start = ( aStart - aCentre ).Resize( new_radius ) + aCentre;
+        end = ( aEnd - aCentre ).Resize( new_radius ) + aCentre;
+
+        Arc( aCentre, start, end, FILL_T::NO_FILL, -1, GetPlotterArcHighDef() );
+    }
+}
+
+
+void PLOTTER::ThickArc( const EDA_SHAPE& aArcShape,
+                           OUTLINE_MODE aTraceMode, void* aData )
+{
+    ThickArc( aArcShape.getCenter(),aArcShape.GetStart(), aArcShape.GetEnd(),
+              aArcShape.GetWidth(), aTraceMode, aData );
+}
+
+
 void PLOTTER::ThickRect( const VECTOR2I& p1, const VECTOR2I& p2, int width,
                          OUTLINE_MODE tracemode, void* aData )
 {

include/plotters/plotter.h

@@ -309,13 +309,24 @@ public:
     // Higher level primitives -- can be drawn as line, sketch or 'filled'
     virtual void ThickSegment( const VECTOR2I& start, const VECTOR2I& end, int width,
                                OUTLINE_MODE tracemode, void* aData );
-    virtual void ThickArc( const VECTOR2I& centre, const EDA_ANGLE& StAngle,
+
-                           const EDA_ANGLE& EndAngle, int rayon, int width,
+    virtual void ThickArc( const VECTOR2I& aCentre, const EDA_ANGLE& StAngle,
-                           OUTLINE_MODE tracemode, void* aData );
+                           const EDA_ANGLE& EndAngle, int aRadius, int aWidth,
+                           OUTLINE_MODE aTraceMode, void* aData );
+
+    virtual void ThickArc( const VECTOR2I& aCentre, const VECTOR2I& aStart,
+                           const VECTOR2I& aEnd, int aWidth,
+                           OUTLINE_MODE aTraceMode, void* aData );
+
+    virtual void ThickArc( const EDA_SHAPE& aArcShape,
+                           OUTLINE_MODE aTraceMode, void* aData );
+
     virtual void ThickRect( const VECTOR2I& p1, const VECTOR2I& p2, int width, OUTLINE_MODE tracemode,
                             void* aData );
+
     virtual void ThickCircle( const VECTOR2I& pos, int diametre, int width, OUTLINE_MODE tracemode,
                               void* aData );
+
     virtual void FilledCircle( const VECTOR2I& pos, int diametre, OUTLINE_MODE tracemode,
                                void* aData );
 

include/plotters/plotter_gerber.h

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2020 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 2016-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2016-2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -77,13 +77,23 @@ public:
     virtual void ThickSegment( const VECTOR2I& start, const VECTOR2I& end, int width,
                                OUTLINE_MODE tracemode, void* aData ) override;
 
-    virtual void ThickArc( const VECTOR2I& centre, const EDA_ANGLE& aStartAngle,
+    virtual void ThickArc( const VECTOR2I& aCentre, const EDA_ANGLE& aStartAngle,
                            const EDA_ANGLE& aEndAngle, int aRadius, int aWidth,
-                           OUTLINE_MODE tracemode, void* aData ) override;
+                           OUTLINE_MODE aTraceMode, void* aData ) override;
+
+    virtual void ThickArc( const VECTOR2I& aCentre, const VECTOR2I& aStart,
+                           const VECTOR2I& aEnd, int aWidth,
+                           OUTLINE_MODE aTraceMode, void* aData ) override;
+
+    virtual void ThickArc( const EDA_SHAPE& aArcShape,
+                           OUTLINE_MODE aTraceMode, void* aData ) override;
+
     virtual void ThickRect( const VECTOR2I& p1, const VECTOR2I& p2, int width,
                             OUTLINE_MODE tracemode, void* aData ) override;
+
     virtual void ThickCircle( const VECTOR2I& pos, int diametre, int width,
                               OUTLINE_MODE tracemode, void* aData ) override;
+
     virtual void FilledCircle( const VECTOR2I& pos, int diametre,
                               OUTLINE_MODE tracemode, void* aData ) override;
 

include/plotters/plotter_hpgl.h

@@ -1,7 +1,7 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2016-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2016-2022 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -121,7 +121,12 @@ public:
     virtual void Arc( const VECTOR2I& aCenter, const EDA_ANGLE& aStartAngle,
                       const EDA_ANGLE& aEndAngle, int aRadius, FILL_T aFill,
                       int aWidth = USE_DEFAULT_LINE_WIDTH ) override;
+
+    virtual void Arc( const VECTOR2I& aCenter, const VECTOR2I& aStart, const VECTOR2I& aEnd,
+                      FILL_T aFill, int aWidth, int aMaxError ) override;
+
     virtual void PenTo( const VECTOR2I& pos, char plume ) override;
+
     virtual void FlashPadCircle( const VECTOR2I& aPadPos, int aDiameter,
                                  OUTLINE_MODE aTraceMode, void* aData ) override;
     virtual void FlashPadOval( const VECTOR2I& aPadPos, const VECTOR2I& aSize,

pcbnew/plot_board_layers.cpp

@@ -579,13 +579,14 @@ void PlotStandardLayer( BOARD* aBoard, PLOTTER* aPlotter, LSET aLayerMask,
         if( track->Type() == PCB_ARC_T )
         {
             const     PCB_ARC* arc = static_cast<const PCB_ARC*>( track );
-            VECTOR2D  center( arc->GetCenter() );
+            PCB_SHAPE arc_shape( nullptr, SHAPE_T::ARC );
-            int       radius = arc->GetRadius();
+            arc_shape.SetWidth( width );
-            EDA_ANGLE start_angle = arc->GetArcAngleStart();
+            arc_shape.SetStart( arc->GetStart() );
-            EDA_ANGLE end_angle = start_angle + arc->GetAngle();
+            arc_shape.SetEnd( arc->GetEnd() );
+            arc_shape.SetCenter( arc->GetCenter() );
 
-            aPlotter->ThickArc( center, -end_angle, -start_angle, radius, width, plotMode,
+            aPlotter->ThickArc( arc->GetCenter(), arc->GetStart(), arc->GetEnd(),
-                                &gbr_metadata );
+                                width, plotMode, &gbr_metadata );
         }
         else
         {

pcbnew/plot_brditems_plotter.cpp

@@ -673,10 +673,9 @@ void BRDITEMS_PLOTTER::PlotFootprintShape( const FP_SHAPE* aShape )
         case SHAPE_T::ARC:
         {
             radius = KiROUND( GetLineLength( aShape->GetCenter(), aShape->GetStart() ) );
-            EDA_ANGLE startAngle( aShape->GetStart() - aShape->GetCenter() );
-            EDA_ANGLE endAngle = startAngle - aShape->GetArcAngle();
 
             // when startAngle == endAngle ThickArc() doesn't know whether it's 0 deg and 360 deg
+            // but it is a circle
             if( std::abs( aShape->GetArcAngle().AsDegrees() ) == 360.0 )
             {
                 m_plotter->ThickCircle( aShape->GetCenter(), radius * 2, thickness, GetPlotMode(),
@@ -684,8 +683,7 @@ void BRDITEMS_PLOTTER::PlotFootprintShape( const FP_SHAPE* aShape )
             }
             else
             {
-                m_plotter->ThickArc( aShape->GetCenter(), -startAngle, -endAngle, radius,
+                m_plotter->ThickArc( *aShape, GetPlotMode(), &gbr_metadata );
-                                     thickness, GetPlotMode(), &gbr_metadata );
             }
         }
             break;
@@ -945,10 +943,8 @@ void BRDITEMS_PLOTTER::PlotPcbShape( const PCB_SHAPE* aShape )
 
         case SHAPE_T::ARC:
         {
-            EDA_ANGLE startAngle( aShape->GetStart() - aShape->GetCenter() );
-            EDA_ANGLE endAngle = startAngle - aShape->GetArcAngle();
-
             // when startAngle == endAngle ThickArc() doesn't know whether it's 0 deg and 360 deg
+            // but it is a circle
             if( std::abs( aShape->GetArcAngle().AsDegrees() ) == 360.0 )
             {
                 m_plotter->ThickCircle( aShape->GetCenter(), aShape->GetRadius() * 2, thickness,
@@ -956,8 +952,7 @@ void BRDITEMS_PLOTTER::PlotPcbShape( const PCB_SHAPE* aShape )
             }
             else
             {
-                m_plotter->ThickArc( aShape->GetCenter(), -startAngle, -endAngle,
+                m_plotter->ThickArc( *aShape, GetPlotMode(), &gbr_metadata );
-                                     aShape->GetRadius(), thickness, GetPlotMode(), &gbr_metadata );
             }
 
             break;