Add dashed lines and circles to preview draw context.

common/preview_items/draw_context.cpp

@@ -1,7 +1,7 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2019 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 2019-2023 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
@@ -66,6 +66,24 @@ void DRAW_CONTEXT::DrawCircle( const VECTOR2I& aOrigin, double aRad, bool aDeEmp
 }
 
 
+void DRAW_CONTEXT::DrawCircleDashed( const VECTOR2I& aOrigin, double aRad, double aStepAngle,
+                                     double aFillAngle, bool aDeEmphasised )
+{
+    const COLOR4D& color = m_render_settings.GetLayerColor( m_currLayer );
+
+    m_gal.SetLineWidth( m_lineWidth );
+    m_gal.SetStrokeColor( deemphasise( color, aDeEmphasised ) );
+    m_gal.SetIsStroke( true );
+    m_gal.SetIsFill( false );
+
+    for( int i = 0; i < 360; i += aStepAngle )
+    {
+        m_gal.DrawArc( aOrigin, aRad, EDA_ANGLE( i, DEGREES_T ),
+                       EDA_ANGLE( i + aFillAngle, DEGREES_T ) );
+    }
+}
+
+
 void DRAW_CONTEXT::DrawLine( const VECTOR2I& aStart, const VECTOR2I& aEnd, bool aDeEmphasised )
 {
     COLOR4D strokeColor = m_render_settings.GetLayerColor( m_currLayer );
@@ -77,6 +95,28 @@ void DRAW_CONTEXT::DrawLine( const VECTOR2I& aStart, const VECTOR2I& aEnd, bool
 }
 
 
+void DRAW_CONTEXT::DrawLineDashed( const VECTOR2I& aStart, const VECTOR2I& aEnd, int aDashStep,
+                                   int aDashFill, bool aDeEmphasised )
+{
+    COLOR4D strokeColor = m_render_settings.GetLayerColor( m_currLayer );
+
+    m_gal.SetLineWidth( m_lineWidth );
+    m_gal.SetIsStroke( true );
+    m_gal.SetStrokeColor( deemphasise( strokeColor, aDeEmphasised ) );
+
+    VECTOR2I delta = aEnd - aStart;
+    int      vecLen = delta.EuclideanNorm();
+
+    for( int i = 0; i < vecLen; i += aDashStep )
+    {
+        VECTOR2I a = aStart + delta.Resize( i );
+        VECTOR2I b = aStart + delta.Resize( std::min( i + aDashFill, vecLen ) );
+
+        m_gal.DrawLine( a, b );
+    }
+}
+
+
 void DRAW_CONTEXT::DrawLineWithAngleHighlight( const VECTOR2I& aStart, const VECTOR2I& aEnd,
                                                bool aDeEmphasised )
 {

include/preview_items/draw_context.h

@@ -1,7 +1,7 @@
 /*
  * This program source code file is part of KICAD, a free EDA CAD application.
  *
- * Copyright (C) 2017 Kicad Developers, see change_log.txt for contributors.
+ * Copyright (C) 2017-2023 Kicad Developers, see change_log.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
@@ -55,6 +55,17 @@ namespace PREVIEW
          */
         void DrawCircle( const VECTOR2I& aOrigin, double aRad, bool aDeEmphasised );
 
+        /**
+         * Draw a dashed preview circle on the current layer
+         *
+         * @param aOrigin       circle origin
+         * @param aRad          circle radius
+         * @param aStepAngle    dash step angle
+         * @param aFillAngle    dash fill angle
+         * @param aDeEmphasised draw the circle de-emphasised
+         */
+        void DrawCircleDashed( const VECTOR2I& aOrigin, double aRad, double aStepAngle,
+                               double aFillAngle, bool aDeEmphasised );
 
         /**
          * Draw a simple line on the current layer.
@@ -65,6 +76,17 @@ namespace PREVIEW
          */
         void DrawLine( const VECTOR2I& aStart, const VECTOR2I& aEnd, bool aDeEmphasised );
 
+        /**
+         * Draw a dashed line on the current layer.
+         *
+         * @param aStart        line start point
+         * @param aEnd          line end point
+         * @param aDashStep     dash step distance
+         * @param aDashFill     dash fill distance
+         * @param aDeEmphasised draw the line de-emphasised
+         */
+        void DrawLineDashed( const VECTOR2I& aStart, const VECTOR2I& aEn, int aDashStep,
+                             int aDashFill, bool aDeEmphasised );
 
         /**
          * Draw a straight line on the current layer, with a special highlight when