Fixup some issues in libkimath

* Perform floating-point computations when needed
* Specify to use the default equality operator

libs/kimath/include/geometry/shape_circle.h

@@ -54,6 +54,8 @@ public:
         return new SHAPE_CIRCLE( *this );
     }
 
+    SHAPE_CIRCLE& operator=( const SHAPE_CIRCLE& ) = default;
+
     const BOX2I BBox( int aClearance = 0 ) const override
     {
         const VECTOR2I rc( m_radius + aClearance, m_radius + aClearance );

libs/kimath/src/convert_basic_shapes_to_polygon.cpp

@@ -47,7 +47,7 @@ void TransformCircleToPolygon( SHAPE_LINE_CHAIN& aBuffer,
     int     delta = 3600 / numSegs;   // rotate angle in 0.1 degree
     double  correction = GetCircletoPolyCorrectionFactor( numSegs );
     int     radius = aRadius * correction;    // make segments outside the circles
-    double  halfstep = delta/2;    // the starting value for rot angles
+    double  halfstep = delta/2.0;    // the starting value for rot angles
 
     for( int ii = 0; ii < numSegs; ii++ )
     {
@@ -71,7 +71,7 @@ void TransformCircleToPolygon( SHAPE_POLY_SET& aCornerBuffer, wxPoint aCenter, i
     int     delta = 3600 / numSegs;   // rotate angle in 0.1 degree
     double  correction = GetCircletoPolyCorrectionFactor( numSegs );
     int     radius = aRadius * correction;    // make segments outside the circles
-    double  halfstep = delta/2;    // the starting value for rot angles
+    double  halfstep = delta/2.0;    // the starting value for rot angles
 
     aCornerBuffer.NewOutline();
 

libs/kimath/src/trigo.cpp

@@ -387,16 +387,16 @@ const VECTOR2I GetArcCenter( const VECTOR2I& aStart, const VECTOR2I& aMid, const
                       bSlope * ( aStart.x + aMid.x ) -
                       aSlope * ( aMid.x + aEnd.x ) ) / ( 2 * ( bSlope - aSlope ) );
 
-    center.x = KiROUND( Clamp<double>( double( std::numeric_limits<int>::min() / 2 ),
+    center.x = KiROUND( Clamp<double>( double( std::numeric_limits<int>::min() / 2.0 ),
                                        result,
-                                       double( std::numeric_limits<int>::max() / 2 ) ) );
+                                       double( std::numeric_limits<int>::max() / 2.0 ) ) );
 
     result = ( ( ( aStart.x + aMid.x ) / 2.0 - center.x ) / aSlope +
                  ( aStart.y + aMid.y ) / 2.0 );
 
-    center.y = KiROUND( Clamp<double>( double( std::numeric_limits<int>::min() / 2 ),
+    center.y = KiROUND( Clamp<double>( double( std::numeric_limits<int>::min() / 2.0 ),
                                        result,
-                                       double( std::numeric_limits<int>::max() / 2 ) ) );
+                                       double( std::numeric_limits<int>::max() / 2.0 ) ) );
 
     return center;
 }