From 38130ffb7bcf35d99c5b762ab699b5b8e58e2170 Mon Sep 17 00:00:00 2001
From: Uwe Rathmann <Uwe.Rathmann@tigertal.de>
Date: Tue, 23 Jul 2024 18:06:25 +0200
Subject: [PATCH] some implementation for the closing ends of the borders in
 radial mode added

---
 src/nodes/QskArcNode.cpp     | 23 +++++++++++++++++----
 src/nodes/QskArcRenderer.cpp | 39 ++++++++++++++++++------------------
 2 files changed, 38 insertions(+), 24 deletions(-)

diff --git a/src/nodes/QskArcNode.cpp b/src/nodes/QskArcNode.cpp
index dcb5fd3b..34a91c52 100644
--- a/src/nodes/QskArcNode.cpp
+++ b/src/nodes/QskArcNode.cpp
@@ -200,11 +200,26 @@ void QskArcNode::setArcData( const QRectF& rect, const QskArcMetrics& arcMetrics
         borderNode->updateNode( rect, metricsArc, radial,
             borderWidth, borderColor, QskGradient() );
 #else
-        QPen pen( borderColor, borderWidth );
-        pen.setCapStyle( Qt::FlatCap );
+        {
+            /*
+                Qt centers the border over the boundaries, while we
+                always want to have the complete borders inside.
+                So we have to subtract 0.5 * border.
+             */
+                
+            QPen pen( borderColor, borderWidth );
+            pen.setCapStyle( Qt::SquareCap );
+            pen.setJoinStyle( Qt::MiterJoin );
 
-        const auto path = metricsArc.painterPath( rect, radial );
-        borderNode->updateNode( path, QTransform(), pen );
+            const auto b2 = 0.5 * borderWidth;
+            const auto r = rect.adjusted( b2, b2, -b2, -b2 ); 
+
+            const auto m = QskArcMetrics( metricsArc.startAngle(), metricsArc.spanAngle(),
+                metricsArc.thickness() - borderWidth );
+
+            const auto path = m.painterPath( r, radial );
+            borderNode->updateNode( path, QTransform(), pen );
+        }
 #endif
     }
     else
diff --git a/src/nodes/QskArcRenderer.cpp b/src/nodes/QskArcRenderer.cpp
index eac848a6..0acf432f 100644
--- a/src/nodes/QskArcRenderer.cpp
+++ b/src/nodes/QskArcRenderer.cpp
@@ -144,15 +144,16 @@ namespace
     {
       public:
         RadialStroker( const QRectF& rect, qreal thickness, qreal border )
-            : m_inner( thickness - 2 * border )
+            : m_sx( qMax( rect.width() / rect.height(), 1.0 ) )
+            , m_sy( qMax( rect.height() / rect.width(), 1.0 ) )
             , m_rx1( 0.5 * rect.width() )
             , m_ry1( 0.5 * rect.height() )
-            , m_rx2( m_rx1 - border )
-            , m_ry2( m_ry1 - border )
-            , m_rx3( m_rx2 - ( ( m_rx1 > m_ry1 ) ? m_inner * m_rx1 / m_ry1 : m_inner ) )
-            , m_ry3( m_ry2 - ( ( m_rx1 < m_ry1 ) ? m_inner * m_ry1 / m_rx1 : m_inner ) )
-            , m_rx4( m_rx3 - border )
-            , m_ry4( m_ry3 - border )
+            , m_rx2( m_rx1 - m_sx * border )
+            , m_ry2( m_ry1 - m_sy * border )
+            , m_rx3( m_rx1 - m_sx * ( thickness - border ) )
+            , m_ry3( m_ry1 - m_sy * ( thickness - border ) )
+            , m_rx4( m_rx1 - m_sx * thickness )
+            , m_ry4( m_ry1 - m_sy * thickness )
             , m_cx( rect.x() + m_rx1 )
             , m_cy( rect.y() + m_ry1 )
         {
@@ -178,30 +179,28 @@ namespace
             outer.setLine( m_cx + m_rx1 * cos, m_cy - m_ry1 * sin,
                 m_cx + m_rx2 * cos, m_cy - m_ry2 * sin, color );
 
-            inner.setLine( m_cx + m_rx3 * cos, m_cy - m_ry3 * sin,
-                m_cx + m_rx4 * cos, m_cy - m_ry4 * sin, color );
+            inner.setLine( m_cx + m_rx4 * cos, m_cy - m_ry4 * sin,
+                m_cx + m_rx3 * cos, m_cy - m_ry3 * sin, color );
         }
 
         inline void setClosingBorderLines( const QSGGeometry::ColoredPoint2D& pos,
             QskVertex::ColoredLine* lines, qreal sign, const QskVertex::Color color ) const
         {
-            // TODO ...
-#if 1
-            Q_UNUSED( pos );
-            Q_UNUSED( sign );
-
+            // Good enough until it is decided if we want to keep the radial mode.
             const auto& l0 = lines[0];
-            const qreal dx = 0.0;
-            const qreal dy = 0.0;
 
-            lines[-3].setLine( l0.x1() + dx, l0.y1() - dy, l0.x1(), l0.y1(), color );
-            lines[-2].setLine( l0.x1() + dx, l0.y1() - dy, l0.x1(), l0.y1(), color );
+            const auto s = m_sx / m_sy;
+            const auto dx = sign * l0.dy() * s;
+            const auto dy = sign * l0.dx() / s;
+
+            lines[-3].setLine( pos.x, pos.y, pos.x, pos.y, color );
+            lines[-2].setLine( pos.x + dx, pos.y - dy, pos.x, pos.y, color );
             lines[-1].setLine( l0.x1() + dx, l0.y1() - dy, l0.x1(), l0.y1(), color );
-#endif
         }
 
       private:
-        const qreal m_inner;
+        // stretch factors of the ellipse
+        const qreal m_sx, m_sy;
 
         // radii: out->in
         const qreal m_rx1, m_ry1, m_rx2, m_ry2, m_rx3, m_ry3, m_rx4, m_ry4;