diff --git a/src/common/QskRgbValue.h b/src/common/QskRgbValue.h
index 163aefd4..f15678ff 100644
--- a/src/common/QskRgbValue.h
+++ b/src/common/QskRgbValue.h
@@ -209,6 +209,16 @@ namespace QskRgb
         return toTransparent( rgb, qRound( opacity * 255 ) );
     }
 
+    inline bool isVisible( QRgb rgb )
+    {
+        return qAlpha( rgb ) > 0;
+    }
+
+    inline bool isVisible( const QColor& color )
+    {
+        return color.isValid() && color.alpha() > 0;
+    }
+
     QSK_EXPORT QRgb lighter( QRgb, int factor = 150 ) noexcept;
     QSK_EXPORT QRgb darker( QRgb, int factor = 200 ) noexcept;
 }
diff --git a/src/nodes/QskArcNode.cpp b/src/nodes/QskArcNode.cpp
index d8328bd7..39946983 100644
--- a/src/nodes/QskArcNode.cpp
+++ b/src/nodes/QskArcNode.cpp
@@ -12,6 +12,7 @@
 #include "QskGradient.h"
 #include "QskSGNode.h"
 #include "QskShadowMetrics.h"
+#include "QskRgbValue.h"
 
 #include <qpainterpath.h>
 
@@ -91,12 +92,10 @@ void QskArcNode::setArcData( const QRectF& rect, const QskArcMetrics& arcMetrics
         const auto metricsArc = arcMetrics.toAbsolute( rect.size() );
 
         const auto hasFilling = gradient.isVisible();
-        const auto hasBorder = ( borderWidth > 0.0 )
-            && borderColor.isValid() && ( borderColor.alpha() > 0 );
+        const auto hasBorder = ( borderWidth > 0.0 ) && QskRgb::isVisible( borderColor );
+        const auto hasShadow = hasFilling && QskRgb::isVisible( shadowColor );
 
-        const auto hasShadow = shadowColor.isValid() && ( shadowColor.alpha() > 0 );
-
-        if ( hasShadow && hasFilling )
+        if ( hasShadow )
         {
             /*
                 The shader of the shadow node is for circular arcs and we have some
diff --git a/src/nodes/QskArcRenderNode.cpp b/src/nodes/QskArcRenderNode.cpp
index 4da98336..2abacb58 100644
--- a/src/nodes/QskArcRenderNode.cpp
+++ b/src/nodes/QskArcRenderNode.cpp
@@ -9,11 +9,12 @@
 #include "QskArcMetrics.h"
 #include "QskGradient.h"
 #include "QskSGNode.h"
+#include "QskRgbValue.h"
 #include "QskFillNodePrivate.h"
 
 static inline bool qskHasBorder( qreal width, const QColor& color )
 {
-    return ( width > 0.0 ) && color.isValid() && ( color.alpha() > 0 );
+    return ( width > 0.0 ) && QskRgb::isVisible( color );
 }
 
 class QskArcRenderNodePrivate final : public QskFillNodePrivate
@@ -42,7 +43,7 @@ class QskArcRenderNodePrivate final : public QskFillNodePrivate
     {
         QskHashValue hash = 13000;
 
-        if ( borderColor.isValid() && ( borderColor.alpha() > 0 ) )
+        if ( QskRgb::isVisible( borderColor ) )
             hash = qHashBits( &borderColor, sizeof( borderColor ), hash );
 
         if ( gradient.isVisible() )
diff --git a/src/nodes/QskArcRenderer.cpp b/src/nodes/QskArcRenderer.cpp
index 7569939d..48cd0f0e 100644
--- a/src/nodes/QskArcRenderer.cpp
+++ b/src/nodes/QskArcRenderer.cpp
@@ -489,7 +489,7 @@ void QskArcRenderer::setColoredBorderLines( const QRectF& rect,
     geometry.setDrawingMode( QSGGeometry::DrawTriangleStrip );
     geometry.markVertexDataDirty();
 
-    if ( borderWidth <= 0.0 || !( borderColor.isValid() && borderColor.alpha() > 0 ) )
+    if ( borderWidth <= 0.0 || !QskRgb::isVisible( borderColor ) )
     {
         qskAllocateColoredLines( geometry, 0 );
         return;
diff --git a/src/nodes/QskBoxNode.cpp b/src/nodes/QskBoxNode.cpp
index a4ea7f74..4eebfeb1 100644
--- a/src/nodes/QskBoxNode.cpp
+++ b/src/nodes/QskBoxNode.cpp
@@ -13,6 +13,7 @@
 #include "QskShadowMetrics.h"
 #include "QskBoxBorderMetrics.h"
 #include "QskBoxBorderColors.h"
+#include "QskRgbValue.h"
 
 namespace
 {
@@ -69,8 +70,10 @@ void QskBoxNode::updateNode( const QRectF& rect,
 
     if ( !rect.isEmpty() )
     {
-        if ( !shadowMetrics.isNull()
-            && shadowColor.isValid() && shadowColor.alpha() != 0 )
+        const auto hasShadow = !shadowMetrics.isNull()
+            && QskRgb::isVisible( shadowColor );
+
+        if ( hasShadow )
         {
             shadowNode = qskNode< QskBoxShadowNode >( this, ShadowRole );
             shadowNode->setShadowData( shadowMetrics.shadowRect( rect ),
diff --git a/src/nodes/QskLinesNode.cpp b/src/nodes/QskLinesNode.cpp
index e3dc1671..cd1cacba 100644
--- a/src/nodes/QskLinesNode.cpp
+++ b/src/nodes/QskLinesNode.cpp
@@ -8,6 +8,7 @@
 #include "QskStippleMetrics.h"
 #include "QskStippledLineRenderer.h"
 #include "QskSGNode.h"
+#include "QskRgbValue.h"
 
 #include <qtransform.h>
 #include <qline.h>
@@ -163,8 +164,7 @@ void QskLinesNode::updateLines( const QColor& color,
     qreal lineWidth, const QskStippleMetrics& stippleMetrics,
     const QTransform& transform, int count, const QLineF* lines )
 {
-    if ( !stippleMetrics.isValid() || !color.isValid()
-        || color.alpha() == 0 || count == 0 )
+    if ( !stippleMetrics.isValid() || !QskRgb::isVisible( color ) || count == 0 )
     {
         QskSGNode::resetGeometry( this );
         return;
@@ -195,7 +195,7 @@ void QskLinesNode::updateGrid( const QColor& color,
     const QTransform& transform, const QRectF& rect,
     const QVector< qreal >& xValues, const QVector< qreal >& yValues )
 {
-    if ( !stippleMetrics.isValid() || !color.isValid() || color.alpha() == 0 )
+    if ( !stippleMetrics.isValid() || !QskRgb::isVisible( color ) )
     {
         QskSGNode::resetGeometry( this );
         return;
@@ -409,7 +409,7 @@ QSGGeometry::Point2D* QskLinesNode::setSolidLines(
 void QskLinesNode::updatePolygon( const QColor& color, qreal lineWidth,
     const QTransform& transform, const QPolygonF& polygon )
 {
-    if ( polygon.isEmpty() || !color.isValid() || ( color.alpha() == 0 ) )
+    if ( polygon.isEmpty() || !QskRgb::isVisible( color ) )
     {
         QskSGNode::resetGeometry( this );
         return;
diff --git a/src/nodes/QskStrokeNode.cpp b/src/nodes/QskStrokeNode.cpp
index fb16c63c..6d1625f7 100644
--- a/src/nodes/QskStrokeNode.cpp
+++ b/src/nodes/QskStrokeNode.cpp
@@ -6,6 +6,7 @@
 #include "QskStrokeNode.h"
 #include "QskVertex.h"
 #include "QskGradient.h"
+#include "QskRgbValue.h"
 
 #include <qpainterpath.h>
 
@@ -24,7 +25,7 @@ static inline bool qskIsPenVisible( const QPen& pen )
     }
     else
     {
-        if ( !pen.color().isValid() || ( pen.color().alpha() == 0 ) )
+        if ( !QskRgb::isVisible( pen.color() ) )
             return false;
     }