update issues with gradients fixed

playground/gradients/main.cpp

@@ -94,8 +94,8 @@ class GradientBox: public QWidget
         m_qskBox = new BoxQsk();
 
         auto layout = new QHBoxLayout( this );
-        layout->addWidget( m_qskBox );
         layout->addWidget( m_qtBox );
+        layout->addWidget( m_qskBox );
 
         showGradient( { Qt::green, Qt::red, Qt::yellow, Qt::cyan, Qt::darkCyan } );
     }
@@ -116,7 +116,8 @@ class GradientBox: public QWidget
             stops += { ( i + 1 ) * step, colors[i] };
         }
 
-        QLinearGradient gradient( 0.0, 0.0, 0.0, 1.0 );
+        QLinearGradient gradient( 0.0, 0.0, 0.5, 0.5 );
+        gradient.setSpread( QGradient::ReflectSpread );
         gradient.setStops( stops );
 
         showGradient( gradient );

src/nodes/QskBoxFillNode.cpp

@@ -50,9 +50,18 @@ class QskBoxFillNodePrivate final : public QSGGeometryNodePrivate
     {
     }
 
-    QskHashValue metricsHash = 0;
+    inline void resetValues()
+    {
+        rect = QRectF();
+        gradientHash = 0;
+        metricsHash = 0;
+    }
+
     QRectF rect;
 
+    QskHashValue gradientHash = 0;
+    QskHashValue metricsHash = 0;
+
     QSGGeometry geometry;
     int gradientType = -1;
 };
@@ -75,26 +84,31 @@ void QskBoxFillNode::updateNode(
 
     if ( rect.isEmpty() || !gradient.isVisible() )
     {
-        d->rect = QRectF();
+        d->resetValues();
-        d->metricsHash = 0;
         QskSGNode::resetGeometry( this );
 
         return;
     }
 
     const auto metricsHash = qskMetricsHash( shapeMetrics, borderMetrics );
-    const bool dirtyGeometry = ( metricsHash != d->metricsHash ) || ( rect != d->rect );
+    const auto gradientHash = gradient.hash( 22879 );
+
+    const bool dirtyColors = gradientHash != d->gradientHash;
+    const bool dirtyMetrics = ( metricsHash != d->metricsHash ) || ( rect != d->rect );
 
     d->metricsHash = metricsHash;
+    d->gradientHash = gradientHash;
     d->rect = rect;
 
-    if ( dirtyGeometry )
+    if ( dirtyMetrics )
     {
         QskBoxRenderer::renderFill( rect, shapeMetrics, borderMetrics, d->geometry );
         markDirty( QSGNode::DirtyGeometry );
     }
 
     if ( gradient.isMonochrome() )
+    {
+        if ( dirtyColors )
         {
             if ( material() == nullptr || d->gradientType >= 0 )
             {
@@ -111,7 +125,12 @@ void QskBoxFillNode::updateNode(
                 markDirty( QSGNode::DirtyMaterial );
             }
         }
+    }
     else
+    {
+        // dirtyMetrics: the shader also depends on the target rectangle !
+
+        if ( dirtyColors || dirtyMetrics )
         {
             const auto effectiveGradient = qskEffectiveGradient( gradient );
             const auto gradientType = effectiveGradient.type();
@@ -127,3 +146,4 @@ void QskBoxFillNode::updateNode(
                 markDirty( QSGNode::DirtyMaterial );
         }
     }
+}

src/nodes/QskBoxRenderer.cpp

@@ -43,32 +43,33 @@ void QskBoxRenderer::renderBox( const QRectF& rect,
 bool QskBoxRenderer::isGradientSupported(
     const QskBoxShapeMetrics&, const QskGradient& gradient )
 {
-    if ( !gradient.isVisible() || gradient.isMonochrome() )
+    if ( !gradient.isVisible() || gradient.isMonochrome()
+        || ( gradient.type() == QskGradient::Stops ) )
+    {
         return true;
+    }
 
-    switch( gradient.type() )
+    if ( gradient.type() == QskGradient::Linear )
     {
-        case QskGradient::Linear:
+        const auto dir = gradient.linearDirection();
-        {
-            auto dir = gradient.linearDirection();
 
         if ( dir.isTilted() )
         {
-                // only diagonal from topLeft to bottomRight
+            if ( dir.x1() == 0.0 && dir.y1() == 0.0
-                return ( dir.x1() == 0.0 ) && ( dir.y1() == 0.0 )
+                && dir.x2() == 1.0 && dir.y2() == 1.0 )
-                    && ( dir.x2() == 1.0 ) && ( dir.y2() == 1.0 );
+            {
+                return true;
+            }
+        }
+        else
+        {
+            if ( dir.x1() == 0.0 && dir.x2() == 1.0 )
+                return true;
+
+            if ( dir.y1() == 0.0 && dir.y2() == 1.0 )
+                return true;
+        }
     }
 
-            return true;
-        }
-        case QskGradient::Radial:
-        case QskGradient::Conic:
-        {
     return false;
 }
-        default:
-        {
-            return true;
-        }
-    }
-}

src/nodes/QskGradientMaterial.cpp

@@ -180,6 +180,12 @@ namespace
                 changed = true;
             }
 
+            /*
+                When having a gradient, that does not need spreading
+                we could set QskGradient::PadSpread to potentally reduce
+                the number of color ramps. TODO ...
+             */
+
             if ( gradient.spread() != spread() )
             {
                 setSpread( gradient.spread() );

src/nodes/QskRectangleNode.cpp

@@ -188,7 +188,8 @@ void QskRectangleNode::updateNode(
             markDirty( QSGNode::DirtyGeometry );
         }
 
-        if ( dirtyColors )
+        // dirtyMetrics: the shader also depends on the target rectangle !
+        if ( dirtyColors || dirtyMetrics )
         {
             const auto gradientType = effectiveGradient.type();