Fix gradient fills using color ramps not respecting symbol transparency

nyalldawson · nyalldawson · commit a0c2c7aaad92 · 2014-03-21T19:47:26.000+11:00
diff --git a/python/core/symbology-ng/qgsvectorcolorrampv2.sip b/python/core/symbology-ng/qgsvectorcolorrampv2.sip
@@ -83,7 +83,7 @@ class QgsVectorGradientColorRampV2 : QgsVectorColorRampV2
 
     /**copy color ramp stops to a QGradient
     * @note added in 2.1 */
-    void addStopsToGradient( QGradient* gradient );
+    void addStopsToGradient( QGradient* gradient, double alpha = 1 );
 };
 
 class QgsVectorRandomColorRampV2 : QgsVectorColorRampV2
diff --git a/src/core/symbology-ng/qgsfillsymbollayerv2.cpp b/src/core/symbology-ng/qgsfillsymbollayerv2.cpp
@@ -678,7 +678,7 @@ void QgsGradientFillSymbolLayerV2::applyGradient( const QgsSymbolV2RenderContext
   {
     //color ramp gradient
     QgsVectorGradientColorRampV2* gradRamp = static_cast<QgsVectorGradientColorRampV2*>( gradientRamp );
-    gradRamp->addStopsToGradient( &gradient );
+    gradRamp->addStopsToGradient( &gradient, context.alpha() );
   }
   else
   {
diff --git a/src/core/symbology-ng/qgsvectorcolorrampv2.cpp b/src/core/symbology-ng/qgsvectorcolorrampv2.cpp
@@ -219,16 +219,28 @@ void QgsVectorGradientColorRampV2::convertToDiscrete( bool discrete )
   mDiscrete = discrete;
 }
 
-void QgsVectorGradientColorRampV2::addStopsToGradient( QGradient* gradient )
+void QgsVectorGradientColorRampV2::addStopsToGradient( QGradient* gradient, double alpha )
 {
   //copy color ramp stops to a QGradient
-  gradient->setColorAt( 0, mColor1 );
-  gradient->setColorAt( 1, mColor2 );
+  QColor color1 = mColor1;
+  QColor color2 = mColor2;
+  if ( alpha < 1 )
+  {
+    color1.setAlpha( color1.alpha() * alpha );
+    color2.setAlpha( color2.alpha() * alpha );
+  }
+  gradient->setColorAt( 0, color1 );
+  gradient->setColorAt( 1, color2 );
 
   for ( QgsGradientStopsList::const_iterator it = mStops.begin();
         it != mStops.end(); ++it )
   {
-    gradient->setColorAt( it->offset , it->color );
+    QColor rampColor = it->color;
+    if ( alpha < 1 )
+    {
+      rampColor.setAlpha( rampColor.alpha() * alpha );
+    }
+    gradient->setColorAt( it->offset , rampColor );
   }
 }
 
diff --git a/src/core/symbology-ng/qgsvectorcolorrampv2.h b/src/core/symbology-ng/qgsvectorcolorrampv2.h
@@ -94,7 +94,7 @@ class CORE_EXPORT QgsVectorGradientColorRampV2 : public QgsVectorColorRampV2
 
     /**copy color ramp stops to a QGradient
     * @note added in 2.1 */
-    void addStopsToGradient( QGradient* gradient );
+    void addStopsToGradient( QGradient* gradient, double alpha = 1 );
 
   protected:
     QColor mColor1, mColor2;

Original file line number	Diff line number	Diff line change
`@@ -678,7 +678,7 @@ void QgsGradientFillSymbolLayerV2::applyGradient( const QgsSymbolV2RenderContext`
`678`	`678`	`{`
`679`	`679`	`//color ramp gradient`
`680`	`680`	`QgsVectorGradientColorRampV2* gradRamp = static_cast<QgsVectorGradientColorRampV2*>( gradientRamp );`
`681`		`- gradRamp->addStopsToGradient( &gradient );`
	`681`	`+ gradRamp->addStopsToGradient( &gradient, context.alpha() );`
`682`	`682`	`}`
`683`	`683`	`else`
`684`	`684`	`{`