Flip symbology from alpha/transparency to opacity

Author: nyalldawson

doc/api_break.dox

@@ -1837,6 +1837,12 @@ QProgressDialog argument will need to be updated using manually created connecti
 signals and the updates to the progress dialog.
 
 
+QgsRasterFillSymbolLayer       {#qgis_api_break_3_0_QgsRasterFillSymbolLayer}
+-----------------
+
+- alpha() and setAlpha() were removed. Use opacity() and setOpacity() instead.
+
+
 QgsRasterInterface        {#qgis_api_break_3_0_QgsRasterInterface}
 ------------------
 
@@ -2108,6 +2114,7 @@ than an integer value
 - usedAttributes() now requires a QgsRenderContext argument.
 - setDataDefinedAngle(), dataDefinedAngle(), setDataDefinedSize(), dataDefinedSize(), setDataDefinedWidth() and dataDefinedWidth()
 now work with QgsProperty objects instead of QgsDataDefined.
+- alpha() and setAlpha() were removed. Use opacity() and setOpacity() instead.
 
 
 QgsSymbolLayer (renamed from QgsSymbolLayerV2)        {#qgis_api_break_3_0_QgsSymbolLayer}
@@ -2146,6 +2153,7 @@ QgsSymbolRenderContext (renamed from QgsSymbolV2RenderContext)        {#qgis_api
 - The constructor, setRenderHints() and renderHints() now accept and return a QgsSymbol::RenderHints flag rather
 than an integer value
 - fields() now returns a QgsFields value, not a pointer.
+- alpha() and setAlpha() were removed. Use opacity() and setOpacity() instead.
 
 
 QgsSymbolLayerUtils (renamed from QgsSymbolLayerUtilsV2)        {#qgis_api_break_3_0_QgsSymbolLayerUtils}

python/core/symbology-ng/qgsfillsymbollayer.sip

@@ -550,16 +550,8 @@ class QgsRasterFillSymbolLayer: QgsImageFillSymbolLayer
      */
     FillCoordinateMode coordinateMode() const;
 
-    /** Sets the opacity for the raster image used in the fill.
-     * @param alpha opacity value between 0 (fully transparent) and 1 (fully opaque)
-     * @see alpha
-     */
-    void setAlpha( const double alpha );
-    /** The opacity for the raster image used in the fill.
-     * @returns opacity value between 0 (fully transparent) and 1 (fully opaque)
-     * @see setAlpha
-     */
-    double alpha() const;
+    void setOpacity( const double opacity );
+    double opacity() const;
 
     /** Sets the offset for the fill.
      * @param offset offset for fill

python/core/symbology-ng/qgssymbol.sip

@@ -175,10 +175,8 @@ class QgsSymbol
     QgsMapUnitScale mapUnitScale() const;
     void setMapUnitScale( const QgsMapUnitScale &scale );
 
-    //! Get alpha transparency 1 for opaque, 0 for invisible
-    qreal alpha() const;
-    //! Set alpha transparency 1 for opaque, 0 for invisible
-    void setAlpha( qreal alpha );
+    qreal opacity() const;
+    void setOpacity( qreal opacity );
 
     /** Sets rendering hint flags for the symbol.
      * @see renderHints()
@@ -303,17 +301,7 @@ class QgsSymbolRenderContext
 
   public:
 
-    /** Constructor for QgsSymbolRenderContext
-     * @param c
-     * @param u
-     * @param alpha
-     * @param selected set to true if symbol should be drawn in a "selected" state
-     * @param renderHints flags controlling rendering behavior
-     * @param f
-     * @param fields
-     * @param mapUnitScale
-     */
-    QgsSymbolRenderContext( QgsRenderContext &c, QgsUnitTypes::RenderUnit u, qreal alpha = 1.0, bool selected = false, QgsSymbol::RenderHints renderHints = 0, const QgsFeature *f = 0, const QgsFields &fields = QgsFields(), const QgsMapUnitScale &mapUnitScale = QgsMapUnitScale() );
+    QgsSymbolRenderContext( QgsRenderContext &c, QgsUnitTypes::RenderUnit u, qreal opacity = 1.0, bool selected = false, QgsSymbol::RenderHints renderHints = 0, const QgsFeature *f = 0, const QgsFields &fields = QgsFields(), const QgsMapUnitScale &mapUnitScale = QgsMapUnitScale() );
     ~QgsSymbolRenderContext();
 
     QgsRenderContext &renderContext();
@@ -335,10 +323,8 @@ class QgsSymbolRenderContext
     QgsMapUnitScale mapUnitScale() const;
     void setMapUnitScale( const QgsMapUnitScale &scale );
 
-    //! Get alpha transparency 1 for opaque, 0 for invisible
-    qreal alpha() const;
-    //! Set alpha transparency 1 for opaque, 0 for invisible
-    void setAlpha( qreal alpha );
+    qreal opacity() const;
+    void setOpacity( qreal opacity );
 
     bool selected() const;
     void setSelected( bool selected );

python/gui/symbology-ng/qgssymbolslistwidget.sip

@@ -35,7 +35,6 @@ class QgsSymbolsListWidget : QWidget
     void saveSymbol();
     void symbolAddedToStyle( const QString &name, QgsSymbol *symbol );
     void on_mSymbolUnitWidget_changed();
-    void on_mTransparencySlider_valueChanged( int value );
 
     //! Pupulates the groups combo box with available tags and smartgroups
     void populateGroups();

src/app/qgsprojectproperties.cpp

@@ -1133,7 +1133,7 @@ void QgsProjectProperties::apply()
   QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/Line" ), cboStyleLine->currentText() );
   QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/Fill" ), cboStyleFill->currentText() );
   QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/ColorRamp" ), cboStyleColorRamp->currentText() );
-  QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/AlphaInt" ), ( int )( 255 - ( mTransparencySlider->value() * 2.55 ) ) );
+  QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/Opacity" ), 1.0 - mTransparencySlider->value() / 100.0 );
   QgsProject::instance()->writeEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/RandomColors" ), cbxStyleRandomColors->isChecked() );
   if ( mTreeProjectColors->isDirty() )
   {
@@ -1687,7 +1687,15 @@ void QgsProjectProperties::populateStyles()
   cbxStyleRandomColors->setChecked( QgsProject::instance()->readBoolEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/RandomColors" ), true ) );
 
   // alpha transparency
-  int transparencyInt = ( 255 - QgsProject::instance()->readNumEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/AlphaInt" ), 255 ) ) / 2.55;
+  int transparencyInt = 255;
+  bool ok = false;
+  double alpha = QgsProject::instance()->readDoubleEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/AlphaInt" ), 255, &ok );
+  if ( ok )
+    transparencyInt = alpha;
+  double newOpacity = QgsProject::instance()->readDoubleEntry( QStringLiteral( "DefaultStyles" ), QStringLiteral( "/Opacity" ), 1.0, &ok );
+  if ( ok )
+    transparencyInt = 255 - newOpacity * 255.0;
+
   mTransparencySlider->setValue( transparencyInt );
 }
 

src/core/composer/qgscomposermapoverview.cpp

@@ -58,7 +58,7 @@ void QgsComposerMapOverview::createDefaultFrameSymbol()
   properties.insert( QStringLiteral( "style" ), QStringLiteral( "solid" ) );
   properties.insert( QStringLiteral( "style_border" ), QStringLiteral( "no" ) );
   mFrameSymbol = QgsFillSymbol::createSimple( properties );
-  mFrameSymbol->setAlpha( 0.3 );
+  mFrameSymbol->setOpacity( 0.3 );
 }
 
 QgsComposerMapOverview::~QgsComposerMapOverview()

src/core/dxf/qgsdxfexport.cpp

@@ -897,7 +897,7 @@ void QgsDxfExport::writeBlocks()
       continue;
 
     // if point symbol layer and no data defined properties: write block
-    QgsSymbolRenderContext ctx( ct, QgsUnitTypes::RenderMapUnits, slIt->second->alpha(), false, slIt->second->renderHints(), nullptr );
+    QgsSymbolRenderContext ctx( ct, QgsUnitTypes::RenderMapUnits, slIt->second->opacity(), false, slIt->second->renderHints(), nullptr );
     ml->startRender( ctx );
 
     // markers with data defined properties are inserted inline

src/core/symbology-ng/qgsfillsymbollayer.cpp

@@ -232,20 +232,20 @@ QString QgsSimpleFillSymbolLayer::layerType() const
 void QgsSimpleFillSymbolLayer::startRender( QgsSymbolRenderContext &context )
 {
   QColor fillColor = mColor;
-  fillColor.setAlphaF( context.alpha() * mColor.alphaF() );
+  fillColor.setAlphaF( context.opacity() * mColor.alphaF() );
   mBrush = QBrush( fillColor, mBrushStyle );
 
   QColor selColor = context.renderContext().selectionColor();
   QColor selPenColor = selColor == mColor ? selColor : mStrokeColor;
-  if ( ! SELECTION_IS_OPAQUE ) selColor.setAlphaF( context.alpha() );
+  if ( ! SELECTION_IS_OPAQUE ) selColor.setAlphaF( context.opacity() );
   mSelBrush = QBrush( selColor );
   // N.B. unless a "selection line color" is implemented in addition to the "selection color" option
   // this would mean symbols with "no fill" look the same whether or not they are selected
   if ( SELECT_FILL_STYLE )
     mSelBrush.setStyle( mBrushStyle );
 
   QColor strokeColor = mStrokeColor;
-  strokeColor.setAlphaF( context.alpha() * mStrokeColor.alphaF() );
+  strokeColor.setAlphaF( context.opacity() * mStrokeColor.alphaF() );
   mPen = QPen( strokeColor );
   mSelPen = QPen( selPenColor );
   mPen.setStyle( mStrokeStyle );
@@ -767,9 +767,9 @@ void QgsGradientFillSymbolLayer::applyGradient( const QgsSymbolRenderContext &co
 {
   //update alpha of gradient colors
   QColor fillColor = color;
-  fillColor.setAlphaF( context.alpha() * fillColor.alphaF() );
+  fillColor.setAlphaF( context.opacity() * fillColor.alphaF() );
   QColor fillColor2 = color2;
-  fillColor2.setAlphaF( context.alpha() * fillColor2.alphaF() );
+  fillColor2.setAlphaF( context.opacity() * fillColor2.alphaF() );
 
   //rotate reference points
   QPointF rotatedReferencePoint1 = !qgsDoubleNear( angle, 0.0 ) ? rotateReferencePoint( referencePoint1, angle ) : referencePoint1;
@@ -817,7 +817,7 @@ void QgsGradientFillSymbolLayer::applyGradient( const QgsSymbolRenderContext &co
   {
     //color ramp gradient
     QgsGradientColorRamp *gradRamp = static_cast<QgsGradientColorRamp *>( gradientRamp );
-    gradRamp->addStopsToGradient( &gradient, context.alpha() );
+    gradRamp->addStopsToGradient( &gradient, context.opacity() );
   }
   else
   {
@@ -833,7 +833,8 @@ void QgsGradientFillSymbolLayer::applyGradient( const QgsSymbolRenderContext &co
 void QgsGradientFillSymbolLayer::startRender( QgsSymbolRenderContext &context )
 {
   QColor selColor = context.renderContext().selectionColor();
-  if ( ! SELECTION_IS_OPAQUE ) selColor.setAlphaF( context.alpha() );
+  if ( ! SELECTION_IS_OPAQUE )
+    selColor.setAlphaF( context.opacity() );
   mSelBrush = QBrush( selColor );
 }
 
@@ -1125,7 +1126,8 @@ void QgsShapeburstFillSymbolLayer::startRender( QgsSymbolRenderContext &context
 {
   //TODO - check this
   QColor selColor = context.renderContext().selectionColor();
-  if ( ! SELECTION_IS_OPAQUE ) selColor.setAlphaF( context.alpha() );
+  if ( ! SELECTION_IS_OPAQUE )
+    selColor.setAlphaF( context.opacity() );
   mSelBrush = QBrush( selColor );
 }
 
@@ -1237,7 +1239,7 @@ void QgsShapeburstFillSymbolLayer::renderPolygon( const QPolygonF &points, QList
 
   //copy distance transform values back to QImage, shading by appropriate color ramp
   dtArrayToQImage( dtArray, fillImage, mColorType == QgsShapeburstFillSymbolLayer::SimpleTwoColor ? mTwoColorGradientRamp : mGradientRamp,
-                   context.alpha(), useWholeShape, outputPixelMaxDist );
+                   context.opacity(), useWholeShape, outputPixelMaxDist );
 
   //clean up some variables
   delete [] dtArray;
@@ -1962,10 +1964,10 @@ void QgsSVGFillSymbolLayer::applyPattern( QBrush &brush, const QString &svgFileP
     }
 
     QTransform brushTransform;
-    if ( !qgsDoubleNear( context.alpha(), 1.0 ) )
+    if ( !qgsDoubleNear( context.opacity(), 1.0 ) )
     {
       QImage transparentImage = fitsInCache ? patternImage.copy() : mSvgPattern->copy();
-      QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.alpha() );
+      QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.opacity() );
       brush.setTextureImage( transparentImage );
     }
     else
@@ -2771,10 +2773,10 @@ void QgsLinePatternFillSymbolLayer::applyPattern( const QgsSymbolRenderContext &
   patternImage = patternImage.copy( xBuffer, yBuffer, patternImage.width() - 2 * xBuffer, patternImage.height() - 2 * yBuffer );
 
   //set image to mBrush
-  if ( !qgsDoubleNear( context.alpha(), 1.0 ) )
+  if ( !qgsDoubleNear( context.opacity(), 1.0 ) )
   {
     QImage transparentImage = patternImage.copy();
-    QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.alpha() );
+    QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.opacity() );
     brush.setTextureImage( transparentImage );
   }
   else
@@ -3185,10 +3187,10 @@ void QgsPointPatternFillSymbolLayer::applyPattern( const QgsSymbolRenderContext
     mMarkerSymbol->stopRender( pointRenderContext );
   }
 
-  if ( !qgsDoubleNear( context.alpha(), 1.0 ) )
+  if ( !qgsDoubleNear( context.opacity(), 1.0 ) )
   {
     QImage transparentImage = patternImage.copy();
-    QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.alpha() );
+    QgsSymbolLayerUtils::multiplyImageOpacity( &transparentImage, context.opacity() );
     brush.setTextureImage( transparentImage );
   }
   else
@@ -3418,7 +3420,7 @@ QColor QgsCentroidFillSymbolLayer::color() const
 
 void QgsCentroidFillSymbolLayer::startRender( QgsSymbolRenderContext &context )
 {
-  mMarker->setAlpha( context.alpha() );
+  mMarker->setOpacity( context.opacity() );
   mMarker->startRender( context.renderContext(), context.fields() );
 
   mCurrentFeatureId = -1;
@@ -3590,7 +3592,6 @@ QgsRasterFillSymbolLayer::QgsRasterFillSymbolLayer( const QString &imageFilePath
   : QgsImageFillSymbolLayer()
   , mImageFilePath( imageFilePath )
   , mCoordinateMode( QgsRasterFillSymbolLayer::Feature )
-  , mAlpha( 1.0 )
   , mOffsetUnit( QgsUnitTypes::RenderMillimeters )
   , mWidth( 0.0 )
   , mWidthUnit( QgsUnitTypes::RenderPixels )
@@ -3633,7 +3634,7 @@ QgsSymbolLayer *QgsRasterFillSymbolLayer::create( const QgsStringMap &properties
   }
   QgsRasterFillSymbolLayer *symbolLayer = new QgsRasterFillSymbolLayer( imagePath );
   symbolLayer->setCoordinateMode( mode );
-  symbolLayer->setAlpha( alpha );
+  symbolLayer->setOpacity( alpha );
   symbolLayer->setOffset( offset );
   symbolLayer->setAngle( angle );
   symbolLayer->setWidth( width );
@@ -3701,7 +3702,7 @@ void QgsRasterFillSymbolLayer::renderPolygon( const QPolygonF &points, QList<QPo
 
 void QgsRasterFillSymbolLayer::startRender( QgsSymbolRenderContext &context )
 {
-  applyPattern( mBrush, mImageFilePath, mWidth, mAlpha, context );
+  applyPattern( mBrush, mImageFilePath, mWidth, mOpacity, context );
 }
 
 void QgsRasterFillSymbolLayer::stopRender( QgsSymbolRenderContext &context )
@@ -3714,7 +3715,7 @@ QgsStringMap QgsRasterFillSymbolLayer::properties() const
   QgsStringMap map;
   map[QStringLiteral( "imageFile" )] = mImageFilePath;
   map[QStringLiteral( "coordinate_mode" )] = QString::number( mCoordinateMode );
-  map[QStringLiteral( "alpha" )] = QString::number( mAlpha );
+  map[QStringLiteral( "alpha" )] = QString::number( mOpacity );
   map[QStringLiteral( "offset" )] = QgsSymbolLayerUtils::encodePoint( mOffset );
   map[QStringLiteral( "offset_unit" )] = QgsUnitTypes::encodeUnit( mOffsetUnit );
   map[QStringLiteral( "offset_map_unit_scale" )] = QgsSymbolLayerUtils::encodeMapUnitScale( mOffsetMapUnitScale );
@@ -3729,7 +3730,7 @@ QgsRasterFillSymbolLayer *QgsRasterFillSymbolLayer::clone() const
 {
   QgsRasterFillSymbolLayer *sl = new QgsRasterFillSymbolLayer( mImageFilePath );
   sl->setCoordinateMode( mCoordinateMode );
-  sl->setAlpha( mAlpha );
+  sl->setOpacity( mOpacity );
   sl->setOffset( mOffset );
   sl->setOffsetUnit( mOffsetUnit );
   sl->setOffsetMapUnitScale( mOffsetMapUnitScale );
@@ -3757,9 +3758,9 @@ void QgsRasterFillSymbolLayer::setCoordinateMode( const QgsRasterFillSymbolLayer
   mCoordinateMode = mode;
 }
 
-void QgsRasterFillSymbolLayer::setAlpha( const double alpha )
+void QgsRasterFillSymbolLayer::setOpacity( const double opacity )
 {
-  mAlpha = alpha;
+  mOpacity = opacity;
 }
 
 void QgsRasterFillSymbolLayer::applyDataDefinedSettings( QgsSymbolRenderContext &context )
@@ -3769,10 +3770,10 @@ void QgsRasterFillSymbolLayer::applyDataDefinedSettings( QgsSymbolRenderContext
 
   bool hasWidthExpression = mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyWidth );
   bool hasFileExpression = mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyFile );
-  bool hasAlphaExpression = mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyAlpha );
+  bool hasOpacityExpression = mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyOpacity );
   bool hasAngleExpression = mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyAngle );
 
-  if ( !hasWidthExpression && !hasAngleExpression && !hasAlphaExpression && !hasFileExpression )
+  if ( !hasWidthExpression && !hasAngleExpression && !hasOpacityExpression && !hasFileExpression )
   {
     return; //no data defined settings
   }
@@ -3786,7 +3787,7 @@ void QgsRasterFillSymbolLayer::applyDataDefinedSettings( QgsSymbolRenderContext
       mNextAngle = nextAngle;
   }
 
-  if ( !hasWidthExpression && !hasAlphaExpression && !hasFileExpression )
+  if ( !hasWidthExpression && !hasOpacityExpression && !hasFileExpression )
   {
     return; //nothing further to do
   }
@@ -3797,19 +3798,19 @@ void QgsRasterFillSymbolLayer::applyDataDefinedSettings( QgsSymbolRenderContext
     context.setOriginalValueVariable( mWidth );
     width = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyWidth, context.renderContext().expressionContext(), width );
   }
-  double alpha = mAlpha;
-  if ( hasAlphaExpression )
+  double opacity = mOpacity;
+  if ( hasOpacityExpression )
   {
-    context.setOriginalValueVariable( mAlpha );
-    alpha = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyAlpha, context.renderContext().expressionContext(), alpha );
+    context.setOriginalValueVariable( mOpacity );
+    opacity = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyOpacity, context.renderContext().expressionContext(), opacity * 100 ) / 100.0;
   }
   QString file = mImageFilePath;
   if ( hasFileExpression )
   {
     context.setOriginalValueVariable( mImageFilePath );
     file = mDataDefinedProperties.valueAsString( QgsSymbolLayer::PropertyFile, context.renderContext().expressionContext(), file );
   }
-  applyPattern( mBrush, file, width, alpha, context );
+  applyPattern( mBrush, file, width, opacity, context );
 }
 
 void QgsRasterFillSymbolLayer::applyPattern( QBrush &brush, const QString &imageFilePath, const double width, const double alpha, const QgsSymbolRenderContext &context )