[processing] Add spanner button next to Raster input combobox to open an advanced panel to specify raster source options (e.g., reference scale and DPI for WMS rasters). For now, the spanner button is only enabled for WMS layers.

src/gui/processing/qgsprocessingmaplayercombobox.cpp

@@ -25,6 +25,7 @@
 #include "qgsguiutils.h"
 #include "qgspanelwidget.h"
 #include "qgsprocessingfeaturesourceoptionswidget.h"
+#include "qgsprocessingrastersourceoptionswidget.h"
 #include "qgsdatasourceselectdialog.h"
 #include "qgsprocessingwidgetwrapper.h"
 #include "qgsprocessingprovider.h"
@@ -84,6 +85,22 @@ QgsProcessingMapLayerComboBox::QgsProcessingMapLayerComboBox( const QgsProcessin
     layout->addWidget( mSettingsButton );
     layout->setAlignment( mSettingsButton, Qt::AlignTop );
   }
+  else if ( mParameter->type() == QgsProcessingParameterRasterLayer::typeName() )
+  {
+    mSettingsButton = new QToolButton();
+    mSettingsButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "mActionOptions.svg" ) ) );
+    mSettingsButton->setToolTip( tr( "Advanced options" ) );
+    mSettingsButton->setEnabled( false ); // Only WMS layers will access raster advanced options for now
+
+    // button width is 1.25 * icon size, height 1.1 * icon size. But we round to ensure even pixel sizes for equal margins
+    mSettingsButton->setFixedSize( 2 * static_cast<int>( 1.25 * iconSize / 2.0 ), 2 * static_cast<int>( iconSize * 1.1 / 2.0 ) );
+    mSettingsButton->setIconSize( QSize( iconSize, iconSize ) );
+    mSettingsButton->setAutoRaise( true );
+
+    connect( mSettingsButton, &QToolButton::clicked, this, &QgsProcessingMapLayerComboBox::showRasterSourceOptions );
+    layout->addWidget( mSettingsButton );
+    layout->setAlignment( mSettingsButton, Qt::AlignTop );
+  }
 
   mSelectButton = new QToolButton();
   mSelectButton->setText( QString( QChar( 0x2026 ) ) );
@@ -269,6 +286,19 @@ void QgsProcessingMapLayerComboBox::setValue( const QVariant &value, QgsProcessi
     mGeometryCheck = Qgis::InvalidGeometryCheck::AbortOnInvalid;
   }
 
+  if ( val.userType() == qMetaTypeId<QgsProcessingRasterLayerDefinition>() )
+  {
+    QgsProcessingRasterLayerDefinition fromVar = qvariant_cast<QgsProcessingRasterLayerDefinition>( val );
+    val = fromVar.source;
+    mRasterReferenceScale = fromVar.referenceScale;
+    mRasterDpi = fromVar.dpi;
+  }
+  else
+  {
+    mRasterReferenceScale = 0;
+    mRasterDpi = 96;
+  }
+
   if ( val.userType() == qMetaTypeId<QgsProperty>() )
   {
     if ( val.value<QgsProperty>().propertyType() == Qgis::PropertyType::Static )
@@ -367,6 +397,8 @@ QVariant QgsProcessingMapLayerComboBox::value() const
   {
     if ( selectedOnly || iterate || mFeatureLimit != -1 || mIsOverridingDefaultGeometryCheck || !mFilterExpression.isEmpty() )
       return QgsProcessingFeatureSourceDefinition( layer->id(), selectedOnly, mFeatureLimit, ( iterate ? Qgis::ProcessingFeatureSourceDefinitionFlag::CreateIndividualOutputPerInputFeature : Qgis::ProcessingFeatureSourceDefinitionFlags() ) | ( mIsOverridingDefaultGeometryCheck ? Qgis::ProcessingFeatureSourceDefinitionFlag::OverrideDefaultGeometryCheck : Qgis::ProcessingFeatureSourceDefinitionFlags() ), mGeometryCheck, mFilterExpression );
+    else if ( mRasterReferenceScale != 0 )
+      return QgsProcessingRasterLayerDefinition( layer->id(), mRasterReferenceScale, mRasterDpi );
     else
       return layer->id();
   }
@@ -376,6 +408,8 @@ QVariant QgsProcessingMapLayerComboBox::value() const
     {
       if ( selectedOnly || iterate || mFeatureLimit != -1 || mIsOverridingDefaultGeometryCheck || !mFilterExpression.isEmpty() )
         return QgsProcessingFeatureSourceDefinition( mCombo->currentText(), selectedOnly, mFeatureLimit, ( iterate ? Qgis::ProcessingFeatureSourceDefinitionFlag::CreateIndividualOutputPerInputFeature : Qgis::ProcessingFeatureSourceDefinitionFlags() ) | ( mIsOverridingDefaultGeometryCheck ? Qgis::ProcessingFeatureSourceDefinitionFlag::OverrideDefaultGeometryCheck : Qgis::ProcessingFeatureSourceDefinitionFlags() ), mGeometryCheck, mFilterExpression );
+      else if ( mRasterReferenceScale != 0 )
+        return QgsProcessingRasterLayerDefinition( mCombo->currentText(), mRasterReferenceScale, mRasterDpi );
       else
         return mCombo->currentText();
     }
@@ -613,6 +647,12 @@ void QgsProcessingMapLayerComboBox::onLayerChanged( QgsMapLayer *layer )
     }
   }
 
+  if ( mParameter->type() == QgsProcessingParameterRasterLayer::typeName() )
+  {
+    // Only WMS layers will access raster advanced options for now
+    mSettingsButton->setEnabled( layer && layer->providerType() == QStringLiteral( "wms" ) );
+  }
+
   mPrevLayer = layer;
   if ( !mBlockChangedSignal )
     emit valueChanged();
@@ -657,6 +697,31 @@ void QgsProcessingMapLayerComboBox::showSourceOptions()
   }
 }
 
+void QgsProcessingMapLayerComboBox::showRasterSourceOptions()
+{
+  if ( QgsPanelWidget *panel = QgsPanelWidget::findParentPanel( this ) )
+  {
+    QgsProcessingRasterSourceOptionsWidget *widget = new QgsProcessingRasterSourceOptionsWidget();
+    widget->setPanelTitle( tr( "%1 Options" ).arg( mParameter->description() ) );
+    widget->setReferenceScale( mRasterReferenceScale );
+    widget->setDpi( mRasterDpi );
+
+    panel->openPanel( widget );
+
+    connect( widget, &QgsPanelWidget::widgetChanged, this, [this, widget] {
+      bool changed = false;
+      changed = changed | ( widget->referenceScale() != mRasterReferenceScale );
+      changed = changed | ( widget->dpi() != mRasterDpi );
+
+      mRasterReferenceScale = widget->referenceScale();
+      mRasterDpi = widget->dpi();
+
+      if ( changed )
+        emit valueChanged();
+    } );
+  }
+}
+
 void QgsProcessingMapLayerComboBox::selectFromFile()
 {
   QgsSettings settings;

src/gui/processing/qgsprocessingmaplayercombobox.h

@@ -131,6 +131,7 @@ class GUI_EXPORT QgsProcessingMapLayerComboBox : public QWidget
     void onLayerChanged( QgsMapLayer *layer );
     void selectionChanged( const QgsFeatureIds &selected, const QgsFeatureIds &deselected, bool clearAndSelect );
     void showSourceOptions();
+    void showRasterSourceOptions();
     void selectFromFile();
     void browseForLayer();
 
@@ -146,6 +147,8 @@ class GUI_EXPORT QgsProcessingMapLayerComboBox : public QWidget
     QString mFilterExpression;
     bool mIsOverridingDefaultGeometryCheck = false;
     Qgis::InvalidGeometryCheck mGeometryCheck = Qgis::InvalidGeometryCheck::AbortOnInvalid;
+    long mRasterReferenceScale = 0;
+    int mRasterDpi = 0;
     QPointer<QgsMapLayer> mPrevLayer;
     int mBlockChangedSignal = 0;