Revise advanced effects warning to account for GeoPDF capabilities

when exporting canvas to GeoPDF

python/core/auto_generated/qgsmapsettingsutils.sip.in

@@ -23,11 +23,18 @@ Utilities for map settings.
 %End
   public:
 
-    static const QStringList containsAdvancedEffects( const QgsMapSettings &mapSettings );
+    enum class EffectsCheckFlag
-%Docstring
+    {
-Checks whether any of the layers attached to a map settings object contain advanced effects
+      IgnoreGeoPdfSupportedEffects,
+    };
+    typedef QFlags<QgsMapSettingsUtils::EffectsCheckFlag> EffectsCheckFlags;
 
-:param mapSettings: map settings
+
+    static QStringList containsAdvancedEffects( const QgsMapSettings &mapSettings, EffectsCheckFlags flags = 0 );
+%Docstring
+Checks whether any of the layers attached to a map settings object contain advanced effects.
+
+The optional ``flags`` argument can be used to fine-tune the check behavior.
 %End
 
     static void worldFileParameters( const QgsMapSettings &mapSettings, double &a /Out/, double &b /Out/, double &c /Out/, double &d /Out/, double &e /Out/, double &f /Out/ );
@@ -57,6 +64,9 @@ Creates the content of a world file.
 
 };
 
+QFlags<QgsMapSettingsUtils::EffectsCheckFlag> operator|(QgsMapSettingsUtils::EffectsCheckFlag f1, QFlags<QgsMapSettingsUtils::EffectsCheckFlag> f2);
+
+
 /************************************************************************
  * This file has been generated automatically from                      *
  *                                                                      *

src/app/qgsmapsavedialog.cpp

@@ -99,11 +99,6 @@ QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, co
   {
     case Pdf:
     {
-      QStringList layers = QgsMapSettingsUtils::containsAdvancedEffects( mMapCanvas->mapSettings() );
-      if ( !layers.isEmpty() )
-      {
-        mInfoDetails = tr( "The following layer(s) use advanced effects:\n\n%1\n\nRasterizing map is recommended for proper rendering." ).arg(
-                         QChar( 0x2022 ) + QStringLiteral( " " ) + layers.join( QStringLiteral( "\n" ) + QChar( 0x2022 ) + QStringLiteral( " " ) ) );
       connect( mInfo, &QLabel::linkActivated, this, [this]( const QString & )
       {
         QgsMessageViewer *viewer = new QgsMessageViewer( this );
@@ -111,13 +106,6 @@ QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, co
         viewer->setMessageAsPlainText( mInfoDetails );
         viewer->exec();
       } );
-        mInfo->setText( tr( "%1A number of layers%2 use advanced effects, rasterizing map is recommended for proper rendering." ).arg( QStringLiteral( "<a href='#'>" ), QStringLiteral( "</a>" ) ) );
-        mSaveAsRaster->setChecked( true );
-      }
-      else
-      {
-        mSaveAsRaster->setChecked( false );
-      }
 
       this->setWindowTitle( tr( "Save Map as PDF" ) );
 
@@ -143,6 +131,9 @@ QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, co
         mGeoPdfFormatComboBox->addItem( tr( "ISO 32000 Extension (recommended)" ) );
         mGeoPdfFormatComboBox->addItem( tr( "OGC Best Practice" ) );
       }
+
+      connect( mGeoPDFGroupBox, &QGroupBox::toggled, this, &QgsMapSaveDialog::updatePdfExportWarning );
+      updatePdfExportWarning();
       break;
     }
 
@@ -574,6 +565,23 @@ void QgsMapSaveDialog::onAccepted()
   }
 }
 
+void QgsMapSaveDialog::updatePdfExportWarning()
+{
+  QStringList layers = QgsMapSettingsUtils::containsAdvancedEffects( mMapCanvas->mapSettings(), mGeoPDFGroupBox->isChecked() ? QgsMapSettingsUtils::EffectsCheckFlags( QgsMapSettingsUtils::EffectsCheckFlag::IgnoreGeoPdfSupportedEffects ) : nullptr );
+  if ( !layers.isEmpty() )
+  {
+    mInfoDetails = tr( "The following layer(s) use advanced effects:\n\n%1\n\nRasterizing map is recommended for proper rendering." ).arg(
+                     QChar( 0x2022 ) + QStringLiteral( " " ) + layers.join( QStringLiteral( "\n" ) + QChar( 0x2022 ) + QStringLiteral( " " ) ) );
+    mInfo->setText( tr( "%1A number of layers%2 use advanced effects, rasterizing map is recommended for proper rendering." ).arg( QStringLiteral( "<a href='#'>" ), QStringLiteral( "</a>" ) ) );
+    mSaveAsRaster->setChecked( true );
+  }
+  else
+  {
+    mSaveAsRaster->setChecked( false );
+    mInfo->clear();
+  }
+}
+
 void QgsMapSaveDialog::showHelp()
 {
   QgsHelp::openHelp( QStringLiteral( "introduction/qgis_gui.html#exporting-the-map-view" ) );

src/app/qgsmapsavedialog.h

@@ -86,6 +86,8 @@ class APP_EXPORT QgsMapSaveDialog: public QDialog, private Ui::QgsMapSaveDialog
   private slots:
     void onAccepted();
 
+    void updatePdfExportWarning();
+
   private:
 
     void lockChanged( bool locked );

src/core/qgsmapsettingsutils.cpp

@@ -20,10 +20,11 @@
 #include "qgspallabeling.h"
 #include "qgstextformat.h"
 #include "qgsvectorlayer.h"
+#include "qgsabstractgeopdfexporter.h"
 
 #include <QString>
 
-const QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSettings &mapSettings )
+QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSettings &mapSettings, EffectsCheckFlags flags )
 {
   QSet< QString > layers;
 
@@ -33,7 +34,20 @@ const QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSett
   {
     if ( layer && layer->isInScaleRange( mapSettings.scale() ) )
     {
+      bool layerHasAdvancedBlendMode = false;
       if ( layer->blendMode() != QPainter::CompositionMode_SourceOver )
+      {
+        if ( flags & EffectsCheckFlag::IgnoreGeoPdfSupportedEffects )
+        {
+          layerHasAdvancedBlendMode = !QgsAbstractGeoPdfExporter::compositionModeSupported( layer->blendMode() );
+        }
+        else
+        {
+          layerHasAdvancedBlendMode = true;
+        }
+      }
+
+      if ( layerHasAdvancedBlendMode )
       {
         layers << layer->name();
       }
@@ -41,7 +55,7 @@ const QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSett
       QgsVectorLayer *currentVectorLayer = qobject_cast<QgsVectorLayer *>( layer );
       if ( currentVectorLayer )
       {
-        if ( !qgsDoubleNear( currentVectorLayer->opacity(), 1.0 ) )
+        if ( !qgsDoubleNear( currentVectorLayer->opacity(), 1.0 ) && !( flags & EffectsCheckFlag::IgnoreGeoPdfSupportedEffects ) )
         {
           layers << layer->name();
         }

src/core/qgsmapsettingsutils.h

@@ -34,10 +34,21 @@ class CORE_EXPORT QgsMapSettingsUtils
   public:
 
     /**
-     * Checks whether any of the layers attached to a map settings object contain advanced effects
+     * Flags for controlling the behavior of containsAdvancedEffects()
-     * \param mapSettings map settings
+     * \since QGIS 3.14
      */
-    static const QStringList containsAdvancedEffects( const QgsMapSettings &mapSettings );
+    enum class EffectsCheckFlag
+    {
+      IgnoreGeoPdfSupportedEffects = 1 << 0, //!< Ignore advanced effects which are supported in GeoPDF exports
+    };
+    Q_DECLARE_FLAGS( EffectsCheckFlags, EffectsCheckFlag )
+
+    /**
+     * Checks whether any of the layers attached to a map settings object contain advanced effects.
+     *
+     * The optional \a flags argument can be used to fine-tune the check behavior.
+     */
+    static QStringList containsAdvancedEffects( const QgsMapSettings &mapSettings, EffectsCheckFlags flags = nullptr );
 
     /**
      * Computes the six parameters of a world file.
@@ -61,4 +72,6 @@ class CORE_EXPORT QgsMapSettingsUtils
 
 };
 
+Q_DECLARE_OPERATORS_FOR_FLAGS( QgsMapSettingsUtils::EffectsCheckFlags )
+
 #endif

tests/src/core/testqgsmapsettingsutils.cpp

@@ -80,12 +80,22 @@ void TestQgsMapSettingsUtils::containsAdvancedEffects()
   mapSettings.setLayers( layers );
 
   QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings ).size(), 1 );
+  QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings, QgsMapSettingsUtils::EffectsCheckFlag::IgnoreGeoPdfSupportedEffects ).size(), 0 );
 
   // set the layer scale-based visibility so it falls outside of the map settings scale
   layer->setScaleBasedVisibility( true );
   layer->setMaximumScale( 10 );
 
   QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings ).size(), 0 );
+
+  layer->setScaleBasedVisibility( false );
+  layer->setBlendMode( QPainter::CompositionMode_SourceOver );
+  QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings ).size(), 0 );
+  QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings, QgsMapSettingsUtils::EffectsCheckFlag::IgnoreGeoPdfSupportedEffects ).size(), 0 );
+
+  layer->setOpacity( 0.5 );
+  QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings ).size(), 1 );
+  QCOMPARE( QgsMapSettingsUtils::containsAdvancedEffects( mapSettings, QgsMapSettingsUtils::EffectsCheckFlag::IgnoreGeoPdfSupportedEffects ).size(), 0 );
 }
 
 QGSTEST_MAIN( TestQgsMapSettingsUtils )