Add ability to define QImage format for render jobs via map settings

- Defaults to QImage::Format_ARGB32_Premultiplied, as before
- Update labeling unit tests to use defined format

python/core/qgsmapsettings.sip

@@ -72,6 +72,11 @@ class QgsMapSettings
     Flags flags() const;
     bool testFlag( Flag flag ) const;
 
+    //! sets format of internal QImage
+    void setOutputImageFormat( QImage::Format format );
+    //! format of internal QImage, default QImage::Format_ARGB32_Premultiplied
+    QImage::Format outputImageFormat() const;
+
     bool hasValidSettings() const;
     QgsRectangle visibleExtent() const;
     double mapUnitsPerPixel() const;

src/core/composer/qgscomposermap.cpp

@@ -186,6 +186,7 @@ void QgsComposerMap::draw( QPainter *painter, const QgsRectangle& extent, const
   jobMapSettings.setMapUnits( ms.mapUnits() );
   jobMapSettings.setBackgroundColor( Qt::transparent );
   jobMapSettings.setShowSelection( false );
+  jobMapSettings.setOutputImageFormat( ms.outputImageFormat() );
 
   //set layers to render
   QStringList theLayerSet = layersToRender();

src/core/qgsmaprendererjob.cpp

@@ -50,7 +50,7 @@ QgsMapRendererSequentialJob::QgsMapRendererSequentialJob( const QgsMapSettings&
 {
   QgsDebugMsg( "SEQUENTIAL construct" );
 
-  mImage = QImage( mSettings.outputSize(), QImage::Format_ARGB32_Premultiplied );
+  mImage = QImage( mSettings.outputSize(), mSettings.outputImageFormat() );
 }
 
 QgsMapRendererSequentialJob::~QgsMapRendererSequentialJob()
@@ -639,7 +639,8 @@ LayerRenderJobs QgsMapRendererJob::prepareJobs( QPainter* painter, QgsPalLabelin
       // Flattened image for drawing when a blending mode is set
       QImage * mypFlattenedImage = 0;
       mypFlattenedImage = new QImage( mSettings.outputSize().width(),
-                                      mSettings.outputSize().height(), QImage::Format_ARGB32_Premultiplied );
+                                      mSettings.outputSize().height(),
+                                      mSettings.outputImageFormat() );
       if ( mypFlattenedImage->isNull() )
       {
         mErrors.append( Error( layerId, "Insufficient memory for image " + QString::number( mSettings.outputSize().width() ) + "x" + QString::number( mSettings.outputSize().height() ) ) );
@@ -915,7 +916,7 @@ void QgsMapRendererParallelJob::renderLabelsStatic( QgsMapRendererParallelJob* s
 
 QImage QgsMapRendererJob::composeImage( const QgsMapSettings& settings, const LayerRenderJobs& jobs )
 {
-  QImage image( settings.outputSize(), QImage::Format_ARGB32_Premultiplied );
+  QImage image( settings.outputSize(), settings.outputImageFormat() );
   image.fill( settings.backgroundColor().rgb() );
 
   QPainter painter( &image );

src/core/qgsmapsettings.cpp

@@ -27,6 +27,7 @@ QgsMapSettings::QgsMapSettings()
     , mSelectionColor( Qt::yellow )
     , mShowSelection( true )
     , mFlags( Antialiasing | UseAdvancedEffects | DrawLabeling )
+    , mImageFormat( QImage::Format_ARGB32_Premultiplied )
 {
   updateDerived();
 

src/core/qgsmapsettings.h

@@ -2,6 +2,7 @@
 #define QGSMAPSETTINGS_H
 
 #include <QColor>
+#include <QImage>
 #include <QSize>
 #include <QStringList>
 
@@ -88,6 +89,11 @@ class CORE_EXPORT QgsMapSettings
     Flags flags() const;
     bool testFlag( Flag flag ) const;
 
+    //! sets format of internal QImage
+    void setOutputImageFormat( QImage::Format format ) { mImageFormat = format; }
+    //! format of internal QImage, default QImage::Format_ARGB32_Premultiplied
+    QImage::Format outputImageFormat() const { return mImageFormat; }
+
     bool hasValidSettings() const;
     QgsRectangle visibleExtent() const;
     double mapUnitsPerPixel() const;
@@ -178,6 +184,8 @@ class CORE_EXPORT QgsMapSettings
 
     Flags mFlags;
 
+    QImage::Format mImageFormat;
+
     // derived properties
     bool mValid; //!< whether the actual settings are valid (set in updateDerived())
     QgsRectangle mVisibleExtent; //!< extent with some additional white space that matches the output aspect ratio

tests/src/python/test_qgspallabeling_base.py

@@ -233,6 +233,7 @@ class TestQgsPalLabeling(TestCase):
         ms.setCrsTransformEnabled(oms.hasCrsTransformEnabled())
         ms.setMapUnits(oms.mapUnits())
         ms.setExtent(oms.extent())
+        ms.setOutputImageFormat(oms.outputImageFormat())
 
         ms.setLayers(oms.layers())
         return ms

tests/src/python/test_qgspallabeling_composer.py

@@ -123,19 +123,22 @@ class TestComposerBase(TestQgsPalLabeling):
 
     # noinspection PyUnusedLocal
     def _get_composer_image(self, width, height, dpi):
-        # image = QImage(QSize(width, height), QImage.Format_ARGB32)
+        image = QImage(QSize(width, height),
-        # image.fill(QColor(152, 219, 249).rgb())
+                       self._TestMapSettings.outputImageFormat())
-        # image.setDotsPerMeterX(dpi / 25.4 * 1000)
+        image.fill(QColor(152, 219, 249).rgb())
-        # image.setDotsPerMeterY(dpi / 25.4 * 1000)
+        image.setDotsPerMeterX(dpi / 25.4 * 1000)
-        #
+        image.setDotsPerMeterY(dpi / 25.4 * 1000)
-        # p = QPainter(image)
-        # p.setRenderHint(QPainter.Antialiasing, False)
-        # p.setRenderHint(QPainter.HighQualityAntialiasing, False)
-        # self._c.renderPage(p, 0)
-        # p.end()
 
-        image = self._c.printPageAsRaster(0)
+        p = QPainter(image)
-        """:type: QImage"""
+        p.setRenderHint(
+            QPainter.Antialiasing,
+            self._TestMapSettings.testFlag(QgsMapSettings.Antialiasing)
+        )
+        self._c.renderPage(p, 0)
+        p.end()
+
+        # image = self._c.printPageAsRaster(0)
+        # """:type: QImage"""
 
         if image.isNull():
             return False, ''
@@ -169,13 +172,18 @@ class TestComposerBase(TestQgsPalLabeling):
         if temp_size == os.path.getsize(svgpath):
             return False, ''
 
-        image = QImage(width, height, QImage.Format_ARGB32)
+        image = QImage(width, height, self._TestMapSettings.outputImageFormat())
         image.fill(QColor(152, 219, 249).rgb())
         image.setDotsPerMeterX(dpi / 25.4 * 1000)
         image.setDotsPerMeterY(dpi / 25.4 * 1000)
 
         svgr = QSvgRenderer(svgpath)
         p = QPainter(image)
+        p.setRenderHint(
+            QPainter.Antialiasing,
+            self._TestMapSettings.testFlag(QgsMapSettings.Antialiasing)
+        )
+        p.setRenderHint(QPainter.TextAntialiasing)
         svgr.render(p)
         p.end()
 

tests/src/python/utilities.py

@@ -302,6 +302,7 @@ def mapSettingsString(ms):
         ms.testFlag(QgsMapSettings.DrawLabeling))
     s += '  flag.DrawEditingInfo: {0}\n'.format(
         ms.testFlag(QgsMapSettings.DrawEditingInfo))
+    s += '  outputImageFormat(): {0}\n'.format(ms.outputImageFormat())
     return s