Simplify some painter related operations and make safer

qgis · Jul 4, 2020 · 61193fc · 61193fc
1 parent 8319fd7
commit 61193fc
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Showing 69 changed files with 183 additions and 298 deletions.
diff --git a/python/core/auto_generated/qgsrendercontext.sip.in b/python/core/auto_generated/qgsrendercontext.sip.in
@@ -111,6 +111,17 @@ Returns the destination QPainter for the render operation.
 %End
 
 
+    void setPainterFlagsUsingContext( QPainter *painter = 0 ) const;
+%Docstring
+Sets relevant flags on a destination ``painter``, using the flags and settings
+currently defined for the render context.
+
+If no ``painter`` is specified, then the flags will be applied to the render
+context's :py:func:`~QgsRenderContext.painter`.
+
+.. versionadded:: 3.16
+%End
+
     QPainter *maskPainter( int id = 0 );
 %Docstring
 Returns a mask QPainter for the render operation.

diff --git a/src/app/decorations/qgsdecorationcopyright.cpp b/src/app/decorations/qgsdecorationcopyright.cpp
@@ -116,9 +116,8 @@ void QgsDecorationCopyright::render( const QgsMapSettings &mapSettings, QgsRende
   if ( !enabled() )
     return;
 
-  context.painter()->save();
-  if ( context.flags() & QgsRenderContext::Antialiasing )
-    context.painter()->setRenderHint( QPainter::Antialiasing, true );
+  QgsScopedQPainterState painterState( context.painter() );
+  context.setPainterFlagsUsingContext();
 
   QString displayString = QgsExpression::replaceExpressionText( mLabelText, &context.expressionContext() );
   QStringList displayStringList = displayString.split( '\n' );
@@ -201,7 +200,5 @@ void QgsDecorationCopyright::render( const QgsMapSettings &mapSettings, QgsRende
 
   //Paint label to canvas
   QgsTextRenderer::drawText( QPointF( xOffset, yOffset ), 0.0, horizontalAlignment, displayStringList, context, mTextFormat );
-
-  context.painter()->restore();
 }
 
diff --git a/src/app/decorations/qgsdecorationimage.cpp b/src/app/decorations/qgsdecorationimage.cpp
@@ -199,7 +199,7 @@ void QgsDecorationImage::render( const QgsMapSettings &mapSettings, QgsRenderCon
       return;
   }
 
-  context.painter()->save();
+  QgsScopedQPainterState painterState( context.painter() );
 
   // need width/height of paint device
   QPaintDevice *device = context.painter()->device();
@@ -276,6 +276,4 @@ void QgsDecorationImage::render( const QgsMapSettings &mapSettings, QgsRenderCon
       // nothing happening here, function already returned in the first switch
       break;
   }
-
-  context.painter()->restore();
 }
diff --git a/src/app/decorations/qgsdecorationlayoutextent.cpp b/src/app/decorations/qgsdecorationlayoutextent.cpp
@@ -120,9 +120,9 @@ void QgsDecorationLayoutExtent::render( const QgsMapSettings &mapSettings, QgsRe
   if ( !mSymbol )
     return;
 
-  context.painter()->save();
-  if ( context.flags() & QgsRenderContext::Antialiasing )
-    context.painter()->setRenderHint( QPainter::Antialiasing, true );
+  QgsScopedQPainterState painterState( context.painter() );
+  context.setPainterFlagsUsingContext();
+
   mSymbol->startRender( context );
 
   const QgsMapToPixel &m2p = mapSettings.mapToPixel();
@@ -172,7 +172,6 @@ void QgsDecorationLayoutExtent::render( const QgsMapSettings &mapSettings, QgsRe
     }
   }
   mSymbol->stopRender( context );
-  context.painter()->restore();
 }
 
 bool QgsDecorationLayoutExtent::labelExtents() const

diff --git a/src/app/decorations/qgsdecorationnortharrow.cpp b/src/app/decorations/qgsdecorationnortharrow.cpp
@@ -140,7 +140,7 @@ void QgsDecorationNorthArrow::render( const QgsMapSettings &mapSettings, QgsRend
     double centerYDouble = size.height() / 2.0;
 
     //save the current canvas rotation
-    context.painter()->save();
+    QgsScopedQPainterState painterState( context.painter() );
     //
     //work out how to shift the image so that it rotates
     //           properly about its center
@@ -239,6 +239,5 @@ void QgsDecorationNorthArrow::render( const QgsMapSettings &mapSettings, QgsRend
     svg.render( context.painter(), QRectF( 0, 0, size.width(), size.height() ) );
 
     //unrotate the canvas again
-    context.painter()->restore();
   }
 }
diff --git a/src/app/decorations/qgsdecorationscalebar.cpp b/src/app/decorations/qgsdecorationscalebar.cpp
@@ -434,8 +434,7 @@ void QgsDecorationScaleBar::render( const QgsMapSettings &mapSettings, QgsRender
       QgsDebugMsg( QStringLiteral( "Unsupported placement index of %1" ).arg( static_cast<int>( mPlacement ) ) );
   }
 
-  context.painter()->save();
+  QgsScopedQPainterState painterState( context.painter() );
   context.painter()->translate( originX, originY );
   mStyle->draw( context, mSettings, scaleContext );
-  context.painter()->restore();
 }
diff --git a/src/app/decorations/qgsdecorationtitle.cpp b/src/app/decorations/qgsdecorationtitle.cpp
@@ -105,9 +105,8 @@ void QgsDecorationTitle::render( const QgsMapSettings &mapSettings, QgsRenderCon
   if ( !enabled() )
     return;
 
-  context.painter()->save();
-  if ( context.flags() & QgsRenderContext::Antialiasing )
-    context.painter()->setRenderHint( QPainter::Antialiasing, true );
+  QgsScopedQPainterState painterState( context.painter() );
+  context.setPainterFlagsUsingContext();
 
   QString displayString = QgsExpression::replaceExpressionText( mLabelText, &context.expressionContext() );
   QStringList displayStringList = displayString.split( '\n' );
@@ -221,7 +220,5 @@ void QgsDecorationTitle::render( const QgsMapSettings &mapSettings, QgsRenderCon
 
   // Paint label to canvas
   QgsTextRenderer::drawText( QPointF( xOffset, yOffset ), 0.0, horizontalAlignment, displayStringList, context, mTextFormat );
-
-  context.painter()->restore();
 }
 
diff --git a/src/app/georeferencer/qgsresidualplotitem.cpp b/src/app/georeferencer/qgsresidualplotitem.cpp
@@ -146,12 +146,11 @@ void QgsResidualPlotItem::paint( QPainter *painter, const QStyleOptionGraphicsIt
 
   if ( frameEnabled() )
   {
-    painter->save();
+    QgsScopedQPainterState painterState( painter );
     painter->setPen( pen() );
     painter->setBrush( Qt::NoBrush );
     painter->setRenderHint( QPainter::Antialiasing, true );
     painter->drawRect( QRectF( 0, 0, rect().width(), rect().height() ) );
-    painter->restore();
   }
 }
 
@@ -252,7 +251,7 @@ void QgsResidualPlotItem::drawArrowHead( QPainter *p, const double x, const doub
   arrowHeadPoly << QPointF( middlePoint.x() + p1Rotated.x(), middlePoint.y() + p1Rotated.y() );
   arrowHeadPoly << QPointF( middlePoint.x() + p2Rotated.x(), middlePoint.y() + p2Rotated.y() );
 
-  p->save();
+  QgsScopedQPainterState painterState( p );
 
   QPen arrowPen = p->pen();
   arrowPen.setJoinStyle( Qt::RoundJoin );
@@ -262,8 +261,6 @@ void QgsResidualPlotItem::drawArrowHead( QPainter *p, const double x, const doub
   p->setBrush( arrowBrush );
   arrowBrush.setStyle( Qt::SolidPattern );
   p->drawPolygon( arrowHeadPoly );
-
-  p->restore();
 }
 
 double QgsResidualPlotItem::angle( QPointF p1, QPointF p2 )

diff --git a/src/app/pluginmanager/qgspluginitemdelegate.cpp b/src/app/pluginmanager/qgspluginitemdelegate.cpp
@@ -16,6 +16,7 @@
  ***************************************************************************/
 
 #include "qgspluginitemdelegate.h"
+#include "qgsrendercontext.h"
 #include <QPainter>
 #include <QFont>
 #include <QStyleOptionViewItem>
@@ -39,7 +40,7 @@ QSize QgsPluginItemDelegate::sizeHint( const QStyleOptionViewItem &option, const
 
 void QgsPluginItemDelegate::paint( QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index ) const
 {
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
   painter->setRenderHint( QPainter::SmoothPixmapTransform );
   QStyle *style = QApplication::style();
   int pixelsHigh = QApplication::fontMetrics().height();
@@ -100,6 +101,4 @@ void QgsPluginItemDelegate::paint( QPainter *painter, const QStyleOptionViewItem
     painter->setFont( font );
   }
   painter->drawText( option.rect.left() + pixelsHigh * 2.4, option.rect.bottom() - pixelsHigh * 0.4, index.data( Qt::DisplayRole ).toString() );
-
-  painter->restore();
 }
diff --git a/src/app/qgsprojectlistitemdelegate.cpp b/src/app/qgsprojectlistitemdelegate.cpp
@@ -18,6 +18,7 @@
 #include "qgsnewsfeedmodel.h"
 #include "qgswebframe.h"
 #include "qgsapplication.h"
+#include "qgsrendercontext.h"
 
 #include <QApplication>
 #include <QPainter>
@@ -33,7 +34,7 @@ QgsProjectListItemDelegate::QgsProjectListItemDelegate( QObject *parent )
 
 void QgsProjectListItemDelegate::paint( QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index ) const
 {
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
 
   QTextDocument doc;
   QPixmap icon = qvariant_cast<QPixmap>( index.data( Qt::DecorationRole ) );
@@ -90,8 +91,6 @@ void QgsProjectListItemDelegate::paint( QPainter *painter, const QStyleOptionVie
   painter->translate( option.rect.left() + ( !icon.isNull() ? icon.width() + 3.125 * mRoundedRectSizePixels : 1.875 * mRoundedRectSizePixels ), option.rect.top() + 1.875 * mRoundedRectSizePixels );
   ctx.clip = QRect( 0, 0, option.rect.width() - ( !icon.isNull() ? icon.width() - 4.375 * mRoundedRectSizePixels : 3.125 *  mRoundedRectSizePixels ), option.rect.height() - 3.125 * mRoundedRectSizePixels );
   doc.documentLayout()->draw( painter, ctx );
-
-  painter->restore();
 }
 
 QSize QgsProjectListItemDelegate::sizeHint( const QStyleOptionViewItem &option, const QModelIndex &index ) const
@@ -189,7 +188,7 @@ QgsNewsItemListItemDelegate::QgsNewsItemListItemDelegate( QObject *parent )
 
 void QgsNewsItemListItemDelegate::paint( QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index ) const
 {
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
 
   QTextDocument doc;
   QPixmap icon = qvariant_cast<QPixmap>( index.data( Qt::DecorationRole ) );
@@ -253,8 +252,6 @@ void QgsNewsItemListItemDelegate::paint( QPainter *painter, const QStyleOptionVi
   painter->translate( option.rect.left() + ( !icon.isNull() ? icon.width() + 3.125 * mRoundedRectSizePixels : 1.875 * mRoundedRectSizePixels ), option.rect.top() + 1.875 * mRoundedRectSizePixels );
   ctx.clip = QRect( 0, 0, option.rect.width() - ( !icon.isNull() ? icon.width() - 4.375 * mRoundedRectSizePixels : 3.125 *  mRoundedRectSizePixels ), option.rect.height() - 3.125 * mRoundedRectSizePixels );
   doc.documentLayout()->draw( painter, ctx );
-
-  painter->restore();
 }
 
 QSize QgsNewsItemListItemDelegate::sizeHint( const QStyleOptionViewItem &option, const QModelIndex &index ) const

diff --git a/src/core/annotations/qgsannotation.cpp b/src/core/annotations/qgsannotation.cpp
@@ -138,7 +138,9 @@ void QgsAnnotation::render( QgsRenderContext &context ) const
     return;
   }
 
-  painter->save();
+  QgsScopedQPainterState painterState( context.painter() );
+  context.setPainterFlagsUsingContext();
+
   drawFrame( context );
   if ( mHasFixedMapPosition )
   {
@@ -162,7 +164,6 @@ void QgsAnnotation::render( QgsRenderContext &context ) const
 // context.painter()->scale( dotsPerMM, dotsPerMM );
 
   renderAnnotation( context, size );
-  painter->restore();
 }
 
 void QgsAnnotation::setMarkerSymbol( QgsMarkerSymbol *symbol )
@@ -354,8 +355,6 @@ void QgsAnnotation::drawFrame( QgsRenderContext &context ) const
   if ( !mFillSymbol )
     return;
 
-  context.painter()->setRenderHint( QPainter::Antialiasing, context.flags() & QgsRenderContext::Antialiasing );
-
   QPolygonF poly;
   poly.reserve( 9 + ( mHasFixedMapPosition ? 3 : 0 ) );
   QVector<QPolygonF> rings; //empty list

diff --git a/src/core/annotations/qgshtmlannotation.cpp b/src/core/annotations/qgshtmlannotation.cpp
@@ -84,15 +84,13 @@ void QgsHtmlAnnotation::renderAnnotation( QgsRenderContext &context, QSizeF size
   }
 
   // scale painter back to 96 dpi, so layout prints match screen rendering
-  context.painter()->save();
+  QgsScopedQPainterState painterState( context.painter() );
   const double scaleFactor = context.painter()->device()->logicalDpiX() / 96.0;
   context.painter()->scale( scaleFactor, scaleFactor );
   size /= scaleFactor;
 
   mWebPage->setViewportSize( size.toSize() );
   mWebPage->mainFrame()->render( context.painter() );
-
-  context.painter()->restore();
 }
 
 QSizeF QgsHtmlAnnotation::minimumFrameSize() const

diff --git a/src/core/annotations/qgstextannotation.cpp b/src/core/annotations/qgstextannotation.cpp
@@ -57,7 +57,7 @@ void QgsTextAnnotation::renderAnnotation( QgsRenderContext &context, QSizeF size
   }
 
   // scale painter back to 96 dpi, so layout prints match screen rendering
-  context.painter()->save();
+  QgsScopedQPainterState painterState( context.painter() );
   const double scaleFactor = context.painter()->device()->logicalDpiX() / 96.0;
   context.painter()->scale( scaleFactor, scaleFactor );
   size /= scaleFactor;
@@ -74,8 +74,6 @@ void QgsTextAnnotation::renderAnnotation( QgsRenderContext &context, QSizeF size
   }
   //draw text document
   mDocument->drawContents( painter, clipRect );
-
-  painter->restore();
 }
 
 void QgsTextAnnotation::writeXml( QDomElement &elem, QDomDocument &doc, const QgsReadWriteContext &context ) const

diff --git a/src/core/effects/qgsblureffect.cpp b/src/core/effects/qgsblureffect.cpp
@@ -65,10 +65,9 @@ void QgsBlurEffect::drawBlurredImage( QgsRenderContext &context, QImage &image )
   QgsImageOperation::multiplyOpacity( image, mOpacity );
 
   QPainter *painter = context.painter();
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
   painter->setCompositionMode( mBlendMode );
   painter->drawImage( imageOffset( context ), image );
-  painter->restore();
 }
 
 QgsStringMap QgsBlurEffect::properties() const

diff --git a/src/core/effects/qgscoloreffect.cpp b/src/core/effects/qgscoloreffect.cpp
@@ -50,10 +50,9 @@ void QgsColorEffect::draw( QgsRenderContext &context )
   QgsImageOperation::adjustHueSaturation( image, mSaturation, mColorizeOn ? mColorizeColor : QColor(), mColorizeStrength / 100.0 );
 
   QgsImageOperation::multiplyOpacity( image, mOpacity );
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
   painter->setCompositionMode( mBlendMode );
   painter->drawImage( imageOffset( context ), image );
-  painter->restore();
 }
 
 

diff --git a/src/core/effects/qgseffectstack.cpp b/src/core/effects/qgseffectstack.cpp
@@ -136,11 +136,9 @@ void QgsEffectStack::draw( QgsRenderContext &context )
     QPicture *pic = results.takeLast();
     if ( mEffectList.at( i )->drawMode() != QgsPaintEffect::Modifier )
     {
-      context.painter()->save();
+      QgsScopedQPainterState painterState( context.painter() );
       fixQPictureDpi( context.painter() );
       context.painter()->drawPicture( 0, 0, *pic );
-      context.painter()->restore();
-
     }
     delete pic;
   }

diff --git a/src/core/effects/qgsgloweffect.cpp b/src/core/effects/qgsgloweffect.cpp
@@ -92,10 +92,9 @@ void QgsGlowEffect::draw( QgsRenderContext &context )
   }
 
   QPainter *painter = context.painter();
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
   painter->setCompositionMode( mBlendMode );
   painter->drawImage( imageOffset( context ), im );
-  painter->restore();
 }
 
 QgsStringMap QgsGlowEffect::properties() const

diff --git a/src/core/effects/qgspainteffect.cpp b/src/core/effects/qgspainteffect.cpp
@@ -159,10 +159,9 @@ void QgsPaintEffect::drawSource( QPainter &painter )
 {
   if ( requiresQPainterDpiFix )
   {
-    painter.save();
+    QgsScopedQPainterState painterState( &painter );
     fixQPictureDpi( &painter );
     painter.drawPicture( 0, 0, *mPicture );
-    painter.restore();
   }
   else
   {
@@ -250,10 +249,9 @@ void QgsDrawSourceEffect::draw( QgsRenderContext &context )
     //rasterize source and apply modifications
     QImage image = sourceAsImage( context )->copy();
     QgsImageOperation::multiplyOpacity( image, mOpacity );
-    painter->save();
+    QgsScopedQPainterState painterState( painter );
     painter->setCompositionMode( mBlendMode );
     painter->drawImage( imageOffset( context ), image );
-    painter->restore();
   }
 }
 

diff --git a/src/core/effects/qgsshadoweffect.cpp b/src/core/effects/qgsshadoweffect.cpp
@@ -34,7 +34,7 @@ void QgsShadowEffect::draw( QgsRenderContext &context )
   QImage colorisedIm = sourceAsImage( context )->copy();
 
   QPainter *painter = context.painter();
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
   painter->setCompositionMode( mBlendMode );
 
   if ( !exteriorShadow() )
@@ -88,7 +88,6 @@ void QgsShadowEffect::draw( QgsRenderContext &context )
   {
     painter->drawImage( imageOffset( context ) + transPt, colorisedIm );
   }
-  painter->restore();
 }
 
 QgsStringMap QgsShadowEffect::properties() const

diff --git a/src/core/effects/qgstransformeffect.cpp b/src/core/effects/qgstransformeffect.cpp
@@ -36,13 +36,11 @@ void QgsTransformEffect::draw( QgsRenderContext &context )
   QPainter *painter = context.painter();
 
   //apply transformations
-  painter->save();
+  QgsScopedQPainterState painterState( painter );
 
   QTransform t = createTransform( context );
   painter->setTransform( t, true );
   drawSource( *painter );
-
-  painter->restore();
 }
 
 QgsStringMap QgsTransformEffect::properties() const