Map canvas uses renderer to QImage, fix for jumping image after pan

Author: wonder-sk

src/app/maprenderertest.cpp

@@ -57,7 +57,7 @@ int main(int argc, char* argv[])
   overview.show();
 
   QList<QgsMapCanvasLayer> layers;
-  layers.append(QgsMapCanvasLayer(layer2, false, true));
+  layers.append(QgsMapCanvasLayer(layer2, true, true));
   layers.append(QgsMapCanvasLayer(layer));
   canvas.setLayerSet(layers);
 

src/app/qgisapp.cpp

@@ -8120,13 +8120,6 @@ void QgisApp::projectProperties()
   long newCRSID = ms.destinationCrs().srsid();
   bool isProjected = ms.hasCrsTransformEnabled();
 
-  // projections have been turned on/off or dest CRS has changed while projections are on
-  if ( wasProjected != isProjected || ( isProjected && oldCRSID != newCRSID ) )
-  {
-    // TODO: would be better to try to reproject current extent to the new one
-    mMapCanvas->updateFullExtent();
-  }
-
   int  myRedInt = QgsProject::instance()->readNumEntry( "Gui", "/CanvasColorRedPart", 255 );
   int  myGreenInt = QgsProject::instance()->readNumEntry( "Gui", "/CanvasColorGreenPart", 255 );
   int  myBlueInt = QgsProject::instance()->readNumEntry( "Gui", "/CanvasColorBluePart", 255 );

src/gui/qgsmapcanvas.cpp

@@ -113,8 +113,6 @@ QgsMapCanvas::QgsMapCanvas( QWidget * parent, const char *name )
   mScene->addItem( mMap );
   mScene->update(); // porting??
 
-  moveCanvasContents( true );
-
   connect( mMapRenderer, SIGNAL( drawError( QgsMapLayer* ) ), this, SLOT( showError( QgsMapLayer* ) ) );
 
   // TODO: propagate signals to map renderer?
@@ -126,9 +124,12 @@ QgsMapCanvas::QgsMapCanvas( QWidget * parent, const char *name )
   connect( QgsProject::instance(), SIGNAL( writeProject( QDomDocument & ) ),
            this, SLOT( writeProject( QDomDocument & ) ) );
 
-  mSettings.setOutputDpi(120);  // TODO: what to set ???
   mSettings.setOutputSize( size() );
   mMap->resize( size() );
+  setSceneRect( 0, 0, size().width(), size().height() );
+  mScene->setSceneRect( QRectF( 0, 0, size().width(), size().height() ) );
+
+  moveCanvasContents( true );
 
 #ifdef Q_OS_WIN
   // Enable touch event on Windows.
@@ -287,7 +288,6 @@ void QgsMapCanvas::setLayerSet( QList<QgsMapCanvasLayer> &layers )
     }
 
     mSettings.setLayers( layerSet );
-    //mMapRenderer->setLayerSet( layerSet );
 
     for ( i = 0; i < layerCount(); i++ )
     {
@@ -540,19 +540,9 @@ QgsRectangle QgsMapCanvas::extent() const
 
 QgsRectangle QgsMapCanvas::fullExtent() const
 {
-  return mapSettings().fullExtent(); //mMapRenderer->fullExtent();
+  return mapSettings().fullExtent();
 } // extent
 
-void QgsMapCanvas::updateFullExtent()
-{
-  // projection settings have changed
-/*
-  QgsDebugMsg( "updating full extent" );
-
-  mMapRenderer->updateFullExtent();
-  refresh();
-*/
-}
 
 void QgsMapCanvas::setExtent( QgsRectangle const & r )
 {
@@ -564,12 +554,10 @@ void QgsMapCanvas::setExtent( QgsRectangle const & r )
     QgsRectangle e( QgsPoint( r.center().x() - current.width() / 2.0, r.center().y() - current.height() / 2.0 ),
                     QgsPoint( r.center().x() + current.width() / 2.0, r.center().y() + current.height() / 2.0 ) );
     mSettings.setExtent( e );
-    //mMapRenderer->setExtent( e );
   }
   else
   {
     mSettings.setExtent( r );
-    //mMapRenderer->setExtent( r );
   }
   emit extentsChanged();
   updateScale();
@@ -641,7 +629,6 @@ void QgsMapCanvas::zoomToPreviousExtent()
   {
     mLastExtentIndex--;
     mSettings.setExtent( mLastExtent[mLastExtentIndex] );
-    //mMapRenderer->setExtent( mLastExtent[mLastExtentIndex] );
     emit extentsChanged();
     updateScale();
     if ( mMapOverview )
@@ -662,7 +649,6 @@ void QgsMapCanvas::zoomToNextExtent()
   {
     mLastExtentIndex++;
     mSettings.setExtent( mLastExtent[mLastExtentIndex] );
-    //mMapRenderer->setExtent( mLastExtent[mLastExtentIndex] );
     emit extentsChanged();
     updateScale();
     if ( mMapOverview )
@@ -993,6 +979,8 @@ void QgsMapCanvas::resizeEvent( QResizeEvent * e )
   mMap->resize( lastSize );
   mScene->setSceneRect( QRectF( 0, 0, lastSize.width(), lastSize.height() ) );
 
+  moveCanvasContents( true );
+
   // notify canvas items of change
   updateCanvasItemPositions();
 
@@ -1005,22 +993,6 @@ void QgsMapCanvas::resizeEvent( QResizeEvent * e )
 
 void QgsMapCanvas::paintEvent( QPaintEvent *e )
 {
-  /*
-    if ( mPainting || mDrawing )
-    {
-      //cancel current render progress
-      if ( mMapRenderer )
-      {
-        QgsRenderContext* theRenderContext = mMapRenderer->rendererContext();
-        if ( theRenderContext )
-        {
-          theRenderContext->setRenderingStopped( true );
-        }
-      }
-      return;
-    }
-  */
-
   QGraphicsView::paintEvent( e );
 } // paintEvent
 
@@ -1284,7 +1256,6 @@ double QgsMapCanvas::mapUnitsPerPixel() const
 void QgsMapCanvas::setMapUnits( QGis::UnitType u )
 {
   QgsDebugMsg( "Setting map units to " + QString::number( static_cast<int>( u ) ) );
-  //mMapRenderer->setMapUnits( u );
   mSettings.setMapUnits( u );
 }
 
@@ -1331,6 +1302,8 @@ void QgsMapCanvas::panActionEnd( QPoint releasePoint )
   // move map image and other items to standard position
   moveCanvasContents( true ); // true means reset
 
+  mMap->mapDragged( releasePoint - mCanvasProperties->rubberStartPoint );
+
   // use start and end box points to calculate the extent
   QgsPoint start = getCoordinateTransform()->toMapCoordinates( mCanvasProperties->rubberStartPoint );
   QgsPoint end = getCoordinateTransform()->toMapCoordinates( releasePoint );
@@ -1341,7 +1314,6 @@ void QgsMapCanvas::panActionEnd( QPoint releasePoint )
   double dx = qAbs( end.x() - start.x() );
   double dy = qAbs( end.y() - start.y() );
 
-
   // modify the extent
   QgsRectangle r = mapSettings().visibleExtent();
 
@@ -1386,9 +1358,6 @@ void QgsMapCanvas::panAction( QMouseEvent * e )
 
   // move all map canvas items
   moveCanvasContents();
-
-  // update canvas
-  //updateContents(); // TODO: need to update?
 }
 
 void QgsMapCanvas::moveCanvasContents( bool reset )
@@ -1397,28 +1366,7 @@ void QgsMapCanvas::moveCanvasContents( bool reset )
   if ( !reset )
     pnt += mCanvasProperties->mouseLastXY - mCanvasProperties->rubberStartPoint;
 
-  mMap->setPanningOffset( pnt );
-
-  QList<QGraphicsItem*> list = mScene->items();
-  QList<QGraphicsItem*>::iterator it = list.begin();
-  while ( it != list.end() )
-  {
-    QGraphicsItem* item = *it;
-
-    if ( item != mMap )
-    {
-      // this tells map canvas item to draw with offset
-      QgsMapCanvasItem* canvasItem = dynamic_cast<QgsMapCanvasItem *>( item );
-      if ( canvasItem )
-        canvasItem->setPanningOffset( pnt );
-    }
-
-    it++;
-  }
-
-  // show items
-  updateCanvasItemPositions();
-
+  setSceneRect( -pnt.x(), -pnt.y(), size().width(), size().height() );
 }
 
 void QgsMapCanvas::showError( QgsMapLayer * mapLayer )

src/gui/qgsmapcanvas.h

@@ -201,6 +201,7 @@ class GUI_EXPORT QgsMapCanvas : public QGraphicsView
     void updateScale();
 
     /** Updates the full extent */
+    //! @deprecated since v2.1 - does nothing
     void updateFullExtent();
 
     //! return the map layer at position index in the layer stack

src/gui/qgsmapcanvasitem.h

@@ -63,7 +63,8 @@ class GUI_EXPORT QgsMapCanvasItem : public QGraphicsItem
     virtual QRectF boundingRect() const;
 
     //! sets current offset, to be called from QgsMapCanvas
-    void setPanningOffset( const QPoint& point );
+    //! @deprecated since v2.1 - not called by QgsMapCanvas anymore
+    Q_DECL_DEPRECATED void setPanningOffset( const QPoint& point );
 
     //! returns canvas item rectangle
     QgsRectangle rect() const;

src/gui/qgsmapcanvasmap.cpp

@@ -26,6 +26,7 @@ QgsMapCanvasMap::QgsMapCanvasMap( QgsMapCanvas* canvas )
     : mCanvas( canvas )
     , mDirty(true)
     , mJob(0)
+    , mOffset()
 {
   setZValue( -10 );
   setPos( 0, 0 );
@@ -59,8 +60,6 @@ void QgsMapCanvasMap::paint( QPainter* p, const QStyleOptionGraphicsItem*, QWidg
 {
   qDebug("paint()");
 
-  bool paintedAlready = false;
-
   if (mDirty)
   {
     if (mJob)
@@ -72,31 +71,24 @@ void QgsMapCanvasMap::paint( QPainter* p, const QStyleOptionGraphicsItem*, QWidg
       qDebug("need to render");
 
       // draw the image before it will be wiped out
-      // TODO: does not work correctly with panning by dragging
-      p->drawImage( 0, 0, mImage );
-      paintedAlready = true;
-
-      const QgsMapSettings& s = mCanvas->mapSettings();
-
-      qDebug("----------> EXTENT %f,%f", s.extent().xMinimum(), s.extent().yMinimum());
-
-      mPainter = new QPainter(&mImage);
+      p->drawImage( mOffset, mImage );
 
       // TODO[MD]: need to setup clipping?
       //paint.setClipRect( mImage.rect() );
 
       // create the renderer job
       Q_ASSERT(mJob == 0);
-      mJob = new QgsMapRendererCustomPainterJob(s, mPainter);
+      mJob = new QgsMapRendererSequentialJob( mCanvas->mapSettings() );
       connect(mJob, SIGNAL(finished()), SLOT(finish()));
       mJob->start();
 
       mTimer.start();
+
+      mOffset = QPoint();
+      return;
     }
   }
 
-  if (!paintedAlready)
-  {
 #ifdef EGA_MODE
   QImage i2( mImage.size()/3, mImage.format() );
   QPainter p2(&i2);
@@ -106,12 +98,12 @@ void QgsMapCanvasMap::paint( QPainter* p, const QStyleOptionGraphicsItem*, QWidg
 #else
   p->drawImage( 0, 0, mImage );
 #endif
-  }
 }
 
 QRectF QgsMapCanvasMap::boundingRect() const
 {
-  return QRectF( 0, 0, mImage.width(), mImage.height() );
+  QSize s = mCanvas->mapSettings().outputSize();
+  return QRectF( 0, 0, s.width(), s.height() ); // mImage.width(), mImage.height() );
 }
 
 
@@ -127,15 +119,6 @@ void QgsMapCanvasMap::resize( QSize size )
 
   QgsDebugMsg( QString( "resizing to %1x%2" ).arg( size.width() ).arg( size.height() ) );
   prepareGeometryChange(); // to keep QGraphicsScene indexes up to date on size change
-
-  mImage = QImage( size, QImage::Format_ARGB32_Premultiplied );
-  //mCanvas->mapRenderer()->setOutputSize( size, mImage.logicalDpiX() );
-}
-
-void QgsMapCanvasMap::setPanningOffset( const QPoint& point )
-{
-  mOffset = point;
-  setPos( mOffset );
 }
 
 QPaintDevice& QgsMapCanvasMap::paintDevice()
@@ -152,10 +135,7 @@ void QgsMapCanvasMap::finish()
 
   mDirty = false;
 
-  delete mPainter;
-  mPainter = 0;
-
-  //mLastImage = mImage;
+  mImage = mJob->renderedImage();
 
   update();
 }
@@ -165,5 +145,14 @@ void QgsMapCanvasMap::onMapUpdateTimeout()
 {
   qDebug("update timer!");
 
+  mImage = mJob->renderedImage();
+
+  update();
+}
+
+
+void QgsMapCanvasMap::mapDragged(const QPoint &diff)
+{
+  mOffset = diff;
   update();
 }

src/gui/qgsmapcanvasmap.h

@@ -56,7 +56,8 @@ class GUI_EXPORT QgsMapCanvasMap : public QObject, public QGraphicsRectItem
     //! @deprecated in 2.1 - does nothing. Kept for API compatibility
     void setBackgroundColor( const QColor& color ) {}
 
-    void setPanningOffset( const QPoint& point );
+    //! @deprecated in 2.1 - not called by QgsMapCanvas anymore
+    Q_DECL_DEPRECATED void setPanningOffset( const QPoint& point ) {}
 
     //! @deprecated in 2.1
     QPaintDevice& paintDevice();
@@ -70,25 +71,25 @@ class GUI_EXPORT QgsMapCanvasMap : public QObject, public QGraphicsRectItem
 
     const QgsMapSettings& settings() const;
 
+    //! called by map canvas to handle panning with mouse (kind of)
+    //! @note added in 2.1
+    void mapDragged( const QPoint& diff);
+
 public slots:
     void finish();
     void onMapUpdateTimeout();
 
   private:
 
     QImage mImage;
-    QImage mLastImage;
 
-    //QgsMapRenderer* mRender;
     QgsMapCanvas* mCanvas;
 
     QPoint mOffset;
 
     bool mDirty; //!< whether a new rendering job should be started upon next paint() call
 
-    QgsMapRendererCustomPainterJob* mJob;
-
-    QPainter* mPainter;
+    QgsMapRendererSequentialJob* mJob;
 
     QTimer mTimer;
 };

src/gui/qgsmapoverviewcanvas.cpp

@@ -112,7 +112,7 @@ void QgsMapOverviewCanvas::drawExtentRect()
   const QgsRectangle& extent = mMapCanvas->extent();
 
   // show only when valid extent is set
-  if ( extent.isEmpty() || mSettings.extent().isEmpty() )
+  if ( extent.isEmpty() || mSettings.visibleExtent().isEmpty() )
   {
     mPanningWidget->hide();
     return;