Feature #8725: Fast rendering of geometries

i18n/qgis_es.ts

@@ -49496,6 +49496,10 @@ Should the existing classes be deleted before classification?</source>
         <source>General</source>
         <translation>General</translation>
     </message>
+    <message>
+        <source>Rendering</source>
+        <translation>Representación</translation>
+    </message>
     <message>
         <source>Display name</source>
         <translation type="obsolete">Mostrar el nombre</translation>
@@ -49944,6 +49948,22 @@ Should the existing classes be deleted before classification?</source>
         <source>Type</source>
         <translation>Tipo</translation>
     </message>
+    <message>
+        <source>Fast drawing</source>
+        <translation>Pintado rápido</translation>
+    </message>
+    <message>
+        <source>&lt;b&gt;Note:&lt;/b&gt; This option enables geometry simplification drawing for fast rendering of the layer.</source>
+        <translation>&lt;b&gt;Nota:&lt;/b&gt; Esta opción activa el pintado simplificado de las geometrías para acelerar la representación de la capa.</translation>
+    </message>
+    <message>
+        <source>Simplification factor (Higher value draws more simplified geometries):  </source>
+        <translation>Factor de simplificación (Cuanto mayor es el valor más se simplifica la geometría):  </translation>
+    </message>
+    <message>
+        <source>Higher value draws more simplified geometries</source>
+        <translation>Cuanto mayor es el valor más se simplifica la geometría</translation>
+    </message>
 </context>
 <context>
     <name>QgsVectorLayerSaveAsDialog</name>

python/core/symbology-ng/qgssymbollayerv2.sip

@@ -202,5 +202,5 @@ class QgsFillSymbolLayerV2 : QgsSymbolLayerV2
   protected:
     QgsFillSymbolLayerV2( bool locked = false );
     /**Default method to render polygon*/
-    void _renderPolygon( QPainter* p, const QPolygonF& points, const QList<QPolygonF>* rings );
+    void _renderPolygon( QPainter* p, const QPolygonF& points, const QList<QPolygonF>* rings, QgsSymbolV2RenderContext& context );
 };

src/app/qgsoptions.cpp

@@ -560,6 +560,11 @@ QgsOptions::QgsOptions( QWidget *parent, Qt::WFlags fl ) :
   chkAntiAliasing->setChecked( settings.value( "/qgis/enable_anti_aliasing", true ).toBool() );
   chkUseRenderCaching->setChecked( settings.value( "/qgis/enable_render_caching", false ).toBool() );
 
+  // Default simplify drawing configuration
+  mSimplifyDrawingGroupBox->setChecked( settings.value( "/qgis/simplifyDrawingHints", (int)QgsVectorLayer::DefaultSimplification ).toInt() != QgsVectorLayer::NoSimplification );
+  mSimplifyDrawingSlider->setValue( (int)(5.0f * (settings.value( "/qgis/simplifyDrawingTol", QGis::DEFAULT_MAPTOPIXEL_THRESHOLD ).toFloat()-1)) );
+  mSimplifyDrawingPanel->setVisible( mSimplifyDrawingSlider->value()>0 );
+
   // Slightly awkard here at the settings value is true to use QImage,
   // but the checkbox is true to use QPixmap
   chkUseQPixmap->setChecked( !( settings.value( "/qgis/use_qimage_to_render", true ).toBool() ) );
@@ -1091,6 +1096,16 @@ void QgsOptions::saveOptions()
   bool legendLayersCapitalise = settings.value( "/qgis/capitaliseLayerName", false ).toBool();
   settings.setValue( "/qgis/capitaliseLayerName", capitaliseCheckBox->isChecked() );
 
+  // Default simplify drawing configuration
+  int simplifyDrawingHints = QgsVectorLayer::NoSimplification;
+  if ( mSimplifyDrawingGroupBox->isChecked() )
+  {
+    simplifyDrawingHints |= QgsVectorLayer::DefaultSimplification;
+    if ( mSimplifyDrawingSlider->value() > 0 ) simplifyDrawingHints |= QgsVectorLayer::AntialiasingSimplification;
+  }
+  settings.setValue( "/qgis/simplifyDrawingHints", simplifyDrawingHints );
+  settings.setValue( "/qgis/simplifyDrawingTol", 1.0f + 0.2f*mSimplifyDrawingSlider->value() );
+
   // project
   settings.setValue( "/qgis/projOpenAtLaunch", mProjectOnLaunchCmbBx->currentIndex() );
   settings.setValue( "/qgis/projOpenAtLaunchPath", mProjectOnLaunchLineEdit->text() );
@@ -2063,3 +2078,8 @@ void QgsOptions::saveDefaultDatumTransformations()
   s.endGroup();
 }
 
+void QgsOptions::on_mSimplifyDrawingSlider_valueChanged( int value )
+{
+  mSimplifyDrawingPanel->setVisible( value>0 );
+}
+

src/app/qgsoptions.h

@@ -235,6 +235,8 @@ class APP_EXPORT QgsOptions : public QgsOptionsDialogBase, private Ui::QgsOption
     void on_mRemoveDefaultTransformButton_clicked();
     void on_mAddDefaultTransformButton_clicked();
 
+    void on_mSimplifyDrawingSlider_valueChanged( int value );
+
   private:
     QStringList i18nList();
     void initContrastEnhancement( QComboBox *cbox, QString name, QString defaultVal );

src/app/qgsvectorlayerproperties.cpp

@@ -392,6 +392,11 @@ void QgsVectorLayerProperties::syncToLayer( void )
   cbMinimumScale->setScale( 1.0 / layer->minimumScale() );
   cbMaximumScale->setScale( 1.0 / layer->maximumScale() );
 
+  // get simplify drawing configuration
+  mSimplifyDrawingGroupBox->setChecked( layer->simplifyDrawingHints() != QgsVectorLayer::NoSimplification );
+  mSimplifyDrawingSlider->setValue( (int)(5.0f * (layer->simplifyDrawingTol()-1)) );
+  mSimplifyDrawingPanel->setVisible( mSimplifyDrawingSlider->value()>0 );
+
   // load appropriate symbology page (V1 or V2)
   updateSymbologyPage();
 
@@ -529,6 +534,16 @@ void QgsVectorLayerProperties::apply()
   layer->setMetadataUrlType( mLayerMetadataUrlTypeComboBox->currentText() );
   layer->setMetadataUrlFormat( mLayerMetadataUrlFormatComboBox->currentText() );
 
+  //layer simplify drawing configuration
+  int simplifyDrawingHints = QgsVectorLayer::NoSimplification;
+  if ( mSimplifyDrawingGroupBox->isChecked() )
+  {
+    simplifyDrawingHints |= QgsVectorLayer::DefaultSimplification;
+    if ( mSimplifyDrawingSlider->value() > 0 ) simplifyDrawingHints |= QgsVectorLayer::AntialiasingSimplification;
+  }
+  layer->setSimplifyDrawingHints( simplifyDrawingHints );
+  layer->setSimplifyDrawingTol( 1.0f + 0.2f*mSimplifyDrawingSlider->value() );
+
   // update symbology
   emit refreshLegend( layer->id(), QgsLegendItem::DontChange );
 
@@ -1067,3 +1082,8 @@ void QgsVectorLayerProperties::on_mMaximumScaleSetCurrentPushButton_clicked()
 {
   cbMaximumScale->setScale( 1.0 / QgisApp::instance()->mapCanvas()->mapRenderer()->scale() );
 }
+
+void QgsVectorLayerProperties::on_mSimplifyDrawingSlider_valueChanged( int value )
+{
+  mSimplifyDrawingPanel->setVisible( value>0 );
+}

src/app/qgsvectorlayerproperties.h

@@ -119,6 +119,8 @@ class APP_EXPORT QgsVectorLayerProperties : public QgsOptionsDialogBase, private
     void on_mMinimumScaleSetCurrentPushButton_clicked();
     void on_mMaximumScaleSetCurrentPushButton_clicked();
 
+    void on_mSimplifyDrawingSlider_valueChanged( int value );
+
   signals:
 
     /** emitted when changes to layer were saved to update legend */

src/core/CMakeLists.txt

@@ -74,6 +74,7 @@ SET(QGIS_CORE_SRCS
   qgsgeometry.cpp
   qgsgeometrycache.cpp
   qgsgeometryvalidator.cpp
+  qgsgeometrysimplifier.cpp
   qgsgml.cpp
   qgsgmlschema.cpp
   qgshttptransaction.cpp
@@ -85,6 +86,7 @@ SET(QGIS_CORE_SRCS
   qgsmaplayerregistry.cpp
   qgsmaprenderer.cpp
   qgsmaptopixel.cpp
+  qgsmaptopixelgeometrysimplifier.cpp
   qgsmessageoutput.cpp
   qgsmimedatautils.cpp
   qgsmessagelog.cpp

src/core/composer/qgscomposermap.cpp

@@ -199,13 +199,14 @@ void QgsComposerMap::draw( QPainter *painter, const QgsRectangle& extent, const
   {
     theRendererContext->setDrawEditingInformation( false );
     theRendererContext->setRenderingStopped( false );
-  }
+    theRendererContext->setRenderingPrintComposition( true );
 
-  // force vector output (no caching of marker images etc.)
-  theRendererContext->setForceVectorOutput( true );
+    // force vector output (no caching of marker images etc.)
+    theRendererContext->setForceVectorOutput( true );
 
-  // make the renderer respect the composition's useAdvancedEffects flag
-  theRendererContext->setUseAdvancedEffects( mComposition->useAdvancedEffects() );
+    // make the renderer respect the composition's useAdvancedEffects flag
+    theRendererContext->setUseAdvancedEffects( mComposition->useAdvancedEffects() );
+  }
 
   //force composer map scale for scale dependent visibility
   double bk_scale = theMapRenderer.scale();
@@ -315,7 +316,7 @@ void QgsComposerMap::paint( QPainter* painter, const QStyleOptionGraphicsItem* i
     drawBackground( painter );
     QFont messageFont( "", 12 );
     painter->setFont( messageFont );
-    painter->setPen( QColor( 0, 0, 0 ) );
+    painter->setPen( QColor( 0, 0, 0, 125 ) );
     painter->drawText( thisPaintRect, tr( "Map will be printed here" ) );
   }
   else if ( mComposition->plotStyle() == QgsComposition::Preview )
@@ -423,17 +424,16 @@ void QgsComposerMap::paint( QPainter* painter, const QStyleOptionGraphicsItem* i
   {
     drawGrid( painter );
   }
+  if ( mOverviewFrameMapId != -1 )
+  {
+    drawOverviewMapExtent( painter );
+  }
   drawFrame( painter );
   if ( isSelected() )
   {
     drawSelectionBoxes( painter );
   }
 
-  if ( mOverviewFrameMapId != -1 )
-  {
-    drawOverviewMapExtent( painter );
-  }
-
   painter->restore();
 }
 
@@ -2186,6 +2186,13 @@ void QgsComposerMap::drawOverviewMapExtent( QPainter* p )
     return;
   }
 
+  if ( mComposition->plotStyle() == QgsComposition::Preview && mPreviewMode == Rectangle )
+  {
+    //if map item is set to rectangle preview mode and we are not exporting the composition
+    //then don't draw an overview rectangle
+    return;
+  }
+
   const QgsComposerMap* overviewFrameMap = mComposition->getComposerMapById( mOverviewFrameMapId );
   if ( !overviewFrameMap )
   {
@@ -2199,15 +2206,8 @@ void QgsComposerMap::drawOverviewMapExtent( QPainter* p )
 
   QgsRenderContext context;
   context.setPainter( p );
-  if ( mPreviewMode == Rectangle )
-  {
-    return;
-  }
-  else
-  {
-    context.setScaleFactor( 1.0 );
-    context.setRasterScaleFactor( mComposition->printResolution() / 25.4 );
-  }
+  context.setScaleFactor( 1.0 );
+  context.setRasterScaleFactor( mComposition->printResolution() / 25.4 );
 
   p->save();
   p->setCompositionMode( mOverviewBlendMode );

src/core/qgis.cpp

@@ -73,6 +73,9 @@ const CORE_EXPORT QString GEO_NONE = "NONE";
 
 const double QGis::DEFAULT_IDENTIFY_RADIUS = 0.5;
 
+//! Default threshold between map coordinates and device coordinates for map2pixel simplification
+const float QGis::DEFAULT_MAPTOPIXEL_THRESHOLD = 1.0f;
+
 // description strings for units
 // Order must match enum indices
 const char* QGis::qgisUnitTypes[] =

src/core/qgis.h

@@ -263,6 +263,9 @@ class CORE_EXPORT QGis
 
     static const double DEFAULT_IDENTIFY_RADIUS;
 
+    //! Default threshold between map coordinates and device coordinates for map2pixel simplification
+    static const float DEFAULT_MAPTOPIXEL_THRESHOLD;
+
   private:
     // String representation of unit types (set in qgis.cpp)
     static const char *qgisUnitTypes[];

src/core/qgsclipper.cpp

@@ -45,6 +45,9 @@ const unsigned char* QgsClipper::clippedLineWKB( const unsigned char* wkb, const
 
   bool hasZValue = ( wkbType == QGis::WKBLineString25D );
 
+  int sizeOfDoubleX = sizeof(double);
+  int sizeOfDoubleY = hasZValue ? 2*sizeof(double) : sizeof(double);
+
   double p0x, p0y, p1x = 0.0, p1y = 0.0; //original coordinates
   double p1x_c, p1y_c; //clipped end coordinates
   double lastClipX = 0.0, lastClipY = 0.0; //last successfully clipped coords
@@ -56,29 +59,18 @@ const unsigned char* QgsClipper::clippedLineWKB( const unsigned char* wkb, const
   {
     if ( i == 0 )
     {
-      memcpy( &p1x, wkb, sizeof( double ) );
-      wkb += sizeof( double );
-      memcpy( &p1y, wkb, sizeof( double ) );
-      wkb += sizeof( double );
-      if ( hasZValue ) // ignore Z value
-      {
-        wkb += sizeof( double );
-      }
+      memcpy( &p1x, wkb, sizeof( double ) ); wkb += sizeOfDoubleX;
+      memcpy( &p1y, wkb, sizeof( double ) ); wkb += sizeOfDoubleY;
+
       continue;
     }
     else
     {
       p0x = p1x;
       p0y = p1y;
 
-      memcpy( &p1x, wkb, sizeof( double ) );
-      wkb += sizeof( double );
-      memcpy( &p1y, wkb, sizeof( double ) );
-      wkb += sizeof( double );
-      if ( hasZValue ) // ignore Z value
-      {
-        wkb += sizeof( double );
-      }
+      memcpy( &p1x, wkb, sizeof( double ) ); wkb += sizeOfDoubleX;
+      memcpy( &p1y, wkb, sizeof( double ) ); wkb += sizeOfDoubleY;
 
       p1x_c = p1x; p1y_c = p1y;
       if ( clipLineSegment( clipExtent.xMinimum(), clipExtent.xMaximum(), clipExtent.yMinimum(), clipExtent.yMaximum(),

src/core/qgscrscache.h

@@ -32,7 +32,10 @@ class CORE_EXPORT QgsCoordinateTransformCache
     ~QgsCoordinateTransformCache();
     /**Returns coordinate transformation. Cache keeps ownership
         @param srcAuthId auth id string of source crs
-        @param destAuthId auth id string of dest crs*/
+        @param destAuthId auth id string of dest crs
+        @param srcDatumTransform id of source's datum transform
+        @param destDatumTransform id of destinations's datum transform
+     */
     const QgsCoordinateTransform* transform( const QString& srcAuthId, const QString& destAuthId, int srcDatumTransform = -1, int destDatumTransform = -1 );
     /**Removes transformations where a changed crs is involved from the cache*/
     void invalidateCrs( const QString& crsAuthId );

src/core/qgsfeaturerequest.cpp

@@ -23,6 +23,9 @@ QgsFeatureRequest::QgsFeatureRequest()
     : mFilter( FilterNone )
     , mFilterExpression( 0 )
     , mFlags( 0 )
+    , mMapCoordTransform( NULL )
+    , mMapToPixel( NULL )
+    , mMapToPixelTol( QGis::DEFAULT_MAPTOPIXEL_THRESHOLD )
 {
 }
 
@@ -31,6 +34,9 @@ QgsFeatureRequest::QgsFeatureRequest( QgsFeatureId fid )
     , mFilterFid( fid )
     , mFilterExpression( 0 )
     , mFlags( 0 )
+    , mMapCoordTransform( NULL )
+    , mMapToPixel( NULL )
+    , mMapToPixelTol( QGis::DEFAULT_MAPTOPIXEL_THRESHOLD )
 {
 }
 
@@ -39,13 +45,19 @@ QgsFeatureRequest::QgsFeatureRequest( const QgsRectangle& rect )
     , mFilterRect( rect )
     , mFilterExpression( 0 )
     , mFlags( 0 )
+    , mMapCoordTransform( NULL )
+    , mMapToPixel( NULL )
+    , mMapToPixelTol( QGis::DEFAULT_MAPTOPIXEL_THRESHOLD )
 {
 }
 
 QgsFeatureRequest::QgsFeatureRequest( const QgsExpression& expr )
     : mFilter( FilterExpression )
     , mFilterExpression( new QgsExpression( expr.expression() ) )
     , mFlags( 0 )
+    , mMapCoordTransform( NULL )
+    , mMapToPixel( NULL )
+    , mMapToPixelTol( QGis::DEFAULT_MAPTOPIXEL_THRESHOLD )
 {
 }
 
@@ -70,6 +82,9 @@ QgsFeatureRequest& QgsFeatureRequest::operator=( const QgsFeatureRequest & rh )
     mFilterExpression = 0;
   }
   mAttrs = rh.mAttrs;
+  mMapCoordTransform = rh.mMapCoordTransform;
+  mMapToPixel = rh.mMapToPixel;
+  mMapToPixelTol = rh.mMapToPixelTol;
   return *this;
 }
 
@@ -174,3 +189,21 @@ bool QgsFeatureRequest::acceptFeature( const QgsFeature& feature )
 
   return true;
 }
+
+QgsFeatureRequest& QgsFeatureRequest::setCoordinateTransform( const QgsCoordinateTransform* ct ) 
+{
+  mMapCoordTransform = ct;
+  return *this;
+}
+
+QgsFeatureRequest& QgsFeatureRequest::setMapToPixel( const QgsMapToPixel* mtp ) 
+{
+  mMapToPixel = mtp;
+  return *this;
+}
+
+QgsFeatureRequest& QgsFeatureRequest::setMapToPixelTol( float map2pixelTol ) 
+{
+  mMapToPixelTol = map2pixelTol;
+  return *this;
+}