Feature #8725: Simplification is assigned by flag

The drawing simplification can be configured using flags that indicates
what simplification type can be executed (Point, BBOX and AA)

Author: ahuarte47

src/app/qgsvectorlayerproperties.cpp

@@ -393,7 +393,7 @@ void QgsVectorLayerProperties::syncToLayer( void )
   cbMaximumScale->setScale( 1.0 / layer->maximumScale() );
 
   // get simplify drawing configuration
-  mSimplifyDrawingGroupBox->setChecked( layer->simplifyDrawing() );
+  mSimplifyDrawingGroupBox->setChecked( layer->simplifyDrawingHints() != QgsVectorLayer::NoSimplification );
   mSimplifyDrawingSlider->setValue( (int)(5.0f * (layer->simplifyDrawingTol()-1)) );
 
   // load appropriate symbology page (V1 or V2)
@@ -534,7 +534,7 @@ void QgsVectorLayerProperties::apply()
   layer->setMetadataUrlFormat( mLayerMetadataUrlFormatComboBox->currentText() );
 
   //layer simplify drawing configuration
-  layer->setSimplifyDrawing( mSimplifyDrawingGroupBox->isChecked() );
+  layer->setSimplifyDrawingHints( mSimplifyDrawingGroupBox->isChecked() ? QgsVectorLayer::FullSimplification : QgsVectorLayer::NoSimplification );
   layer->setSimplifyDrawingTol( 1.0f + 0.2f*mSimplifyDrawingSlider->value() );
 
   // update symbology

src/core/qgsfeaturerequest.cpp

@@ -379,18 +379,19 @@ inline static bool generalizeGeometry( QGis::WkbType wkbType, unsigned char* sou
 }
 
 //! Simplify the WKB-geometry using the specified tolerance
-inline static bool simplifyWkbGeometry( QGis::WkbType wkbType, unsigned char* sourceWkb, size_t sourceWkbSize, unsigned char* targetWkb, size_t& targetWkbSize, const QgsRectangle& envelope, float map2pixelTol, bool writeHeader = true, bool isaLinearRing = false )
+inline static bool simplifyWkbGeometry( const QgsFeatureRequest::Flags& requestFlags, QGis::WkbType wkbType, unsigned char* sourceWkb, size_t sourceWkbSize, unsigned char* targetWkb, size_t& targetWkbSize, const QgsRectangle& envelope, float map2pixelTol, bool writeHeader = true, bool isaLinearRing = false )
 {
   bool canbeGeneralizable = true;
   bool hasZValue = QGis::wkbDimensions(wkbType)==3;
   bool result = false;
 
   // Can replace the geometry by its BBOX ?
-  if ( (envelope.xMaximum()-envelope.xMinimum()) < map2pixelTol && (envelope.yMaximum()-envelope.yMinimum()) < map2pixelTol )
+  if ( ( requestFlags & QgsFeatureRequest::SimplifyEnvelope ) && (envelope.xMaximum()-envelope.xMinimum()) < map2pixelTol && (envelope.yMaximum()-envelope.yMinimum()) < map2pixelTol )
   {
     canbeGeneralizable = generalizeGeometry( wkbType, sourceWkb, sourceWkbSize, targetWkb, targetWkbSize, envelope, writeHeader );
     if (canbeGeneralizable) return true;
   }
+  if (!( requestFlags & QgsFeatureRequest::SimplifyGeometry ) ) canbeGeneralizable = false;
 
   // Write the main header of the geometry
   if ( writeHeader )
@@ -484,7 +485,7 @@ inline static bool simplifyWkbGeometry( QGis::WkbType wkbType, unsigned char* so
       size_t sourceWkbSize_i = 4 + numPoints_i * (hasZValue ? 3 : 2) * sizeof(double);
       size_t targetWkbSize_i = 0;
 
-      result |= simplifyWkbGeometry( wkbType, sourceWkb, sourceWkbSize_i, targetWkb, targetWkbSize_i, envelope_i, map2pixelTol, false, true );
+      result |= simplifyWkbGeometry( requestFlags, wkbType, sourceWkb, sourceWkbSize_i, targetWkb, targetWkbSize_i, envelope_i, map2pixelTol, false, true );
       sourceWkb += sourceWkbSize_i;
       targetWkb += targetWkbSize_i;
 
@@ -535,7 +536,7 @@ inline static bool simplifyWkbGeometry( QGis::WkbType wkbType, unsigned char* so
           wkb1 += wkbSize_i;
         }
       }
-      result |= simplifyWkbGeometry( QGis::singleType(wkbType), sourceWkb, sourceWkbSize_i, targetWkb, targetWkbSize_i, envelope, map2pixelTol, true, false );
+      result |= simplifyWkbGeometry( requestFlags, QGis::singleType(wkbType), sourceWkb, sourceWkbSize_i, targetWkb, targetWkbSize_i, envelope, map2pixelTol, true, false );
       sourceWkb += sourceWkbSize_i;
       targetWkb += targetWkbSize_i;
 
@@ -573,7 +574,7 @@ bool QgsFeatureRequest::canbeGeneralizedByMapBoundingBox( const QgsRectangle& en
 }
 
 //! Simplify the specified geometry (Removing duplicated points) when is applied the map2pixel context
-bool QgsFeatureRequest::simplifyGeometry( QgsGeometry* geometry, const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol )
+bool QgsFeatureRequest::simplifyGeometry( const QgsFeatureRequest::Flags& requestFlags, QgsGeometry* geometry, const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol )
 {
   size_t targetWkbSize = 0;
 
@@ -589,7 +590,7 @@ bool QgsFeatureRequest::simplifyGeometry( QgsGeometry* geometry, const QgsCoordi
   size_t wkbSize = geometry->wkbSize( );
 
   // Simplify the geometry rewriting temporally its WKB-stream for saving calloc's.
-  if ( simplifyWkbGeometry( wkbType, wkb, wkbSize, wkb, targetWkbSize, envelope, map2pixelTol ) )
+  if ( simplifyWkbGeometry( requestFlags, wkbType, wkb, wkbSize, wkb, targetWkbSize, envelope, map2pixelTol ) )
   {
     unsigned char* targetWkb = (unsigned char*)malloc( targetWkbSize );
     memcpy( targetWkb, wkb, targetWkbSize );
@@ -600,8 +601,10 @@ bool QgsFeatureRequest::simplifyGeometry( QgsGeometry* geometry, const QgsCoordi
 }
 
 //! Simplify the specified point stream (Removing duplicated points) when is applied the map2pixel context
-bool QgsFeatureRequest::simplifyGeometry( QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount, const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol )
+bool QgsFeatureRequest::simplifyGeometry( const QgsFeatureRequest::Flags& requestFlags, QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount, const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol )
 {
+  bool canbeGeneralizable = ( requestFlags & QgsFeatureRequest::SimplifyGeometry );
+
   pointSimplifiedCount = pointCount;
   if ( geometryType == QGis::Point || geometryType == QGis::UnknownGeometry ) return false;
   pointSimplifiedCount = 0;
@@ -620,7 +623,7 @@ bool QgsFeatureRequest::simplifyGeometry( QGis::GeometryType geometryType, const
     memcpy( &x, xsourcePtr, sizeof( double ) ); xsourcePtr += xStride;
     memcpy( &y, ysourcePtr, sizeof( double ) ); ysourcePtr += yStride;
 
-    if ( i==0 || calculateLengthSquared2D(x,y,lastX,lastY)>map2pixelTol )
+    if ( i==0 || !canbeGeneralizable || calculateLengthSquared2D(x,y,lastX,lastY)>map2pixelTol )
     {
       memcpy( xtargetPtr, &x, sizeof( double ) ); lastX = x; xtargetPtr += xStride;
       memcpy( ytargetPtr, &y, sizeof( double ) ); lastY = y; ytargetPtr += yStride;

src/core/qgsfeaturerequest.h

@@ -65,7 +65,8 @@ class CORE_EXPORT QgsFeatureRequest
       NoGeometry         = 1,  //!< Geometry is not required. It may still be returned if e.g. required for a filter condition.
       SubsetOfAttributes = 2,  //!< Fetch only a subset of attributes (setSubsetOfAttributes sets this flag)
       ExactIntersect     = 4,  //!< Use exact geometry intersection (slower) instead of bounding boxes
-      SimplifyGeometries = 8   //!< Simplify the geometry using the current map2pixel context (e.g. for fast rendering...)
+      SimplifyGeometry   = 8,  //!< The geometries can be simplified using the current map2pixel context state (e.g. for fast rendering...)
+      SimplifyEnvelope   = 16  //!< The geometries can be fully simplified by its BoundingBox (e.g. for fast rendering...)
     };
     Q_DECLARE_FLAGS( Flags, Flag )
 
@@ -182,18 +183,21 @@ class CORE_EXPORT QgsFeatureRequest
     inline bool canbeGeneralizedByMapBoundingBox( const QgsRectangle& envelope ) const { return canbeGeneralizedByMapBoundingBox( envelope, mMapCoordTransform, mMapToPixel, mMapToPixelTol ); }
 
     //! Simplify the specified geometry (Removing duplicated points) when is applied the map2pixel context
-    static bool simplifyGeometry( QgsGeometry* geometry, 
+    static bool simplifyGeometry( const QgsFeatureRequest::Flags& requestFlags, 
+                                  QgsGeometry* geometry, 
                                   const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol = 1.0f );
 
     //! Simplify the specified geometry (Removing duplicated points) when is applied the map2pixel context
-    inline bool simplifyGeometry( QgsGeometry* geometry ) const { return simplifyGeometry( geometry, mMapCoordTransform, mMapToPixel, mMapToPixelTol ); }
+    inline bool simplifyGeometry( QgsGeometry* geometry ) const { return simplifyGeometry( mFlags, geometry, mMapCoordTransform, mMapToPixel, mMapToPixelTol ); }
 
     //! Simplify the specified point stream (Removing duplicated points) when is applied a map2pixel context
-    static bool simplifyGeometry( QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount,
+    static bool simplifyGeometry( const QgsFeatureRequest::Flags& requestFlags, 
+                                  QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount,
                                   const QgsCoordinateTransform* coordinateTransform, const QgsMapToPixel* mtp, float mapToPixelTol = 1.0f );
 
     //! Simplify the specified point stream (Removing duplicated points) when is applied the map2pixel context
-    inline bool simplifyGeometry( QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount ) const { return simplifyGeometry( geometryType, envelope, xptr, xStride, yptr, yStride, pointCount, pointSimplifiedCount, mMapCoordTransform, mMapToPixel, mMapToPixelTol ); }
+    inline bool simplifyGeometry( const QgsFeatureRequest::Flags& requestFlags, 
+                                  QGis::GeometryType geometryType, const QgsRectangle& envelope, double* xptr, int xStride, double* yptr, int yStride, int pointCount, int& pointSimplifiedCount ) const { return simplifyGeometry( requestFlags, geometryType, envelope, xptr, xStride, yptr, yStride, pointCount, pointSimplifiedCount, mMapCoordTransform, mMapToPixel, mMapToPixelTol ); }
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS( QgsFeatureRequest::Flags )

src/core/qgsvectorlayer.cpp

@@ -136,7 +136,7 @@ QgsVectorLayer::QgsVectorLayer( QString vectorLayerPath,
     , mSymbolFeatureCounted( false )
     , mCurrentRendererContext( 0 )
     , mSimplifyDrawingTol( QgsFeatureRequest::MAPTOPIXEL_THRESHOLD_DEFAULT )
-    , mSimplifyDrawing( true )
+    , mSimplifyDrawingHints( QgsVectorLayer::FullSimplification )
 
 {
   mActions = new QgsAttributeAction( this );
@@ -693,13 +693,17 @@ bool QgsVectorLayer::draw( QgsRenderContext& rendererContext )
                                      .setFilterRect( rendererContext.extent() )
                                      .setSubsetOfAttributes( attributes );
 
-  // Enable the simplification of the geometries before fetch the features using the current map2pixel context.
-  if ( simplifyDrawingCanbeApplied() && !(featureRequest.flags() & QgsFeatureRequest::NoGeometry) && !rendererContext.renderingPrintComposition() )
+  // Enable the simplification of the geometries (Using the current map2pixel context) before fetch the features.
+  if ( simplifyDrawingCanbeApplied( QgsVectorLayer::GeometrySimplification | QgsVectorLayer::EnvelopeSimplification ) && !(featureRequest.flags() & QgsFeatureRequest::NoGeometry) && !rendererContext.renderingPrintComposition() )
   {
+    QgsFeatureRequest::Flags simplificationHints = QgsFeatureRequest::NoFlags;
+    if ( mSimplifyDrawingHints & QgsVectorLayer::GeometrySimplification ) simplificationHints |= QgsFeatureRequest::SimplifyGeometry;
+    if ( mSimplifyDrawingHints & QgsVectorLayer::EnvelopeSimplification ) simplificationHints |= QgsFeatureRequest::SimplifyEnvelope;
+
     QPainter* p = rendererContext.painter();
     float dpi = ( p->device()->logicalDpiX() + p->device()->logicalDpiY() ) / 2;
 
-    featureRequest.setFlags( featureRequest.flags() | QgsFeatureRequest::SimplifyGeometries );
+    featureRequest.setFlags( featureRequest.flags() | simplificationHints );
     featureRequest.setCoordinateTransform( rendererContext.coordinateTransform() );
     featureRequest.setMapToPixel( &rendererContext.mapToPixel() );
     featureRequest.setMapToPixelTol( mSimplifyDrawingTol * 96.0f/dpi );
@@ -1221,13 +1225,17 @@ bool QgsVectorLayer::setSubsetString( QString subset )
   return res;
 }
 
+bool QgsVectorLayer::simplifyDrawingCanbeApplied( int simplifyHint ) const 
+{
+  return ( mSimplifyDrawingHints & simplifyHint ) && !mEditBuffer && ( !mCurrentRendererContext || !mCurrentRendererContext->renderingPrintComposition() ); 
+}
 
 QgsFeatureIterator QgsVectorLayer::getFeatures( const QgsFeatureRequest& request )
 {
   if ( !mDataProvider )
     return QgsFeatureIterator();
 
-  if ( mSimplifyDrawing && (request.flags() & QgsFeatureRequest::SimplifyGeometries) && !(request.flags() & QgsFeatureRequest::NoGeometry) )
+  if ( request.flags() & ( QgsFeatureRequest::SimplifyGeometry | QgsFeatureRequest::SimplifyEnvelope ) && !( request.flags() & QgsFeatureRequest::NoGeometry ) )
     return QgsFeatureIterator( new QgsSimplifiedVectorLayerFeatureIterator( this, request ) );
 
   return QgsFeatureIterator( new QgsVectorLayerFeatureIterator( this, request ) );
@@ -1834,7 +1842,7 @@ bool QgsVectorLayer::readSymbology( const QDomNode& node, QString& errorMessage
     mLabel->setMaxScale( e.attribute( "maxLabelScale", "100000000" ).toFloat() );
 
     // get the simplification drawing configuration
-    setSimplifyDrawing( e.attribute( "simplifyDrawingFlag", "1" ) == "1" );
+    setSimplifyDrawingHints( e.attribute( "simplifyDrawingHints", "7" ).toInt() );
     setSimplifyDrawingTol( e.attribute( "simplifyDrawingTol", "1" ).toFloat() );
 
     //also restore custom properties (for labeling-ng)
@@ -2171,7 +2179,7 @@ bool QgsVectorLayer::writeSymbology( QDomNode& node, QDomDocument& doc, QString&
     mapLayerNode.setAttribute( "maxLabelScale", QString::number( mLabel->maxScale() ) );
 
     // save the simplification drawing configuration
-    mapLayerNode.setAttribute( "simplifyDrawingFlag", mSimplifyDrawing ? 1 : 0 );
+    mapLayerNode.setAttribute( "simplifyDrawingHints", QString::number( mSimplifyDrawingHints ) );
     mapLayerNode.setAttribute( "simplifyDrawingTol", QString::number( mSimplifyDrawingTol ) );
 
     //save customproperties (for labeling ng)

src/core/qgsvectorlayer.h

@@ -1369,13 +1369,22 @@ class CORE_EXPORT QgsVectorLayer : public QgsMapLayer
     /** Returns the Map2pixel simplification threshold for fast rendering of features */
     float simplifyDrawingTol() const { return mSimplifyDrawingTol; }
 
-    /** Enable the Map2pixel simplification for fast rendering of features */
-    void setSimplifyDrawing( bool simplifyDrawing ) { mSimplifyDrawing = simplifyDrawing; }
-    /** Returns whether is enabled the map2pixel simplification of geometries for fast rendering of features */
-    bool simplifyDrawing() const { return mSimplifyDrawing; }
+    /** Simplification flags for fast rendering of features */
+    enum SimplifyHint
+    {
+      NoSimplification           = 0, //!< No simplification can be applied
+      GeometrySimplification     = 1, //!< The geometries can be simplified using the current map2pixel context state
+      EnvelopeSimplification     = 2, //!< The geometries can be fully simplified by its BoundingBox using the current map2pixel context state
+      AntialiasingSimplification = 4, //!< The geometries can be rendered with 'AntiAliasing' disabled because of it is '1-pixel size'
+      FullSimplification         = 7, //!< All simplification hints can be applied
+    };
+    /** Set the Map2pixel simplification hints for fast rendering of features */
+    void setSimplifyDrawingHints( int simplifyDrawingHints ) { mSimplifyDrawingHints = simplifyDrawingHints; }
+    /** Returns the Map2pixel simplification hints for fast rendering of features */
+    int simplifyDrawingHints() const { return mSimplifyDrawingHints; }
 
-    /** Returns whether the VectorLayer can apply geometry simplification in FeatureRequests */
-    bool simplifyDrawingCanbeApplied() const { return mSimplifyDrawing && !mEditBuffer && ( !mCurrentRendererContext || !mCurrentRendererContext->renderingPrintComposition() ); }
+    /** Returns whether the VectorLayer can apply the specified simplification hint */
+    bool simplifyDrawingCanbeApplied( int simplifyHint ) const;
 
   public slots:
     /**
@@ -1646,10 +1655,10 @@ class CORE_EXPORT QgsVectorLayer : public QgsMapLayer
     /** Renderer object which holds the information about how to display the features */
     QgsFeatureRendererV2 *mRendererV2;
 
-    /** Map2pixel simplification threshold for fast rendering of features */
+    /** Map2pixel geometry simplification threshold for fast rendering of features */
     float mSimplifyDrawingTol;
-    /** Enable map2pixel simplification of geometries for fast rendering of features */
-    bool mSimplifyDrawing;
+    /** Map2pixel geometry simplification hints for fast rendering of features */
+    int mSimplifyDrawingHints;
 
     /** Label */
     QgsLabel *mLabel;

src/core/symbology-ng/qgslinesymbollayerv2.cpp

@@ -181,7 +181,7 @@ void QgsSimpleLineSymbolLayerV2::renderPolyline( const QPolygonF& points, QgsSym
   p->setPen( context.selected() ? mSelPen : mPen );
 
   // Disable 'Antialiasing' if the geometry was generalized in the current RenderContext (We known that it must have least #2 points).
-  if ( points.size()<=2 && context.layer() && context.layer()->simplifyDrawingCanbeApplied() && QgsFeatureRequest::canbeGeneralizedByWndBoundingBox( points, context.layer()->simplifyDrawingTol() ) && p->renderHints() & QPainter::Antialiasing )
+  if ( points.size()<=2 && context.layer() && context.layer()->simplifyDrawingCanbeApplied( QgsVectorLayer::AntialiasingSimplification ) && QgsFeatureRequest::canbeGeneralizedByWndBoundingBox( points, context.layer()->simplifyDrawingTol() ) && p->renderHints() & QPainter::Antialiasing )
   {
     p->setRenderHint( QPainter::Antialiasing, false );
     p->drawPolyline( points );

src/core/symbology-ng/qgssymbollayerv2.cpp

@@ -358,7 +358,7 @@ void QgsFillSymbolLayerV2::_renderPolygon( QPainter* p, const QPolygonF& points,
   }
 
   // Disable 'Antialiasing' if the geometry was generalized in the current RenderContext (We known that it must have least #5 points).
-  if ( points.size()<=5 && context.layer() && context.layer()->simplifyDrawingCanbeApplied() && QgsFeatureRequest::canbeGeneralizedByWndBoundingBox( points, context.layer()->simplifyDrawingTol() ) && p->renderHints() & QPainter::Antialiasing )
+  if ( points.size()<=5 && context.layer() && context.layer()->simplifyDrawingCanbeApplied( QgsVectorLayer::AntialiasingSimplification ) && QgsFeatureRequest::canbeGeneralizedByWndBoundingBox( points, context.layer()->simplifyDrawingTol() ) && p->renderHints() & QPainter::Antialiasing )
   {
     p->setRenderHint( QPainter::Antialiasing, false );
     p->drawConvexPolygon( points );