Exemple #1
0
static QString _getLayerSvgMarkerPath( const QgsProject &prj, const QString &layerName )
{
  QList<QgsMapLayer *> layers = prj.mapLayersByName( layerName );
  Q_ASSERT( layers.count() == 1 );
  Q_ASSERT( layers[0]->type() == QgsMapLayerType::VectorLayer );
  QgsVectorLayer *layer = qobject_cast<QgsVectorLayer *>( layers[0] );
  Q_ASSERT( layer->renderer() );
  Q_ASSERT( layer->renderer()->type() == "singleSymbol" );
  QgsSingleSymbolRenderer *r = static_cast<QgsSingleSymbolRenderer *>( layer->renderer() );
  QgsSymbol *s = r->symbol();
  Q_ASSERT( s && s->symbolLayerCount() == 1 );
  Q_ASSERT( s->symbolLayer( 0 )->layerType() == "SvgMarker" );
  QgsSvgMarkerSymbolLayer *sl = static_cast<QgsSvgMarkerSymbolLayer *>( s->symbolLayer( 0 ) );
  return sl->path();
}
void QgsVectorLayerRenderer::drawRendererLevels( QgsFeatureIterator &fit )
{
  QHash< QgsSymbol *, QList<QgsFeature> > features; // key = symbol, value = array of features

  QgsSingleSymbolRenderer *selRenderer = nullptr;
  if ( !mSelectedFeatureIds.isEmpty() )
  {
    selRenderer = new QgsSingleSymbolRenderer( QgsSymbol::defaultSymbol( mGeometryType ) );
    selRenderer->symbol()->setColor( mContext.selectionColor() );
    selRenderer->setVertexMarkerAppearance( mVertexMarkerStyle, mVertexMarkerSize );
    selRenderer->startRender( mContext, mFields );
  }

  QgsExpressionContextScope *symbolScope = QgsExpressionContextUtils::updateSymbolScope( nullptr, new QgsExpressionContextScope() );
  mContext.expressionContext().appendScope( symbolScope );

  // 1. fetch features
  QgsFeature fet;
  while ( fit.nextFeature( fet ) )
  {
    if ( mContext.renderingStopped() )
    {
      qDebug( "rendering stop!" );
      stopRenderer( selRenderer );
      delete mContext.expressionContext().popScope();
      return;
    }

    if ( !fet.hasGeometry() )
      continue; // skip features without geometry

    mContext.expressionContext().setFeature( fet );
    QgsSymbol *sym = mRenderer->symbolForFeature( fet, mContext );
    if ( !sym )
    {
      continue;
    }

    if ( !features.contains( sym ) )
    {
      features.insert( sym, QList<QgsFeature>() );
    }
    features[sym].append( fet );

    // new labeling engine
    if ( mContext.labelingEngine() )
    {
      QgsGeometry obstacleGeometry;
      QgsSymbolList symbols = mRenderer->originalSymbolsForFeature( fet, mContext );

      if ( !symbols.isEmpty() && fet.geometry().type() == QgsWkbTypes::PointGeometry )
      {
        obstacleGeometry = QgsVectorLayerLabelProvider::getPointObstacleGeometry( fet, mContext, symbols );
      }

      if ( !symbols.isEmpty() )
      {
        QgsExpressionContextUtils::updateSymbolScope( symbols.at( 0 ), symbolScope );
      }

      if ( mLabelProvider )
      {
        mLabelProvider->registerFeature( fet, mContext, obstacleGeometry );
      }
      if ( mDiagramProvider )
      {
        mDiagramProvider->registerFeature( fet, mContext, obstacleGeometry );
      }
    }
  }

  delete mContext.expressionContext().popScope();

  if ( features.empty() )
  {
    // nothing to draw
    stopRenderer( selRenderer );
    return;
  }

  // find out the order
  QgsSymbolLevelOrder levels;
  QgsSymbolList symbols = mRenderer->symbols( mContext );
  for ( int i = 0; i < symbols.count(); i++ )
  {
    QgsSymbol *sym = symbols[i];
    for ( int j = 0; j < sym->symbolLayerCount(); j++ )
    {
      int level = sym->symbolLayer( j )->renderingPass();
      if ( level < 0 || level >= 1000 ) // ignore invalid levels
        continue;
      QgsSymbolLevelItem item( sym, j );
      while ( level >= levels.count() ) // append new empty levels
        levels.append( QgsSymbolLevel() );
      levels[level].append( item );
    }
  }

  // 2. draw features in correct order
  for ( int l = 0; l < levels.count(); l++ )
  {
    QgsSymbolLevel &level = levels[l];
    for ( int i = 0; i < level.count(); i++ )
    {
      QgsSymbolLevelItem &item = level[i];
      if ( !features.contains( item.symbol() ) )
      {
        QgsDebugMsg( QStringLiteral( "level item's symbol not found!" ) );
        continue;
      }
      int layer = item.layer();
      QList<QgsFeature> &lst = features[item.symbol()];
      QList<QgsFeature>::iterator fit;
      for ( fit = lst.begin(); fit != lst.end(); ++fit )
      {
        if ( mContext.renderingStopped() )
        {
          stopRenderer( selRenderer );
          return;
        }

        bool sel = mContext.showSelection() && mSelectedFeatureIds.contains( fit->id() );
        // maybe vertex markers should be drawn only during the last pass...
        bool drawMarker = ( mDrawVertexMarkers && mContext.drawEditingInformation() && ( !mVertexMarkerOnlyForSelection || sel ) );

        mContext.expressionContext().setFeature( *fit );

        try
        {
          mRenderer->renderFeature( *fit, mContext, layer, sel, drawMarker );
        }
        catch ( const QgsCsException &cse )
        {
          Q_UNUSED( cse );
          QgsDebugMsg( QStringLiteral( "Failed to transform a point while drawing a feature with ID '%1'. Ignoring this feature. %2" )
                       .arg( fet.id() ).arg( cse.what() ) );
        }
      }
    }
  }

  stopRenderer( selRenderer );
}