src/core/symbology-ng/qgssinglesymbolrendererv2.cpp

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#include "qgssinglesymbolrendererv2.h"

#include "qgssymbolv2.h"
#include "qgssymbollayerv2utils.h"

#include "qgslogger.h"
#include "qgsfeature.h"
#include "qgsvectorlayer.h"

#include <QDomDocument>
#include <QDomElement>

QgsSingleSymbolRendererV2::QgsSingleSymbolRendererV2( QgsSymbolV2* symbol )
    : QgsFeatureRendererV2( "singleSymbol" ), mRotationFieldIdx( -1 ), mSizeScaleFieldIdx( -1 ), mTempSymbol( NULL )
{
  Q_ASSERT( symbol );
  mSymbol = symbol;
}

QgsSingleSymbolRendererV2::~QgsSingleSymbolRendererV2()
{
  delete mSymbol;
}

QgsSymbolV2* QgsSingleSymbolRendererV2::symbolForFeature( QgsFeature& feature )
{
  if ( mRotationFieldIdx == -1 && mSizeScaleFieldIdx == -1 )
    return mSymbol;

  double rotation = 0;
  double sizeScale = 1;
  if ( mRotationFieldIdx != -1 )
  {
    rotation = feature.attributeMap()[mRotationFieldIdx].toDouble();
  }
  if ( mSizeScaleFieldIdx != -1 )
  {
    sizeScale = feature.attributeMap()[mSizeScaleFieldIdx].toDouble();
  }

  if ( mTempSymbol->type() == QgsSymbolV2::Marker )
  {
    QgsMarkerSymbolV2* markerSymbol = static_cast<QgsMarkerSymbolV2*>( mTempSymbol );
    if ( mRotationFieldIdx != -1 )
      markerSymbol->setAngle( rotation );
    if ( mSizeScaleFieldIdx != -1 )
      markerSymbol->setSize( sizeScale * mOrigSize );
  }
  else if ( mTempSymbol->type() == QgsSymbolV2::Line )
  {
    QgsLineSymbolV2* lineSymbol = static_cast<QgsLineSymbolV2*>( mTempSymbol );
    if ( mSizeScaleFieldIdx != -1 )
      lineSymbol->setWidth( sizeScale * mOrigSize );
  }
  else if ( mTempSymbol->type() == QgsSymbolV2::Fill )
  {
    QgsFillSymbolV2* fillSymbol = static_cast<QgsFillSymbolV2*>( mTempSymbol );
    if ( mRotationFieldIdx != -1 )
      fillSymbol->setAngle( rotation );
  }

  return mTempSymbol;
}

void QgsSingleSymbolRendererV2::startRender( QgsRenderContext& context, const QgsVectorLayer *vlayer )
{
  if ( !mSymbol )
  {
    return;
  }
  mRotationFieldIdx  = mRotationField.isEmpty()  ? -1 : vlayer->fieldNameIndex( mRotationField );
  mSizeScaleFieldIdx = mSizeScaleField.isEmpty() ? -1 : vlayer->fieldNameIndex( mSizeScaleField );

  mSymbol->startRender( context );

  if ( mRotationFieldIdx != -1 || mSizeScaleFieldIdx != -1 )
  {
    // we are going to need a temporary symbol
    mTempSymbol = mSymbol->clone();

    int hints = 0;
    if ( mRotationFieldIdx != -1 ) hints |= QgsSymbolV2::DataDefinedRotation;
    if ( mSizeScaleFieldIdx != -1 ) hints |= QgsSymbolV2::DataDefinedSizeScale;
    mTempSymbol->setRenderHints( hints );

    mTempSymbol->startRender( context );

    if ( mSymbol->type() == QgsSymbolV2::Marker )
    {
      mOrigSize = static_cast<QgsMarkerSymbolV2*>( mSymbol )->size();
    }
    else if ( mSymbol->type() == QgsSymbolV2::Line )
    {
      mOrigSize = static_cast<QgsLineSymbolV2*>( mSymbol )->width();
    }
    else
    {
      mOrigSize = 0;
    }
  }
}

void QgsSingleSymbolRendererV2::stopRender( QgsRenderContext& context )
{
  if ( !mSymbol )
  {
    return;
  }
  mSymbol->stopRender( context );

  if ( mRotationFieldIdx != -1 || mSizeScaleFieldIdx != -1 )
  {
    // we are going to need a temporary symbol
    mTempSymbol->stopRender( context );
    delete mTempSymbol;
    mTempSymbol = NULL;
  }
}

QList<QString> QgsSingleSymbolRendererV2::usedAttributes()
{
  QList<QString> lst;
  if ( !mRotationField.isEmpty() )
    lst.append( mRotationField );
  if ( !mSizeScaleField.isEmpty() )
    lst.append( mSizeScaleField );
  return lst;
}

QgsSymbolV2* QgsSingleSymbolRendererV2::symbol() const
{
  return mSymbol;
}

void QgsSingleSymbolRendererV2::setSymbol( QgsSymbolV2* s )
{
  Q_ASSERT( s );
  delete mSymbol;
  mSymbol = s;
}

QString QgsSingleSymbolRendererV2::dump()
{
  if ( mSymbol )
  {
    return QString( "SINGLE: %1" ).arg( mSymbol->dump() );
  }
  else
  {
    return "";
  }
}

QgsFeatureRendererV2* QgsSingleSymbolRendererV2::clone()
{
  QgsSingleSymbolRendererV2* r = new QgsSingleSymbolRendererV2( mSymbol->clone() );
  r->setUsingSymbolLevels( usingSymbolLevels() );
  r->setRotationField( rotationField() );
  r->setSizeScaleField( sizeScaleField() );
  return r;
}

QgsSymbolV2List QgsSingleSymbolRendererV2::symbols()
{
  QgsSymbolV2List lst;
  lst.append( mSymbol );
  return lst;
}

QgsFeatureRendererV2* QgsSingleSymbolRendererV2::create( QDomElement& element )
{
  QDomElement symbolsElem = element.firstChildElement( "symbols" );
  if ( symbolsElem.isNull() )
    return NULL;

  QgsSymbolV2Map symbolMap = QgsSymbolLayerV2Utils::loadSymbols( symbolsElem );

  if ( !symbolMap.contains( "0" ) )
    return NULL;

  QgsSingleSymbolRendererV2* r = new QgsSingleSymbolRendererV2( symbolMap.take( "0" ) );

  // delete symbols if there are any more
  QgsSymbolLayerV2Utils::clearSymbolMap( symbolMap );

  QDomElement rotationElem = element.firstChildElement( "rotation" );
  if ( !rotationElem.isNull() )
    r->setRotationField( rotationElem.attribute( "field" ) );

  QDomElement sizeScaleElem = element.firstChildElement( "sizescale" );
  if ( !sizeScaleElem.isNull() )
    r->setSizeScaleField( sizeScaleElem.attribute( "field" ) );

  // TODO: symbol levels
  return r;
}

QDomElement QgsSingleSymbolRendererV2::save( QDomDocument& doc )
{
  QDomElement rendererElem = doc.createElement( RENDERER_TAG_NAME );
  rendererElem.setAttribute( "type", "singleSymbol" );
  rendererElem.setAttribute( "symbollevels", ( mUsingSymbolLevels ? "1" : "0" ) );

  QgsSymbolV2Map symbols;
  symbols["0"] = mSymbol;
  QDomElement symbolsElem = QgsSymbolLayerV2Utils::saveSymbols( symbols, "symbols", doc );
  rendererElem.appendChild( symbolsElem );

  QDomElement rotationElem = doc.createElement( "rotation" );
  rotationElem.setAttribute( "field", mRotationField );
  rendererElem.appendChild( rotationElem );

  QDomElement sizeScaleElem = doc.createElement( "sizescale" );
  sizeScaleElem.setAttribute( "field", mSizeScaleField );
  rendererElem.appendChild( sizeScaleElem );

  return rendererElem;
}

QgsLegendSymbologyList QgsSingleSymbolRendererV2::legendSymbologyItems( QSize iconSize )
{
  QgsLegendSymbologyList lst;
  if ( mSymbol )
  {
    QPixmap pix = QgsSymbolLayerV2Utils::symbolPreviewPixmap( mSymbol, iconSize );
    lst << qMakePair( QString(), pix );
  }
  return lst;
}

QgsLegendSymbolList QgsSingleSymbolRendererV2::legendSymbolItems()
{
  QgsLegendSymbolList lst;
  lst << qMakePair( QString(), mSymbol );
  return lst;
}