qgsrubberband.cpp

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/***************************************************************************
    qgsrubberband.cpp - Rubberband widget for drawing multilines and polygons
     --------------------------------------
    Date                 : 07-Jan-2006
    Copyright            : (C) 2006 by Tom Elwertowski
    Email                : telwertowski at users dot sourceforge dot net
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
 
#include "qgsrubberband.h"
 
#include "qgsfillsymbol.h"
#include "qgsgeometry.h"
#include "qgsguiutils.h"
#include "qgslinesymbol.h"
#include "qgslogger.h"
#include "qgsmapcanvas.h"
#include "qgspainting.h"
#include "qgsproject.h"
#include "qgsrectangle.h"
#include "qgsrendercontext.h"
#include "qgssymbol.h"
#include "qgsvectorlayer.h"
 
#include <QPainter>
#include <QString>
 
#include "moc_qgsrubberband.cpp"
 
using namespace Qt::StringLiterals;
 
QgsRubberBand::QgsRubberBand( QgsMapCanvas *mapCanvas, Qgis::GeometryType geometryType )
  : QObject( nullptr )
  , QgsMapCanvasItem( mapCanvas )
  , mGeometryType( geometryType )
{
  reset( geometryType );
  QColor color( Qt::lightGray );
  color.setAlpha( 63 );
  setColor( color );
  setWidth( 1 );
  setLineStyle( Qt::SolidLine );
  setBrushStyle( Qt::SolidPattern );
  setSecondaryStrokeColor( QColor() );
}
 
QgsRubberBand::QgsRubberBand()
  : QObject( nullptr )
  , QgsMapCanvasItem( nullptr )
{}
 
QgsRubberBand::~QgsRubberBand() = default;
 
void QgsRubberBand::setColor( const QColor &color )
{
  setStrokeColor( color );
  setFillColor( color );
}
 
void QgsRubberBand::setFillColor( const QColor &color )
{
  if ( mBrush.color() == color )
    return;
 
  mBrush.setColor( color );
}
 
void QgsRubberBand::setStrokeColor( const QColor &color )
{
  mPen.setColor( color );
}
 
void QgsRubberBand::setSecondaryStrokeColor( const QColor &color )
{
  mSecondaryPen.setColor( color );
}
 
void QgsRubberBand::setWidth( double width )
{
  mPen.setWidthF( width );
}
 
void QgsRubberBand::setIcon( Qgis::RubberBandIconType icon )
{
  mIconType = icon;
}
 
void QgsRubberBand::setSvgIcon( const QString &path, QPoint drawOffset )
{
  setIcon( Qgis::RubberBandIconType::SVG );
  mSvgRenderer = std::make_unique<QSvgRenderer>( path );
  mSvgOffset = drawOffset;
}
 
void QgsRubberBand::setIconSize( double iconSize )
{
  mIconSize = iconSize;
}
 
void QgsRubberBand::setLineStyle( Qt::PenStyle penStyle )
{
  mPen.setStyle( penStyle );
}
 
void QgsRubberBand::setBrushStyle( Qt::BrushStyle brushStyle )
{
  mBrush.setStyle( brushStyle );
}
 
void QgsRubberBand::reset( Qgis::GeometryType geometryType )
{
  mPoints.clear();
  mGeometryType = geometryType;
  updateRect();
  update();
}
 
void QgsRubberBand::addPreviewItem( QgsRubberBandPreviewItem *item )
{
  if ( item )
  {
    mPreviewItems.push_back( std::unique_ptr< QgsRubberBandPreviewItem>( item ) );
    update();
  }
}
 
void QgsRubberBand::clearPreviewItems()
{
  mPreviewItems.clear();
  update();
}
 
void QgsRubberBand::addPoint( const QgsPointXY &p, bool doUpdate /* = true */, int geometryIndex, int ringIndex )
{
  if ( geometryIndex < 0 )
  {
    geometryIndex = mPoints.size() - 1;
  }
 
  if ( geometryIndex < 0 || geometryIndex > mPoints.size() )
  {
    return;
  }
 
  if ( geometryIndex == mPoints.size() )
  {
    // since we're adding a geometry, ringIndex must be 0 or negative for last ring
    if ( ringIndex > 0 )
      return;
    mPoints.append( QgsPolygonXY() );
  }
 
  // negative ringIndex means last ring
  if ( ringIndex < 0 )
  {
    if ( mPoints.at( geometryIndex ).isEmpty() )
      ringIndex = 0;
    else
      ringIndex = mPoints.at( geometryIndex ).size() - 1;
  }
 
  if ( ringIndex > mPoints.at( geometryIndex ).size() )
    return;
 
  if ( ringIndex == mPoints.at( geometryIndex ).size() )
  {
    mPoints[geometryIndex].append( QgsPolylineXY() );
    if ( mGeometryType != Qgis::GeometryType::Point )
      mPoints[geometryIndex][ringIndex].append( p );
  }
 
  if ( mPoints.at( geometryIndex ).at( ringIndex ).size() == 2 && mPoints.at( geometryIndex ).at( ringIndex ).at( 0 ) == mPoints.at( geometryIndex ).at( ringIndex ).at( 1 ) )
  {
    mPoints[geometryIndex][ringIndex].last() = p;
  }
  else
  {
    mPoints[geometryIndex][ringIndex].append( p );
  }
 
 
  if ( doUpdate )
  {
    setVisible( true );
    updateRect();
    update();
  }
}
 
void QgsRubberBand::closePoints( bool doUpdate, int geometryIndex, int ringIndex )
{
  if ( geometryIndex < 0 || ringIndex < 0 || mPoints.size() <= geometryIndex || mPoints.at( geometryIndex ).size() <= ringIndex || mPoints.at( geometryIndex ).at( ringIndex ).isEmpty() )
  {
    return;
  }
 
  if ( mPoints.at( geometryIndex ).at( ringIndex ).constFirst() != mPoints.at( geometryIndex ).at( ringIndex ).constLast() )
  {
    mPoints[geometryIndex][ringIndex].append( mPoints.at( geometryIndex ).at( ringIndex ).constFirst() );
  }
 
  if ( doUpdate )
  {
    setVisible( true );
    updateRect();
    update();
  }
}
 
 
void QgsRubberBand::removePoint( int index, bool doUpdate /* = true*/, int geometryIndex /* = 0*/, int ringIndex /* = 0*/ )
{
  if ( geometryIndex < 0
       || ringIndex < 0
       || mPoints.size() <= geometryIndex
       || mPoints.at( geometryIndex ).size() <= ringIndex
       || mPoints.at( geometryIndex ).at( ringIndex ).size() <= index
       || mPoints.at( geometryIndex ).at( ringIndex ).size() < -index
       || mPoints.at( geometryIndex ).at( ringIndex ).isEmpty() )
  {
    return;
  }
 
  // negative index removes from end, e.g., -1 removes last one
  if ( index < 0 )
  {
    index = mPoints.at( geometryIndex ).at( ringIndex ).size() + index;
  }
  mPoints[geometryIndex][ringIndex].removeAt( index );
 
  if ( doUpdate )
  {
    updateRect();
    update();
  }
}
 
void QgsRubberBand::removeLastPoint( int geometryIndex, bool doUpdate /* = true*/, int ringIndex /* = 0*/ )
{
  removePoint( -1, doUpdate, geometryIndex, ringIndex );
}
 
void QgsRubberBand::movePoint( const QgsPointXY &p, int geometryIndex, int ringIndex )
{
  if ( geometryIndex < 0 || ringIndex < 0 || mPoints.size() <= geometryIndex || mPoints.at( geometryIndex ).size() <= ringIndex || mPoints.at( geometryIndex ).at( ringIndex ).isEmpty() )
  {
    return;
  }
 
  mPoints[geometryIndex][ringIndex].last() = p;
 
  updateRect();
  update();
}
 
void QgsRubberBand::movePoint( int index, const QgsPointXY &p, int geometryIndex, int ringIndex )
{
  if ( geometryIndex < 0 || ringIndex < 0 || index < 0 || mPoints.size() <= geometryIndex || mPoints.at( geometryIndex ).size() <= ringIndex || mPoints.at( geometryIndex ).at( ringIndex ).size() <= index )
  {
    return;
  }
 
  mPoints[geometryIndex][ringIndex][index] = p;
 
  updateRect();
  update();
}
 
void QgsRubberBand::setToGeometry( const QgsGeometry &geom, QgsVectorLayer *layer )
{
  if ( geom.isNull() )
  {
    reset( mGeometryType );
    return;
  }
 
  reset( geom.type() );
  addGeometry( geom, layer );
}
 
void QgsRubberBand::setToGeometry( const QgsGeometry &geom, const QgsCoordinateReferenceSystem &crs )
{
  if ( geom.isNull() )
  {
    reset( mGeometryType );
    return;
  }
 
  reset( geom.type() );
  addGeometry( geom, crs );
}
 
void QgsRubberBand::addGeometry( const QgsGeometry &geometry, QgsMapLayer *layer, bool doUpdate )
{
  QgsGeometry geom = geometry;
  if ( layer )
  {
    QgsCoordinateTransform ct = mMapCanvas->mapSettings().layerTransform( layer );
    try
    {
      geom.transform( ct );
    }
    catch ( QgsCsException & )
    {
      return;
    }
  }
 
  addGeometry( geom, QgsCoordinateReferenceSystem(), doUpdate );
}
 
void QgsRubberBand::addGeometry( const QgsGeometry &geometry, const QgsCoordinateReferenceSystem &crs, bool doUpdate )
{
  if ( geometry.isEmpty() )
  {
    return;
  }
 
  //maprender object of canvas
  const QgsMapSettings &ms = mMapCanvas->mapSettings();
 
  int idx = mPoints.size();
 
  QgsGeometry geom = geometry;
  if ( crs.isValid() )
  {
    QgsCoordinateTransform ct( crs, ms.destinationCrs(), QgsProject::instance() );
    try
    {
      geom.transform( ct );
    }
    catch ( QgsCsException & )
    {
      QgsDebugError( u"Could not transform rubber band geometry to map CRS"_s );
      return;
    }
  }
 
  Qgis::WkbType geomType = geom.wkbType();
  if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Point && !QgsWkbTypes::isMultiType( geomType ) )
  {
    QgsPointXY pt = geom.asPoint();
    addPoint( pt, false, idx );
  }
  else if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Point && QgsWkbTypes::isMultiType( geomType ) )
  {
    const QgsMultiPointXY mpt = geom.asMultiPoint();
    for ( const QgsPointXY &pt : mpt )
    {
      addPoint( pt, false, idx );
      idx++;
    }
  }
  else if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Line && !QgsWkbTypes::isMultiType( geomType ) )
  {
    const QgsPolylineXY line = geom.asPolyline();
    for ( const QgsPointXY &pt : line )
    {
      addPoint( pt, false, idx );
    }
  }
  else if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Line && QgsWkbTypes::isMultiType( geomType ) )
  {
    const QgsMultiPolylineXY mline = geom.asMultiPolyline();
    for ( const QgsPolylineXY &line : mline )
    {
      if ( line.isEmpty() )
      {
        continue;
      }
      for ( const QgsPointXY &pt : line )
      {
        addPoint( pt, false, idx );
      }
      idx++;
    }
  }
  else if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Polygon && !QgsWkbTypes::isMultiType( geomType ) )
  {
    const QgsPolygonXY poly = geom.asPolygon();
    int ringIdx = 0;
    for ( const QgsPolylineXY &ring : poly )
    {
      for ( const QgsPointXY &pt : ring )
      {
        addPoint( pt, false, idx, ringIdx );
      }
      ringIdx++;
    }
  }
  else if ( QgsWkbTypes::geometryType( geomType ) == Qgis::GeometryType::Polygon && QgsWkbTypes::isMultiType( geomType ) )
  {
    const QgsMultiPolygonXY multipoly = geom.asMultiPolygon();
    for ( const QgsPolygonXY &poly : multipoly )
    {
      if ( poly.isEmpty() )
        continue;
 
      int ringIdx = 0;
      for ( const QgsPolylineXY &ring : poly )
      {
        for ( const QgsPointXY &pt : ring )
        {
          addPoint( pt, false, idx, ringIdx );
        }
        ringIdx++;
      }
      idx++;
    }
  }
  else
  {
    return;
  }
 
  setVisible( true );
  if ( doUpdate )
  {
    updateRect();
    update();
  }
}
 
void QgsRubberBand::setToCanvasRectangle( QRect rect )
{
  if ( !mMapCanvas )
  {
    return;
  }
 
  const QgsMapToPixel *transform = mMapCanvas->getCoordinateTransform();
  QgsPointXY ll = transform->toMapCoordinates( rect.left(), rect.bottom() );
  QgsPointXY lr = transform->toMapCoordinates( rect.right(), rect.bottom() );
  QgsPointXY ul = transform->toMapCoordinates( rect.left(), rect.top() );
  QgsPointXY ur = transform->toMapCoordinates( rect.right(), rect.top() );
 
  reset( Qgis::GeometryType::Polygon );
  addPoint( ll, false );
  addPoint( lr, false );
  addPoint( ur, false );
  addPoint( ul, true );
}
 
void QgsRubberBand::copyPointsFrom( const QgsRubberBand *other )
{
  reset( other->mGeometryType );
  mPoints = other->mPoints;
  updateRect();
  update();
}
 
void QgsRubberBand::paint( QPainter *p )
{
  if ( mPoints.isEmpty() )
    return;
 
  QgsRenderContext context;
  if ( mMapCanvas )
  {
    context = QgsRenderContext::fromMapSettings( mMapCanvas->mapSettings() );
    if ( QPaintDevice *device = p->device() )
    {
      context.setScaleFactor( device->physicalDpiX() / 25.4 );
    }
    context.setPainter( p );
  }
  else
  {
    context = QgsRenderContext::fromQPainter( p );
    context.setFlag( Qgis::RenderContextFlag::Antialiasing, true );
  }
 
  QVector<QVector<QPolygonF>> shapes;
  shapes.reserve( mPoints.size() );
  for ( const QgsPolygonXY &poly : std::as_const( mPoints ) )
  {
    QVector<QPolygonF> rings;
    rings.reserve( poly.size() );
    for ( const QgsPolylineXY &line : poly )
    {
      QVector<QPointF> pts;
      pts.reserve( line.size() );
      for ( const QgsPointXY &pt : line )
      {
        const QPointF cur = toCanvasCoordinates( QgsPointXY( pt.x() + mTranslationOffsetX, pt.y() + mTranslationOffsetY ) ) - pos();
        if ( pts.isEmpty() || std::abs( pts.last().x() - cur.x() ) > 1 || std::abs( pts.last().y() - cur.y() ) > 1 )
          pts.append( cur );
      }
      rings.append( pts );
    }
    shapes.append( rings );
  }
 
  if ( mComponentsToRender.testFlag( Qgis::RubberBandComponent::Symbol ) )
  {
    if ( QgsLineSymbol *lineSymbol = dynamic_cast<QgsLineSymbol *>( mSymbol.get() ) )
    {
      lineSymbol->startRender( context );
      for ( const QVector<QPolygonF> &shape : std::as_const( shapes ) )
      {
        for ( const QPolygonF &ring : shape )
        {
          lineSymbol->renderPolyline( ring, nullptr, context );
        }
      }
      lineSymbol->stopRender( context );
    }
    else if ( QgsFillSymbol *fillSymbol = dynamic_cast<QgsFillSymbol *>( mSymbol.get() ) )
    {
      fillSymbol->startRender( context );
      for ( const QVector<QPolygonF> &shape : std::as_const( shapes ) )
      {
        for ( const QPolygonF &ring : shape )
        {
          fillSymbol->renderPolygon( ring, nullptr, nullptr, context );
        }
      }
      fillSymbol->stopRender( context );
    }
    else
    {
      int iterations = mSecondaryPen.color().isValid() ? 2 : 1;
      for ( int i = 0; i < iterations; ++i )
      {
        if ( i == 0 && iterations > 1 )
        {
          // first iteration with multi-pen painting, so use secondary pen
          mSecondaryPen.setWidthF( mPen.widthF() + QgsGuiUtils::scaleIconSize( 2 ) );
          p->setBrush( Qt::NoBrush );
          p->setPen( mSecondaryPen );
        }
        else
        {
          // "top" layer, use primary pen/brush
          p->setBrush( mBrush );
          p->setPen( mPen );
        }
 
        for ( const QVector<QPolygonF> &shape : std::as_const( shapes ) )
        {
          drawShape( p, shape );
        }
      }
    }
  }
 
  if ( mComponentsToRender.testFlag( Qgis::RubberBandComponent::PreviewItems ) )
  {
    for ( const auto &item : mPreviewItems )
    {
      if ( item )
      {
        item->render( context );
      }
    }
  }
}
 
void QgsRubberBand::drawShape( QPainter *p, const QVector<QPolygonF> &rings )
{
  if ( rings.size() == 1 )
  {
    drawShape( p, rings.at( 0 ) );
  }
  else
  {
    QPainterPath path;
    for ( const QPolygonF &poly : rings )
    {
      path.addPolygon( poly );
    }
    p->drawPath( path );
  }
}
 
void QgsRubberBand::drawShape( QPainter *p, const QVector<QPointF> &pts )
{
  switch ( mGeometryType )
  {
    case Qgis::GeometryType::Polygon:
    {
      p->drawPolygon( pts );
    }
    break;
 
    case Qgis::GeometryType::Point:
    {
      const auto constPts = pts;
      for ( QPointF pt : constPts )
      {
        double x = pt.x();
        double y = pt.y();
 
        qreal s = ( mIconSize - 1 ) / 2.0;
 
        switch ( mIconType )
        {
          case Qgis::RubberBandIconType::NoIcon:
            break;
 
          case Qgis::RubberBandIconType::CrossPlus:
            p->drawLine( QLineF( x - s, y, x + s, y ) );
            p->drawLine( QLineF( x, y - s, x, y + s ) );
            break;
 
          case Qgis::RubberBandIconType::CrossX:
            p->drawLine( QLineF( x - s, y - s, x + s, y + s ) );
            p->drawLine( QLineF( x - s, y + s, x + s, y - s ) );
            break;
 
          case Qgis::RubberBandIconType::Box:
            p->drawLine( QLineF( x - s, y - s, x + s, y - s ) );
            p->drawLine( QLineF( x + s, y - s, x + s, y + s ) );
            p->drawLine( QLineF( x + s, y + s, x - s, y + s ) );
            p->drawLine( QLineF( x - s, y + s, x - s, y - s ) );
            break;
 
          case Qgis::RubberBandIconType::BoxFilled:
            p->drawRect( QRectF( static_cast<int>( x - s ), static_cast<int>( y - s ), mIconSize, mIconSize ) );
            break;
 
          case Qgis::RubberBandIconType::Circle:
            p->drawEllipse( QRectF( static_cast<int>( x - s ), static_cast<int>( y - s ), mIconSize, mIconSize ) );
            break;
 
          case Qgis::RubberBandIconType::Diamond:
          case Qgis::RubberBandIconType::DiamondFilled:
          {
            QPointF pts[] = { QPointF( x, y - s ), QPointF( x + s, y ), QPointF( x, y + s ), QPointF( x - s, y ) };
            if ( mIconType == Qgis::RubberBandIconType::DiamondFilled )
              p->drawPolygon( pts, 4 );
            else
              p->drawPolyline( pts, 4 );
            break;
          }
 
          case Qgis::RubberBandIconType::SVG:
          {
            QRectF viewBox = mSvgRenderer->viewBoxF();
            QRectF r( mSvgOffset.x(), mSvgOffset.y(), viewBox.width(), viewBox.height() );
            QgsScopedQPainterState painterState( p );
            p->translate( pt );
            mSvgRenderer->render( p, r );
            break;
          }
        }
      }
    }
    break;
 
    case Qgis::GeometryType::Line:
    default:
    {
      p->drawPolyline( pts );
    }
    break;
  }
}
 
void QgsRubberBand::updateRect()
{
  if ( mPoints.isEmpty() )
  {
    setRect( QgsRectangle() );
    setVisible( false );
    return;
  }
 
  const QgsMapToPixel &m2p = *( mMapCanvas->getCoordinateTransform() );
 
#if 0 // unused?
  double iconSize = ( mIconSize + 1 ) / 2.;
  if ( mSvgRenderer )
  {
    QRectF viewBox = mSvgRenderer->viewBoxF();
    iconSize = std::max( std::fabs( mSvgOffset.x() ) + .5 * viewBox.width(), std::fabs( mSvgOffset.y() ) + .5 * viewBox.height() );
  }
#endif
 
  qreal w = ( ( mIconSize - 1 ) / 2 + mPen.widthF() ); // in canvas units
 
  QgsRectangle r; // in canvas units
  for ( const QgsPolygonXY &poly : std::as_const( mPoints ) )
  {
    for ( const QgsPointXY &point : poly.at( 0 ) )
    {
      QgsPointXY p( point.x() + mTranslationOffsetX, point.y() + mTranslationOffsetY );
      p = m2p.transform( p );
      // no need to normalize the rectangle -- we know it is already normal
      QgsRectangle rect( p.x() - w, p.y() - w, p.x() + w, p.y() + w, false );
      r.combineExtentWith( rect );
    }
  }
 
  // This is an hack to pass QgsMapCanvasItem::setRect what it
  // expects (encoding of position and size of the item)
  qreal res = m2p.mapUnitsPerPixel();
  QgsPointXY topLeft = m2p.toMapCoordinates( r.xMinimum(), r.yMinimum() );
  QgsRectangle rect( topLeft.x(), topLeft.y(), topLeft.x() + r.width() * res, topLeft.y() - r.height() * res );
 
  setRect( rect );
}
 
Qgis::RubberBandComponents QgsRubberBand::renderedComponents() const
{
  return mComponentsToRender;
}
 
void QgsRubberBand::setRenderedComponents( Qgis::RubberBandComponents components )
{
  mComponentsToRender = components;
}
 
QRectF QgsRubberBand::boundingRect() const
{
  QRectF res = QgsMapCanvasItem::boundingRect();
 
  if ( mComponentsToRender.testFlag( Qgis::RubberBandComponent::PreviewItems ) )
  {
    for ( const std::unique_ptr<QgsRubberBandPreviewItem> &previewItem : mPreviewItems )
    {
      const QRectF itemBounds = previewItem->boundingRect();
      if ( itemBounds.isValid() )
      {
        res = res.united( itemBounds );
      }
    }
  }
  return res;
}
 
QgsSymbol *QgsRubberBand::symbol() const
{
  return mSymbol.get();
}
 
void QgsRubberBand::setSymbol( QgsSymbol *symbol )
{
  mSymbol.reset( symbol );
}
 
void QgsRubberBand::updatePosition()
{
  // re-compute rectangle
  // See https://github.com/qgis/QGIS/issues/20566
  // NOTE: could be optimized by saving map-extent
  //       of rubberband and simply re-projecting
  //       that to device-rectangle on "updatePosition"
  updateRect();
}
 
void QgsRubberBand::setTranslationOffset( double dx, double dy )
{
  mTranslationOffsetX = dx;
  mTranslationOffsetY = dy;
  updateRect();
}
 
int QgsRubberBand::size() const
{
  return mPoints.size();
}
 
int QgsRubberBand::partSize( int geometryIndex ) const
{
  if ( geometryIndex < 0 || geometryIndex >= mPoints.size() || mPoints.at( geometryIndex ).isEmpty() )
    return 0;
  return mPoints.at( geometryIndex ).at( 0 ).size();
}
 
int QgsRubberBand::numberOfVertices() const
{
  int count = 0;
  for ( const QgsPolygonXY &poly : std::as_const( mPoints ) )
  {
    for ( const QgsPolylineXY &ring : poly )
    {
      count += ring.size();
    }
  }
  return count;
}
 
const QgsPointXY *QgsRubberBand::getPoint( int i, int j, int ringIndex ) const
{
  if ( i < 0 || ringIndex < 0 || j < 0 || mPoints.size() <= i || mPoints.at( i ).size() <= ringIndex || mPoints.at( i ).at( ringIndex ).size() <= j )
    return nullptr;
  else
    return &mPoints[i][ringIndex][j];
}
 
QgsGeometry QgsRubberBand::asGeometry() const
{
  QgsGeometry geom;
 
  switch ( mGeometryType )
  {
    case Qgis::GeometryType::Polygon:
    {
      geom = QgsGeometry::fromMultiPolygonXY( mPoints );
      break;
    }
 
    case Qgis::GeometryType::Point:
    {
      QgsMultiPointXY multiPoint;
 
      for ( const QgsPolygonXY &poly : std::as_const( mPoints ) )
      {
        if ( poly.isEmpty() )
          continue;
        multiPoint.append( poly.at( 0 ) );
      }
      geom = QgsGeometry::fromMultiPointXY( multiPoint );
      break;
    }
 
    case Qgis::GeometryType::Line:
    default:
    {
      if ( !mPoints.isEmpty() )
      {
        if ( mPoints.size() > 1 )
        {
          QgsMultiPolylineXY multiPolyline;
          for ( const QgsPolygonXY &poly : std::as_const( mPoints ) )
          {
            if ( poly.isEmpty() )
              continue;
            multiPolyline.append( poly.at( 0 ) );
          }
          geom = QgsGeometry::fromMultiPolylineXY( multiPolyline );
        }
        else
        {
          if ( !mPoints.at( 0 ).isEmpty() )
            geom = QgsGeometry::fromPolylineXY( mPoints.at( 0 ).at( 0 ) );
          else
            geom = QgsGeometry::fromPolylineXY( QgsPolylineXY() );
        }
      }
      break;
    }
  }
  return geom;
}
 
//
// QgsRubberBandPreviewItem
//
 
QgsRubberBandPreviewItem::QgsRubberBandPreviewItem( QgsRubberBand *rubberBand )
  : mRubberBand( rubberBand )
{}
 
QgsRubberBand *QgsRubberBandPreviewItem::rubberBand()
{
  return mRubberBand.data();
}
 
QRectF QgsRubberBandPreviewItem::boundingRect() const
{
  return QRectF();
}