qgsannotationpolygonitem.cpp

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/***************************************************************************
    qgsannotationpolygonitem.cpp
    ----------------
    begin                : July 2020
    copyright            : (C) 2020 by Nyall Dawson
    email                : nyall dot dawson at gmail dot com
 ***************************************************************************/
 
/***************************************************************************
 *                                                                         *
 *   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 "qgsannotationpolygonitem.h"
#include "qgssymbol.h"
#include "qgssymbollayerutils.h"
#include "qgssurface.h"
#include "qgsfillsymbol.h"
 
QgsAnnotationPolygonItem::QgsAnnotationPolygonItem( QgsCurvePolygon *polygon )
  : QgsAnnotationItem()
  , mPolygon( polygon )
  , mSymbol( std::make_unique< QgsFillSymbol >() )
{
 
}
 
QgsAnnotationPolygonItem::~QgsAnnotationPolygonItem() = default;
 
QString QgsAnnotationPolygonItem::type() const
{
  return QStringLiteral( "polygon" );
}
 
void QgsAnnotationPolygonItem::render( QgsRenderContext &context, QgsFeedback * )
{
 
  auto transformRing = [&context]( QPolygonF & pts )
  {
    //transform the QPolygonF to screen coordinates
    if ( context.coordinateTransform().isValid() )
    {
      try
      {
        context.coordinateTransform().transformPolygon( pts );
      }
      catch ( QgsCsException & )
      {
        // we don't abort the rendering here, instead we remove any invalid points and just plot those which ARE valid
      }
    }
 
    // remove non-finite points, e.g. infinite or NaN points caused by reprojecting errors
    pts.erase( std::remove_if( pts.begin(), pts.end(),
                               []( const QPointF point )
    {
      return !std::isfinite( point.x() ) || !std::isfinite( point.y() );
    } ), pts.end() );
 
    QPointF *ptr = pts.data();
    for ( int i = 0; i < pts.size(); ++i, ++ptr )
    {
      context.mapToPixel().transformInPlace( ptr->rx(), ptr->ry() );
    }
  };
 
  QPolygonF exterior = mPolygon->exteriorRing()->asQPolygonF();
  transformRing( exterior );
  QVector<QPolygonF> rings;
  rings.reserve( mPolygon->numInteriorRings() );
  for ( int i = 0; i < mPolygon->numInteriorRings(); ++i )
  {
    QPolygonF ring = mPolygon->interiorRing( i )->asQPolygonF();
    transformRing( ring );
    rings.append( ring );
  }
 
  mSymbol->startRender( context );
  mSymbol->renderPolygon( exterior, rings.empty() ? nullptr : &rings, nullptr, context );
  mSymbol->stopRender( context );
}
 
bool QgsAnnotationPolygonItem::writeXml( QDomElement &element, QDomDocument &document, const QgsReadWriteContext &context ) const
{
  element.setAttribute( QStringLiteral( "wkt" ), mPolygon->asWkt() );
 
  element.setAttribute( QStringLiteral( "zIndex" ), zIndex() );
  element.appendChild( QgsSymbolLayerUtils::saveSymbol( QStringLiteral( "lineSymbol" ), mSymbol.get(), document, context ) );
 
  return true;
}
 
QgsAnnotationPolygonItem *QgsAnnotationPolygonItem::create()
{
  return new QgsAnnotationPolygonItem( new QgsPolygon() );
}
 
bool QgsAnnotationPolygonItem::readXml( const QDomElement &element, const QgsReadWriteContext &context )
{
  const QString wkt = element.attribute( QStringLiteral( "wkt" ) );
  const QgsGeometry geometry = QgsGeometry::fromWkt( wkt );
  if ( const QgsCurvePolygon *polygon = qgsgeometry_cast< const QgsCurvePolygon * >( geometry.constGet() ) )
    mPolygon.reset( polygon->clone() );
 
  setZIndex( element.attribute( QStringLiteral( "zIndex" ) ).toInt() );
 
  const QDomElement symbolElem = element.firstChildElement( QStringLiteral( "symbol" ) );
  if ( !symbolElem.isNull() )
    setSymbol( QgsSymbolLayerUtils::loadSymbol< QgsFillSymbol >( symbolElem, context ) );
 
  return true;
}
 
QgsAnnotationPolygonItem *QgsAnnotationPolygonItem::clone()
{
  std::unique_ptr< QgsAnnotationPolygonItem > item = std::make_unique< QgsAnnotationPolygonItem >( mPolygon->clone() );
  item->setSymbol( mSymbol->clone() );
  item->setZIndex( zIndex() );
  return item.release();
}
 
QgsRectangle QgsAnnotationPolygonItem::boundingBox() const
{
  return mPolygon->boundingBox();
}
 
const QgsFillSymbol *QgsAnnotationPolygonItem::symbol() const
{
  return mSymbol.get();
}
 
void QgsAnnotationPolygonItem::setSymbol( QgsFillSymbol *symbol )
{
  mSymbol.reset( symbol );
}