qgsannotationlineitem.cpp

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/***************************************************************************
    qgsannotationlineitem.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 "qgsannotationlineitem.h"
#include "qgssymbol.h"
#include "qgssymbollayerutils.h"
#include "qgslinesymbol.h"
 
QgsAnnotationLineItem::QgsAnnotationLineItem( QgsCurve *curve )
  : QgsAnnotationItem()
  , mCurve( curve )
  , mSymbol( std::make_unique< QgsLineSymbol >() )
{
 
}
 
QgsAnnotationLineItem::~QgsAnnotationLineItem() = default;
 
QString QgsAnnotationLineItem::type() const
{
  return QStringLiteral( "linestring" );
}
 
void QgsAnnotationLineItem::render( QgsRenderContext &context, QgsFeedback * )
{
  QPolygonF pts = mCurve->asQPolygonF();
 
  //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() );
  }
 
  mSymbol->startRender( context );
  mSymbol->renderPolyline( pts, nullptr, context );
  mSymbol->stopRender( context );
}
 
bool QgsAnnotationLineItem::writeXml( QDomElement &element, QDomDocument &document, const QgsReadWriteContext &context ) const
{
  element.setAttribute( QStringLiteral( "wkt" ), mCurve->asWkt() );
  element.setAttribute( QStringLiteral( "zIndex" ), zIndex() );
 
  element.appendChild( QgsSymbolLayerUtils::saveSymbol( QStringLiteral( "lineSymbol" ), mSymbol.get(), document, context ) );
 
  return true;
}
 
QgsAnnotationLineItem *QgsAnnotationLineItem::create()
{
  return new QgsAnnotationLineItem( new QgsLineString() );
}
 
bool QgsAnnotationLineItem::readXml( const QDomElement &element, const QgsReadWriteContext &context )
{
  const QString wkt = element.attribute( QStringLiteral( "wkt" ) );
  const QgsGeometry geometry = QgsGeometry::fromWkt( wkt );
  if ( const QgsCurve *curve = qgsgeometry_cast< const QgsCurve * >( geometry.constGet() ) )
    mCurve.reset( curve->clone() );
 
  setZIndex( element.attribute( QStringLiteral( "zIndex" ) ).toInt() );
 
  const QDomElement symbolElem = element.firstChildElement( QStringLiteral( "symbol" ) );
  if ( !symbolElem.isNull() )
    setSymbol( QgsSymbolLayerUtils::loadSymbol< QgsLineSymbol >( symbolElem, context ) );
 
  return true;
}
 
QgsRectangle QgsAnnotationLineItem::boundingBox() const
{
  return mCurve->boundingBox();
}
 
QgsAnnotationLineItem *QgsAnnotationLineItem::clone()
{
  std::unique_ptr< QgsAnnotationLineItem > item = std::make_unique< QgsAnnotationLineItem >( mCurve->clone() );
  item->setSymbol( mSymbol->clone() );
  item->setZIndex( zIndex() );
  return item.release();
}
 
const QgsLineSymbol *QgsAnnotationLineItem::symbol() const
{
  return mSymbol.get();
}
 
void QgsAnnotationLineItem::setSymbol( QgsLineSymbol *symbol )
{
  mSymbol.reset( symbol );
}