qgsvectorlayerdiagramprovider.h

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/***************************************************************************
  qgsvectorlayerdiagramprovider.h
  --------------------------------------
  Date                 : September 2015
  Copyright            : (C) 2015 by Martin Dobias
  Email                : wonder dot sk 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.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSVECTORLAYERDIAGRAMPROVIDER_H
#define QGSVECTORLAYERDIAGRAMPROVIDER_H

#define SIP_NO_FILE

#include "qgis_core.h"
#include "qgslabelingengine.h"
#include "qgslabelfeature.h"
#include "qgsdiagramrenderer.h"

class QgsDiagramLabelFeature : public QgsLabelFeature
{
  public:
    QgsDiagramLabelFeature( QgsFeatureId id, geos::unique_ptr geometry, QSizeF size )
      : QgsLabelFeature( id, std::move( geometry ), size ) {}

    void setAttributes( const QgsAttributes &attrs ) { mAttributes = attrs; }
    const QgsAttributes &attributes() { return mAttributes; }

  protected:
    QgsAttributes mAttributes;
};


class QgsAbstractFeatureSource;

class CORE_EXPORT QgsVectorLayerDiagramProvider : public QgsAbstractLabelProvider
{
  public:

    explicit QgsVectorLayerDiagramProvider( QgsVectorLayer *layer, bool ownFeatureLoop = true );

    ~QgsVectorLayerDiagramProvider() override;

    QList<QgsLabelFeature *> labelFeatures( QgsRenderContext &context ) override;

    void drawLabel( QgsRenderContext &context, pal::LabelPosition *label ) const override;

    // new virtual methods

    virtual bool prepare( const QgsRenderContext &context, QSet<QString> &attributeNames );

    virtual void registerFeature( QgsFeature &feature, QgsRenderContext &context, const QgsGeometry &obstacleGeometry = QgsGeometry() );

  protected:
    void init();
    QgsLabelFeature *registerDiagram( QgsFeature &feat, QgsRenderContext &context, const QgsGeometry &obstacleGeometry = QgsGeometry() );

  protected:

    QgsDiagramLayerSettings mSettings;
    QgsDiagramRenderer *mDiagRenderer = nullptr;

    // these are needed only if using own renderer loop

    QgsFields mFields;
    QgsCoordinateReferenceSystem mLayerCrs;
    QgsAbstractFeatureSource *mSource = nullptr;
    bool mOwnsSource;

    QList<QgsLabelFeature *> mFeatures;
};

#endif // QGSVECTORLAYERDIAGRAMPROVIDER_H