qgslabelsink.h

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/***************************************************************************
                         qgslabelsink.h
                         -------------------
    begin                : January 2014
    copyright            : (C) 2014 by Marco Hugentobler
    email                : marco at sourcepole dot ch
 ***************************************************************************/
 
/***************************************************************************
 *                                                                         *
 *   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 QGSLABELSINK_H
#define QGSLABELSINK_H
 
 
#include "qgsrulebasedlabeling.h"
#include "qgsvectorlayerlabelprovider.h"
 
#define SIP_NO_FILE
 
class QgsPalLayerSettings;
class QgsRuleBasedLabeling;

class QgsLabelSink
{
  public:
    virtual ~QgsLabelSink() = default;

    virtual void drawLabel( const QString &layerId, QgsRenderContext &context, pal::LabelPosition *label, const QgsPalLayerSettings &settings ) = 0;

    virtual void drawUnplacedLabel( const QString &layerId, QgsRenderContext &context, pal::LabelPosition *label, const QgsPalLayerSettings &settings )
    {
      Q_UNUSED( layerId );
      Q_UNUSED( context )
      Q_UNUSED( label );
      Q_UNUSED( settings );
      return;
    }
};

class QgsLabelSinkProvider : public QgsVectorLayerLabelProvider
{
  public:
    explicit QgsLabelSinkProvider( QgsVectorLayer *layer, const QString &providerId, QgsLabelSink *sink, const QgsPalLayerSettings *settings );
 
    void drawLabel( QgsRenderContext &context, pal::LabelPosition *label ) const override;
    void drawUnplacedLabel( QgsRenderContext &context, pal::LabelPosition *label ) const override;
 
  private:
    QgsLabelSink *mLabelSink = nullptr;
};

class QgsRuleBasedLabelSinkProvider : public QgsRuleBasedLabelProvider
{
  public:
    explicit QgsRuleBasedLabelSinkProvider( const QgsRuleBasedLabeling &rules, QgsVectorLayer *layer, QgsLabelSink *sink );

    Q_DECL_DEPRECATED void reinit( QgsVectorLayer *layer );
 
    void drawLabel( QgsRenderContext &context, pal::LabelPosition *label ) const override;
    void drawUnplacedLabel( QgsRenderContext &context, pal::LabelPosition *label ) const override;

    QgsVectorLayerLabelProvider *createProvider( QgsVectorLayer *layer, const QString &providerId, bool withFeatureLoop, const QgsPalLayerSettings *settings ) override;
 
  private:
    QgsLabelSink *mLabelSink = nullptr;
};
 
 
 
#endif // QGSLABELSINK_H