qgslabelingenginerule.h

Go to the documentation of this file.

/***************************************************************************
    qgslabelingenginerule.h
    ---------------------
  Date                 : August 2024
  Copyright            : (C) 2024 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.                                   *
 *                                                                         *
 ***************************************************************************/
#ifndef QGSLABELINGENGINERULE_H
#define QGSLABELINGENGINERULE_H
 
#include "qgis.h"
#include "qgis_core.h"
#include "qgis_sip.h"
#include "qgsgeometry.h"
 
class QgsRenderContext;
class QDomDocument;
class QDomElement;
class QgsReadWriteContext;
class QgsProject;
#ifndef SIP_RUN
namespace pal
{
  class LabelPosition;
}
#endif

class CORE_EXPORT QgsLabelingEngineContext
{
  public:
    QgsLabelingEngineContext( QgsRenderContext &renderContext );
 
#ifndef SIP_RUN
    QgsLabelingEngineContext( const QgsLabelingEngineContext &other ) = delete;
    QgsLabelingEngineContext &operator=( const QgsLabelingEngineContext &other ) = delete;
#endif

    QgsRenderContext &renderContext() { return mRenderContext; }

    const QgsRenderContext &renderContext() const SIP_SKIP { return mRenderContext; }

    QgsRectangle extent() const;

    void setExtent( const QgsRectangle &extent );

    QgsGeometry mapBoundaryGeometry() const;

    void setMapBoundaryGeometry( const QgsGeometry &geometry );
 
  private:
#ifdef SIP_RUN
    QgsLabelingEngineContext( const QgsLabelingEngineContext &other );
#endif
 
    QgsRenderContext &mRenderContext;
    QgsRectangle mExtent;
    QgsGeometry mMapBoundaryGeometry;
};

class CORE_EXPORT QgsAbstractLabelingEngineRule
{
#ifdef SIP_RUN
    SIP_CONVERT_TO_SUBCLASS_CODE
    if ( sipCpp->id() == "minimumDistanceLabelToFeature" )
    {
      sipType = sipType_QgsLabelingEngineRuleMinimumDistanceLabelToFeature;
    }
    else if ( sipCpp->id() == "minimumDistanceLabelToLabel" )
    {
      sipType = sipType_QgsLabelingEngineRuleMinimumDistanceLabelToLabel;
    }
    else if ( sipCpp->id() == "maximumDistanceLabelToFeature" )
    {
      sipType = sipType_QgsLabelingEngineRuleMaximumDistanceLabelToFeature;
    }
    else if ( sipCpp->id() == "avoidLabelOverlapWithFeature" )
    {
      sipType = sipType_QgsLabelingEngineRuleAvoidLabelOverlapWithFeature;
    }
    else
    {
      sipType = 0;
    }
  SIP_END
#endif
 
  public:
 
    virtual ~QgsAbstractLabelingEngineRule();

    virtual QgsAbstractLabelingEngineRule *clone() const = 0 SIP_FACTORY;

    virtual QString id() const = 0;

    virtual QString displayType() const = 0;

    virtual bool isAvailable() const;

    virtual QString description() const;

    QString name() const { return mName; }

    void setName( const QString &name ) { mName = name; }

    bool active() const;

    void setActive( bool active );

    virtual bool prepare( QgsRenderContext &context ) = 0;

    virtual void writeXml( QDomDocument &doc, QDomElement &element, const QgsReadWriteContext &context ) const = 0;

    virtual void readXml( const QDomElement &element, const QgsReadWriteContext &context ) = 0;

    virtual void resolveReferences( const QgsProject *project );

    virtual bool candidatesAreConflicting( const pal::LabelPosition *lp1, const pal::LabelPosition *lp2 ) const SIP_SKIP;

    virtual QgsRectangle modifyCandidateConflictSearchBoundingBox( const QgsRectangle &candidateBounds ) const SIP_SKIP;

    virtual bool candidateIsIllegal( const pal::LabelPosition *candidate, QgsLabelingEngineContext &context ) const SIP_SKIP;

    virtual void alterCandidateCost( pal::LabelPosition *candidate, QgsLabelingEngineContext &context ) const SIP_SKIP;
 
  protected:
    virtual void copyCommonProperties( QgsAbstractLabelingEngineRule *other ) const;
 
  private:
    QString mName;
    bool mIsActive = true;
};
 
#endif // QGSLABELINGENGINESETTINGS_H