qgsmaptoolidentify.h

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/***************************************************************************
    qgsmaptoolidentify.h  -  map tool for identifying features
    ---------------------
    begin                : January 2006
    copyright            : (C) 2006 by Martin Dobias
    email                : wonder.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 QGSMAPTOOLIDENTIFY_H
#define QGSMAPTOOLIDENTIFY_H

#include "qgsfeature.h"
#include "qgsfields.h"
#include "qgsmaptool.h"
#include "qgspointxy.h"
#include "qgsunittypes.h"

#include <QObject>
#include <QPointer>
#include "qgis_gui.h"

class QgsRasterLayer;
class QgsVectorLayer;
class QgsMapLayer;
class QgsMapCanvas;
class QgsHighlight;
class QgsIdentifyMenu;
class QgsDistanceArea;

class GUI_EXPORT QgsMapToolIdentify : public QgsMapTool
{
    Q_OBJECT

  public:

    enum IdentifyMode
    {
      DefaultQgsSetting = -1,
      ActiveLayer,
      TopDownStopAtFirst,
      TopDownAll,
      LayerSelection
    };
    Q_ENUM( IdentifyMode )

    enum Type
    {
      VectorLayer = 1,
      RasterLayer = 2,
      AllLayers = VectorLayer | RasterLayer
    };
    Q_DECLARE_FLAGS( LayerType, Type )
    Q_FLAG( LayerType )

    struct IdentifyResult
    {
      IdentifyResult() = default;

      IdentifyResult( QgsMapLayer *layer, const QgsFeature &feature, const QMap< QString, QString > &derivedAttributes )
        : mLayer( layer ), mFeature( feature ), mDerivedAttributes( derivedAttributes ) {}

      IdentifyResult( QgsMapLayer *layer, const QString &label, const QMap< QString, QString > &attributes, const QMap< QString, QString > &derivedAttributes )
        : mLayer( layer ), mLabel( label ), mAttributes( attributes ), mDerivedAttributes( derivedAttributes ) {}

      IdentifyResult( QgsMapLayer *layer, const QString &label, const QgsFields &fields, const QgsFeature &feature, const QMap< QString, QString > &derivedAttributes )
        : mLayer( layer ), mLabel( label ), mFields( fields ), mFeature( feature ), mDerivedAttributes( derivedAttributes ) {}

      QgsMapLayer *mLayer = nullptr;
      QString mLabel;
      QgsFields mFields;
      QgsFeature mFeature;
      QMap< QString, QString > mAttributes;
      QMap< QString, QString > mDerivedAttributes;
      QMap< QString, QVariant > mParams;
    };

    QgsMapToolIdentify( QgsMapCanvas *canvas );

    ~QgsMapToolIdentify() override;

    Flags flags() const override { return QgsMapTool::AllowZoomRect; }
    void canvasMoveEvent( QgsMapMouseEvent *e ) override;
    void canvasPressEvent( QgsMapMouseEvent *e ) override;
    void canvasReleaseEvent( QgsMapMouseEvent *e ) override;
    void activate() override;
    void deactivate() override;

    QList<QgsMapToolIdentify::IdentifyResult> identify( int x, int y, const QList<QgsMapLayer *> &layerList = QList<QgsMapLayer *>(), IdentifyMode mode = DefaultQgsSetting );

    QList<QgsMapToolIdentify::IdentifyResult> identify( int x, int y, IdentifyMode mode, LayerType layerType = AllLayers );

    QgsIdentifyMenu *identifyMenu() {return mIdentifyMenu;}

  public slots:
    void formatChanged( QgsRasterLayer *layer );

  signals:
    void identifyProgress( int, int );
    void identifyMessage( const QString & );
    void changedRasterResults( QList<QgsMapToolIdentify::IdentifyResult> & );

  protected:

    QList<QgsMapToolIdentify::IdentifyResult> identify( int x, int y, IdentifyMode mode,  const QList<QgsMapLayer *> &layerList, LayerType layerType = AllLayers );

    QgsIdentifyMenu *mIdentifyMenu = nullptr;

    bool identifyLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsMapLayer *layer, const QgsPointXY &point, const QgsRectangle &viewExtent, double mapUnitsPerPixel, QgsMapToolIdentify::LayerType layerType = AllLayers );

    bool identifyRasterLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsRasterLayer *layer, QgsPointXY point, const QgsRectangle &viewExtent, double mapUnitsPerPixel );
    bool identifyVectorLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsVectorLayer *layer, const QgsPointXY &point );

  private:

    virtual QgsUnitTypes::DistanceUnit displayDistanceUnits() const;

    virtual QgsUnitTypes::AreaUnit displayAreaUnits() const;

    QString formatDistance( double distance ) const;

    QString formatArea( double area ) const;

    QMap< QString, QString > featureDerivedAttributes( QgsFeature *feature, QgsMapLayer *layer, const QgsPointXY &layerPoint = QgsPointXY() );

    void closestVertexAttributes( const QgsAbstractGeometry &geometry, QgsVertexId vId, QgsMapLayer *layer, QMap< QString, QString > &derivedAttributes );

    QString formatCoordinate( const QgsPointXY &canvasPoint ) const;
    QString formatXCoordinate( const QgsPointXY &canvasPoint ) const;
    QString formatYCoordinate( const QgsPointXY &canvasPoint ) const;

    // Last point in canvas CRS
    QgsPointXY mLastPoint;

    double mLastMapUnitsPerPixel;

    QgsRectangle mLastExtent;

    int mCoordinatePrecision;
};

Q_DECLARE_OPERATORS_FOR_FLAGS( QgsMapToolIdentify::LayerType )

#endif