QGIS/src/app/qgsmaptoolrotatepointsymbols.h

/***************************************************************************
    qgsmaptoolrotatepointsymbols.h
    ---------------------
    begin                : September 2009
    copyright            : (C) 2009 by Marco Hugentobler
    email                : marco at hugis dot net
 ***************************************************************************
 *                                                                         *
 *   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 QGSMAPTOOLROTATEPOINTSYMBOLS_H
#define QGSMAPTOOLROTATEPOINTSYMBOLS_H

#include "qgsmaptoolpointsymbol.h"
#include "qgis_app.h"
#include <memory>

class QgsPointRotationItem;
class QgsMarkerSymbol;

/**
 * \ingroup app
 * \class QgsMapToolRotatePointSymbols
 * \brief A class that allows interactive manipulation the value of the rotation field(s) for point layers.
 */

class APP_EXPORT QgsMapToolRotatePointSymbols: public QgsMapToolPointSymbol
{
    Q_OBJECT

  public:
    QgsMapToolRotatePointSymbols( QgsMapCanvas *canvas );
    ~QgsMapToolRotatePointSymbols() override;

    void canvasPressEvent( QgsMapMouseEvent *e ) override;
    void canvasMoveEvent( QgsMapMouseEvent *e ) override;
    void canvasReleaseEvent( QgsMapMouseEvent *e ) override;

    /**
     * Returns true if the symbols of a maplayer can be rotated. This means the layer
      is a vector layer, has type point or multipoint and has at least one rotation attribute in the renderer*/
    static bool layerIsRotatable( QgsMapLayer *ml );

  protected:

    void canvasPressOnFeature( QgsMapMouseEvent *e, const QgsFeature &feature, const QgsPointXY &snappedPoint ) override;
    bool checkSymbolCompatibility( QgsMarkerSymbol *markerSymbol, QgsRenderContext &context ) override;
    void noCompatibleSymbols() override;

  private:

    //! Last azimut between mouse and edited point
    double mCurrentMouseAzimut;
    //! Last feature rotation
    double mCurrentRotationFeature;
    bool mRotating;
    QSet<int> mCurrentRotationAttributes;
    //! Item that displays rotation during mouse move
    QgsPointRotationItem *mRotationItem = nullptr;
    //! True if ctrl was pressed during the last mouse move event
    bool mCtrlPressed;
    //! Clone of first found marker symbol for feature with rotation attribute set
    std::unique_ptr< QgsMarkerSymbol > mMarkerSymbol;

    void drawArrow( double azimut ) const;
    //! Calculates the azimut between mousePos and mSnappedPoint
    double calculateAzimut( QPoint mousePos );
    //! Create item with the point symbol for a specific feature. This will be used to show the rotation to the user
    void createPixmapItem( QgsMarkerSymbol *markerSymbol );
    //! Sets the rotation of the pixmap item
    void setPixmapItemRotation( double rotation );
    //! Rounds value to 15 degree integer (used if ctrl pressed)
    static int roundTo15Degrees( double n );

};

#endif // QGSMAPTOOLROTATEPOINTSYMBOLS_H