QGIS API Documentation  3.37.0-Master (a5b4d9743e8)
qgsmaptoolpan.cpp
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1 /***************************************************************************
2  qgsmaptoolpan.h - map tool for panning in map canvas
3  ---------------------
4  begin : January 2006
5  copyright : (C) 2006 by Martin Dobias
6  email : wonder.sk at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #include <QBitmap>
17 #include <QCursor>
18 #include "qgsmaptoolpan.h"
19 #include "qgsmapcanvas.h"
20 #include "qgsmaptopixel.h"
21 #include "qgsmapmouseevent.h"
22 #include "qgsproject.h"
23 
24 
26  : QgsMapTool( canvas )
27  , mDragging( false )
28 {
29  mToolName = tr( "Pan" );
30  // set cursor
31  mCursor = QCursor( Qt::OpenHandCursor );
32 }
33 
35 {
36  if ( mCanvas )
37  mCanvas->ungrabGesture( Qt::PinchGesture );
38 }
39 
41 {
42  mCanvas->grabGesture( Qt::PinchGesture );
44 }
45 
47 {
48  mCanvas->ungrabGesture( Qt::PinchGesture );
50 }
51 
53 {
55 }
56 
58 {
59  if ( e->button() == Qt::LeftButton )
60  {
61  mCanvas->setCursor( QCursor( Qt::ClosedHandCursor ) );
62  mCanvas->panActionStart( e->pos() );
63  }
64 }
65 
66 
68 {
69  if ( !mPinching )
70  {
71  if ( ( e->buttons() & Qt::LeftButton ) )
72  {
73  mDragging = true;
74  // move map and other canvas items
75  mCanvas->panAction( e );
76  }
77  }
78 }
79 
81 {
82  if ( !mPinching )
83  {
84  if ( e->button() == Qt::LeftButton )
85  {
86  if ( mDragging )
87  {
88  mCanvas->panActionEnd( e->pos() );
89  mDragging = false;
90  }
91  else // add pan to mouse cursor
92  {
94  {
95  // transform the mouse pos to map coordinates
96  const QgsPointXY prevCenter = mCanvas->center();
97  const QgsPointXY center = mCanvas->getCoordinateTransform()->toMapCoordinates( e->x(), e->y() );
98  mCanvas->setCenter( center );
99  mCanvas->refresh();
100 
101  QgsDistanceArea da;
102  da.setEllipsoid( QgsProject::instance()->ellipsoid() );
103  da.setSourceCrs( mCanvas->mapSettings().destinationCrs(), QgsProject::instance()->transformContext() );
104  try
105  {
106  emit panDistanceBearingChanged( da.measureLine( center, prevCenter ), da.lengthUnits(), da.bearing( center, prevCenter ) * 180 / M_PI );
107  }
108  catch ( QgsCsException & )
109  {}
110  }
111  }
112  }
113  }
114  mCanvas->setCursor( mCursor );
115 }
116 
118 {
119  if ( !mPinching )
120  {
121  mCanvas->zoomWithCenter( e->x(), e->y(), true );
122  }
123 }
124 
125 bool QgsMapToolPan::gestureEvent( QGestureEvent *event )
126 {
127  if ( QGesture *gesture = event->gesture( Qt::PinchGesture ) )
128  {
129  mPinching = true;
130  pinchTriggered( static_cast<QPinchGesture *>( gesture ) );
131  }
132  return true;
133 }
134 
135 void QgsMapToolPan::pinchTriggered( QPinchGesture *gesture )
136 {
137  if ( gesture->state() == Qt::GestureFinished )
138  {
139  //a very small totalScaleFactor indicates a two finger tap (pinch gesture without pinching)
140  if ( 0.98 < gesture->totalScaleFactor() && gesture->totalScaleFactor() < 1.02 )
141  {
142  mCanvas->zoomOut();
143  }
144  else
145  {
146  //Transfor global coordinates to widget coordinates
147  QPoint pos = gesture->centerPoint().toPoint();
148  pos = mCanvas->mapFromGlobal( pos );
149  // transform the mouse pos to map coordinates
150  const QgsPointXY center = mCanvas->getCoordinateTransform()->toMapCoordinates( pos.x(), pos.y() );
151  QgsRectangle r = mCanvas->extent();
152  r.scale( 1 / gesture->totalScaleFactor(), &center );
153  mCanvas->setExtent( r );
154  mCanvas->refresh();
155  }
156  mPinching = false;
157  }
158 }
Custom exception class for Coordinate Reference System related exceptions.
Definition: qgsexception.h:67
A general purpose distance and area calculator, capable of performing ellipsoid based calculations.
double bearing(const QgsPointXY &p1, const QgsPointXY &p2) const
Computes the bearing (in radians) between two points.
double measureLine(const QVector< QgsPointXY > &points) const
Measures the length of a line with multiple segments.
void setSourceCrs(const QgsCoordinateReferenceSystem &crs, const QgsCoordinateTransformContext &context)
Sets source spatial reference system crs.
Qgis::DistanceUnit lengthUnits() const
Returns the units of distance for length calculations made by this object.
bool setEllipsoid(const QString &ellipsoid)
Sets the ellipsoid by its acronym.
@ MapPanOnSingleClick
A map pan interaction caused by a single click and release on the map canvas.
Map canvas is a class for displaying all GIS data types on a canvas.
Definition: qgsmapcanvas.h:93
A QgsMapMouseEvent is the result of a user interaction with the mouse on a QgsMapCanvas.
~QgsMapToolPan() override
void canvasPressEvent(QgsMapMouseEvent *e) override
Mouse press event for overriding. Default implementation does nothing.
void deactivate() override
called when map tool is being deactivated
QgsMapToolPan(QgsMapCanvas *canvas)
constructor
void canvasDoubleClickEvent(QgsMapMouseEvent *e) override
Mouse double-click event for overriding. Default implementation does nothing.
void panDistanceBearingChanged(double distance, Qgis::DistanceUnit unit, double bearing)
Emitted whenever the distance or bearing of an in-progress panning operation is changed.
void canvasMoveEvent(QgsMapMouseEvent *e) override
Mouse move event for overriding. Default implementation does nothing.
void canvasReleaseEvent(QgsMapMouseEvent *e) override
Mouse release event for overriding. Default implementation does nothing.
bool gestureEvent(QGestureEvent *e) override
gesture event for overriding. Default implementation does nothing.
void activate() override
called when set as currently active map tool
Flags flags() const override
Returns the flags for the map tool.
Abstract base class for all map tools.
Definition: qgsmaptool.h:71
QPointer< QgsMapCanvas > mCanvas
The pointer to the map canvas.
Definition: qgsmaptool.h:341
QFlags< Flag > Flags
Definition: qgsmaptool.h:116
QString mToolName
The translated name of the map tool.
Definition: qgsmaptool.h:359
@ AllowZoomRect
Allow zooming by rectangle (by holding shift and dragging) while the tool is active.
Definition: qgsmaptool.h:113
@ ShowContextMenu
Show a context menu when right-clicking with the tool (since QGIS 3.14). See populateContextMenu().
Definition: qgsmaptool.h:114
virtual void activate()
called when set as currently active map tool
Definition: qgsmaptool.cpp:94
QCursor mCursor
The cursor used in the map tool.
Definition: qgsmaptool.h:344
virtual void deactivate()
called when map tool is being deactivated
Definition: qgsmaptool.cpp:110
A class to represent a 2D point.
Definition: qgspointxy.h:60
static QgsProject * instance()
Returns the QgsProject singleton instance.
Definition: qgsproject.cpp:481
QgsCoordinateTransformContext transformContext
Definition: qgsproject.h:113
A rectangle specified with double values.
Definition: qgsrectangle.h:42
void scale(double scaleFactor, const QgsPointXY *c=nullptr)
Scale the rectangle around its center point.
Definition: qgsrectangle.h:267