1 /***************************************************************************
2 qgsmapmouseevent.cpp - mouse event in map coordinates and ability to snap
3 ----------------------
4 begin : October 2014
5 copyright : (C) Denis Rouzaud
6 email : denis.rouzaud@gmail.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
17 #include "qgsmapmouseevent.h"
18 #include "qgsmapcanvas.h"
19
20 #include "qgssnappingutils.h"
21 #include "qgssnappingconfig.h"
22
QgsMapMouseEvent(QgsMapCanvas * mapCanvas,QMouseEvent * event)23 QgsMapMouseEvent::QgsMapMouseEvent( QgsMapCanvas *mapCanvas, QMouseEvent *event )
24 : QMouseEvent( event->type(), event->pos(), event->button(), event->buttons(), event->modifiers() )
25 , mHasCachedSnapResult( false )
26 , mOriginalMapPoint( mapCanvas ? mapCanvas->mapSettings().mapToPixel().toMapCoordinates( event->pos() ) : QgsPointXY() )
27 , mMapPoint( mOriginalMapPoint )
28 , mPixelPoint( event->pos() )
29 , mMapCanvas( mapCanvas )
30 {
31 }
32
QgsMapMouseEvent(QgsMapCanvas * mapCanvas,QEvent::Type type,QPoint pos,Qt::MouseButton button,Qt::MouseButtons buttons,Qt::KeyboardModifiers modifiers)33 QgsMapMouseEvent::QgsMapMouseEvent( QgsMapCanvas *mapCanvas, QEvent::Type type, QPoint pos, Qt::MouseButton button, Qt::MouseButtons buttons, Qt::KeyboardModifiers modifiers )
34 : QMouseEvent( type, pos, button, buttons, modifiers )
35 , mHasCachedSnapResult( false )
36 , mOriginalMapPoint( mapCanvas ? mapCanvas->mapSettings().mapToPixel().toMapCoordinates( pos ) : QgsPointXY() )
37 , mMapPoint( mOriginalMapPoint )
38 , mPixelPoint( pos )
39 , mMapCanvas( mapCanvas )
40 {
41 }
42
snapPoint()43 QgsPointXY QgsMapMouseEvent::snapPoint()
44 {
45 // Use cached result
46 if ( mHasCachedSnapResult )
47 return mMapPoint;
48
49 mHasCachedSnapResult = true;
50
51 QgsSnappingUtils *snappingUtils = mMapCanvas->snappingUtils();
52 mSnapMatch = snappingUtils->snapToMap( mMapPoint, nullptr, true );
53
54 if ( mSnapMatch.isValid() )
55 {
56 mMapPoint = mSnapMatch.point();
57 mPixelPoint = mapToPixelCoordinates( mMapPoint );
58 }
59 else
60 {
61 mMapPoint = mOriginalMapPoint;
62 mPixelPoint = pos();
63 }
64
65 return mMapPoint;
66 }
67
setMapPoint(const QgsPointXY & point)68 void QgsMapMouseEvent::setMapPoint( const QgsPointXY &point )
69 {
70 mMapPoint = point;
71 mPixelPoint = mapToPixelCoordinates( point );
72 }
73
snapToGrid(double precision,const QgsCoordinateReferenceSystem & crs)74 void QgsMapMouseEvent::snapToGrid( double precision, const QgsCoordinateReferenceSystem &crs )
75 {
76 if ( precision <= 0 )
77 return;
78
79 try
80 {
81 QgsCoordinateTransform ct( mMapCanvas->mapSettings().destinationCrs(), crs, mMapCanvas->mapSettings().transformContext() );
82
83 QgsPointXY pt = ct.transform( mMapPoint );
84
85 pt.setX( std::round( pt.x() / precision ) * precision );
86 pt.setY( std::round( pt.y() / precision ) * precision );
87
88 pt = ct.transform( pt, QgsCoordinateTransform::ReverseTransform );
89
90 setMapPoint( pt );
91 }
92 catch ( QgsCsException &e )
93 {
94 Q_UNUSED( e )
95 }
96 }
97
mapToPixelCoordinates(const QgsPointXY & point)98 QPoint QgsMapMouseEvent::mapToPixelCoordinates( const QgsPointXY &point )
99 {
100 double x = point.x(), y = point.y();
101
102 mMapCanvas->mapSettings().mapToPixel().transformInPlace( x, y );
103
104 return QPoint( std::round( x ), std::round( y ) );
105 }
106