QGIS API Documentation 3.29.0-Master (8c80f25a4f)
qgsmaptoolzoom.cpp
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1/***************************************************************************
2 qgsmaptoolzoom.cpp - map tool for zooming
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
17#include <QRect>
18#include <QColor>
19#include <QCursor>
20#include <QPixmap>
21
22#include "qgsmaptoolzoom.h"
23#include "qgsmapcanvas.h"
24#include "qgsmaptopixel.h"
25#include "qgsrubberband.h"
26#include "qgslogger.h"
27#include "qgsmapmouseevent.h"
28#include "qgsapplication.h"
29
30
31
33 : QgsMapTool( canvas )
34 , mZoomOut( zoomOut )
35 , mNativeZoomOut( zoomOut )
36 , mDragging( false )
37 , mZoomOutCursor( QgsApplication::getThemeCursor( QgsApplication::Cursor::ZoomOut ) )
38 , mZoomInCursor( QgsApplication::getThemeCursor( QgsApplication::Cursor::ZoomIn ) )
39
40{
41 mToolName = tr( "Zoom" );
42 setZoomMode( mNativeZoomOut, true );
43}
44
46{
47 delete mRubberBand;
48}
49
50QgsMapTool::Flags QgsMapToolZoom::flags() const
51{
53}
54
56{
57 if ( !( e->buttons() & Qt::LeftButton ) )
58 return;
59
60 setZoomMode( e->modifiers().testFlag( Qt::AltModifier ) ^ mNativeZoomOut );
61
62 if ( !mDragging )
63 {
64 mDragging = true;
65 delete mRubberBand;
67 QColor color( Qt::blue );
68 color.setAlpha( 63 );
69 mRubberBand->setColor( color );
70 mZoomRect.setTopLeft( e->pos() );
71 }
72
73 mZoomRect.setBottomRight( e->pos() );
74 if ( mRubberBand )
75 {
77 mRubberBand->show();
78 }
79}
80
81
83{
84 if ( e->button() != Qt::LeftButton )
85 return;
86
87 mZoomRect.setTopLeft( e->pos() );
88 mZoomRect.setBottomRight( e->pos() );
89}
90
91
93{
94 if ( e->button() != Qt::LeftButton )
95 return;
96
97 if ( mCanceled )
98 {
99 mCanceled = false;
100 mDragging = false;
101 return;
102 }
103
104 setZoomMode( e->modifiers().testFlag( Qt::AltModifier ) ^ mNativeZoomOut );
105
106 // We are not really dragging in this case. This is sometimes caused by
107 // a pen based computer reporting a press, move, and release, all the
108 // one point.
109 const bool tooShort = ( mZoomRect.topLeft() - mZoomRect.bottomRight() ).manhattanLength() < mMinPixelZoom;
110 if ( !mDragging || tooShort )
111 {
112 mDragging = false;
113 delete mRubberBand;
114 mRubberBand = nullptr;
115
116 // change to zoom in/out by the default multiple
117 mCanvas->zoomWithCenter( e->x(), e->y(), !mZoomOut );
118 }
119 else
120 {
121 mDragging = false;
122 delete mRubberBand;
123 mRubberBand = nullptr;
124
125 // store the rectangle
126 mZoomRect.setRight( e->pos().x() );
127 mZoomRect.setBottom( e->pos().y() );
128
129 //account for bottom right -> top left dragging
130 mZoomRect = mZoomRect.normalized();
131
132 // set center and zoom
133 const QSize &zoomRectSize = mZoomRect.size();
134 const QgsMapSettings &mapSettings = mCanvas->mapSettings();
135 const QSize &canvasSize = mapSettings.outputSize();
136 const double sfx = static_cast<double>( zoomRectSize.width() ) / canvasSize.width();
137 const double sfy = static_cast<double>( zoomRectSize.height() ) / canvasSize.height();
138 const double sf = std::max( sfx, sfy );
139
140 const QgsMapToPixel *m2p = mCanvas->getCoordinateTransform();
141 const QgsPointXY c = m2p->toMapCoordinates( mZoomRect.center() );
142
143 mCanvas->zoomByFactor( mZoomOut ? 1.0 / sf : sf, &c );
144
145 mCanvas->refresh();
146 }
147}
148
150{
151 delete mRubberBand;
152 mRubberBand = nullptr;
153
155}
156
157void QgsMapToolZoom::setZoomMode( bool zoomOut, bool force )
158{
159 if ( !force && zoomOut == mZoomOut )
160 return;
161
162 mZoomOut = zoomOut;
164}
165
167{
168 if ( e->key() == Qt::Key_Alt )
169 {
170 setZoomMode( !mNativeZoomOut );
171 }
172}
173
175{
176 // key press events are not caught wile the mouse is pressed
177 // this is detected in map canvas move event
178
179 if ( e->key() == Qt::Key_Alt )
180 {
181 setZoomMode( mNativeZoomOut );
182 }
183
184 if ( e->key() == Qt::Key_Escape && mDragging )
185 {
186 mCanceled = true;
187 delete mRubberBand;
188 mRubberBand = nullptr;
189 }
190}
Extends QApplication to provide access to QGIS specific resources such as theme paths,...
Map canvas is a class for displaying all GIS data types on a canvas.
Definition: qgsmapcanvas.h:90
A QgsMapMouseEvent is the result of a user interaction with the mouse on a QgsMapCanvas.
The QgsMapSettings class contains configuration for rendering of the map.
QSize outputSize() const
Returns the size of the resulting map image, in pixels.
Perform transforms between map coordinates and device coordinates.
Definition: qgsmaptopixel.h:39
QgsPointXY toMapCoordinates(int x, int y) const
Transforms device coordinates to map (world) coordinates.
~QgsMapToolZoom() override
bool mDragging
Flag to indicate a map canvas drag operation is taking place.
void keyPressEvent(QKeyEvent *e) override
Key event for overriding. Default implementation does nothing.
bool mNativeZoomOut
native tool
QRect mZoomRect
stores actual zoom rect
void canvasPressEvent(QgsMapMouseEvent *e) override
Mouse press event for overriding. Default implementation does nothing.
bool mCanceled
Flag to indicate the user has canceled the current zoom operation.
QgsRubberBand * mRubberBand
Flags flags() const override
Returns the flags for the map tool.
QCursor mZoomOutCursor
void deactivate() override
called when map tool is being deactivated
QCursor mZoomInCursor
void canvasReleaseEvent(QgsMapMouseEvent *e) override
Mouse release event for overriding. Default implementation does nothing.
QgsMapToolZoom(QgsMapCanvas *canvas, bool zoomOut)
constructor
bool mZoomOut
indicates whether we're zooming in or out
void canvasMoveEvent(QgsMapMouseEvent *e) override
Mouse move event for overriding. Default implementation does nothing.
void keyReleaseEvent(QKeyEvent *e) override
Key event for overriding. Default implementation does nothing.
Abstract base class for all map tools.
Definition: qgsmaptool.h:71
QPointer< QgsMapCanvas > mCanvas
The pointer to the map canvas.
Definition: qgsmaptool.h:338
virtual void setCursor(const QCursor &cursor)
Sets a user defined cursor.
Definition: qgsmaptool.cpp:160
QString mToolName
The translated name of the map tool.
Definition: qgsmaptool.h:356
@ ShowContextMenu
Show a context menu when right-clicking with the tool (since QGIS 3.14). See populateContextMenu().
Definition: qgsmaptool.h:117
virtual void deactivate()
called when map tool is being deactivated
Definition: qgsmaptool.cpp:110
A class to represent a 2D point.
Definition: qgspointxy.h:59
A class for drawing transient features (e.g.
Definition: qgsrubberband.h:52
void setColor(const QColor &color)
Sets the color for the rubberband.
void setToCanvasRectangle(QRect rect)
Sets this rubber band to a map canvas rectangle.
As part of the API refactoring and improvements which landed in the Processing API was substantially reworked from the x version This was done in order to allow much of the underlying Processing framework to be ported into c