QGIS API Documentation 3.37.0-Master (fdefdf9c27f)
qgsrectangle.cpp
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1/***************************************************************************
2 qgsrectangle.cpp - description
3 -------------------
4 begin : Sat Jun 22 2002
5 copyright : (C) 2002 by Gary E.Sherman
6 email : sherman at mrcc.com
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
18#include "qgsgeometry.h"
19#include "qgspointxy.h"
20#include "qgsrectangle.h"
21#include "qgslogger.h"
22#include "qgsbox3d.h"
23#include "qgspolygon.h"
24#include "qgslinestring.h"
25
26#include <QString>
27#include <QTextStream>
28#include <QTransform>
29
30#include <algorithm>
31#include <cmath>
32#include <limits>
33
35{
36 const QgsGeometry geom = QgsGeometry::fromWkt( wkt );
37 if ( geom.isEmpty() )
38 return QgsRectangle();
39
40 if ( const QgsPolygon *polygon = qgsgeometry_cast< const QgsPolygon * >( geom.constGet()->simplifiedTypeRef() ) )
41 {
42 if ( polygon->numInteriorRings() > 0 )
43 return QgsRectangle();
44
45 if ( const QgsLineString *exterior = qgsgeometry_cast< QgsLineString * >( polygon->exteriorRing() ) )
46 {
47 if ( exterior->numPoints() == 5
48 && qgsDoubleNear( exterior->xAt( 0 ), exterior->xAt( 4 ) )
49 && qgsDoubleNear( exterior->yAt( 0 ), exterior->yAt( 4 ) )
50 && geom.isGeosValid() )
51 return QgsRectangle( exterior->xAt( 0 ), exterior->yAt( 0 ), exterior->xAt( 2 ), exterior->yAt( 2 ) );
52 }
53 }
54 return QgsRectangle();
55}
56
57QgsRectangle QgsRectangle::fromCenterAndSize( const QgsPointXY &center, double width, double height )
58{
59 const double xMin = center.x() - width / 2.0;
60 const double xMax = xMin + width;
61 const double yMin = center.y() - height / 2.0;
62 const double yMax = yMin + height;
63 return QgsRectangle( xMin, yMin, xMax, yMax );
64}
65
66QgsRectangle QgsRectangle::scaled( double scaleFactor, const QgsPointXY *center ) const
67{
68 QgsRectangle scaledRect = QgsRectangle( *this );
69 scaledRect.scale( scaleFactor, center );
70 return scaledRect;
71}
72
74{
75 const double xmin = mXmin - v.x();
76 const double xmax = mXmax - v.x();
77 const double ymin = mYmin - v.y();
78 const double ymax = mYmax - v.y();
79 return QgsRectangle( xmin, ymin, xmax, ymax );
80}
81
83{
84 const double xmin = mXmin + v.x();
85 const double xmax = mXmax + v.x();
86 const double ymin = mYmin + v.y();
87 const double ymax = mYmax + v.y();
88 return QgsRectangle( xmin, ymin, xmax, ymax );
89}
90
92{
93 mXmin -= v.x();
94 mXmax -= v.x();
95 mYmin -= v.y();
96 mYmax -= v.y();
97 return *this;
98}
99
101{
102 mXmin += v.x();
103 mXmax += v.x();
104 mYmin += v.y();
105 mYmax += v.y();
106 return *this;
107}
108
110{
111 QString rep =
112 qgsDoubleToString( mXmin ) + ' ' + qgsDoubleToString( mYmin ) + QLatin1String( ", " ) +
113 qgsDoubleToString( mXmax ) + ' ' + qgsDoubleToString( mYmax );
114
115 return rep;
116}
117
119{
120 if ( isNull() )
121 {
122 return QStringLiteral( "POLYGON EMPTY" );
123 }
124
125 return QStringLiteral( "POLYGON((%1 %2, %3 %2, %3 %4, %1 %4, %1 %2))" ).arg(
126 qgsDoubleToString( mXmin ),
127 qgsDoubleToString( mYmin ),
128 qgsDoubleToString( mXmax ),
129 qgsDoubleToString( mYmax )
130 );
131}
132
134{
135 QString rep;
136
137 if ( precision < 0 )
138 {
139 precision = 0;
140 if ( ( width() < 10 || height() < 10 ) && ( width() > 0 && height() > 0 ) )
141 {
142 precision = static_cast<int>( std::ceil( -1.0 * std::log10( std::min( width(), height() ) ) ) ) + 1;
143 // sanity check
144 if ( precision > 20 )
145 precision = 20;
146 }
147 }
148
149 if ( isNull() )
150 rep = QStringLiteral( "Null" );
151 else
152 rep = QStringLiteral( "%1,%2 : %3,%4" )
153 .arg( mXmin, 0, 'f', precision )
154 .arg( mYmin, 0, 'f', precision )
155 .arg( mXmax, 0, 'f', precision )
156 .arg( mYmax, 0, 'f', precision );
157
158 QgsDebugMsgLevel( QStringLiteral( "Extents : %1" ).arg( rep ), 4 );
159
160 return rep;
161}
162
164{
165 if ( isNull() )
166 {
167 return QStringLiteral( "EMPTY" );
168 }
169
170 QString rep;
171
172 QTextStream foo( &rep );
173
174 foo.setRealNumberPrecision( 8 );
175 foo.setRealNumberNotation( QTextStream::FixedNotation );
176 // NOTE: a polygon isn't a polygon unless its closed. In the case of
177 // a rectangle, that means 5 points (last == first)
178 foo
179 << mXmin << ' ' << mYmin << ", "
180 << mXmin << ' ' << mYmax << ", "
181 << mXmax << ' ' << mYmax << ", "
182 << mXmax << ' ' << mYmin << ", "
183 << mXmin << ' ' << mYmin;
184
185 return rep;
186
187}
188
189QgsBox3D QgsRectangle::toBox3d( double zMin, double zMax ) const
190{
191 return QgsBox3D( mXmin, mYmin, zMin, mXmax, mYmax, zMax );
192}
193
195{
196 if ( isNull() ) return *this;
197
198 // helper function
199 auto gridifyValue = []( double value, double spacing ) -> double
200 {
201 if ( spacing > 0 )
202 return std::round( value / spacing ) * spacing;
203 else
204 return value;
205 };
206
207 return QgsRectangle(
208 gridifyValue( mXmin, spacing ),
209 gridifyValue( mYmin, spacing ),
210 gridifyValue( mXmax, spacing ),
211 gridifyValue( mYmax, spacing )
212 );
213}
214
215QDataStream &operator<<( QDataStream &out, const QgsRectangle &rectangle )
216{
217 out << rectangle.xMinimum() << rectangle.yMinimum() << rectangle.xMaximum() << rectangle.yMaximum();
218 return out;
219}
220
221QDataStream &operator>>( QDataStream &in, QgsRectangle &rectangle )
222{
223 double xmin, ymin, xmax, ymax;
224 in >> xmin >> ymin >> xmax >> ymax;
225 rectangle.setXMinimum( xmin );
226 rectangle.setYMinimum( ymin );
227 rectangle.setXMaximum( xmax );
228 rectangle.setYMaximum( ymax );
229 return in;
230}
virtual const QgsAbstractGeometry * simplifiedTypeRef() const
Returns a reference to the simplest lossless representation of this geometry, e.g.
A 3-dimensional box composed of x, y, z coordinates.
Definition: qgsbox3d.h:43
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:162
const QgsAbstractGeometry * constGet() const
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
bool isGeosValid(Qgis::GeometryValidityFlags flags=Qgis::GeometryValidityFlags()) const
Checks validity of the geometry using GEOS.
static QgsGeometry fromWkt(const QString &wkt)
Creates a new geometry from a WKT string.
bool isEmpty() const
Returns true if the geometry is empty (eg a linestring with no vertices, or a collection with no geom...
Line string geometry type, with support for z-dimension and m-values.
Definition: qgslinestring.h:45
A class to represent a 2D point.
Definition: qgspointxy.h:60
double y
Definition: qgspointxy.h:64
Q_GADGET double x
Definition: qgspointxy.h:63
Polygon geometry type.
Definition: qgspolygon.h:33
A rectangle specified with double values.
Definition: qgsrectangle.h:42
QString toString(int precision=16) const
Returns a string representation of form xmin,ymin : xmax,ymax Coordinates will be truncated to the sp...
void scale(double scaleFactor, const QgsPointXY *c=nullptr)
Scale the rectangle around its center point.
Definition: qgsrectangle.h:267
QgsRectangle & operator+=(QgsVector v)
Moves this rectangle in the direction of the vector.
QgsRectangle()=default
Constructor for a null rectangle.
double xMinimum() const
Returns the x minimum value (left side of rectangle).
Definition: qgsrectangle.h:201
static QgsRectangle fromWkt(const QString &wkt)
Creates a new rectangle from a wkt string.
void setYMinimum(double y)
Set the minimum y value.
Definition: qgsrectangle.h:159
QgsRectangle & operator-=(QgsVector v)
Moves this rectangle in the direction of the reversed vector.
double yMinimum() const
Returns the y minimum value (bottom side of rectangle).
Definition: qgsrectangle.h:211
void setXMinimum(double x)
Set the minimum x value.
Definition: qgsrectangle.h:149
QString asWktPolygon() const
Returns a string representation of the rectangle as a WKT Polygon.
double width() const
Returns the width of the rectangle.
Definition: qgsrectangle.h:236
double xMaximum() const
Returns the x maximum value (right side of rectangle).
Definition: qgsrectangle.h:196
bool isNull() const
Test if the rectangle is null (holding no spatial information).
Definition: qgsrectangle.h:505
QString asWktCoordinates() const
Returns a string representation of the rectangle in WKT format.
QgsRectangle operator-(QgsVector v) const
Returns a rectangle offset from this one in the direction of the reversed vector.
double yMaximum() const
Returns the y maximum value (top side of rectangle).
Definition: qgsrectangle.h:206
QgsRectangle scaled(double scaleFactor, const QgsPointXY *center=nullptr) const
Scale the rectangle around its center point.
void setYMaximum(double y)
Set the maximum y value.
Definition: qgsrectangle.h:164
QgsPointXY center() const
Returns the center point of the rectangle.
Definition: qgsrectangle.h:262
void setXMaximum(double x)
Set the maximum x value.
Definition: qgsrectangle.h:154
static QgsRectangle fromCenterAndSize(const QgsPointXY &center, double width, double height)
Creates a new rectangle, given the specified center point and width and height.
QString asPolygon() const
Returns the rectangle as a polygon.
double height() const
Returns the height of the rectangle.
Definition: qgsrectangle.h:243
QgsRectangle snappedToGrid(double spacing) const
Returns a copy of this rectangle that is snapped to a grid with the specified spacing between the gri...
QgsRectangle operator+(QgsVector v) const
Returns a rectangle offset from this one in the direction of the vector.
QgsBox3D toBox3d(double zMin, double zMax) const
Converts the rectangle to a 3D box, with the specified zMin and zMax z values.
A class to represent a vector.
Definition: qgsvector.h:30
double y() const
Returns the vector's y-component.
Definition: qgsvector.h:152
double x() const
Returns the vector's x-component.
Definition: qgsvector.h:143
QString qgsDoubleToString(double a, int precision=17)
Returns a string representation of a double.
Definition: qgis.h:5124
bool qgsDoubleNear(double a, double b, double epsilon=4 *std::numeric_limits< double >::epsilon())
Compare two doubles (but allow some difference)
Definition: qgis.h:5207
#define QgsDebugMsgLevel(str, level)
Definition: qgslogger.h:39
QDataStream & operator>>(QDataStream &in, QgsRectangle &rectangle)
Reads a rectangle from stream in into rectangle.
QDataStream & operator<<(QDataStream &out, const QgsRectangle &rectangle)
Writes the list rectangle to stream out.
int precision