- Qt 5.15
- Qt Positioning
- C++ Classes
- QGeoPolygon
- Qt 5.15.18 Reference Documentation

# QGeoPolygon Class

The QGeoPolygon class defines a geographic polygon. More...

Header: | #include <QGeoPolygon>
qmake: | QT += positioning
Since: | Qt 5.10
Inherits: | QGeoShape

This class was introduced in Qt 5.10.

- List of all members, including inherited members

## Public Functions

| QGeoPolygon(const QGeoShape &other)
| QGeoPolygon(const QGeoPolygon &other)
| QGeoPolygon(const QList<QGeoCoordinate> &path)
| QGeoPolygon()
QGeoPolygon & | operator=(const QGeoPolygon &other)
| ~QGeoPolygon()
void | addCoordinate(const QGeoCoordinate &coordinate)
void | addHole(const QVariant &holePath)
void | addHole(const QList<QGeoCoordinate> &holePath)
bool | containsCoordinate(const QGeoCoordinate &coordinate) const
QGeoCoordinate | coordinateAt(int index) const
const QVariantList | hole(int index) const
const QList<QGeoCoordinate> | holePath(int index) const
int | holesCount() const
void | insertCoordinate(int index, const QGeoCoordinate &coordinate)
double | length(int indexFrom = 0, int indexTo = -1) const
const QList<QGeoCoordinate> & | path() const
void | removeCoordinate(const QGeoCoordinate &coordinate)
void | removeCoordinate(int index)
void | removeHole(int index)
void | replaceCoordinate(int index, const QGeoCoordinate &coordinate)
void | setPath(const QList<QGeoCoordinate> &path)
int | size() const
QString | toString() const
void | translate(double degreesLatitude, double degreesLongitude)
QGeoPolygon | translated(double degreesLatitude, double degreesLongitude) const
bool | operator!=(const QGeoPolygon &other) const
bool | operator==(const QGeoPolygon &other) const

## Protected Functions

QVariantList | perimeter() const
void | setPerimeter(const QVariantList &path)

## Detailed Description

The polygon is defined by an ordered list of QGeoCoordinates representing its perimeter.

Each two adjacent elements in this list are intended to be connected together by the shortest line segment of constant bearing passing through both elements. This type of connection can cross the date line in the longitudinal direction, but never crosses the poles.

This is relevant for the calculation of the bounding box returned by QGeoShape::boundingGeoRectangle() for this shape, which will have the latitude of the top left corner set to the maximum latitude in the path point set. Similarly, the latitude of the bottom right corner will be the minimum latitude in the path point set.

This class is a Q_GADGET. It can be directly used from C++ and QML.

## Member Function Documentation

### QGeoPolygon::QGeoPolygon(const QGeoShape &other)

Constructs a new geo polygon from the contents of other.

### QGeoPolygon::QGeoPolygon(const QGeoPolygon &other)

Constructs a new geo polygon from the contents of other.

### QGeoPolygon::QGeoPolygon(const QList<QGeoCoordinate> &path)

Constructs a new geo polygon from the coordinates specified in path.

### QGeoPolygon::QGeoPolygon()

Constructs a new, empty geo polygon.

### QGeoPolygon &QGeoPolygon::operator=(const QGeoPolygon &other)

Assigns other to this geo polygon and returns a reference to this geo polygon.

### QGeoPolygon::~QGeoPolygon()

Destroys this polygon.

### void QGeoPolygon::addCoordinate(const QGeoCoordinate &coordinate)

Appends coordinate to the polygon.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### void QGeoPolygon::addHole(const QVariant &holePath)

Sets the holePath for a hole inside the polygon. The hole is a QVariant containing a QList<QGeoCoordinate>.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

This function was introduced in Qt 5.12.

### void QGeoPolygon::addHole(const QList<QGeoCoordinate> &holePath)

Overloaded method. Sets the holePath for a hole inside the polygon. The hole is a QList<QGeoCoordinate>.

This function was introduced in Qt 5.12.

### bool QGeoPolygon::containsCoordinate(const QGeoCoordinate &coordinate) const

Returns true if the polygon's perimeter contains coordinate as one of the elements.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### QGeoCoordinate QGeoPolygon::coordinateAt(int index) const

Returns the coordinate at index .

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### const QVariantList QGeoPolygon::hole(int index) const

Returns a QVariant containing a QVariant containing a QList<QGeoCoordinate> which represents the hole at index.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

This function was introduced in Qt 5.12.

### const QList<QGeoCoordinate> QGeoPolygon::holePath(int index) const

Returns a QList<QGeoCoordinate> which represents the hole at index.

This function was introduced in Qt 5.12.

### int QGeoPolygon::holesCount() const

Returns the number of holes.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

This function was introduced in Qt 5.12.

### void QGeoPolygon::insertCoordinate(int index, const QGeoCoordinate &coordinate)

Inserts coordinate at the specified index.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### double QGeoPolygon::length(int indexFrom = 0, int indexTo = -1) const

Returns the length of the polygon's perimeter, in meters, from the element indexFrom to the element indexTo. The length is intended to be the sum of the shortest distances for each pair of adjacent points.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### const QList<QGeoCoordinate> &QGeoPolygon::path() const

Returns all the elements of the polygon's boundary.

See also setPath().

### `[protected]` QVariantList QGeoPolygon::perimeter() const

Returns all the elements of the polygon's perimeter.

This function was introduced in QtPositioning 5.12.

See also setPerimeter().

### void QGeoPolygon::removeCoordinate(const QGeoCoordinate &coordinate)

Removes the last occurrence of coordinate from the polygon.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### void QGeoPolygon::removeCoordinate(int index)

Removes element at position index from the polygon.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### void QGeoPolygon::removeHole(int index)

Removes element at position index from the holes QList.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

This function was introduced in Qt 5.12.

### void QGeoPolygon::replaceCoordinate(int index, const QGeoCoordinate &coordinate)

Replaces the path element at the specified index with coordinate.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### void QGeoPolygon::setPath(const QList<QGeoCoordinate> &path)

Sets the path for the polygon.

See also path().

### `[protected]` void QGeoPolygon::setPerimeter(const QVariantList &path)

Sets all the elements of the polygon's perimeter based on a list of coordinates (path). .

This function was introduced in QtPositioning 5.12.

See also perimeter().

### int QGeoPolygon::size() const

Returns the number of elements in the polygon.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

This function was introduced in Qt 5.10.

### QString QGeoPolygon::toString() const

Returns the geo polygon properties as a string.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### void QGeoPolygon::translate(double degreesLatitude, double degreesLongitude)

Translates this geo polygon by degreesLatitude northwards and degreesLongitude eastwards.

Negative values of degreesLatitude and degreesLongitude correspond to southward and westward translation respectively.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

### QGeoPolygon QGeoPolygon::translated(double degreesLatitude, double degreesLongitude) const

Returns a copy of this geo polygon translated by degreesLatitude northwards and degreesLongitude eastwards.

Negative values of degreesLatitude and degreesLongitude correspond to southward and westward translation respectively.

Note: This function can be invoked via the meta-object system and from QML. See Q_INVOKABLE.

See also translate().

### bool QGeoPolygon::operator!=(const QGeoPolygon &other) const

Returns whether this geo polygon is not equal to other.

### bool QGeoPolygon::operator==(const QGeoPolygon &other) const

Returns whether this geo polygon is equal to other.