The QPolygonF class provides a vector of points using floating point precision. 更多...
| 頭： | #include <QPolygonF> |
| qmake: | QT += gui |
| 繼承： | QVector |
注意： 此類的所有函數 可重入 .
| QPolygonF (const QPolygonF & polygon ) | |
| QPolygonF (const QPolygon & polygon ) | |
| QPolygonF (const QRectF & rectangle ) | |
| QPolygonF (const QVector<QPointF> & points ) | |
| QPolygonF (int size ) | |
| QPolygonF () | |
| ~QPolygonF () | |
| QRectF | boundingRect () const |
| bool | containsPoint (const QPointF & point , Qt::FillRule fillRule ) const |
| QPolygonF | intersected (const QPolygonF & r ) const |
| bool | intersects (const QPolygonF & p ) const |
| bool | isClosed () const |
| QPolygonF | subtracted (const QPolygonF & r ) const |
| void | swap (QPolygonF & other ) |
| QPolygon | toPolygon () const |
| void | translate (const QPointF & offset ) |
| void | translate (qreal dx , qreal dy ) |
| QPolygonF | translated (const QPointF & offset ) const |
| QPolygonF | translated (qreal dx , qreal dy ) const |
| QPolygonF | united (const QPolygonF & r ) const |
| QVariant | operator QVariant () const |
| QDataStream & | operator<< (QDataStream & stream , const QPolygonF & polygon ) |
| QDataStream & | operator>> (QDataStream & stream , QPolygonF & polygon ) |
A QPolygonF is a QVector < QPointF >. The easiest way to add points to a QPolygonF is to use its streaming operator, as illustrated below:
QPolygonF polygon;
polygon << QPointF(10.4, 20.5) << QPointF(20.2, 30.2);
In addition to the functions provided by QVector , QPolygonF provides the boundingRect () 和 translate () functions for geometry operations. Use the QTransform::map () function for more general transformations of QPolygonFs.
QPolygonF also provides the isClosed () function to determine whether a polygon's start and end points are the same, and the toPolygon () function returning an integer precision copy of this polygon.
The QPolygonF class is 隱式共享 .
另請參閱 QVector , QPolygon ，和 QLineF .
構造副本為給定 polygon .
Constructs a float based polygon from the specified integer based polygon .
另請參閱 toPolygon ().
Constructs a closed polygon from the specified rectangle .
The polygon contains the four vertices of the rectangle in clockwise order starting and ending with the top-left vertex.
另請參閱 isClosed ().
Constructs a polygon containing the specified points .
Constructs a polygon of the given size . Creates an empty polygon if size == 0.
另請參閱 QVector::isEmpty ().
Constructs a polygon with no points.
另請參閱 QVector::isEmpty ().
Destroys the polygon.
Returns the bounding rectangle of the polygon, or QRectF (0,0,0,0) if the polygon is empty.
另請參閱 QVector::isEmpty ().
返迴
true
若給定
point
is inside the polygon according to the specified
fillRule
；否則返迴
false
.
該函數在 Qt 4.3 引入。
Returns a polygon which is the intersection of this polygon and r .
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
該函數在 Qt 4.3 引入。
另請參閱 intersects ().
返迴
true
if the current polygon intersects at any point the given polygon
p
。也返迴
true
if the current polygon contains or is contained by any part of
p
.
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
該函數在 Qt 5.10 引入。
另請參閱 intersected ().
返迴
true
if the polygon is closed; otherwise returns
false
.
A polygon is said to be closed if its start point and end point are equal.
另請參閱 QVector::first () 和 QVector::last ().
Returns a polygon which is r subtracted from this polygon.
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
該函數在 Qt 4.3 引入。
Swaps polygon other with this polygon. This operation is very fast and never fails.
該函數在 Qt 4.8 引入。
創建並返迴 QPolygon by converting each QPointF 到 QPoint .
另請參閱 QPointF::toPoint ().
Translate all points in the polygon by the given offset .
另請參閱 translated ().
這是重載函數。
Translates all points in the polygon by ( dx , dy ).
另請參閱 translated ().
Returns a copy of the polygon that is translated by the given offset .
該函數在 Qt 4.6 引入。
另請參閱 translate ().
這是重載函數。
Returns a copy of the polygon that is translated by ( dx , dy ).
該函數在 Qt 4.6 引入。
另請參閱 translate ().
Returns a polygon which is the union of this polygon and r .
Set operations on polygons will treat the polygons as areas. Non-closed polygons will be treated as implicitly closed.
該函數在 Qt 4.3 引入。
另請參閱 intersected () 和 subtracted ().
Returns the polygon as a QVariant .
寫入給定 polygon 到給定 stream ，並返迴流引用。
另請參閱 序列化 Qt 數據類型 .
Reads a polygon from the given stream 進給定 polygon ，並返迴流引用。
另請參閱 序列化 Qt 數據類型 .