The QPolygonF class provides a vector of points using floating point precision. 更多...
| 头： | #include <QPolygonF> |
| qmake: | QT += gui |
| 继承： | QVector |
注意： 此类的所有函数 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 隐式共享 .
另请参阅 QVector , QPolygon ，和 QLineF .
构造副本为给定 polygon .
Constructs a float based polygon from the specified integer based polygon .
另请参阅 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.
另请参阅 isClosed ().
Constructs a polygon containing the specified points .
Constructs a polygon of the given size . Creates an empty polygon if size == 0.
另请参阅 QVector::isEmpty ().
Constructs a polygon with no points.
另请参阅 QVector::isEmpty ().
Destroys the polygon.
Returns the bounding rectangle of the polygon, or QRectF (0,0,0,0) if the polygon is empty.
另请参阅 QVector::isEmpty ().
返回
true
若给定
point
is inside the polygon according to the specified
fillRule
；否则返回
false
.
该函数在 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.
该函数在 Qt 4.3 引入。
另请参阅 intersects ().
返回
true
if the current polygon intersects at any point the given polygon
p
。也返回
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.
该函数在 Qt 5.10 引入。
另请参阅 intersected ().
返回
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.
另请参阅 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.
该函数在 Qt 4.3 引入。
Swaps polygon other with this polygon. This operation is very fast and never fails.
该函数在 Qt 4.8 引入。
创建并返回 QPolygon by converting each QPointF 到 QPoint .
另请参阅 QPointF::toPoint ().
Translate all points in the polygon by the given offset .
另请参阅 translated ().
这是重载函数。
Translates all points in the polygon by ( dx , dy ).
另请参阅 translated ().
Returns a copy of the polygon that is translated by the given offset .
该函数在 Qt 4.6 引入。
另请参阅 translate ().
这是重载函数。
Returns a copy of the polygon that is translated by ( dx , dy ).
该函数在 Qt 4.6 引入。
另请参阅 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.
该函数在 Qt 4.3 引入。
另请参阅 intersected () 和 subtracted ().
Returns the polygon as a QVariant .
写入给定 polygon 到给定 stream ，并返回流引用。
另请参阅 序列化 Qt 数据类型 .
Reads a polygon from the given stream 进给定 polygon ，并返回流引用。
另请参阅 序列化 Qt 数据类型 .