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QLineF Class Reference

List of all members.


Detailed Description

The QLineF class provides a two-dimensional vector using floating point precision.

A QLineF describes a finite length line (or line segment) on a two-dimensional surface. QLineF defines the start and end points of the line using floating point accuracy for coordinates. Use the toLine() function to retrieve an integer based copy of this line.

qline-point.png qline-coordinates.png

The positions of the line's start and end points can be retrieved using the p1(), x1(), y1(), p2(), x2(), and y2() functions. The dx() and dy() functions return the horizontal and vertical components of the line, respectively.

The line's length can be retrieved using the length() function, and altered using the setLength() function. Similarly, angle() and setAngle() are respectively used for retrieving and altering the angle of the line. Use the isNull() function to determine whether the QLineF represents a valid line or a null line.

The intersect() function determines the IntersectType for this line and a given line, while the angle() function returns the angle between the lines. In addition, the unitVector() function returns a line that has the same starting point as this line, but with a length of only 1, while the normalVector() function returns a line that is perpendicular to this line with the same starting point and length.

Finally, the line can be translated a given offset using the translate() function, and can be traversed using the pointAt() function.

See also:
QLine, QPolygonF, QRectF

Definition at line 207 of file qline.h.


Public Types

enum  IntersectType { NoIntersection, BoundedIntersection, UnboundedIntersection }

Public Member Functions

qreal angle (const QLineF &l) const
qreal angle () const
qreal angleTo (const QLineF &l) const
qreal dx () const
qreal dy () const
IntersectType intersect (const QLineF &l, QPointF *intersectionPoint) const
bool isNull () const
qreal length () const
QLineF normalVector () const
bool operator!= (const QLineF &d) const
bool operator== (const QLineF &d) const
QPointF p1 () const
QPointF p2 () const
QPointF pointAt (qreal t) const
 QLineF (const QLine &line)
 QLineF (qreal x1, qreal y1, qreal x2, qreal y2)
 QLineF (const QPointF &pt1, const QPointF &pt2)
 QLineF ()
void setAngle (qreal angle)
void setLength (qreal len)
void setLine (qreal x1, qreal y1, qreal x2, qreal y2)
void setP1 (const QPointF &p1)
void setP2 (const QPointF &p2)
void setPoints (const QPointF &p1, const QPointF &p2)
QLine toLine () const
void translate (qreal dx, qreal dy)
void translate (const QPointF &p)
QLineF translated (qreal dx, qreal dy) const
QLineF translated (const QPointF &p) const
QLineF unitVector () const
qreal x1 () const
qreal x2 () const
qreal y1 () const
qreal y2 () const

Static Public Member Functions

static QLineF fromPolar (qreal length, qreal angle)

Private Attributes

QPointF pt1
QPointF pt2

Related Functions

(Note that these are not member functions.)

QDataStreamoperator<< (QDataStream &stream, const QLineF &line)
QDataStreamoperator>> (QDataStream &stream, QLineF &line)

The documentation for this class was generated from the following files:

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