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QLineF Class Reference
[com.trolltech.qt.gui module]

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


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.

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. 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, and QRectF.


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Qt Jambi 4.3.2_01