The Q3CanvasEllipse class provides an ellipse or ellipse segment on a Q3Canvas . 更多...
| 头： | #include <Q3CanvasEllipse> |
| 继承： | Q3CanvasPolygonalItem |
| Q3CanvasEllipse (Q3Canvas * canvas ) | |
| Q3CanvasEllipse (int width , int height , Q3Canvas * canvas ) | |
| Q3CanvasEllipse (int width , int height , int startangle , int angle , Q3Canvas * canvas ) | |
| ~Q3CanvasEllipse () | |
| int | angleLength () const |
| int | angleStart () const |
| int | height () const |
| void | setAngles (int start , int length ) |
| void | setSize (int width , int height ) |
| int | width () const |
| virtual Q3PointArray | areaPoints () const |
| virtual bool | collidesWith (const Q3CanvasItem * i ) const |
| virtual int | rtti () const |
| virtual void | drawShape (QPainter & p ) |
The Q3CanvasEllipse class provides an ellipse or ellipse segment on a Q3Canvas .
A canvas item that paints an ellipse or ellipse segment with a QBrush . The ellipse's height, width, start angle and angle length can be set at construction time. The size can be changed at runtime with setSize (), and the angles can be changed (if you're displaying an ellipse segment rather than a whole ellipse) with setAngles ().
Note that angles are specified in 16ths of a degree.
If a start angle and length angle are set then an ellipse segment will be drawn. The start angle is the angle that goes from zero in a counter-clockwise direction (shown in green in the diagram). The length angle is the angle from the start angle in a counter-clockwise direction (shown in blue in the diagram). The blue segment is the segment of the ellipse that would be drawn. If no start angle and length angle are specified the entire ellipse is drawn.
The ellipse can be drawn on a painter with drawShape ().
Like any other canvas item ellipses can be moved with move () 和 moveBy (), or by setting coordinates with setX (), setY () 和 setZ ().
注意： Q3CanvasEllipse does not use the pen.
另请参阅 QtCanvas and Porting to Graphics View .
Constructs a 32x32 ellipse, centered at (0, 0) on canvas .
构造 width by height pixel ellipse, centered at (0, 0) on canvas .
构造 width by height pixel ellipse, centered at (0, 0) on canvas . Only a segment of the ellipse is drawn, starting at angle startangle , and extending for angle angle (the angle length).
Note that angles are specified in sixteenths of a degree.
Destroys the ellipse.
Returns the length angle (the extent of the ellipse segment) in 16ths of a degree. Initially this will be 360 * 16 (a complete ellipse).
另请参阅 setAngles () 和 angleStart ().
Returns the start angle in 16ths of a degree. Initially this will be 0.
另请参阅 setAngles () 和 angleLength ().
[虚拟]
Q3PointArray
Q3CanvasEllipse::
areaPoints
() const
重实现自 Q3CanvasPolygonalItem::areaPoints ().
[虚拟]
bool
Q3CanvasEllipse::
collidesWith
(const
Q3CanvasItem
*
i
) const
重实现自 Q3CanvasItem::collidesWith ().
[virtual protected]
void
Q3CanvasEllipse::
drawShape
(
QPainter
&
p
)
重实现自 Q3CanvasPolygonalItem::drawShape ().
Draws the ellipse, centered at x (), y () using the painter p .
注意， Q3CanvasEllipse does not support an outline (the pen is always NoPen).
Returns the height of the ellipse.
[虚拟]
int
Q3CanvasEllipse::
rtti
() const
重实现自 Q3CanvasItem::rtti ().
Returns 6 ( Q3CanvasItem::Rtti_Ellipse ).
另请参阅 Q3CanvasItem::rtti ().
Sets the angles for the ellipse. The start angle is start and the extent of the segment is length (the angle length) from the start . The angles are specified in 16ths of a degree. By default the ellipse will start at 0 and have an angle length of 360 * 16 (a complete ellipse).
另请参阅 angleStart () 和 angleLength ().
设置 width and height of the ellipse.
Returns the width of the ellipse.